Wildlife
Alaska Blackfish (Dallis pectoralis):
The Alaska blackfish is distributed throughout eastern Siberia and most of western Alaska. Alaska blackfish inhabit lowland weed-choked ponds, lakes, and sloughs of the Togiak National Wildlife Refuge.
 Alaska blackfish have an elongated body shape with a flattened round snout. Cryptic in color, they can vary from dark green to brown with irregular bands on the sides. Alaska blackfish rarely exceed 8 inches in length, although specimens have been collected up to 12.8 inches in length in Alaska.
Alaska blackfish feed on a variety of prey items including zooplankton, insects, and small fish. Larger fish are know to be opportunistically cannibalistic. The Alaska blackfish is prey for many predators, such as northern pike, other Alaska blackfish, birds, and man.
The life history of Alaska blackfish is not well studied, but it is thought that they spawn in spring and summer throughout southwest Alaska. Adults spawn in the quiet streams and ponds, scattering fertilized eggs on the vegetation. The eggs hatch in about two weeks and young probably get nutrients from their yolk sac for a couple of weeks. Growth can be rapid during the first year depending on food availability and water temperature. Little is known about the migratory behavior of Alaska blackfish, but it is assumed that short movements occur between spawning and feeding areas.
Alaska blackfish are known for their ability to withstand the harsh conditions found in the shallow ponds and lakes of Alaska. Tales are told of the Alaska blackfish's amazing ability to survive freezing; however, total freezing will result in death. They can withstand partial freezing of some body parts, including the head. Alaska blackfish can also endure water devoid of oxygen at 0oC for up to 24 hours. Its tolerance to low oxygen, ability to withstand near-freezing conditions, and varied diet allow the Alaska blackfish to outcompete other fish in many areas.
For more information:
Morrow, James E. 1980. The freshwater fishes of Alaska. Alaska Northwest Publishing Company. Anchorage Alaska.
Or, visit the Alaska Department of Fish and Game's wildlife notebook pages.
Last updated: July 24, 2008
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