Breath-hold capacities and circadian dive rhythmicity shape optimal foraging strategies in a polar marine mammal, the Weddell seal (Leptonychotes weddellii).

ABSTRACT: Air-breathing vertebrates must balance their response to diel shifts in prey accessibility with physiological thresholds and the need to surface after each dive. Weddell seal (Leptonychotes weddellii) dive behaviors were tracked across the year under rapidly-changing light regimes in the Ross Sea, Antarctica ( ~ 75-77°S). This provides a 'natural experiment' with free-living seals experiencing 24-hrs of light (Polar Day), light/dark cycling, and continuous darkness (Polar Night). The Weddell seal's temporal niche switches from nocturnal diving in the summer to diurnality for the remainder of the year. Rhythmicity in dive efforts (depth, duration, post-dive surface recuperation, bottom time, and exceeding physiologic thresholds) is stronger and more closely circadian during times of the yea

SUBMITTER: Shero MR 

PROVIDER: S-EPMC11522681 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature