Ringed seal post-moulting movement tactics and habitat selection

Area of Science:

• Ecology
• Animal Behavior
• Arctic Biology

Background:

• Intra-specific variation in movement tactics is known, but its link to small-scale habitat selection is understudied.
• Ringed seals (Phoca hispida) display different movement strategies during the non-breeding, post-moulting period.

Purpose of the Study:

• To investigate if ringed seals adjust small-scale habitat selection based on their large-scale movement tactics.
• To identify distinct movement patterns and associated habitat use in ringed seals.

Main Methods:

• Utilized first-passage times (FPT) to analyze large-scale movement patterns.
• Employed Cox proportional hazards models to link FPTs with habitat attributes for quantifying habitat selection.

Main Results:

• Identified two tactics: offshore movement (40-80% ice coverage) and coastal movement (near glacier fronts).
• Offshore habitat selection was driven by sea ice concentration and season, with seals leaving areas in autumn.
• Inshore habitat use depended on distance to glacier fronts and season, with decreased departure risk as winter approached.

Conclusions:

• Ringed seals demonstrate flexibility by employing distinct large-scale movement tactics and adjusting small-scale habitat selection accordingly.
• This spatial ecology flexibility supports population viability in the high Arctic.
• Both movement tactics lead seals to productive areas with necessary ice platforms for resting.