Linking ringed seal foraging behaviour to environmental variability

Area of Science:

• Marine biology
• Animal behavior
• Conservation science

Background:

• Foraging behavior is critical for animal energetics, survival, and reproduction.
• Understanding habitat use and behavioral changes is key to assessing environmental impacts on species.

Purpose of the Study:

• To classify dive types and estimate behavioral states of Saimaa ringed seals (Pusa hispida saimensis).
• To identify environmental and temporal drivers of foraging behavior in this endangered subspecies.

Main Methods:

• Utilized hidden Markov models and telemetry data to classify seal dives.
• Employed generalized additive mixed models to analyze foraging probability and its drivers.

Main Results:

• Identified three (winter) or four (summer) distinct dive types, including foraging dives.
• Found significant seasonal differences in behavior, with more foraging in summer (36%) than winter (21%).
• Foraging probability peaked in July, was higher during daytime, and varied with lake depth seasonally, with females showing sheltered water preference in winter.

Conclusions:

• Saimaa ringed seal foraging is influenced by diel vertical fish movements and availability, with seals optimizing energy acquisition and conservation, especially in winter.
• The observed flexibility in foraging strategies may enhance the subspecies' resilience to climate change.