Southeast tanner crab and golden king crab will both be harvested starting Thursday. But these two species live very different lifestyles.
Tanner crabs, Chionoecetes bairdi, like to live at the mouths of tidewater glaciers. They live in glacial silt that's rich in tubeworms, which they eat. Their habitat is much shallower than goldens - 60 to 70 fathoms (360 to 420 feet). Their life cycle is regular: Eggs always hatch and males always molt in the spring. Mature tanner females stop growing when they reach maturity, unlike king crabs. Biologists estimate they take five years to reach maturity, though they don't know exactly; tanners are harder to tag than some other crabs.
"With tanner, there are predictable locations between years where you'll find a lot of females," said Gretchen Bishop, Alaska Department of Fish and Game biologist. "Fishermen kind of know that those are always going to be female grounds, and they stay off of them."
Golden king crabs, aka brown kings or Lithodes aequispinus, live in the deepest Southeast waters, 100 to 350 fathoms (600 to 2,100 feet). They like rocky edges. Their life cycle isn't synchronized to the seasons or each other, as it is for tanner crabs. That's characteristic of deep-water species, because the climate doesn't change as much down there.
Like all crabs, they eat a variety of food: starfish, barnacles, sea urchins and tubeworms.
Because the best hunting grounds are in deep water, crab boats often are more exposed. Crabbers generally need a bigger boat, a lot more line and heavier pots to harvest goldens.
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