Monitoring Climate Related Changes in the Availability of Ringed Seal Pupping Habitat in Coastal Labrador

No abstracts are to be cited without prior reference to the author.

Relatively little is known about the adaptive capacity of ringed seals (Phoca hispida) to climate change in many parts of their range. However, because the species requires certain sea ice and snow conditions to successfully overwinter and rear a pup, ringed seals are thought to be sensitive to climatic variability that alters these required habitat characteristics. The pups are born in a protective snow cave (lair) constructed by the female near a well-drifted pressure ridge or ice hummock on landfast ice or relatively stable pack-ice. Adequate snow cover and/or appropriate ice roughness have been correlated with increased survival of ringed seal pups in the High Arctic and in Hudson Bay. The objective of this study was to map and quantify the available habitat for breeding ringed seals using RADARSAT imagery of ice conditions during February and March and data collected by on-ice teams of hunters from the communities of Nain, Hopedale and Rigolet, Labrador. Ice and snow condition data from 2001-2006 at the Nain study area illustrated how expansive intrusions of highly deformed rough ice (2004), extensive sheets of smooth ice (2006), inadequate snow cover (2001 and 2002), an abrupt and early spring melt (2003), and spring storm events (2005, 2006) impacted the availability of suitable pupping habitat. Although, the occurrence and degree of ice deformation was the key determinant of quality habitat, persistent snow accumulation on the ice and the maintenance of a stable ice platform despite severe, unseasonable spring storms (i.e. high seas and rain) appeared to be critical.