Workshop on scoping of physical pressure layers causing loss of benthic habitats D6C1– methods to operational data products (WKBEDLOSS)

The workshop on scoping of physical pressure layers causing loss of benthic habitats D6C1– methods to operational data products (WKBEDLOSS) is part of a stepwise process to delivering advice on sea-floor integrity for the Marine Strategy Framework Directive (MSFD). In collaboration with its strategic partners, the high level objectives undertaken by ICES within the project were: 1) to identify benthic physical disturbance pressure layers available within ICES and the European and wider marine community across the four EU (MSFD) regions – including the mapping of pertinent data flows and the establishment of criteria needed to ensure the practical use of the data in assessing benthic impact – in the workshop WKBEDPRES1 (ICES HQ 24–26 October 2018); 2) to identify physical pressure layers causing loss of benthic habitats across the four EU regions, including mapping of data flow and establish guidance to ensure the practical use of the data in assessing benthic impact - in the workshop WKBEDLOSS (ICES HQ 11–13 March 2019); 3) to collate physical pressure layer data causing loss or disturbance (October 2018–Aug 2019), using identified sources and targeted data calls; and 4) to evaluate and operationally test the application of compiled physical pressure layer data causing loss or disturbance (WKBEDPRES2, 30 September–2 October 2019).

WKBEDLOSS focused on objective 2, the requirement of MSFD GES Commission Decision (EU) 2017/848 criterion D6C1 to assess the spatial extent and distribution of physical pressure layers causing loss of benthic habitats, within each ecoregion and subdivision. Where information on activities  was missing,  or  where  the  data collected was not suitable  for  this task, data require-ments  were highlighted  by  workshop  participants.  The process necessitated input from many sources, bringing together research science, marine spatial planning, management experts and indicator developers, all components required for the delivery of MSFD. The resultant collated information needs to be appropriate for the assessment of benthic habitats (D1) and seafloor integrity (D6C3-C5) as set out in the Commission Decision.

WKBEDLOSS defined physical loss as any human-induced permanent alteration of the physical habitat from which recovery is impossible without further intervention.
Alteration of the physical habitat refers to a change in the EUNIS level 2 habitat type. Loss can be given as extent in square kilometres, or percentage loss per EUNIS level 2 habitat. Human interventions facilitating recovery (e.g. removal of man-made structures from the seabed, restoring the original substrate by depositing materials or re-introducing species in the case of loss of biogenic habitat) refer to actions allowing the physical habitat to return to its original EUNIS level 2 habitat type.

WKBEDLOSS distinguished between three types of physical loss: sealed physical loss, un-sealed physical loss and the loss of biogenic habitat. Sealed loss, in general, arises where structures or substrates have been introduced which in and of themselves change the physical habitat. Un-sealed loss results from changes in physical habitat due to alterations in physical habitat resulting from an activity or activities and from the indirect effects of placement of man-made structures. This distinction is necessary as data flows recording physical loss differ according to these types.
WKBEDLOSS identified and listed the anthropogenic activities (physical pressure layers) causing physical loss by region. Activities were grouped into those resulting in sealed loss (introduction of structures or substrates) and those potentially resulting in unsealed loss.