In the area with the largest sea lamprey population, what is being done to reduce this population?

In the area with the largest sea lamprey population, a few things are done to reduce and control this population. Lampricide, Currently, the primary method to control sea lampreys utilizes a lampricide, called TFM, that kills sea lamprey larvae in streams with little or no impact on other fish.   Barriers,Barriers have been constructed to block the upstream migration of spawning sea lampreys; most barriers allow other fish to pass with minimal disruption. Barriers have eliminated lampricide treatment on some streams and reduced the stream distance requiring treatment on others. The Sterile-Male-Release-Technique, The sterile-male-release-technique aims to reduce the success of sea lamprey spawning. Each year male sea lampreys are collected and sterilized. When they are released back into streams the sterile males compete with normal males for spawning females. Lastly trapping, Sea lamprey traps are operated at various locations throughout the Great Lakes, often in association with barriers. Traps are designed to catch lampreys as they travel upstream to spawn. 

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