Graduate Research Course
Polar Seal Biophysics
From 96-minute Weddell dives to elephant seals reaching 1750 m, from crabeater krill-filter teeth to leopard seal penguin ambush — the physiology of Pinnipedia.
About This Course
Pinnipeds — phocid “true” seals, otariid eared seals, and odobenid walruses — are the most aquatic carnivores short of whales. A Weddell seal holds its breath for 96 minutes and dives under Antarctic ice at 600 m. A southern elephant seal foregoes air for 2 hours and reaches depths approaching the diving research submersibleAlvin. This course treats their diving biochemistry, sensory systems, and the ecology of ice-bound life.
Cross-links: Climate & Biodiversity M9,Polar Bears,Polar Penguins,Cetacean Biophysics.
Nine Modules
M0
Pinniped Evolution
Pinnipedia divergence ~30 Mya, Pinnarctidion & Enaliarctos stem fossils, phocid vs. otariid split, pinniped-ursid sister-clade relationship.
M1
Weddell Seal Diving
Record dive duration 96 min, Kooyman 1966 hour-long dives, aerobic dive limit (ADL), diving reflex bradycardia, under-ice breathing holes.
M2
Elephant Seal Deep Diving
Mirounga depths to 1750 m, continuous dive cycles, neutral buoyancy exploitation, lung collapse, Le Boeuf 1988-2020 tracking data.
M3
Blubber & Thermoregulation
Subcutaneous blubber thermal conductivity 0.15 W/m/K, countercurrent flipper heat exchangers, critical temperature Tc, metabolic compensation.
M4
Arctic Seal Species
Ringed seal Pusa hispida (breathing holes), bearded seal Erignathus barbatus, harp seal Pagophilus (white-coat pup), hooded seal pumping bladder.
M5
Antarctic Seal Species
Weddell, leopard seal Hydrurga (apex predator), crabeater Lobodon (multi-cusp teeth krill filter), Ross seal Ommatophoca, population 30M Antarctic.
M6
Locomotion: Ice vs. Water
Phocid caterpillar crawl vs. otariid forelimb walking, swim kinematics Fish 1996, Reynolds regimes, on-ice thrust generation.
M7
Whisker & Sensory Systems
Vibrissae wake-tracking (Dehnhardt 1998), undulated harbor seal whisker vortex-reduction, underwater vision specializations, amphibious hearing.
M8
Predation & Leopard Seal
Orca predation on pack-ice seals (wave-washing), leopard seal hunting penguins, crabeater krill filter-feeding mechanics, Rogers 2009 acoustics.