Greater North Sea

Information on the distribution, intensity, impact and economic value of mobile bottom contacting gear (MBCG) fisheries within the Greater North Sea area and associated subdivisions, and estimated consequences and costs (landings weight, landings value) of reducing their relative extent.

Greater North Sea

Summary

Geographic scope: The assessment in this interactive document covers EU waters of depths shallower than 800 m in the MSFD subdivisions associated with the Greater North Sea area. EU waters are the waters defined by EU Member States, in this area, for MSFD implementation purposes (Figure E1).

Spatial scales of analyses: Analyses are presented by MSFD subdivision, MSFD broad habitat type (BHT) and for depth strata 0‒200 m, 200‒400 m, and 400‒800 m. The 0.05° × 0.05° c-squares (hereafter c-squares) were allocated to subdivisions based on centroid positions. Mean depths in c-squares were used to allocate c-squares to depth strata. For the Baltic Sea area, the subdivisions are as used in the ICES 2021 advice (ICES, 2021) and based on the HELCOM sub-basins (HELCOM, 2013). For the Greater North Sea, Celtic Seas and Bay of Biscay and the Iberian Coast areas, the subdivisions used are the OSPAR benthic habitat assessment area units (OSPAR, 2022), as used in the OSPAR 2023 Quality Status Report (OSPAR, 2023). The extent of BHTs, as defined under the MSFD, is determined per c-square.

Values of pressure indicators (I‒1 to I‒5) and impact indicators (I‒6a, I‒6b, I‒7a, and I‒7b) by depth strata (Table 1) provide information on the distribution, intensity, and impact of MBCG fisheries. The indicators are described in the “Essential information” tab in this document.

For depths of 0‒200 m, 71.5% of the area is fished with MBCG per year (I‒3). However, 90% of the total MBCG swept area is concentrated in an annual average of 46.1% of the Greater North Sea area. Five point five per cent of the area at these depths was not fished with MBCG at all from 2017‒2022, based on the data submissions received. For depths of 0‒200m, MBCG fishing was estimated to reduce the total biomass of benthic fauna by 19% (I‒6a) and reduce the total biomass of sensitive fauna by 28.4% (I‒6b). Within this depth strata, the depletion of benthic fauna was less than 20% in 68.1% (I‒7a) of the area. For sensitive fauna the corresponding area was 55.7% (I‒7b). The heterogeneous distributions of annual mean fishing intensity (swept area ratio [SAR]), annual mean total landings values (euros) and weight (kg), and seabed sensitivity (as estimated median longevity of the benthic fauna), are illustrated in Figure 1. The distributions of the fishing intensity and the seabed sensitivity account for the values of pressure and impact indicators reported in Table 1.

Small-scale fisheries, defined as vessels < 12 m in overall length deploying MBCG, operate in the Greater North Sea area as well. As these are not required to carry VMS by the EU Control Regulation (EU, 2009), their coverage in the VMS data submissions is unknown. The EU Fisheries Dependent Information (FDI) data does report on small-scale fisheries effort in kW × fishing days. However, the FDI reporting units differ from the subdivisions, BHTs, and depth strata used in these analyses. The correspondence between subdivisions and FDI reporting regions is illustrated in Figure E1. The incomplete data for small-scale fisheries results in underestimates of fishing intensity and impact, especially in inshore areas. In the Greater North Sea area the proportion of the total kW × fishing days of MBCG fishing attributed to small-scale fisheries (Table 2) varies from 0 - 42% between FAO regions.

References:

EU Council. 2009. Council Regulation (EC) No 1224/2009 of 20 November 2009 establishing a Community control system for ensuring compliance with the rules of the Common Fisheries Policy amending Regulations (EC) No 847/96, (EC) No 2371/2002, (EC) No 811/2004, (EC) No 768/2005, (EC) No 2115/2005, (EC) No 2166/2005, (EC) No 388/2006, (EC) No 509/2007, (EC) No 676/2007, (EC) No 1098/2007, (EC) No 1300/2008, (EC) No 1342/2008 and repealing Regulations (EEC) No 2847/93, (EC) No 1627/94 and (EC) No 1966/2006. Official Journal of the European Union L343, 1−50. http://data.europa.eu/eli/reg/2009/1224/oj

HELCOM. 2013. HELCOM Monitoring and Assessment Strategy. https://helcom.fi/wp-content/uploads/2020/02/Monitoring-and-assessment-strategy.pdf

ICES. 2021. ICES advice to the EU on how management scenarios to reduce mobile bottom fishing disturbance on seafloor habitats affect fisheries landing and value. In Report of the ICES Advisory Committee, 2021. ICES Advice 2021. sr.2021.08. https://doi.org/10.17895/ices.advice.8191

OSPAR. 2022. OSPAR Extent of Physical Disturbance to Benthic Habitats Assessment Units. https://odims.ospar.org/en/submissions/ospar_phys_dist_habs_au_2022_06/

OSPAR. 2023. OSPAR Quality Status Report. https://oap.ospar.org/en/ospar-assessments/quality-status-reports/qsr-2023/

Table 1

Table 1. Values of pressure and impact indicators for 2017‒2022 for three depth strata in the Greater North Sea area. Values of I‒1, I‒2, I‒3, I‒4, I‒6a, I‒6b, I‒7a and I‒7b are annual means and I‒5 is evaluated over the six years. Descriptions of the pressure and impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Indicators	0 to 200 m	200 to 400 m	400 to 800 m
I‒1: Average fishing intensity	2.65	7.98	1.05
I‒2: Proportion of area fished, evaluated at c-square scale (%)	94.50	100.00	67.70
I‒3: Proportion of area fished (%)	71.50	97.30	40.30
I‒4: Smallest proportion of area with 90% of fishing intensity, evaluated at c-square scale (%)	46.10	72.60	27.10
I‒5: Proportion of area persistently unfished, evaluated at c-square scale (%)	5.50	0.00	32.30
I‒6a: Average PD impact	19.00	NA	NA
I‒6b: Average PD-sens impact	28.40	NA	NA
I‒7a: Proportion of area with PD impact < 0.2, evaluated at c-square scale (%)	68.10	NA	NA
I‒7b: Proportion of area with PD-sens impact < 0.2, evaluated at c-square scale (%)	55.70	NA	NA

Figure 1

Figure 1. Geographic distribution of fishing intensity (swept area ratio), seabed sensitivity (community longevity), total landings value, and total landings weight from mobile bottom-contacting gear (MBCG) in the Greater North Sea area. The maps of swept area ratio, landings value, and landings weight show annual means evaluated at the c-square scale.

Table 2

Table 2. Contribution of small-scale fisheries (vessels < 12 m overall length) to total fishing effort (kW × fishing days) in the Greater North Sea area. The table shows the total fishing effort (kW × fishing days) by FAO region over the assessment period, and the mean contribution (%) and observed range in contribution (%) of small-scale MBCG fisheries.

FAO region code	FAO region name	Total fishing effort (kW × Fishing days)	Mean contribution SSF (%)	Observed range SSF contribution (%) [min - max]
27.3.a.20	Skagerrak	8589114	8.2	[6 - 11]
27.3.a.21	Kattegat	2933089	12.3	[11 - 13]
27.3.b.23	The Sound	11237	41.8	[7 - 75]
27.4.a	Northern North Sea	6518051	0.0	[0 - 0]
27.4.b	Central North Sea	24194203	1.0	[1 - 1]
27.4.c	Southern North Sea	19239402	0.0	[0 - 0]
27.7.d	Western English Channel	12365350	17.3	[16 - 18]
27.7.e	Eastern English Channel	8267271	32.8	[31 - 35]

Fishing intensity

The extent and relative abundance of BHTs in the Greater North Sea area are presented in Table 3. This table also presents landings weight and landings value and the intensity of MBCG fisheries operating in these habitats. Note that fishing data is only available at the c-square scale and is assumed to be uniformly distributed over all habitat types present in a c-square. Each habitat type present is proportionally assigned the fishing data registered in a c-square.

The most extensive habitat type is Circalittoral sand occupying 58.13 ×1000 km² (27.2%). The average fishing intensity (swept area ratio) on this habitat is 1.94, covering annually on average 69.1% of the habitat extent. Ninety per cent of the fishing effort in this BHT however, is concentrated to 53.7% of the habitat extent. Three point one per cent of this habitat is located in c squares that are persistently not fished. The largest landing (in tonnes) is derived from fishing on Circalittoral sand, and the greatest landings values come from fishing on Circalittoral sand.

Temporal variation of the pressure indicators I−1, I−3, and I−4 are shown in Figure 2 for the Greater North Sea area.

Table 3

Table 3. Extent (in km² and %) of broad habitat types in the Greater North Sea area, and mean annual estimates of MBCG fishing intensity, landings weight, and landings value. In addition, estimates of the average annual proportion of the fished extent, the smallest proportion of the habitat extent affected by 90% of the fishing effort, and the proportion of extent persistently unfished are provided.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Relative habitat extent (%)	Landings (×1000 tonnes)	Value (×106 euro)	Swept area (×1000 km2)	Average fishing intensity (I‒1)	Average annual extent fished (%)	Smallest proportion of extent with 90% of fishing effort (%)	Percentage extent persistently unfished (%)
Circalittoral sand	58.13	27.2	82.75	135.58	112.62	1.94	69.1	53.7	3.1
Offshore circalittoral sand	50.93	23.8	56.24	101.20	118.31	2.32	78.7	61.4	0.2
Offshore circalittoral mud	42.52	19.9	36.13	92.57	151.06	3.55	88.6	58.8	0.2
Offshore circalittoral coarse sediment	19.70	9.2	38.13	99.57	104.73	5.32	78.7	51.3	0.1
Circalittoral coarse sediment	11.56	5.4	19.63	35.20	40.76	3.53	62.3	38.5	3.0
Infralittoral sand	8.96	4.2	15.05	29.10	11.90	1.33	36.5	28.9	42.9
Circalittoral mud	6.41	3.0	11.85	16.39	14.02	2.19	60.5	48.1	12.0
Circalittoral mixed sediment	4.50	2.1	4.14	4.47	4.22	0.94	38.8	39.8	17.9
Offshore circalittoral mixed sediment	2.95	1.4	2.05	5.95	7.52	2.54	71.9	60.9	1.0
Upper bathyal sediment	2.48	1.2	2.48	12.60	15.51	6.27	83.4	62.5	7.9
Infralittoral mud	1.37	0.6	7.60	4.52	0.92	0.67	22.2	23.9	44.5
Infralittoral coarse sediment	1.23	0.6	3.88	7.71	2.15	1.75	55.3	50.2	23.9
Infralittoral mixed sediment	1.11	0.5	0.65	0.38	0.08	0.07	4.4	14.9	60.8
Unknown	0.85	0.4	1.45	3.63	3.28	3.84	90.4	65.8	0.5
Offshore circalittoral rock and biogenic reef	0.56	0.3	0.38	1.53	1.32	2.34	51.9	40.0	4.1
Circalittoral rock and biogenic reef	0.42	0.2	0.18	0.60	0.33	0.79	30.1	30.3	19.0
Infralittoral rock and biogenic reef	0.30	0.1	0.27	0.79	0.32	1.06	32.4	27.7	17.4
Upper bathyal rock and biogenic reef	0.00	0.0	0.00	0.00	0.00	4.04	98.2	NA	0.0

Figure 2

Figure 2. Temporal variation of the pressure indicators I‒1, I‒3 and I‒4 in the Greater North Sea area. Descriptions of the pressure indicators are provided in the ‘Essential Information’ Table E1 in this document.

Fishing by métier

Relationships between swept area and the landings weight and landings value of the métiers show the landings and economic returns as a function of swept area (Table 4). The most active métier within the Greater North Sea area is OT_CRU. This métier lands 114.57 kg of fish with a value of 578.23 euro per km² swept area.

The métier with the highest landing per swept area is TBB_MOL, and the métier with the highest economic return per swept area is TBB_MOL.

Table 4

Table 4. Landings weight and value by métier and their relationship with swept area in the Greater North Sea area.

	OT_CRU	OT_DMF	SSC_DMF	TBB_DMF	SDN_DMF	TBB_CRU	OT_MI	DRB_MOL	OT_SPF	TBB_MOL
Area swept (×1000 km2)	158.83	138.94	83.85	67.29	58.46	48.16	23.20	9.67	5.43	0.03
Landings (×1000 tonnes)	18.20	98.24	6.18	32.24	5.13	22.26	9.09	62.37	28.58	0.59
Value (×106 euro)	91.84	68.70	14.52	125.32	13.96	91.15	24.72	111.67	9.20	0.74
Landings / Area swept (kg/km2)	114.57	707.06	73.66	479.09	87.77	462.20	392.03	6451.50	5267.18	20525.84
Value / Area swept (euro/km2)	578.23	494.42	173.17	1862.40	238.86	1892.74	1065.72	11550.37	1695.01	25674.36

Core fishing grounds

Core fishing grounds are defined as the smallest area yielding 90% of the landings value, evaluated annually at the c-square scale. The spatial stability of core fishing grounds over the assessment period 2017−2022 is described as the number of years a c-square is identified as a core fishing ground. This spatial extent and stability of the core fishing grounds varies among métiers (Figures 3 and 4).

Métier OT_SPF has 61.9% of the Greater North Sea area identified at least once as a core fishing ground. For métier OT_CRU, this extent is much smaller (25.9%). The most stable core fishing grounds (highest fraction of core fishing ground c-squares identified as core fishing ground in all six years) are observed for OT_CRU, whereas the métier OT_SPF shows the least stable core fishing grounds in the Greater North Sea area.

Overall, there is considerable variation in the stability of core fishing grounds among métiers. This is expected to be a consequence of interannual movements of fishing locations because of the habitat affinity of the variety of fish and shellfish targeted by different métiers (Table 5 in the main advice document) and the effects of economic and regulatory factors.

Figure 3

Figure 3. Spatial stability of core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Greater North Sea area. Only métiers that were active within > 50 unique c-squares during the assessment period are included. The numbers between brackets show the proportion of fished extent compared to the overall assessed area extent.

Figure 4

Figure 4. Spatial distribution of the stability of the core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Greater North Sea area. Only métiers that were active within > 50 unique c-squares during the assessment period are included.

Impact

Fishing impact, as assessed with the PD indicator (I−6a) and the PD-sens indicator (I−6b), results from the fishing intensity for MBCG métiers and the median longevity of the benthic fauna (Figure 1) as well as métier-specific depletion rates per trawl pass (Table 5 in the main advice document). The PD-sens indicator only considers sensitive fauna and shows greater impacts than the PD indicator (Figures 5 and 6).

The spatial distribution of the fishing impact in the Greater North Sea area is shown in Figure 5. When based on the PD indicator, fishing impact is 0.19 on average (I−6a), with 67% of the area having a fishing impact below 0.2 (I−7a; Figure 6). For the PD-sens indicator, the average impact is 0.29 (I−6b), with 54% of the area having less impact than 0.2 (I−7b; Figure 6).

For the OT_CRU métier, which accounts for the largest proportion of swept area (Table 4), landing weight is 15.4 tonnes and landings value 77300 euro per unit of PD impact. Similarly, landing weight is 11.4 tonnes and landings value 57400 per unit of PD-sens impact (Table 5). The métier with the highest landings weight per unit impact is OT_SPF (1405 tonnes), and the métier with the highest landings value per unit impact is the TBB_MOL (926200 euros).

Métier-related impacts, as measured with the PD and PD-sens indicators, vary among BHTs because of variations in fishing intensity, seabed sensitivity (Figure 1), and the depletion rate of the specific métier (Table 5 in the main advice document; Figure 7). The largest PD and PD sens impacts in the Greater North Sea area are attributed to the OT_CRU métier fishing on Offshore circalittoral mud.

Figure 5

Figure 5. The spatial distribution of MBCG fisheries impact in the Greater North Sea area, as assessed with the PD indicator (I‒6a) and PD-sens indicator (I‒6b), shown as annual means for the assessment period, evaluated at the c-square scale. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Figure 6

Figure 6. Temporal variation in values of the PD indicator (I‒6a), PD-sens indicator (I‒6b), proportion of the extent with PD impact < 0.2 (I‒7a) and proportion of extent with PD-sens impact < 0.2 (I‒7b), shown for the overall area and for the four most extensive broad habitat types separately in the Greater North Sea area. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Table 5

Table 5. Métier-specific landings weight and value per unit PD or PD-sens impact in the Greater North Sea area.

	OT_CRU	OT_DMF	SSC_DMF	TBB_DMF	SDN_DMF	TBB_CRU	OT_MI	DRB_MOL	OT_SPF	TBB_MOL
Landings (tonnes)/PD impact	15.4	295.7	64.3	47.6	71.2	106.8	74.4	355.1	1405.0	740.4
Value (×1000 euro)/PD impact	77.3	203.3	151.2	184.9	193.8	437.3	202.1	635.7	451.7	926.2
Landings (tonnes)/PD-sens impact	11.4	186.1	37.7	29.9	45.2	73.0	46.4	239.0	1295.5	701.6
Value (×1000 euro)/PD-sens impact	57.4	128.0	88.7	116.3	123.0	298.8	126.0	427.9	416.5	877.6

Figure 7

Figure 7. Métier-related impacts, reported as annual means of the PD indicator (I‒6a, top) and PD-sens indicator (I‒6b, bottom), on the four most extensive broad habitat types in the Greater North Sea area.

Scenarios

Footprint reduction

The fishing footprint reduction scenarios illustrate the effects of stepwise MBCG fisheries exclusion from specified proportions of each BHT within the Greater North Sea area. The stepwise exclusion is conducted in 10% increments, ranging from 10% to 90%. In each successive increment, the c-squares containing the least MBCG swept area are excluded. The resulting reduction in swept area (Table 6), landings weight (Table 7), and landings value (Table 8) is presented for the prevailing BHTs combined and for each type separately.

For example, the analysis shows that the exclusion of MBCG from 30% of all prevailing BHTs types is affecting 4.5% of the footprint (Table 6), 8.4% of the landings weight (Table 7), and 5.9% of the landings value (Table 8). In this example, the pattern reflects the extent to which MBCG fishing activity is concentrated in core areas, with relatively low effort and landings in peripheral areas.

Table 6: Effort

Table 6. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Greater North Sea area, on swept area (presented as % of total swept area within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total area swept (×1000 km2	10%	20%	30%	40%	50%	60%	70%	80%	90%
total	213.98	100	0.8	2.3	4.5	7.8	12.3	18.4	26.8	38.5	56.6
Circalittoral sand	58.13	112.62	0.1	1.1	3.3	7.0	12.1	18.8	27.5	38.4	56.0
Offshore circalittoral sand	50.93	118.31	1.4	4.1	7.1	10.5	14.8	20.5	27.4	36.2	50.1
Offshore circalittoral mud	42.52	151.06	1.5	3.5	6.1	9.6	14.1	20.6	30.0	44.0	63.5
Offshore circalittoral coarse sediment	19.7	104.73	0.3	1.0	2.6	5.7	10.8	17.6	26.8	39.8	60.0
Circalittoral coarse sediment	11.56	40.76	<0.1	0.5	1.5	3.2	5.6	9.3	14.2	20.8	36.5
Infralittoral sand	8.96	11.9	0.0	0.0	0.0	0.0	0.1	1.6	9.8	28.0	54.8
Circalittoral mud	6.41	14.02	0.0	0.3	2.1	5.7	10.4	17.7	27.3	42.2	63.5
Circalittoral mixed sediment	4.5	4.22	0.0	<0.1	0.4	1.8	5.0	10.2	18.7	27.2	50.3
Offshore circalittoral mixed sediment	2.95	7.52	0.6	3.1	6.1	10.5	15.8	23.2	31.9	45.3	66.5
Upper bathyal sediment	2.48	15.51	6.4	13.7	19.9	27.8	33.8	44.3	52.8	68.9	82.9
Infralittoral mud	1.37	0.92	0.0	0.0	0.0	0.0	<0.1	2.5	8.5	19.9	39.5
Infralittoral coarse sediment	1.23	2.15	0.0	0.0	<0.1	1.6	11.5	22.0	30.7	46.3	71.0
Infralittoral mixed sediment	1.11	0.08	0.0	0.0	0.0	0.0	0.0	0.0	1.2	5.2	19.5
Unknown	0.85	3.28	2.6	5.2	9.2	12.0	16.7	28.2	44.6	63.8	83.5
Offshore circalittoral rock and biogenic reef	0.56	1.32	<0.1	0.5	1.0	2.3	5.2	10.1	16.5	35.3	57.0
Circalittoral rock and biogenic reef	0.42	0.33	0.0	<0.1	0.1	0.7	2.6	5.4	10.1	22.0	48.9
Infralittoral rock and biogenic reef	0.3	0.32	0.0	<0.1	0.1	0.3	0.8	2.2	5.3	21.4	40.1
Upper bathyal rock and biogenic reef	0	0	9.2	29.9	29.9	29.9	29.9	100.0	100.0	100.0	100.0

Table 7: Landings weight

Table 7. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Greater North Sea area, on landings weight (presented as % of total landings weight within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings weight (×1000 kg)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	213.98	262158.7	2.0	4.8	8.4	12.8	18.5	25.6	34.8	46.8	65.9
Circalittoral sand	58.13	81560.1	0.3	1.9	5.1	7.7	11.4	17.4	24.4	35.1	54.5
Offshore circalittoral sand	50.93	56068.4	3.4	8.3	12.8	17.2	23.3	30.3	37.6	45.7	66.2
Offshore circalittoral mud	42.52	35900.3	7.5	14.6	20.9	29.6	39.5	48.6	58.1	68.6	80.3
Offshore circalittoral coarse sediment	19.7	38120.7	0.5	1.4	3.5	7.7	14.6	22.6	33.8	53.0	69.5
Circalittoral coarse sediment	11.56	19284.8	0.1	1.2	2.9	7.2	10.6	17.2	25.2	37.9	71.3
Infralittoral sand	8.96	11839.5	0.0	0.0	0.0	0.0	0.7	5.9	30.5	45.4	66.0
Circalittoral mud	6.41	5387.2	0.0	1.6	9.1	23.5	38.4	46.6	55.7	72.4	83.4
Circalittoral mixed sediment	4.5	3902.7	0.0	<0.1	0.6	1.9	4.5	8.5	16.8	24.9	40.7
Offshore circalittoral mixed sediment	2.95	2053.1	1.4	8.3	12.3	20.4	30.7	40.2	54.6	70.1	82.5
Upper bathyal sediment	2.48	258.3	6.7	14.0	21.1	30.9	36.4	48.1	56.7	70.7	83.0
Infralittoral mud	1.37	1639.4	0.0	0.0	0.0	0.0	0.7	10.8	23.3	45.4	88.4
Infralittoral coarse sediment	1.23	3815.4	0.0	0.0	<0.1	3.0	12.6	23.9	38.0	59.2	82.8
Infralittoral mixed sediment	1.11	112.5	0.0	0.0	0.0	0.0	0.0	0.0	0.7	2.9	38.2
Unknown	0.85	1424.9	4.3	8.3	37.5	42.6	46.5	61.4	75.1	81.9	93.0
Offshore circalittoral rock and biogenic reef	0.56	371.2	0.4	0.8	1.3	2.4	5.1	11.0	17.0	45.2	62.6
Circalittoral rock and biogenic reef	0.42	172.4	0.0	<0.1	0.1	0.7	2.8	4.2	9.0	27.4	36.5
Infralittoral rock and biogenic reef	0.3	247.7	0.0	<0.1	0.1	1.2	2.2	3.2	9.2	24.8	39.6
Upper bathyal rock and biogenic reef	0	0	9.4	30.5	30.5	30.5	30.5	100.0	100.0	100.0	100.0

Table 8: Landings value

Table 8. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Greater North Sea area, on landings value (presented as % of total landings value within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings value (×1000 euro)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	213.98	526474.4	1.1	3.1	5.9	9.5	14.6	21.5	31.6	45.8	65.1
Circalittoral sand	58.13	132392.4	0.3	2.1	5.4	9.1	14.0	20.4	28.1	38.5	57.6
Offshore circalittoral sand	50.93	100710.1	2.3	6.0	9.8	13.6	18.9	25.6	35.2	48.8	66.4
Offshore circalittoral mud	42.52	91552.2	2.6	5.6	8.9	13.2	19.7	27.4	37.7	51.5	70.1
Offshore circalittoral coarse sediment	19.7	99549.9	0.4	1.1	2.8	5.8	11.3	18.2	29.2	49.4	67.1
Circalittoral coarse sediment	11.56	34234.7	0.1	1.3	2.9	6.7	10.2	16.5	22.5	32.2	57.3
Infralittoral sand	8.96	26424.6	0.0	0.0	0.0	0.0	0.8	5.2	25.7	43.8	68.6
Circalittoral mud	6.41	13831.8	0.0	0.8	4.6	10.3	17.2	26.0	36.1	52.6	72.2
Circalittoral mixed sediment	4.5	4276.8	0.0	<0.1	0.4	1.7	4.8	11.0	23.2	36.7	60.7
Offshore circalittoral mixed sediment	2.95	5951.3	0.8	3.9	8.0	14.0	22.9	32.4	45.0	60.0	77.6
Upper bathyal sediment	2.48	1156.5	8.0	17.4	27.6	37.9	46.5	59.5	66.0	77.6	87.6
Infralittoral mud	1.37	2222.3	0.0	0.0	0.0	0.0	1.1	11.5	27.1	45.0	72.3
Infralittoral coarse sediment	1.23	7557	0.0	0.0	<0.1	2.9	13.0	21.6	36.0	55.3	82.6
Infralittoral mixed sediment	1.11	185.9	0.0	0.0	0.0	0.0	0.0	0.0	0.4	3.4	13.3
Unknown	0.85	3612.5	3.6	5.9	23.9	26.8	30.3	48.3	66.5	75.8	91.1
Offshore circalittoral rock and biogenic reef	0.56	1516.9	<0.1	0.5	0.8	1.8	4.0	8.6	14.2	40.5	61.1
Circalittoral rock and biogenic reef	0.42	580.6	0.0	<0.1	<0.1	0.6	2.4	4.1	8.5	23.7	36.2
Infralittoral rock and biogenic reef	0.3	718.6	0.0	<0.1	0.1	1.2	2.1	3.1	8.5	23.2	40.6
Upper bathyal rock and biogenic reef	0	0.2	9.9	33.8	33.8	33.8	33.8	100.0	100.0	100.0	100.0

Gear modifications

The effects of hypothetical gear modifications or changes in fishing practices were expressed in terms of their effects on the depletion of benthic fauna per gear pass. It was assumed that the modifications or changes in practice would achieve 5%, 10%, or 20% less depletion per gear pass. The effects of these changes in depletion on the quality and extent of the four BHTs that account for the greatest proportion of the Greater North Sea area are presented in figures 8−11. Impacts of MBCG were calculated as changes in habitat “quality” (measured as 1-PD impact or 1-PD-sens impact) in the fished area and expressed in terms of the increase in the quality of habitat meeting the extent threshold (> 75% of a BHT not adversely affected [EC, 2024]).

References:

EC. 2024. Commission Notice C/2024/2078 on the threshold values set under the Marine Strategy Framework Directive 2008/56/EC and Commission Decision (EU) 2017/848). Official Journal of the European Union C/2024/2078, 5pp. http://data.europa.eu/eli/C/2024/2078/oj

Figure 8: Habitat 1

Figure 8. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Greater North Sea area. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 9: Habitat 2

Figure 9. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Greater North Sea area. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 10: Habitat 3

Figure 10. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Greater North Sea area. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 11: Habitat 4

Figure 11. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Greater North Sea area. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Kattegat

Summary

Table 1

Table 1. Values of pressure and impact indicators for 2017‒2022 for three depth strata in the Kattegat subdivision. Values of I‒1, I‒2, I‒3, I‒4, I‒6a, I‒6b, I‒7a and I‒7b are annual means and I‒5 is evaluated over the six years. Descriptions of the pressure and impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Indicators	0 to 200 m	200 to 400 m	400 to 800 m
I‒1: Average fishing intensity	1.96	NP	NP
I‒2: Proportion of area fished, evaluated at c-square scale (%)	60.60	NP	NP
I‒3: Proportion of area fished (%)	38.20	NP	NP
I‒4: Smallest proportion of area with 90% of fishing intensity, evaluated at c-square scale (%)	26.40	NP	NP
I‒5: Proportion of area persistently unfished, evaluated at c-square scale (%)	39.40	NP	NP
I‒6a: Average PD impact	25.90	NP	NP
I‒6b: Average PD-sens impact	33.20	NP	NP
I‒7a: Proportion of area with PD impact < 0.2, evaluated at c-square scale (%)	66.20	NP	NP
I‒7b: Proportion of area with PD-sens impact < 0.2, evaluated at c-square scale (%)	63.40	NP	NP

Figure 1

Figure 1. Geographic distribution of fishing intensity (swept area ratio), seabed sensitivity (community longevity), total landings value, and total landings weight from mobile bottom-contacting gear (MBCG) in the Kattegat subdivision. The maps of swept area ratio, landings value, and landings weight show annual means evaluated at the c-square scale.

Table 2

Table 2. Contribution of small-scale fisheries (vessels < 12 m overall length) to total fishing effort (kW × fishing days) in the Kattegat subdivision. The table shows the total fishing effort (kW × fishing days) by FAO region over the assessment period, and the mean contribution (%) and observed range in contribution (%) of small-scale MBCG fisheries’.

FAO region code	FAO region name	Total fishing effort (kW × Fishing days)	Mean contribution SSF (%)	Observed range SSF contribution (%) [min - max]
27.3.a.20	Skagerrak	8589114	8.2	[6 - 11]
27.3.a.21	Kattegat	2933089	12.3	[11 - 13]
27.3.b.23	The Sound	11237	41.8	[7 - 75]

Fishing intensity

Table 3

Table 3. Extent (in km² and %) of broad habitat types in the Kattegat subdivision, and mean annual estimates of MBCG fishing intensity, landings weight, and landings value. In addition, estimates of the average annual proportion of the fished extent, the smallest proportion of the habitat extent affected by 90% of the fishing effort, and the proportion of extent persistently unfished are provided.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Relative habitat extent (%)	Landings (×1000 tonnes)	Value (×106 euro)	Swept area (×1000 km2)	Average fishing intensity (I‒1)	Average annual extent fished (%)	Smallest proportion of extent with 90% of fishing effort (%)	Percentage extent persistently unfished (%)
Offshore circalittoral mud	5.33	25.1	2.80	17.40	33.03	6.20	94.4	75.8	0.7
Infralittoral sand	4.62	21.7	0.36	0.18	0.21	0.04	3.2	6.2	77.4
Circalittoral mud	3.21	15.1	1.29	4.39	6.67	2.08	55.2	43.9	18.9
Circalittoral sand	2.94	13.8	0.36	1.00	1.66	0.56	24.9	24.7	30.1
Circalittoral mixed sediment	1.68	7.9	0.08	0.36	0.68	0.41	16.3	19.5	44.7
Infralittoral mixed sediment	1.04	4.9	0.05	0.03	0.04	0.04	3.3	18.1	63.8
Circalittoral coarse sediment	0.61	2.9	0.04	0.15	0.26	0.43	16.3	19.6	42.3
Infralittoral mud	0.52	2.4	0.94	0.23	0.03	0.06	5.6	17.3	70.8
Offshore circalittoral mixed sediment	0.42	2.0	0.11	0.73	1.39	3.29	76.4	67.4	0.7
Infralittoral coarse sediment	0.40	1.9	0.01	0.03	0.05	0.13	5.5	6.9	72.9
Offshore circalittoral sand	0.35	1.6	0.10	0.58	0.97	2.73	69.3	63.1	1.7
Offshore circalittoral coarse sediment	0.06	0.3	0.02	0.14	0.28	4.83	82.7	66.9	0.0
Infralittoral rock and biogenic reef	0.03	0.1	0.00	0.00	0.00	0.08	7.4	28.3	41.0
Circalittoral rock and biogenic reef	0.03	0.1	0.00	0.00	0.00	0.18	14.7	27.3	30.9
Offshore circalittoral rock and biogenic reef	0.01	0.0	0.00	0.01	0.02	2.56	68.1	53.4	1.7
Unknown	0.00	0.0	0.00	0.00	0.00	0.30	11.3	NA	83.7

Figure 2

Figure 2. Temporal variation of the pressure indicators I‒1, I‒3 and I‒4 in the Kattegat subdivision. Descriptions of the pressure indicators are provided in the ‘Essential Information’ Table E1 in this document.

Fishing by métier

Table 4

Table 4. Landings weight and value by métier and their relationship with swept area in the Kattegat subdivision.

	OT_CRU	OT_DMF	OT_SPF
Area swept (×1000 km2)	44.89	0.29	0.07
Landings (×1000 tonnes)	3.75	0.18	0.44
Value (×106 euro)	24.57	0.14	0.11
Landings / Area swept (kg/km2)	83.50	615.50	5981.92
Value / Area swept (euro/km2)	547.35	478.35	1541.78

Core fishing grounds

Figure 3

Figure 3. Spatial stability of core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Kattegat subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included. The numbers between brackets show the proportion of fished extent compared to the overall assessed area extent.

Figure 4

Figure 4. Spatial distribution of the stability of the core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Kattegat subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included.

Impact

Figure 5

Figure 5. The spatial distribution of MBCG fisheries impact in the Kattegat subdivision, as assessed with the PD indicator (I‒6a) and PD-sens indicator (I‒6b), shown as annual means for the assessment period, evaluated at the c-square scale. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Figure 6

Figure 6. Temporal variation in values of the PD indicator (I‒6a), PD-sens indicator (I‒6b), proportion of the extent with PD impact < 0.2 (I‒7a) and proportion of extent with PD-sens impact < 0.2 (I‒7b), shown for the overall area and for the four most extensive broad habitat types separately in the Kattegat subdivision. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Table 5

Table 5. Métier-specific landings weight and value per unit PD or PD-sens impact in the Kattegat subdivision.

	OT_CRU	OT_DMF	OT_SPF
Landings (tonnes)/PD impact	10.6	165.3	3549.7
Value (×1000 euro)/PD impact	69.3	128.4	914.9
Landings (tonnes)/PD-sens impact	8.3	97.8	2437.1
Value (×1000 euro)/PD-sens impact	54.1	76.0	628.1

Figure 7

Figure 7. Métier-related impacts, reported as annual means of the PD indicator (I‒6a, top) and PD-sens indicator (I‒6b, bottom), on the four most extensive broad habitat types in the Kattegat subdivision.

Scenarios

Footprint reduction

Table 6: Effort

Table 6. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Kattegat subdivision, on swept area (presented as % of total swept area within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total area swept (×1000 km2	10%	20%	30%	40%	50%	60%	70%	80%	90%
total	21.25	100	1.0	5.3	11.1	17.8	26.0	35.6	46.7	60.4	77.2
Offshore circalittoral mud	5.33	33.03	1.3	7.1	14.7	23.1	32.7	42.9	54.4	67.1	81.3
Infralittoral sand	4.62	0.21	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.6	5.3
Circalittoral mud	3.21	6.67	0.0	<0.1	0.1	0.8	4.9	14.4	27.1	46.1	71.8
Circalittoral sand	2.94	1.66	0.0	0.0	0.0	0.2	0.6	1.9	5.7	16.2	44.1
Circalittoral mixed sediment	1.68	0.68	0.0	0.0	0.0	0.0	0.1	0.6	2.7	9.6	32.2
Infralittoral mixed sediment	1.04	0.04	0.0	0.0	0.0	0.0	0.0	0.0	1.4	6.6	26.4
Circalittoral coarse sediment	0.61	0.26	0.0	0.0	0.0	0.0	0.2	1.7	4.6	9.2	32.6
Infralittoral mud	0.52	0.03	0.0	0.0	0.0	0.0	0.0	0.0	0.3	11.2	36.4
Offshore circalittoral mixed sediment	0.42	1.39	0.8	3.0	8.3	14.9	25.3	40.7	52.3	71.0	86.1
Infralittoral coarse sediment	0.4	0.05	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.6	6.9
Offshore circalittoral sand	0.35	0.97	0.2	0.5	3.0	12.9	23.2	28.3	40.3	59.3	81.4
Offshore circalittoral coarse sediment	0.06	0.28	0.6	2.2	8.7	18.2	28.4	41.3	51.8	67.5	90.4
Infralittoral rock and biogenic reef	0.03	0	0.0	0.0	0.0	0.0	0.5	7.1	10.7	23.7	54.3
Circalittoral rock and biogenic reef	0.03	0	0.0	0.0	0.0	0.8	1.1	2.9	11.1	38.9	65.7
Offshore circalittoral rock and biogenic reef	0.01	0.02	0.1	2.2	8.0	8.0	15.5	28.9	64.0	100.0	100.0
Unknown	0	0	10.2	10.2	10.2	10.2	100.0	100.0	100.0	100.0	100.0

Table 7: Landings weight

Table 7. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Kattegat subdivision, on landings weight (presented as % of total landings weight within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings weight (×1000 kg)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	21.25	6153.6	1.1	4.1	9.1	14.3	26.5	33.6	41.9	53.1	70.2
Offshore circalittoral mud	5.33	2803.5	2.4	8.7	18.2	26.9	36.2	46.1	57.8	70.1	84.5
Infralittoral sand	4.62	355.7	0.0	0.0	0.0	0.0	0.0	0.0	0.0	5.4	10.6
Circalittoral mud	3.21	1287.7	0.0	<0.1	2.1	4.9	40.9	49.8	58.8	70.6	85.6
Circalittoral sand	2.94	360	0.0	0.0	0.0	5.9	7.0	11.7	18.7	29.3	53.7
Circalittoral mixed sediment	1.68	83.6	0.0	0.0	0.0	0.0	0.5	5.7	13.9	25.4	51.9
Infralittoral mixed sediment	1.04	45.3	0.0	0.0	0.0	0.0	0.0	0.0	1.7	5.1	87.9
Circalittoral coarse sediment	0.61	43.6	0.0	0.0	0.0	0.0	0.3	2.1	12.3	19.9	62.8
Infralittoral mud	0.52	935.4	0.0	0.0	0.0	0.0	0.0	0.0	0.4	9.4	33.3
Offshore circalittoral mixed sediment	0.42	108.8	2.4	5.0	12.3	18.3	28.2	42.7	53.1	71.5	86.8
Infralittoral coarse sediment	0.4	10.4	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.9	5.1
Offshore circalittoral sand	0.35	97.1	0.4	1.7	6.8	18.6	27.4	33.2	45.6	61.8	79.4
Offshore circalittoral coarse sediment	0.06	20.9	1.6	5.1	12.7	20.9	30.0	41.9	51.1	64.7	91.3
Infralittoral rock and biogenic reef	0.03	0.1	0.0	0.0	0.0	0.0	1.3	6.6	9.6	25.7	56.5
Circalittoral rock and biogenic reef	0.03	0.3	0.0	0.0	0.0	1.3	1.5	2.7	12.6	41.3	70.3
Offshore circalittoral rock and biogenic reef	0.01	1.1	0.1	2.5	8.6	8.6	15.6	29.5	65.1	100.0	100.0
Unknown	0	0	9.8	9.8	9.8	9.8	100.0	100.0	100.0	100.0	100.0

Table 8: Landings value

Table 8. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Kattegat subdivision, on landings value (presented as % of total landings value within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings value (×1000 euro)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	21.25	25236.7	1.1	5.4	11.3	18.0	26.6	36.2	48.0	61.1	78.3
Offshore circalittoral mud	5.33	17395.6	1.6	7.7	15.8	24.6	34.6	45.2	57.5	69.7	84.0
Infralittoral sand	4.62	176.2	0.0	0.0	0.0	0.0	0.0	0.0	0.0	2.9	8.0
Circalittoral mud	3.21	4390.2	0.0	<0.1	0.2	1.2	7.2	15.9	29.8	47.4	72.6
Circalittoral sand	2.94	999.4	0.0	0.0	0.0	0.5	0.9	2.5	6.5	16.9	45.7
Circalittoral mixed sediment	1.68	361.1	0.0	0.0	0.0	0.0	0.1	0.8	3.3	10.3	33.9
Infralittoral mixed sediment	1.04	33.9	0.0	0.0	0.0	0.0	0.0	0.0	1.3	5.1	48.0
Circalittoral coarse sediment	0.61	153.8	0.0	0.0	0.0	0.0	0.2	1.7	4.6	10.1	34.8
Infralittoral mud	0.52	231.1	0.0	0.0	0.0	0.0	0.0	0.0	0.3	4.5	27.8
Offshore circalittoral mixed sediment	0.42	729	0.9	3.3	8.3	14.7	25.0	39.7	51.6	70.8	85.8
Infralittoral coarse sediment	0.4	30.7	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.8	6.8
Offshore circalittoral sand	0.35	579	0.2	0.6	3.8	14.1	23.3	31.3	43.0	60.7	80.2
Offshore circalittoral coarse sediment	0.06	142.8	0.9	2.9	9.3	18.2	28.4	41.2	51.2	65.5	91.1
Infralittoral rock and biogenic reef	0.03	1.2	0.0	0.0	0.0	0.0	0.8	5.5	8.1	22.9	50.6
Circalittoral rock and biogenic reef	0.03	2.4	0.0	0.0	0.0	0.8	1.0	2.3	10.9	38.7	66.0
Offshore circalittoral rock and biogenic reef	0.01	10.2	0.1	2.3	8.1	8.1	15.4	28.6	64.0	100.0	100.0
Unknown	0	0	13.7	13.7	13.7	13.7	100.0	100.0	100.0	100.0	100.0

Gear modifications

Figure 8: Habitat 1

Figure 8. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Kattegat subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 9: Habitat 2

Figure 9. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Kattegat subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 10: Habitat 3

Figure 10. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Kattegat subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 11: Habitat 4

Figure 11. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Kattegat subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Norwegian Trench

Summary

Table 1

Table 1. Values of pressure and impact indicators for 2017‒2022 for three depth strata in the Norwegian Trench subdivision. Values of I‒1, I‒2, I‒3, I‒4, I‒6a, I‒6b, I‒7a and I‒7b are annual means and I‒5 is evaluated over the six years. Descriptions of the pressure and impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Indicators	0 to 200 m	200 to 400 m	400 to 800 m
I‒1: Average fishing intensity	5.86	7.98	1.05
I‒2: Proportion of area fished, evaluated at c-square scale (%)	90.50	100.00	67.70
I‒3: Proportion of area fished (%)	79.10	97.30	40.30
I‒4: Smallest proportion of area with 90% of fishing intensity, evaluated at c-square scale (%)	54.50	72.60	27.10
I‒5: Proportion of area persistently unfished, evaluated at c-square scale (%)	9.50	0.00	32.30
I‒6a: Average PD impact	NA	NA	NA
I‒6b: Average PD-sens impact	NA	NA	NA
I‒7a: Proportion of area with PD impact < 0.2, evaluated at c-square scale (%)	NA	NA	NA
I‒7b: Proportion of area with PD-sens impact < 0.2, evaluated at c-square scale (%)	NA	NA	NA

Figure 1

Figure 1. Geographic distribution of fishing intensity (swept area ratio), seabed sensitivity (community longevity), total landings value, and total landings weight from mobile bottom-contacting gear (MBCG) in the Norwegian Trench subdivision. The maps of swept area ratio, landings value, and landings weight show annual means evaluated at the c-square scale.

Table 2

Table 2. Contribution of small-scale fisheries (vessels < 12 m overall length) to total fishing effort (kW × fishing days) in the Norwegian Trench subdivision. The table shows the total fishing effort (kW × fishing days) by FAO region over the assessment period, and the mean contribution (%) and observed range in contribution (%) of small-scale MBCG fisheries’.

FAO region code	FAO region name	Total fishing effort (kW × Fishing days)	Mean contribution SSF (%)	Observed range SSF contribution (%) [min - max]
27.3.a.20	Skagerrak	8589114	8.2	[6 - 11]
27.4.a	Northern North Sea	6518051	0.0	[0 - 0]

Fishing intensity

Table 3

Table 3. Extent (in km² and %) of broad habitat types in the Norwegian Trench subdivision, and mean annual estimates of MBCG fishing intensity, landings weight, and landings value. In addition, estimates of the average annual proportion of the fished extent, the smallest proportion of the habitat extent affected by 90% of the fishing effort, and the proportion of extent persistently unfished are provided.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Relative habitat extent (%)	Landings (×1000 tonnes)	Value (×106 euro)	Swept area (×1000 km2)	Average fishing intensity (I‒1)	Average annual extent fished (%)	Smallest proportion of extent with 90% of fishing effort (%)	Percentage extent persistently unfished (%)
Offshore circalittoral mud	4.58	50.6	4.67	20.62	34.81	7.61	96.0	71.2	0.9
Upper bathyal sediment	2.48	27.4	2.48	12.60	15.51	6.27	83.4	62.5	7.9
Offshore circalittoral mixed sediment	0.86	9.5	0.16	1.52	2.05	2.40	70.4	58.2	2.7
Offshore circalittoral rock and biogenic reef	0.29	3.2	0.07	0.64	0.76	2.58	62.5	47.2	3.4
Circalittoral rock and biogenic reef	0.23	2.5	0.02	0.15	0.16	0.71	23.5	20.1	26.0
Offshore circalittoral sand	0.21	2.3	0.40	0.95	2.78	13.24	95.3	75.6	0.1
Circalittoral mud	0.13	1.4	0.02	0.06	0.14	1.10	13.8	7.3	72.8
Infralittoral rock and biogenic reef	0.11	1.2	0.01	0.06	0.06	0.51	18.0	13.7	35.1
Infralittoral mud	0.06	0.7	0.00	0.01	0.01	0.11	4.5	4.4	88.3
Circalittoral mixed sediment	0.04	0.4	0.00	0.01	0.01	0.21	10.2	31.0	39.6
Offshore circalittoral coarse sediment	0.02	0.2	0.00	0.02	0.02	1.09	44.4	32.8	1.9
Circalittoral coarse sediment	0.02	0.2	0.00	0.02	0.02	1.04	28.2	22.9	3.2
Circalittoral sand	0.02	0.2	0.01	0.03	0.07	4.27	55.7	41.7	3.7
Infralittoral sand	0.01	0.1	0.01	0.03	0.08	7.44	68.3	46.8	2.4
Infralittoral mixed sediment	0.00	0.0	0.00	0.00	0.00	0.04	2.0	6.9	86.5
Unknown	0.00	0.0	0.00	0.00	0.00	0.47	10.2	6.2	67.2
Infralittoral coarse sediment	0.00	0.0	0.00	0.01	0.01	2.95	54.7	40.2	11.3
Upper bathyal rock and biogenic reef	0.00	0.0	0.00	0.00	0.00	4.04	98.2	NA	0.0

Figure 2

Figure 2. Temporal variation of the pressure indicators I‒1, I‒3 and I‒4 in the Norwegian Trench subdivision. Descriptions of the pressure indicators are provided in the ‘Essential Information’ Table E1 in this document.

Fishing by métier

Table 4

Table 4. Landings weight and value by métier and their relationship with swept area in the Norwegian Trench subdivision.

	OT_CRU	OT_DMF	SDN_DMF	OT_SPF
Area swept (×1000 km2)	46.11	6.52	3.33	0.03
Landings (×1000 tonnes)	5.95	1.49	0.32	0.03
Value (×106 euro)	32.21	3.52	0.85	0.02
Landings / Area swept (kg/km2)	129.01	229.02	96.42	985.19
Value / Area swept (euro/km2)	698.59	540.19	253.63	759.60

Core fishing grounds

Figure 3

Figure 3. Spatial stability of core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Norwegian Trench subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included. The numbers between brackets show the proportion of fished extent compared to the overall assessed area extent.

Figure 4

Figure 4. Spatial distribution of the stability of the core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Norwegian Trench subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included.

Impact

This region does not allow for impact assessments, due to lacking sensitivity estimates.

Scenarios

Footprint reduction

Table 6: Effort

Table 6. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Norwegian Trench subdivision, on swept area (presented as % of total swept area within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total area swept (×1000 km2	10%	20%	30%	40%	50%	60%	70%	80%	90%
total	9.06	100	1.1	4.3	9.2	16.5	25.3	34.9	46.7	60.6	77.3
Offshore circalittoral mud	4.58	34.81	1.7	5.7	11.1	18.4	27.1	36.5	47.9	61.6	78.1
Upper bathyal sediment	2.48	15.51	<0.1	1.1	5.4	12.4	21.7	32.1	44.0	57.2	75.2
Offshore circalittoral mixed sediment	0.86	2.05	0.2	1.8	3.5	9.4	15.9	27.2	43.3	60.9	78.4
Offshore circalittoral rock and biogenic reef	0.29	0.76	<0.1	0.4	1.1	4.2	8.3	19.1	34.5	49.7	67.9
Circalittoral rock and biogenic reef	0.23	0.16	0.0	0.0	<0.1	0.4	1.7	3.1	5.4	11.9	42.4
Offshore circalittoral sand	0.21	2.78	1.4	8.6	16.4	26.9	39.4	45.7	60.3	78.4	88.0
Circalittoral mud	0.13	0.14	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.9	7.3
Infralittoral rock and biogenic reef	0.11	0.06	0.0	0.0	0.0	<0.1	0.4	1.2	3.8	5.1	29.3
Infralittoral mud	0.06	0.01	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.8
Circalittoral mixed sediment	0.04	0.01	0.0	0.0	0.0	0.1	1.9	3.4	12.1	21.4	52.3
Offshore circalittoral coarse sediment	0.02	0.02	<0.1	0.3	4.0	5.5	5.5	7.3	29.5	44.6	64.0
Circalittoral coarse sediment	0.02	0.02	<0.1	0.3	0.4	0.4	1.8	3.5	7.1	17.6	52.9
Circalittoral sand	0.02	0.07	<0.1	<0.1	0.3	0.7	3.9	36.3	36.3	62.6	100.0
Infralittoral sand	0.01	0.08	<0.1	<0.1	<0.1	6.1	14.2	30.2	30.2	59.4	100.0
Infralittoral mixed sediment	0	0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	5.9
Unknown	0	0	0.0	0.0	0.0	0.0	0.0	0.0	<0.1	0.7	5.0
Infralittoral coarse sediment	0	0.01	0.0	<0.1	<0.1	<0.1	17.8	52.5	52.5	52.5	100.0
Upper bathyal rock and biogenic reef	0	0	14.3	42.1	42.1	60.7	80.2	80.2	80.2	80.2	100.0

Table 7: Landings weight

Table 7. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Norwegian Trench subdivision, on landings weight (presented as % of total landings weight within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings weight (×1000 kg)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	9.06	7840.4	0.9	3.4	8.2	15.4	24.1	33.4	45.1	58.6	75.9
Offshore circalittoral mud	4.58	4669	1.3	4.3	9.1	16.3	24.4	33.2	44.2	57.1	74.3
Upper bathyal sediment	2.48	2483.4	<0.1	1.0	5.3	11.7	21.3	31.9	44.7	58.5	77.6
Offshore circalittoral mixed sediment	0.86	160.3	0.2	1.9	3.6	10.0	16.7	28.7	41.6	60.6	76.9
Offshore circalittoral rock and biogenic reef	0.29	67	<0.1	0.5	1.2	4.4	7.8	17.6	32.0	44.8	62.7
Circalittoral rock and biogenic reef	0.23	15.6	0.0	0.0	<0.1	0.3	1.9	3.0	5.2	11.0	38.1
Offshore circalittoral sand	0.21	396.7	1.4	10.8	19.8	34.5	47.2	54.3	66.7	82.7	91.2
Circalittoral mud	0.13	16.1	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.8	7.5
Infralittoral rock and biogenic reef	0.11	6	0.0	0.0	0.0	<0.1	0.3	1.0	3.4	5.0	24.8
Infralittoral mud	0.06	0.8	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.7
Circalittoral mixed sediment	0.04	0.6	0.0	0.0	0.0	0.1	1.8	3.0	14.5	25.4	58.9
Offshore circalittoral coarse sediment	0.02	2	<0.1	0.3	4.9	6.7	6.7	8.6	32.6	47.0	66.5
Circalittoral coarse sediment	0.02	2.5	<0.1	0.2	0.3	0.3	1.2	2.4	5.5	17.2	53.5
Circalittoral sand	0.02	9	<0.1	<0.1	0.2	0.5	2.8	30.9	30.9	62.5	100.0
Infralittoral sand	0.01	9.5	<0.1	<0.1	<0.1	5.4	15.7	31.7	31.7	63.0	100.0
Infralittoral mixed sediment	0	0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	5.9
Unknown	0	0.2	0.0	0.0	0.0	0.0	0.0	0.0	<0.1	0.6	6.8
Infralittoral coarse sediment	0	1.2	0.0	<0.1	<0.1	<0.1	18.0	53.5	53.5	53.5	100.0
Upper bathyal rock and biogenic reef	0	0.4	12.5	38.9	38.9	59.7	77.6	77.6	77.6	77.6	100.0

Table 8: Landings value

Table 8. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Norwegian Trench subdivision, on landings value (presented as % of total landings value within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings value (×1000 euro)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	9.06	36738.5	1.4	4.5	9.7	18.1	27.9	39.0	51.2	64.9	81.1
Offshore circalittoral mud	4.58	20616.7	2.3	6.6	12.3	21.5	31.3	42.2	53.4	66.1	81.2
Upper bathyal sediment	2.48	12599.9	<0.1	1.2	6.2	13.7	24.1	36.1	49.8	64.6	82.8
Offshore circalittoral mixed sediment	0.86	1521.3	0.1	1.7	3.5	10.0	17.6	28.9	42.4	60.5	76.8
Offshore circalittoral rock and biogenic reef	0.29	638.9	<0.1	0.5	1.2	4.2	7.7	18.0	32.8	46.3	65.2
Circalittoral rock and biogenic reef	0.23	148.6	0.0	0.0	<0.1	0.3	2.1	3.2	5.2	10.7	39.4
Offshore circalittoral sand	0.21	950.8	2.6	9.8	17.7	30.1	45.3	50.7	63.2	80.7	90.0
Circalittoral mud	0.13	64	0.0	0.0	0.0	0.0	0.0	0.0	0.0	2.0	20.1
Infralittoral rock and biogenic reef	0.11	60.2	0.0	0.0	0.0	<0.1	0.3	1.0	3.3	4.9	24.4
Infralittoral mud	0.06	8.6	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.5
Circalittoral mixed sediment	0.04	5.8	0.0	0.0	0.0	<0.1	1.8	2.8	14.3	24.7	58.0
Offshore circalittoral coarse sediment	0.02	19.5	<0.1	0.3	4.9	6.7	6.7	8.6	32.7	48.6	71.4
Circalittoral coarse sediment	0.02	24.5	<0.1	0.2	0.2	0.2	1.1	2.3	5.4	17.0	54.3
Circalittoral sand	0.02	33.6	<0.1	0.1	0.6	1.3	8.0	53.4	53.4	71.8	100.0
Infralittoral sand	0.01	29.1	<0.1	0.2	0.2	17.9	25.2	40.7	40.7	69.0	100.0
Infralittoral mixed sediment	0	0.2	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	5.8
Unknown	0	1.8	0.0	0.0	0.0	0.0	0.0	0.0	<0.1	0.7	10.4
Infralittoral coarse sediment	0	12.3	0.0	<0.1	<0.1	<0.1	19.3	54.7	54.7	54.7	100.0
Upper bathyal rock and biogenic reef	0	2.8	15.5	42.4	42.4	61.7	79.6	79.6	79.6	79.6	100.0

Gear modifications

This region does not allow for the gear modifications scenario, due to lacking sensitivity estimates.

Central North Sea

Summary

Table 1

Table 1. Values of pressure and impact indicators for 2017‒2022 for three depth strata in the Central North Sea subdivision. Values of I‒1, I‒2, I‒3, I‒4, I‒6a, I‒6b, I‒7a and I‒7b are annual means and I‒5 is evaluated over the six years. Descriptions of the pressure and impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Indicators	0 to 200 m	200 to 400 m	400 to 800 m
I‒1: Average fishing intensity	4.24	NP	NP
I‒2: Proportion of area fished, evaluated at c-square scale (%)	99.90	NP	NP
I‒3: Proportion of area fished (%)	81.70	NP	NP
I‒4: Smallest proportion of area with 90% of fishing intensity, evaluated at c-square scale (%)	41.20	NP	NP
I‒5: Proportion of area persistently unfished, evaluated at c-square scale (%)	0.10	NP	NP
I‒6a: Average PD impact	27.10	NP	NP
I‒6b: Average PD-sens impact	36.10	NP	NP
I‒7a: Proportion of area with PD impact < 0.2, evaluated at c-square scale (%)	63.50	NP	NP
I‒7b: Proportion of area with PD-sens impact < 0.2, evaluated at c-square scale (%)	53.50	NP	NP

Figure 1

Figure 1. Geographic distribution of fishing intensity (swept area ratio), seabed sensitivity (community longevity), total landings value, and total landings weight from mobile bottom-contacting gear (MBCG) in the Central North Sea subdivision. The maps of swept area ratio, landings value, and landings weight show annual means evaluated at the c-square scale.

Table 2

Table 2. Contribution of small-scale fisheries (vessels < 12 m overall length) to total fishing effort (kW × fishing days) in the Central North Sea subdivision. The table shows the total fishing effort (kW × fishing days) by FAO region over the assessment period, and the mean contribution (%) and observed range in contribution (%) of small-scale MBCG fisheries’.

FAO region code	FAO region name	Total fishing effort (kW × Fishing days)	Mean contribution SSF (%)	Observed range SSF contribution (%) [min - max]
27.3.a.20	Skagerrak	8589114	8.2	[6 - 11]
27.4.a	Northern North Sea	6518051	0.0	[0 - 0]
27.4.b	Central North Sea	24194203	1.0	[1 - 1]

Fishing intensity

Table 3

Table 3. Extent (in km² and %) of broad habitat types in the Central North Sea subdivision, and mean annual estimates of MBCG fishing intensity, landings weight, and landings value. In addition, estimates of the average annual proportion of the fished extent, the smallest proportion of the habitat extent affected by 90% of the fishing effort, and the proportion of extent persistently unfished are provided.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Relative habitat extent (%)	Landings (×1000 tonnes)	Value (×106 euro)	Swept area (×1000 km2)	Average fishing intensity (I‒1)	Average annual extent fished (%)	Smallest proportion of extent with 90% of fishing effort (%)	Percentage extent persistently unfished (%)
Offshore circalittoral mud	8.34	43.9	4.54	12.22	26.31	3.16	78.4	49.4	0.0
Offshore circalittoral sand	6.54	34.4	18.43	22.74	41.56	6.36	85.6	48.7	0.3
Circalittoral sand	1.68	8.8	10.02	5.17	6.66	3.96	94.6	64.6	0.0
Offshore circalittoral mixed sediment	1.16	6.1	1.32	2.83	3.36	2.90	77.4	57.1	0.0
Offshore circalittoral coarse sediment	0.59	3.1	1.26	1.11	1.03	1.73	67.4	66.2	0.0
Circalittoral coarse sediment	0.33	1.7	0.64	0.54	0.47	1.43	80.4	78.5	0.0
Circalittoral mixed sediment	0.30	1.6	0.34	0.64	0.87	2.87	60.4	44.3	0.0
Infralittoral sand	0.03	0.2	0.98	0.33	0.24	7.49	100.0	NA	0.0
Circalittoral mud	0.02	0.1	0.02	0.03	0.07	3.54	85.3	NA	0.0
Infralittoral coarse sediment	0.00	0.0	0.00	0.00	0.00	14.68	100.0	NA	0.0

Figure 2

Figure 2. Temporal variation of the pressure indicators I‒1, I‒3 and I‒4 in the Central North Sea subdivision. Descriptions of the pressure indicators are provided in the ‘Essential Information’ Table E1 in this document.

Fishing by métier

Table 4

Table 4. Landings weight and value by métier and their relationship with swept area in the Central North Sea subdivision.

	OT_CRU	OT_DMF	SDN_DMF	SSC_DMF	TBB_DMF	OT_SPF
Area swept (×1000 km2)	27.01	26.58	16.46	5.48	4.98	0.07
Landings (×1000 tonnes)	3.33	27.37	1.59	0.59	4.04	0.62
Value (×106 euro)	13.75	15.84	4.09	1.55	10.18	0.19
Landings / Area swept (kg/km2)	123.44	1029.84	96.70	108.47	811.82	9462.14
Value / Area swept (euro/km2)	509.01	595.99	248.71	283.37	2043.89	2910.54

Core fishing grounds

Figure 3

Figure 3. Spatial stability of core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Central North Sea subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included. The numbers between brackets show the proportion of fished extent compared to the overall assessed area extent.

Figure 4

Figure 4. Spatial distribution of the stability of the core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Central North Sea subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included.

Impact

Figure 5

Figure 5. The spatial distribution of MBCG fisheries impact in the Central North Sea subdivision, as assessed with the PD indicator (I‒6a) and PD-sens indicator (I‒6b), shown as annual means for the assessment period, evaluated at the c-square scale. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Figure 6

Figure 6. Temporal variation in values of the PD indicator (I‒6a), PD-sens indicator (I‒6b), proportion of the extent with PD impact < 0.2 (I‒7a) and proportion of extent with PD-sens impact < 0.2 (I‒7b), shown for the overall area and for the four most extensive broad habitat types separately in the Central North Sea subdivision. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Table 5

Table 5. Métier-specific landings weight and value per unit PD or PD-sens impact in the Central North Sea subdivision.

	OT_CRU	OT_DMF	SDN_DMF	SSC_DMF	TBB_DMF	OT_SPF
Landings (tonnes)/PD impact	18.8	343.8	69.8	48.1	54.1	7520.5
Value (×1000 euro)/PD impact	77.6	198.9	179.5	125.7	136.2	2313.3
Landings (tonnes)/PD-sens impact	14.8	205.2	40.5	28.0	33.4	4980.8
Value (×1000 euro)/PD-sens impact	61.0	118.7	104.2	73.2	84.0	1532.1

Figure 7

Figure 7. Métier-related impacts, reported as annual means of the PD indicator (I‒6a, top) and PD-sens indicator (I‒6b, bottom), on the four most extensive broad habitat types in the Central North Sea subdivision.

Scenarios

Footprint reduction

Table 6: Effort

Table 6. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Central North Sea subdivision, on swept area (presented as % of total swept area within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total area swept (×1000 km2	10%	20%	30%	40%	50%	60%	70%	80%	90%
total	18.99	100	1.1	2.6	4.5	7.0	10.6	15.4	22.5	33.8	55.5
Offshore circalittoral mud	8.34	26.31	1.3	3.0	4.9	7.3	9.9	12.7	16.1	21.1	42.6
Offshore circalittoral sand	6.54	41.56	0.5	1.6	2.9	5.1	9.4	15.1	23.5	38.5	60.9
Circalittoral sand	1.68	6.66	2.5	4.8	8.2	12.1	15.8	22.2	38.1	50.2	68.8
Offshore circalittoral mixed sediment	1.16	3.36	2.1	3.9	6.8	9.4	12.5	16.6	21.9	33.6	56.9
Offshore circalittoral coarse sediment	0.59	1.03	3.2	6.0	9.6	12.0	14.9	21.7	30.0	45.2	69.4
Circalittoral coarse sediment	0.33	0.47	4.3	10.2	17.6	24.7	30.8	41.2	49.7	62.0	72.4
Circalittoral mixed sediment	0.3	0.87	1.9	3.8	5.0	6.8	9.3	11.5	13.6	17.1	48.1
Infralittoral sand	0.03	0.24	15.0	23.5	33.0	51.1	51.1	72.4	72.4	100.0	100.0
Circalittoral mud	0.02	0.07	7.0	10.6	17.3	22.2	22.2	35.7	35.7	35.7	35.7
Infralittoral coarse sediment	0	0	100.0	100.0	100.0	100.0	100.0	100.0	100.0	100.0	100.0

Table 7: Landings weight

Table 7. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Central North Sea subdivision, on landings weight (presented as % of total landings weight within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings weight (×1000 kg)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	18.99	37554.7	1.8	3.8	6.2	10.5	16.5	29.6	45.8	65.9	78.2
Offshore circalittoral mud	8.34	4541.5	2.6	5.1	8.3	13.7	18.3	22.3	30.3	44.1	62.2
Offshore circalittoral sand	6.54	18428.4	0.7	2.4	4.4	8.7	17.0	37.1	57.9	82.2	89.6
Circalittoral sand	1.68	10024	1.3	2.1	3.1	6.2	9.5	14.9	30.7	48.6	66.8
Offshore circalittoral mixed sediment	1.16	1321.9	3.6	7.6	14.2	20.7	28.2	37.2	49.9	66.9	84.4
Offshore circalittoral coarse sediment	0.59	1263.1	2.9	5.8	8.7	10.2	12.3	17.9	21.1	30.1	50.6
Circalittoral coarse sediment	0.33	638.1	4.2	7.8	15.1	17.3	23.6	39.1	48.6	51.7	53.1
Circalittoral mixed sediment	0.3	341.4	4.4	10.6	14.5	18.2	23.1	26.8	31.6	40.0	69.5
Infralittoral sand	0.03	979.6	18.0	28.5	37.6	53.5	53.5	73.4	73.4	100.0	100.0
Circalittoral mud	0.02	16.8	8.1	11.3	17.7	25.6	25.6	62.1	62.1	62.1	62.1
Infralittoral coarse sediment	0	0	100.0	100.0	100.0	100.0	100.0	100.0	100.0	100.0	100.0

Table 8: Landings value

Table 8. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Central North Sea subdivision, on landings value (presented as % of total landings value within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings value (×1000 euro)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	18.99	45609.2	1.8	4.2	7.0	10.8	16.2	23.9	33.8	47.0	65.7
Offshore circalittoral mud	8.34	12218.1	1.4	3.0	4.7	7.1	9.7	12.3	15.6	21.2	42.1
Offshore circalittoral sand	6.54	22736.7	1.0	3.1	5.7	9.7	16.5	26.8	39.5	56.5	74.4
Circalittoral sand	1.68	5167.3	3.1	5.2	8.0	11.7	15.3	21.3	36.0	50.6	70.6
Offshore circalittoral mixed sediment	1.16	2830.8	3.3	7.5	13.1	17.6	27.0	36.0	45.7	59.6	78.5
Offshore circalittoral coarse sediment	0.59	1112.4	6.5	12.1	17.8	22.2	28.2	37.2	45.6	56.3	72.9
Circalittoral coarse sediment	0.33	536.8	6.9	17.4	26.1	32.0	41.1	57.3	65.1	71.3	75.4
Circalittoral mixed sediment	0.3	639.1	5.7	11.6	16.5	21.9	28.2	33.4	39.9	48.5	74.0
Infralittoral sand	0.03	334.1	15.6	24.1	33.2	50.3	50.3	71.1	71.1	100.0	100.0
Circalittoral mud	0.02	33.8	7.0	10.5	17.4	24.8	24.8	47.5	47.5	47.5	47.5
Infralittoral coarse sediment	0	0	100.0	100.0	100.0	100.0	100.0	100.0	100.0	100.0	100.0

Gear modifications

Figure 8: Habitat 1

Figure 8. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Central North Sea subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 9: Habitat 2

Figure 9. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Central North Sea subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 10: Habitat 3

Figure 10. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Central North Sea subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 11: Habitat 4

Figure 11. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Central North Sea subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Southern North Sea

Summary

Table 1

Table 1. Values of pressure and impact indicators for 2017‒2022 for three depth strata in the Southern North Sea subdivision. Values of I‒1, I‒2, I‒3, I‒4, I‒6a, I‒6b, I‒7a and I‒7b are annual means and I‒5 is evaluated over the six years. Descriptions of the pressure and impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Indicators	0 to 200 m	200 to 400 m	400 to 800 m
I‒1: Average fishing intensity	1.77	NP	NP
I‒2: Proportion of area fished, evaluated at c-square scale (%)	98.60	NP	NP
I‒3: Proportion of area fished (%)	74.00	NP	NP
I‒4: Smallest proportion of area with 90% of fishing intensity, evaluated at c-square scale (%)	56.50	NP	NP
I‒5: Proportion of area persistently unfished, evaluated at c-square scale (%)	1.40	NP	NP
I‒6a: Average PD impact	14.40	NP	NP
I‒6b: Average PD-sens impact	22.60	NP	NP
I‒7a: Proportion of area with PD impact < 0.2, evaluated at c-square scale (%)	73.60	NP	NP
I‒7b: Proportion of area with PD-sens impact < 0.2, evaluated at c-square scale (%)	58.50	NP	NP

Figure 1

Figure 1. Geographic distribution of fishing intensity (swept area ratio), seabed sensitivity (community longevity), total landings value, and total landings weight from mobile bottom-contacting gear (MBCG) in the Southern North Sea subdivision. The maps of swept area ratio, landings value, and landings weight show annual means evaluated at the c-square scale.

Table 2

Table 2. Contribution of small-scale fisheries (vessels < 12 m overall length) to total fishing effort (kW × fishing days) in the Southern North Sea subdivision. The table shows the total fishing effort (kW × fishing days) by FAO region over the assessment period, and the mean contribution (%) and observed range in contribution (%) of small-scale MBCG fisheries’.

FAO region code	FAO region name	Total fishing effort (kW × Fishing days)	Mean contribution SSF (%)	Observed range SSF contribution (%) [min - max]
27.3.a.20	Skagerrak	8589114	8.2	[6 - 11]
27.4.b	Central North Sea	24194203	1.0	[1 - 1]
27.4.c	Southern North Sea	19239402	0.0	[0 - 0]
27.7.e	Eastern English Channel	8267271	32.8	[31 - 35]

Fishing intensity

Table 3

Table 3. Extent (in km² and %) of broad habitat types in the Southern North Sea subdivision, and mean annual estimates of MBCG fishing intensity, landings weight, and landings value. In addition, estimates of the average annual proportion of the fished extent, the smallest proportion of the habitat extent affected by 90% of the fishing effort, and the proportion of extent persistently unfished are provided.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Relative habitat extent (%)	Landings (×1000 tonnes)	Value (×106 euro)	Swept area (×1000 km2)	Average fishing intensity (I‒1)	Average annual extent fished (%)	Smallest proportion of extent with 90% of fishing effort (%)	Percentage extent persistently unfished (%)
Circalittoral sand	51.22	36.8	67.15	114.97	87.33	1.70	69.8	55.9	1.8
Offshore circalittoral sand	42.53	30.5	32.12	62.05	61.11	1.44	77.1	70.9	0.2
Offshore circalittoral mud	24.24	17.4	23.89	41.65	56.17	2.32	89.4	69.1	0.1
Circalittoral coarse sediment	6.92	5.0	9.97	10.37	8.66	1.25	58.4	56.7	1.3
Offshore circalittoral coarse sediment	3.52	2.5	4.94	11.44	15.65	4.45	82.9	55.3	0.5
Infralittoral sand	3.37	2.4	11.64	23.34	8.26	2.45	70.7	56.2	7.8
Circalittoral mud	2.88	2.1	10.04	10.30	4.95	1.72	66.0	64.0	2.3
Circalittoral mixed sediment	2.48	1.8	3.72	3.46	2.66	1.07	51.7	52.8	1.6
Unknown	0.85	0.6	1.45	3.63	3.28	3.85	90.9	66.2	0.1
Infralittoral mud	0.60	0.4	6.23	3.08	0.21	0.36	18.3	33.0	31.4
Offshore circalittoral mixed sediment	0.42	0.3	0.45	0.83	0.64	1.53	69.7	69.1	0.8
Infralittoral coarse sediment	0.11	0.1	0.69	0.71	0.28	2.54	78.1	61.3	0.2
Infralittoral mixed sediment	0.06	0.0	0.55	0.21	0.02	0.40	13.8	16.4	14.7
Offshore circalittoral rock and biogenic reef	0.04	0.0	0.00	0.01	0.01	0.18	8.4	10.3	31.1
Circalittoral rock and biogenic reef	0.04	0.0	0.00	0.01	0.01	0.28	16.2	12.8	34.4
Infralittoral rock and biogenic reef	0.00	0.0	0.00	0.00	0.00	0.04	3.8	NA	1.2

Figure 2

Figure 2. Temporal variation of the pressure indicators I‒1, I‒3 and I‒4 in the Southern North Sea subdivision. Descriptions of the pressure indicators are provided in the ‘Essential Information’ Table E1 in this document.

Fishing by métier

Table 4

Table 4. Landings weight and value by métier and their relationship with swept area in the Southern North Sea subdivision.

	TBB_DMF	OT_DMF	TBB_CRU	OT_CRU	SSC_DMF	SDN_DMF	OT_MI	OT_SPF	DRB_MOL
Area swept (×1000 km2)	59.37	53.77	48.16	40.22	31.77	16.06	1.88	1.59	0.44
Landings (×1000 tonnes)	26.26	61.71	22.26	5.07	2.45	1.60	0.96	26.25	26.29
Value (×106 euro)	107.42	29.05	91.15	20.60	5.10	4.09	3.36	6.43	18.84
Landings / Area swept (kg/km2)	442.27	1147.70	462.21	126.18	76.97	99.46	507.98	16528.20	59965.79
Value / Area swept (euro/km2)	1809.42	540.33	1892.75	512.26	160.58	254.45	1784.76	4046.66	42969.46

Core fishing grounds

Figure 3

Figure 3. Spatial stability of core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Southern North Sea subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included. The numbers between brackets show the proportion of fished extent compared to the overall assessed area extent.

Figure 4

Figure 4. Spatial distribution of the stability of the core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Southern North Sea subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included.

Impact

Figure 5

Figure 5. The spatial distribution of MBCG fisheries impact in the Southern North Sea subdivision, as assessed with the PD indicator (I‒6a) and PD-sens indicator (I‒6b), shown as annual means for the assessment period, evaluated at the c-square scale. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Figure 6

Figure 6. Temporal variation in values of the PD indicator (I‒6a), PD-sens indicator (I‒6b), proportion of the extent with PD impact < 0.2 (I‒7a) and proportion of extent with PD-sens impact < 0.2 (I‒7b), shown for the overall area and for the four most extensive broad habitat types separately in the Southern North Sea subdivision. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Table 5

Table 5. Métier-specific landings weight and value per unit PD or PD-sens impact in the Southern North Sea subdivision.

	TBB_DMF	OT_DMF	TBB_CRU	OT_CRU	SSC_DMF	SDN_DMF	OT_MI	OT_SPF	DRB_MOL
Landings (tonnes)/PD impact	46.3	456.0	106.9	17.4	71.9	56.1	117.7	9692.2	570.0
Value (×1000 euro)/PD impact	189.3	214.7	437.7	70.5	150.0	143.6	413.5	2373.0	408.4
Landings (tonnes)/PD-sens impact	29.2	290.6	73.0	11.5	46.2	39.3	77.7	7952.5	546.4
Value (×1000 euro)/PD-sens impact	119.3	136.8	298.9	46.7	96.3	100.5	273.0	1947.0	391.5

Figure 7

Figure 7. Métier-related impacts, reported as annual means of the PD indicator (I‒6a, top) and PD-sens indicator (I‒6b, bottom), on the four most extensive broad habitat types in the Southern North Sea subdivision.

Scenarios

Footprint reduction

Table 6: Effort

Table 6. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Southern North Sea subdivision, on swept area (presented as % of total swept area within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total area swept (×1000 km2	10%	20%	30%	40%	50%	60%	70%	80%	90%
total	139.28	100	1.3	3.8	7.2	11.8	17.7	25.3	34.8	47.0	63.7
Circalittoral sand	51.22	87.33	0.2	1.4	4.0	8.0	13.6	21.0	30.3	42.0	59.5
Offshore circalittoral sand	42.53	61.11	2.1	6.1	10.5	15.7	21.9	29.7	39.3	51.3	65.9
Offshore circalittoral mud	24.24	56.17	2.5	5.7	9.6	14.9	21.3	28.9	38.6	51.2	69.3
Circalittoral coarse sediment	6.92	8.66	0.3	1.7	4.2	7.9	14.4	21.4	31.7	45.5	61.5
Offshore circalittoral coarse sediment	3.52	15.65	0.7	2.2	4.8	8.1	12.2	17.4	24.4	34.7	49.5
Infralittoral sand	3.37	8.26	0.4	2.5	6.8	12.5	20.7	32.7	43.9	57.8	73.8
Circalittoral mud	2.88	4.95	2.1	5.1	9.8	13.7	19.3	25.8	34.5	44.3	66.0
Circalittoral mixed sediment	2.48	2.66	0.2	1.2	3.4	7.1	13.2	19.0	26.6	42.2	64.2
Unknown	0.85	3.28	2.7	5.1	9.1	12.4	16.7	28.1	44.6	63.8	83.5
Infralittoral mud	0.6	0.21	0.0	0.0	0.2	2.9	10.0	13.1	22.7	38.8	70.3
Offshore circalittoral mixed sediment	0.42	0.64	1.6	4.2	9.7	12.8	19.0	32.0	48.3	56.2	65.7
Infralittoral coarse sediment	0.11	0.28	1.0	5.9	7.6	12.3	24.4	41.2	55.0	66.9	75.6
Infralittoral mixed sediment	0.06	0.02	0.0	0.3	0.5	1.7	1.7	6.8	6.8	24.5	67.5
Offshore circalittoral rock and biogenic reef	0.04	0.01	0.0	0.0	0.0	<0.1	0.3	1.4	3.5	4.2	23.6
Circalittoral rock and biogenic reef	0.04	0.01	0.0	0.0	0.0	<0.1	0.4	0.5	1.2	1.6	58.0

Table 7: Landings weight

Table 7. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Southern North Sea subdivision, on landings weight (presented as % of total landings weight within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings weight (×1000 kg)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	139.28	155966.8	3.0	7.9	13.4	19.4	25.3	32.6	41.0	51.1	66.1
Circalittoral sand	51.22	66374.5	0.5	2.5	6.0	8.8	12.9	19.3	26.7	37.3	56.4
Offshore circalittoral sand	42.53	32121	5.3	12.6	18.8	25.1	32.8	42.0	51.0	61.3	72.6
Offshore circalittoral mud	24.24	23888.7	8.6	19.0	28.5	37.5	46.0	53.8	63.4	72.7	83.1
Circalittoral coarse sediment	6.92	9927.2	0.3	2.0	3.7	9.8	14.0	17.8	25.7	34.7	50.5
Offshore circalittoral coarse sediment	3.52	4934.3	1.7	5.2	10.4	15.9	23.6	32.6	44.8	58.6	73.9
Infralittoral sand	3.37	8745.2	2.0	10.1	16.2	36.6	43.5	51.6	59.1	67.0	77.7
Circalittoral mud	2.88	3631.1	5.8	14.1	23.4	33.7	41.4	46.9	53.7	62.0	83.0
Circalittoral mixed sediment	2.48	3476.5	0.4	1.5	3.0	5.9	11.9	16.3	22.0	33.1	47.2
Unknown	0.85	1424.6	4.8	8.3	37.5	43.2	46.5	61.4	75.1	81.9	93.0
Infralittoral mud	0.6	298	0.0	0.0	2.3	12.2	29.4	40.0	56.0	72.8	90.6
Offshore circalittoral mixed sediment	0.42	445.3	3.7	10.1	28.4	31.6	34.4	49.0	65.4	74.3	79.9
Infralittoral coarse sediment	0.11	676.3	0.8	12.4	30.9	33.0	36.2	54.2	66.5	68.7	70.0
Infralittoral mixed sediment	0.06	17.9	0.0	0.2	0.2	2.8	2.8	4.2	4.2	20.0	70.7
Offshore circalittoral rock and biogenic reef	0.04	3.1	0.0	0.0	0.0	<0.1	<0.1	37.9	38.9	39.2	51.2
Circalittoral rock and biogenic reef	0.04	3.2	0.0	0.0	0.0	<0.1	1.7	1.7	1.8	1.9	62.5

Table 8: Landings value

Table 8. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Southern North Sea subdivision, on landings value (presented as % of total landings value within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings value (×1000 euro)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	139.28	277087.1	2.0	5.7	10.3	15.8	21.9	29.7	39.0	50.9	68.1
Circalittoral sand	51.22	112946.3	0.5	2.6	6.0	9.8	15.0	21.8	29.5	40.1	58.0
Offshore circalittoral sand	42.53	62034.5	3.0	7.7	12.3	17.2	22.9	30.7	41.0	56.0	75.2
Offshore circalittoral mud	24.24	41641.7	4.1	9.4	15.2	21.7	30.1	38.8	49.3	61.6	76.5
Circalittoral coarse sediment	6.92	10233.2	0.4	3.6	6.2	14.0	21.0	28.3	39.8	52.4	66.3
Offshore circalittoral coarse sediment	3.52	11434.1	1.3	4.0	8.2	13.1	18.9	25.9	35.2	46.4	61.5
Infralittoral sand	3.37	21594.1	2.5	10.5	16.1	31.2	38.7	49.6	59.3	69.0	81.9
Circalittoral mud	2.88	7904.5	4.7	8.8	14.1	18.6	24.3	30.5	38.7	48.5	69.8
Circalittoral mixed sediment	2.48	3269.2	0.2	1.1	3.2	6.8	13.3	22.5	33.4	49.5	68.7
Unknown	0.85	3610.8	3.7	5.9	23.8	27.1	30.3	48.2	66.5	75.8	91.1
Infralittoral mud	0.6	877.7	0.0	0.0	2.5	12.0	28.4	36.3	53.5	66.2	87.3
Offshore circalittoral mixed sediment	0.42	825	2.1	5.7	12.5	17.3	20.7	33.2	48.5	63.5	72.6
Infralittoral coarse sediment	0.11	682.9	1.7	20.4	53.9	57.1	67.8	78.3	82.4	88.7	90.4
Infralittoral mixed sediment	0.06	19	0.0	0.8	1.1	1.7	1.7	6.2	6.2	34.0	54.8
Offshore circalittoral rock and biogenic reef	0.04	7.6	0.0	0.0	0.0	<0.1	0.1	3.0	5.1	6.0	24.0
Circalittoral rock and biogenic reef	0.04	6.6	0.0	0.0	0.0	<0.1	0.3	0.5	0.6	0.6	51.5

Gear modifications

Figure 8: Habitat 1

Figure 8. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Southern North Sea subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 9: Habitat 2

Figure 9. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Southern North Sea subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 10: Habitat 3

Figure 10. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Southern North Sea subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 11: Habitat 4

Figure 11. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Southern North Sea subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Channel

Summary

Table 1

Table 1. Values of pressure and impact indicators for 2017‒2022 for three depth strata in the Channel subdivision. Values of I‒1, I‒2, I‒3, I‒4, I‒6a, I‒6b, I‒7a and I‒7b are annual means and I‒5 is evaluated over the six years. Descriptions of the pressure and impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Indicators	0 to 200 m	200 to 400 m	400 to 800 m
I‒1: Average fishing intensity	6.06	NP	NP
I‒2: Proportion of area fished, evaluated at c-square scale (%)	99.70	NP	NP
I‒3: Proportion of area fished (%)	78.30	NP	NP
I‒4: Smallest proportion of area with 90% of fishing intensity, evaluated at c-square scale (%)	46.30	NP	NP
I‒5: Proportion of area persistently unfished, evaluated at c-square scale (%)	0.30	NP	NP
I‒6a: Average PD impact	24.30	NP	NP
I‒6b: Average PD-sens impact	40.30	NP	NP
I‒7a: Proportion of area with PD impact < 0.2, evaluated at c-square scale (%)	53.60	NP	NP
I‒7b: Proportion of area with PD-sens impact < 0.2, evaluated at c-square scale (%)	43.60	NP	NP

Figure 1

Figure 1. Geographic distribution of fishing intensity (swept area ratio), seabed sensitivity (community longevity), total landings value, and total landings weight from mobile bottom-contacting gear (MBCG) in the Channel subdivision. The maps of swept area ratio, landings value, and landings weight show annual means evaluated at the c-square scale.

Table 2

Table 2. Contribution of small-scale fisheries (vessels < 12 m overall length) to total fishing effort (kW × fishing days) in the Channel subdivision. The table shows the total fishing effort (kW × fishing days) by FAO region over the assessment period, and the mean contribution (%) and observed range in contribution (%) of small-scale MBCG fisheries’.

FAO region code	FAO region name	Total fishing effort (kW × Fishing days)	Mean contribution SSF (%)	Observed range SSF contribution (%) [min - max]
27.4.c	Southern North Sea	19239402	0.0	[0 - 0]
27.7.d	Western English Channel	12365350	17.3	[16 - 18]
27.7.e	Eastern English Channel	8267271	32.8	[31 - 35]

Fishing intensity

Table 3

Table 3. Extent (in km² and %) of broad habitat types in the Channel subdivision, and mean annual estimates of MBCG fishing intensity, landings weight, and landings value. In addition, estimates of the average annual proportion of the fished extent, the smallest proportion of the habitat extent affected by 90% of the fishing effort, and the proportion of extent persistently unfished are provided.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Relative habitat extent (%)	Landings (×1000 tonnes)	Value (×106 euro)	Swept area (×1000 km2)	Average fishing intensity (I‒1)	Average annual extent fished (%)	Smallest proportion of extent with 90% of fishing effort (%)	Percentage extent persistently unfished (%)
Offshore circalittoral coarse sediment	15.51	61.1	31.91	86.86	87.75	5.66	78.2	51.1	0.0
Circalittoral coarse sediment	3.68	14.5	8.97	24.11	31.35	8.51	75.9	39.3	0.0
Circalittoral sand	2.26	8.9	5.21	14.41	16.91	7.47	91.5	57.5	0.0
Offshore circalittoral sand	1.30	5.1	5.20	14.89	11.89	9.15	98.3	80.7	0.0
Infralittoral sand	0.92	3.6	2.07	5.23	3.11	3.39	76.2	60.9	0.1
Infralittoral coarse sediment	0.71	2.8	3.18	6.95	1.81	2.54	79.9	73.0	0.0
Offshore circalittoral rock and biogenic reef	0.22	0.9	0.31	0.88	0.53	2.43	45.2	32.9	0.0
Infralittoral mud	0.19	0.7	0.43	1.20	0.66	3.54	86.5	65.2	0.0
Circalittoral mud	0.16	0.6	0.49	1.60	2.18	13.22	98.2	80.3	0.0
Infralittoral rock and biogenic reef	0.16	0.6	0.27	0.73	0.26	1.65	48.0	41.1	0.0
Circalittoral rock and biogenic reef	0.13	0.5	0.16	0.45	0.15	1.19	48.8	50.4	0.0
Offshore circalittoral mixed sediment	0.10	0.4	0.02	0.05	0.08	0.77	12.9	4.9	0.0
Offshore circalittoral mud	0.05	0.2	0.23	0.69	0.74	15.23	99.1	78.8	0.0
Infralittoral mixed sediment	0.01	0.0	0.05	0.13	0.01	1.67	93.2	68.5	0.0
Circalittoral mixed sediment	0.00	0.0	0.00	0.00	0.00	0.66	53.1	86.4	0.0
Unknown	0.00	0.0	0.00	0.00	0.00	1.56	75.4	59.2	0.0

Figure 2

Figure 2. Temporal variation of the pressure indicators I‒1, I‒3 and I‒4 in the Channel subdivision. Descriptions of the pressure indicators are provided in the ‘Essential Information’ Table E1 in this document.

Fishing by métier

Table 4

Table 4. Landings weight and value by métier and their relationship with swept area in the Channel subdivision.

	OT_DMF	SSC_DMF	SDN_DMF	OT_MI	DRB_MOL	OT_SPF	TBB_DMF	OT_CRU	TBB_MOL
Area swept (×1000 km2)	51.78	46.03	22.49	21.30	9.20	3.67	2.94	0.61	0.03
Landings (×1000 tonnes)	7.48	3.09	1.61	8.14	34.30	1.24	1.94	0.09	0.59
Value (×106 euro)	20.14	7.74	4.92	21.35	92.42	2.44	7.72	0.71	0.74
Landings / Area swept (kg/km2)	144.53	67.18	71.64	381.93	3729.73	338.55	658.91	150.81	20525.84
Value / Area swept (euro/km2)	388.95	168.11	218.67	1002.44	10049.68	666.19	2624.98	1169.18	25674.36

Core fishing grounds

Figure 3

Figure 3. Spatial stability of core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Channel subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included. The numbers between brackets show the proportion of fished extent compared to the overall assessed area extent.

Figure 4

Figure 4. Spatial distribution of the stability of the core MBCG fishing grounds, presented as the number of years a c-square is identified as a core fishing ground (smallest area yielding 90% of the landings value) per métier for the Channel subdivision. Only métiers that were active within > 50 unique c-squares during the assessment period are included.

Impact

Figure 5

Figure 5. The spatial distribution of MBCG fisheries impact in the Channel subdivision, as assessed with the PD indicator (I‒6a) and PD-sens indicator (I‒6b), shown as annual means for the assessment period, evaluated at the c-square scale. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Figure 6

Figure 6. Temporal variation in values of the PD indicator (I‒6a), PD-sens indicator (I‒6b), proportion of the extent with PD impact < 0.2 (I‒7a) and proportion of extent with PD-sens impact < 0.2 (I‒7b), shown for the overall area and for the four most extensive broad habitat types separately in the Channel subdivision. Descriptions of the impact indicators are provided in the ‘Essential Information’ Table E1 in this document.

Table 5

Table 5. Métier-specific landings weight and value per unit PD or PD-sens impact in the Channel subdivision.

	OT_DMF	SSC_DMF	SDN_DMF	OT_MI	DRB_MOL	OT_SPF	TBB_DMF	OT_CRU	TBB_MOL
Landings (tonnes)/PD impact	72.2	64.0	98.9	71.3	265.7	71.3	54.6	7.5	740.4
Value (×1000 euro)/PD impact	194.2	160.1	301.7	187.1	715.8	140.4	217.4	58.5	926.2
Landings (tonnes)/PD-sens impact	47.0	35.5	63.0	44.3	161.7	67.4	34.6	6.4	701.6
Value (×1000 euro)/PD-sens impact	126.4	88.8	192.2	116.2	435.8	132.6	137.8	49.9	877.6

Figure 7

Figure 7. Métier-related impacts, reported as annual means of the PD indicator (I‒6a, top) and PD-sens indicator (I‒6b, bottom), on the four most extensive broad habitat types in the Channel subdivision.

Scenarios

Footprint reduction

Table 6: Effort

Table 6. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Channel subdivision, on swept area (presented as % of total swept area within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total area swept (×1000 km2	10%	20%	30%	40%	50%	60%	70%	80%	90%
total	25.4	100	0.5	1.9	4.0	7.9	12.8	19.7	30.0	44.7	65.2
Offshore circalittoral coarse sediment	15.51	87.75	0.1	0.5	1.9	5.3	10.8	18.0	28.1	42.0	63.0
Circalittoral coarse sediment	3.68	31.35	<0.1	0.5	1.4	3.5	6.1	9.9	22.0	39.9	63.3
Circalittoral sand	2.26	16.91	1.4	3.6	5.8	9.3	14.4	21.6	29.9	47.6	69.5
Offshore circalittoral sand	1.3	11.89	2.9	11.5	19.0	26.7	33.9	41.8	50.3	59.5	72.4
Infralittoral sand	0.92	3.11	0.4	0.9	5.6	13.1	20.0	32.9	46.2	60.8	73.2
Infralittoral coarse sediment	0.71	1.81	0.7	6.0	13.3	19.2	23.3	30.7	44.3	57.3	75.4
Offshore circalittoral rock and biogenic reef	0.22	0.53	0.7	1.3	1.7	3.1	4.0	7.1	10.5	17.2	26.9
Infralittoral mud	0.19	0.66	2.0	4.3	8.1	11.9	18.9	32.3	45.8	68.1	83.4
Circalittoral mud	0.16	2.18	3.6	12.0	17.8	32.8	38.4	54.2	64.6	75.6	87.3
Infralittoral rock and biogenic reef	0.16	0.26	<0.1	0.1	0.4	1.6	2.8	12.3	23.2	28.2	51.6
Circalittoral rock and biogenic reef	0.13	0.15	0.1	1.2	4.4	7.0	9.6	19.9	31.6	49.6	68.4
Offshore circalittoral mixed sediment	0.1	0.08	0.9	1.2	2.4	3.9	4.8	6.7	7.7	8.9	10.6
Offshore circalittoral mud	0.05	0.74	3.5	11.6	28.2	45.4	45.4	58.4	75.3	100.0	100.0
Infralittoral mixed sediment	0.01	0.01	3.6	9.6	18.8	43.1	69.4	69.4	100.0	100.0	100.0
Circalittoral mixed sediment	0	0	11.6	38.5	38.5	38.5	38.5	38.5	38.5	100.0	100.0
Unknown	0	0	8.4	8.4	8.4	15.2	21.9	66.0	66.0	100.0	100.0

Table 7: Landings weight

Table 7. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Channel subdivision, on landings weight (presented as % of total landings weight within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings weight (×1000 kg)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	25.4	57101.2	1.1	3.2	6.1	10.9	17.6	26.5	41.5	58.2	74.2
Offshore circalittoral coarse sediment	15.51	31900.5	0.1	0.3	1.3	5.2	11.7	20.6	36.0	52.9	69.3
Circalittoral coarse sediment	3.68	8673.3	0.2	1.3	4.2	6.9	11.9	18.9	40.3	58.1	77.5
Circalittoral sand	2.26	4792.6	4.1	7.3	9.6	14.5	20.4	29.0	39.1	63.0	81.8
Offshore circalittoral sand	1.3	5025.3	4.9	16.8	27.5	35.4	43.7	52.8	59.5	71.2	81.9
Infralittoral sand	0.92	1749.6	1.3	3.5	9.9	20.6	29.4	41.8	52.6	70.0	83.1
Infralittoral coarse sediment	0.71	3127.5	1.0	5.7	11.3	19.7	31.1	41.4	61.4	73.6	85.2
Offshore circalittoral rock and biogenic reef	0.22	300.2	0.6	1.0	1.1	2.0	2.5	4.8	6.9	13.4	26.1
Infralittoral mud	0.19	405.3	4.5	10.7	27.0	40.9	53.0	72.4	80.1	90.0	93.5
Circalittoral mud	0.16	435.7	7.0	23.6	29.5	45.1	51.3	64.9	71.1	77.7	88.9
Infralittoral rock and biogenic reef	0.16	241.6	1.1	1.2	2.1	4.2	8.4	23.0	32.1	38.4	69.7
Circalittoral rock and biogenic reef	0.13	153.5	0.1	1.3	5.4	6.7	9.2	19.0	30.4	42.1	58.4
Offshore circalittoral mixed sediment	0.1	16.8	0.7	0.9	1.9	3.0	3.6	5.0	5.9	8.4	9.8
Offshore circalittoral mud	0.05	229.1	4.2	14.6	27.5	45.3	45.3	55.6	76.4	100.0	100.0
Infralittoral mixed sediment	0.01	49.3	3.9	11.4	18.4	30.1	60.5	60.5	100.0	100.0	100.0
Circalittoral mixed sediment	0	0.7	10.9	57.0	57.0	57.0	57.0	57.0	57.0	100.0	100.0
Unknown	0	0	37.1	37.1	37.1	50.9	75.3	82.8	82.8	100.0	100.0

Table 8: Landings value

Table 8. The effects of stepwise exclusion of all MBCG fisheries from a specified proportion of a MSFD broad habitat type within the Channel subdivision, on landings value (presented as % of total landings value within that habitat type). The stepwise exclusion is conducted in 10% increments, and within each successive increment from 10% to 90% the c-squares with the lowest recorded rank MBCG swept area are excluded. Note that the top row shows the total estimate for all habitats combined.

MSFD broad habitat type	Extent of habitat (×1000 km2)	Total landings value (×1000 euro)	10%	20%	30%	40%	50%	60%	70%	80%	90%
Total	25.4	154273.2	1.1	3.2	6.1	10.7	17.1	25.9	41.0	57.0	73.3
Offshore circalittoral coarse sediment	15.51	86841.3	0.1	0.3	1.3	5.1	11.1	19.7	35.0	52.0	69.1
Circalittoral coarse sediment	3.68	23286.4	0.1	1.2	4.0	6.7	11.6	19.0	41.8	56.5	74.6
Circalittoral sand	2.26	13245.9	4.1	6.9	9.1	13.9	19.7	28.9	38.9	59.6	79.2
Offshore circalittoral sand	1.3	14409.1	4.7	16.6	27.3	34.9	43.3	51.5	57.6	70.2	82.1
Infralittoral sand	0.92	4291.2	1.4	3.5	10.4	20.8	29.8	44.5	57.3	72.9	81.1
Infralittoral coarse sediment	0.71	6831.1	1.2	6.6	11.7	20.0	30.3	42.2	61.5	74.6	86.0
Offshore circalittoral rock and biogenic reef	0.22	861.7	0.5	0.9	1.1	1.9	2.3	4.3	6.3	12.1	25.0
Infralittoral mud	0.19	1106.9	4.3	9.8	22.1	35.5	44.9	65.1	74.0	86.0	92.0
Circalittoral mud	0.16	1443.3	6.3	22.0	28.0	43.2	50.5	64.6	72.2	79.4	90.4
Infralittoral rock and biogenic reef	0.16	658.3	1.2	1.2	2.1	4.0	7.9	20.8	30.1	36.5	69.6
Circalittoral rock and biogenic reef	0.13	424.5	0.1	1.3	4.9	6.2	8.6	16.9	27.8	39.0	53.8
Offshore circalittoral mixed sediment	0.1	45.2	0.9	1.1	2.3	4.1	4.8	6.0	7.3	9.0	10.4
Offshore circalittoral mud	0.05	693.7	4.3	14.7	28.5	45.7	45.7	55.3	79.0	100.0	100.0
Infralittoral mixed sediment	0.01	132.8	3.9	11.0	17.5	29.2	59.4	59.4	100.0	100.0	100.0
Circalittoral mixed sediment	0	1.7	10.7	58.0	58.0	58.0	58.0	58.0	58.0	100.0	100.0
Unknown	0	0.1	28.2	28.2	28.2	38.2	56.0	70.3	70.3	100.0	100.0

Gear modifications

Figure 8: Habitat 1

Figure 8. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Channel subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 9: Habitat 2

Figure 9. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Channel subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 10: Habitat 3

Figure 10. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Channel subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Figure 11: Habitat 4

Figure 11. Effects of gear modifications (5%, 10%, and 20% lower depletion) on the quality-extent relationship for the most abundant MSFD habitat type in the Channel subdivision. Habitat quality is defined as 1 - impact, with impact calculated as PD (I‒6a) or PD-sens (I‒7a). The dotted line represent the extent threshold of 75% for the proportion of a broad habitat type that should not be adversely affected (EU, 2024).

Essential information

Content of this advice product

This interactive document presents information on the distribution, intensity, impact, landings weight, and landings value of mobile bottom-contacting gear (MBCG) fisheries within the Greater North Sea area and the estimated consequences and costs (expressed as loss of landings weight and value) of reducing the relative extent of areas fished with MBCG. The information is from an assessment for the Greater North Sea area for the period 2017‒2022. The six-year period was selected to include the latest available vessel monitoring system (VMS) and logbook data rather than to match a specific Marine Strategy Framework Directive (MSFD) assessment period (EU, 2008). The assessment describes fishing intensity and impact with five pressure indicators and four benthic impact indicators (Table E1).

Table E1. Pressure and impact indicators, including the spatial scale and period for which indicators are evaluated. C-square refers to a grid cell of dimensions 0.05° latitude × 0.05° longitude. Examples of the “defined area” referred to in the description would be an area within a specified depth range or an area with the same BHT.

Indicator code	Indicator name	Indicator type	Description	Spatial scale	Period
I‒1	Average fishing intensity	Pressure	Average number of times a defined area is swept by mobile bottom-contacting gears (MBCG). Estimated as the sum of swept area for all vessels using MBCG divided by the total area of the defined area	Absolute extent (km2)	One year
I‒2	Proportion of area fished, at c-square scale	Pressure	The sum of the area of c-squares fished at least once by MBCG in a defined area, divided by the sum of the area of all c squares in the defined area	C-square	One year
I‒3	Proportion of area fished	Pressure	The sum of MBCG swept area in all c-squares in a defined area (where any swept area > c square area is set to c-square area), divided by the sum of the area of all c-squares in the defined area	Absolute extent (km2)	One year
I‒4	Smallest proportion of area with 90% of fishing intensity, at c-square scale	Pressure	The sum of the area of the smallest set of c squares accounting for 90% of the total MBCG swept area in a defined area, divided by the sum of the area of all c-squares in the defined area	C-square	One year
I‒5	Proportion of area persistently unfished, at c-square scale	Pressure	The sum of the area of c-squares not fished with MBCG at any time in the assessment period in a defined area, divided by the sum of the area of all c-squares in the defined area	C-square	Six years (assessment period)
I‒6a	Average PD impact	Impact	The annual mean PD impact (population dynamics method, impact indicator), evaluated for a defined area	C-square	One year
I‒6b	Average PD-sens impact	Impact	The annual mean PD-sens impact (population dynamics method, impact indicator for sensitive species), evaluated for a defined area	C-square	One year
I‒7a	Proportion of area with PD impact < 0.2, at c-square scale	Impact	The sum of the area of c-squares in a defined area with PD < 0.2 divided by the sum of the area of all c-squares in the defined area (values <0.2 define areas where predicted reductions in abundance of benthic fauna are <20%. The threshold of 0.2 is illustrative only)	C-square	One year
I‒7b	Proportion of area with PD-sens impact < 0.2, at c-square scale	Impact	The sum of the area of c-squares in a defined area with PD-sens < 0.2 divided by the sum of the area of all c-squares in the defined area (values <0.2 define areas where predicted reductions in abundance of benthic fauna are <20%. The threshold of 0.2 is illustrative only)	C-square	One year

For each defined assessment area and subdivision, sections of this interactive document provide “summary” information and information on “fishing intensity”, “core fishing grounds”, “fishing by métier”, “impact”, and “scenarios” (Table E2).

Table E2. Information provided in the tabs for each assessment area.

Tab	Description
Summary	Values of pressure indicators I‒1 to I‒5 and impact indicators I‒6a, I‒6b, I‒7a and I‒7b by depth strata (Table 1).
	Maps of swept area ratio, median longevity of benthic fauna, and landings value and weight (Figure 1).
	Estimates of the contribution of small-scale fisheries (MBCG vessels < 12 m overall length) to total fishing effort in kW × days (Table 2).
Fishing intensity	The extent of broad habitat types, and various estimates of MBCG fishing activity for these habitat types; fisheries landings, value, and intensity (Table 3).
	Temporal variation of pressure indicators I‒1, I‒3, and I‒4 (Figure 2).
Fishing by métier	Estimates of swept area, landings weight, and landings value for the active métiers (Table 4).
Core fishing grounds	Spatial stability of core fishing grounds (smallest area responsible for 90% of the landings value) over time (Figure 3).
	Spatial distribution of the stability of core fishing grounds (Figure 4).
Impact	Spatial distribution of MBCG fisheries impact indicator values (I‒6a) and (I‒6b) (Figure 5).
	Temporal variation of impact indicators I‒6a, I‒6b, I‒7a, and I‒7b (Figure 6).
	Landings weight and value per unit impact for the active métiers (Table 5).
	Métier-specific impacts for the four most extensive broad habitat types (Figure 7).
Scenarios	A “Footprint reduction” scenario presenting effects of stepwise exclusion of MBCG fisheries in each broad habitat type, in terms of effort reduction (Table 6), landings value (Table 7), and landings weight (Table 8).
	A “Gear modifications” scenario presenting the effects of gear modifications (assumed reduction in the depletion of benthic faunal biomass after a gear pass) on the quality-extent threshold for the four most extensive habitat types (Figures 8‒11).

Assessment area

Figure E1. Map of the assessment area, showing the water depth class distributions (left), and boundaries of the relevant (MSFD) divisions and FAO regions (right).

Limitations of this advice

Data and analytical limitations are described in the “Limitations” section of the main advice text. This text should be consulted before viewing this interactive document.

How is fishing intensity evaluated?

Five pressure indicators were used to describe fishing intensity and distribution resulting from the use of MBCG (Table E1).

These indicators are calculated, for any given area as defined in this document, from estimates of the swept area in each of the c-squares within a defined area of interest. The swept area is calculated as hours fished × average fishing speed × gear width. This requires that VMS location records are linked to logbook data to associate a location and speed with gear code and fishing activity (Data Collection Framework level 4 and 6 respectively). VMS locations are allocated to “fishing” and “not fishing” based on vessel speed and other filters (ICES, 2022). The gear width is estimated based on relationships between average gear widths and average vessel length or engine power (kW; Eigaard et al. 2016; ICES, 2022). The swept-area ratio (SAR) is calculated as the sum of the area swept by a defined set of MBCG in a defined area (usually one c-square) in a defined period (usually one year) divided by the area of the defined area. Therefore, when calculated at the c-square scale, the SAR indicates the theoretical number of times the c-square is swept per year, assuming that the MBCG fishing is evenly distributed over the c-square. For example, a SAR of 2 means that the entire c-square is fished two times over the year, a SAR of 0.5 means that the entire c-square is fished once in two years.

How is benthic impact evaluated?

Four indicators were used to describe benthic impacts. These indicators are generated from the assessment methods PD and PD-sens. PD (population dynamics method) is used to estimate the loss of benthic biomass, relative to carrying capacity, from a defined area if the current MBCG fishing intensity continues indefinitely (Pitcher et al., 2017; ICES, 2018; Hiddink et al., 2019; ICES, 2022). PD-sens (population dynamics method for sensitive fauna) is used to estimate the loss of biomass of sensitive benthic fauna (the 10% most long-lived biomass fraction), relative to carrying capacity, from a defined area if the current MBCG fishing intensity continues indefinitely (ICES, 2024). For this advice, PD and PD-sens are estimated at the c-square scale.

PD and PD-sens are estimated from SAR and parameters for depletion (proportional mortality) per pass of a MBCG and the intrinsic rate of increase of biomass of the benthic community (Pitcher et al. 2017). Estimates of depletion were métier-specific and taken from Rijnsdorp et al (2020). The intrinsic rate of increase is estimated from the predicted local distribution of maximum ages in an unimpacted benthic community (Rijnsdorp et al., 2018). When PD-sens rather than PD is calculated, only the 10% most long-lived biomass fraction of this community is used to estimate the intrinsic rate of increase, to address the component of the benthic biomass most sensitive to MBCG.

How are landings values evaluated?

VMS location records are linked to logbook data to associate a location with gear code and fishing activity (Data Collection Framework level 4 and 6 respectively), and with landings weight and landings value records. VMS location records are classified as “fishing” and “not fishing” based on vessel speed and other filters (ICES, 2022). Landings weight and value are then allocated to the VMS location records classified as fishing, based on the time interval between location records or an equal split among location records by day, by ICES rectangle or by trip. Total landings weight or value by c-square, in a given time-interval, are calculated as the sum of the allocations to each location record in that c-square.

References

Eigaard O. R., Bastardie F., Breen M. l., Dinesen G. E., Laffargue P., Mortensen, J., et al. 2016. Estimating seafloor pressure from trawls and dredges based on gear design and dimensions. ICES Journal of Marine Science 73(1): 27−43 https://doi.org/10.1093/icesjms/fsv099

EU. 2008. Directive 2008/56/EC of the European Parliament and of the Council of 17 June 2008 establishing a framework for community action in the field of marine environmental policy (Marine Strategy Framework Directive) (Text with EEA relevance). Official Journal of the European Union L164, 19−40. http://data.europa.eu/eli/dir/2008/56/oj

Hiddink, J. G., Jennings, S., Sciberras, M., Bolam, S. G., Cambiè, G., McConnaughey, R. A., Mazor, T., et al. 2019 Assessing bottom-trawling impacts based on the longevity of benthic invertebrates. Journal of Applied Ecology, 56: 1075–1083. https://doi.org/10.1111/1365-2664.13278

ICES. 2018. Interim Report of the Working Group on Fisheries Benthic Impact and Trade-offs (WGFBIT), 12–16 November 2018, ICES Headquarters, Copenhagen, Denmark. ICES CM 2018/HAPISG:21. 74 pp.

ICES. 2022. Working Group on Fisheries Benthic Impact and Trade-offs (WGFBIT; outputs from 2021meeting). ICES Scientific Reports. 4:9. 133 pp. http://doi.org/10.17895/ices.pub.10042

Pitcher, C. R., Ellis, N., Jennings, S., Hiddink, J. G., Mazor, T., Kaiser, M. J., Kangas, M. I., et al. 2017. Estimating the sustainability of towed fishing-gear impacts on seabed habitats: a simple quantitative risk assessment method applicable to data-limited fisheries. Methods in Ecology and Evolution. 8: 472–480. https://doi.org/10.1111/2041-210X.12705.

Rijnsdorp, A. D., Bolam, S. G., Garcia, C., Hiddink, J. G., Hintzen, N. T., van Denderen, D. P., and Van Kooten, T. 2018. Estimating sensitivity of seabed habitats to disturbance by bottom trawling based on the longevity of benthic fauna. Ecological Applications, 28: 1302–1312. https://doi.org/10.1002/eap.1731

Rijnsdorp, A. D., Hiddink, J. G., van Denderen, P. D., Hintzen, N. T., Eigaard, O. R., Valanko, S., Bastardie, F., et al. 2020. Different bottom trawl fisheries have a differential impact on the status of the North Sea seafloor habitats. ICES Journal of Marine Science. 77(5): 1772–86. https://doi.org/10.1093/icesjms/fsaa050