Term
| Describe a walrus habitat. |
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Definition
| Most walruses live where air temperatures range from 5-41*F. Walruses are generally found in continental shelf waters no more than 262 ft. deep where there is an abundance of benthic invertebrates in the sediment. They prefer a habitat with a gravely bottom. |
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Term
| Why do walruses haul out? |
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Definition
| Walruses haul out to rest, molt, give birth and nurse their young. |
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Term
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Definition
| Benthic means bottom dwelling. |
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Term
| Are walruses the largest species of pinniped? |
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Definition
| No, walruses are not the largest pinniped. Northern and Southern Elephant Seals can be larger. Male Walruses can weigh up to about 3700 lbs. Females can weigh up to about 2700 lbs. |
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Term
| Why do walruses appear pale after a sustained period in cold water, but become pink when hauled out in warm weather? |
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Definition
| Walruses appear pale after a sustained period in cold water due to the contraction on tiny blood vessels resulting in a reduction of blood flow to the skin conserving body heat. Hauled-out walruses become pink in warm weather from the dilation of the tiny blood vessels causing circulation to increase shedding excess body heat. |
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Term
| Do both male and female Walruses have tusks? |
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Definition
| Both male and female walruses have tusks. The tusks of the males tend to be longer, straighter and stronger than those of females. |
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Term
| How do walruses use their tusks? |
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Definition
| Walruses use their tusks to establish social dominance, for defense, and like pick axes to help them haul out onto sea ice. |
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Term
| Why isn't a walrus's sense of sight as acute as other pinnipeds? |
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Definition
| Walruses eyes are probably adapted for short-range vision. Because walruses feed on sedentary bottom-dwelling animals, acute vision is not necessary for survival. |
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Term
| How does a walrus use its vibrissae? |
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Definition
| The walrus's 400-700 vibrissae are extremely sensitive organs. They use their vibrissae to locate food. Studies show walruses are able to discriminate the shape and size of an object using their vibrissae. |
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Term
| How does a walrus establish dominance in its herd? |
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Definition
| Dominance in walrus herds is established by tusk length, body size, and aggressiveness. The largest walruses with the longest tusks are the most aggressive and generate threat displays most often. |
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Term
| What is a walrus's preferred food? |
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Definition
| Walruses prefer eating molluscs, mainly bivalves such as clams. |
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Term
| How many clams can a walrus eat in a single feeding? |
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Definition
| Adult walruses may eat as many as 3,000-6,000 clams in a single feeding. |
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Term
| Why do walruses have the ability to squirt water? |
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Definition
| Walruses may take in mouthfuls of water and squirt powerful jets at the sea floor, excavating burrowing invertebrates such as clams. |
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Term
| How does global climate change affect walruses? |
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Definition
Walruses rely on sea ice as a place to rest between feeding bouts on the shallow sea beds and as a safe place for mothers to rest and care for calves.
When sea ice is further from food resources, walrus mothers have a hard time finding enough food to sustain themselves and their calves.
Mothers and calves must rest on rocky shores, sometimes with thousands of other walruses. If the walruses are startled, this can lead to increased calf mortality from walruses stampeding to the water. |
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