Animal research - harbor seal
The harbor seal (phoca vitulina) is a large semi-aquatic mammal that inhabits much of the northern oceanic coast.The seal can grow to be 5 to 6 feet long, and can weigh over 280 pounds. Although the harbor seal spends most of its time in the sea propelling itself with it's back flippers and steering with the front ones, it will sometimes haul out onto beaches or floating ice to rest. It does not have the same grace on land as in the water, and moves by flopping around and inching forward like a caterpillar.
The harbor seal is a carnivore and eats many fish and small sea life including the following:
The harbor seal is a carnivore and eats many fish and small sea life including the following:
- Anchovy
- Sea Bass
- Herring
- Mackerel
- Cod
- Whiting
- Flatfish
- Shrimp
- Crab
- Mollusks
- Squid
Adaptation / Population and other facts
The harbor seal has many adaptations that allow it to live in frigid water and dive to deep depths to search for food. Seals have a thick insulating layer of fat called blubber that acts as insulation against the cold.
Also, harbor seals are able to slow their heartrate which allows them to stay down on dives for more that 20 minutes. To further increase their diving capabilities they have reduced peripheral circulation which allows them to dive to depths of up to 1640 feet. When they dive this deep they experience pressures nearing 750 psi, which would crush a human.
Also, harbor seals are able to slow their heartrate which allows them to stay down on dives for more that 20 minutes. To further increase their diving capabilities they have reduced peripheral circulation which allows them to dive to depths of up to 1640 feet. When they dive this deep they experience pressures nearing 750 psi, which would crush a human.
Scientists in the park have been closely monitoring the seal population since the 1970s, and have noticed a 75% drop in the seal population since 1992. Scientists are still straining to figure out why this has happened but nobody knows for sure yet. Even though the population has dropped, harbor seals are still the most numerous marine animal in the park and if you are anywhere near the water you are bound to see at least one, if not more. Seals are curious animals, and will often follow kayaks in the water. Unfortunately, because they have no real defensive adaptations and a high fat content, harbor seals are a nice snack for killer whales passing through.