Quick Northern Fur Seal facts
1. Northern fur seals have extremely dense underfur beneath longer guard hairsNorthern fur seals have extremely dense underfur beneath longer guard hairs.
2. Adult males are several times heavier than females and develop…Adult males are several times heavier than females and develop thick necks and shoulders.
3. During breeding, large males establish territories packed with multiple femalesDuring breeding, large males establish territories packed with multiple females.
4. Many animals return annually to the same island rookeries in Alaska and RussiaMany animals return annually to the same island rookeries in Alaska and Russia.
5. Outside breeding seasonOutside breeding season, females and juveniles spend months continuously at sea.
6. They feed on schooling fish and squidThey feed on schooling fish and squid, often diving repeatedly at night.
7. Long front flippers generate most swimming power and also support movement on landLong front flippers generate most swimming power and also support movement on land.
8. The historic fur trade killed millionsThe historic fur trade killed millions, and population trends remain a conservation concern in parts of the North Pacific.
9. Northern Fur Seal is a marine mammal and breathes air with lungsNorthern Fur Seal is a marine mammal and breathes air with lungs, even though it spends much of its life in the ocean.
10. It is warm-blooded and uses dense furIt is warm-blooded and uses dense fur, body fat or both to reduce heat loss in cold water.
11. Females give birth to live pups and produce rich milk…Females give birth to live pups and produce rich milk that supports rapid early growth.
12. Its limbs are modified into flippers that generate thrustIts limbs are modified into flippers that generate thrust, steering or both during swimming.
13. Northern Fur Seal must haul out onto land or ice…Northern Fur Seal must haul out onto land or ice for important activities such as resting, molting or breeding.
14. Sensitive whiskers detect water movement and can help track prey…Sensitive whiskers detect water movement and can help track prey when visibility is poor.
15. Large oxygen stores in blood and muscle support underwater foraging divesLarge oxygen stores in blood and muscle support underwater foraging dives.
16. Like other pinnipeds, Northern Fur Seal can slow heart rate…Like other pinnipeds, Northern Fur Seal can slow heart rate and redirect blood flow during dives to conserve oxygen.
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Why northern fur seal are fascinating
Northern fur seals are migratory North Pacific pinnipeds with dense coats and dramatic breeding colonies. Looking at these traits together reveals how the animal solves the everyday challenges of feeding, movement, communication, reproduction and survival.
Frequently asked questions
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