If the sea lamprey population never reproduced, it would eventually go extinct. Reproduction is essential for the survival of any species. In order to be a predator, the sea lamprey attaches itself to other fish and feeds on their body fluids. Adult sea lampreys, which are 12-24 inches long, feed entirely on other fish. They are already predators. They are parasitic in nature and have no jaws, but possess a skeleton made of cartilage. In their native ocean, they don't typically kill their hosts, but in the Great Lakes, where no co-evolutionary link exists, they act as predators and can kill up to 40 pounds of fish each over their 12-18 month feeding period. The Great Lakes Fishery Commission is working on several methods to control sea lamprey populations, including the use of a pesticide called TFM and the release of sterile male lampreys. [2][3]
References:
[1] High predation of native sea lamprey during spawning ...
[2] Great Lakes Fishery Commission - Sea Lamprey
[3] Sea Lamprey
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