Sea lampreys are bad news and the U.S. Environmental Protection Agency has come up with a new way to deal with the invasive species by registering a mating pheromone as a biopesticide.
Called 3kPZS, the sea lamprey mating hormone released by males works like an alluring perfume, attracting females onto nesting sites. However, as a biopesticide, it will be used to lure female sea lampreys into baiting sites where they can be collected before they get the opportunity to breed.
Researchers have been studying how to use pheromones to manipulate sea lamprey's behavior since the 1990s. The mating pheromone 3kPZS has been tested in baiting sites before and the results of those tests paved the way for it to be registered for official use as part of the EPA's sea lamprey control program.
According to Dr. Weiming Li, a Michigan State University professor part of the Great Lakes Commission's Partnership for Ecosystem Research and Management, the field trial carried out to test the effectiveness of 3kPZS showed a boost in trapping efficiency by up to 53 percent. Additionally, baited traps were found to capture twice more sea lampreys compared to traps without baits.
Initial trials prior to the registration used pheromones naturally derived from male sea lampreys but a synthetic version will also be manufactured in partnership with private company Bridge Organics.
The EPA registration applies to both synthesized 3kPZS and a mixture of solvents and the synthesized pheromone used in the field. U.S. Geological Survey director Dr. Suzette Kimball referred to it as a milestone, the culmination of combined efforts to come up with cutting-edge ways to control the sea lamprey population in the Great Lakes.
The Great Lakes area represents a $7-billion fishery industry. Once the biopesticide is registered in both the U.S. and Canada, it will officially become part of the Fisheries and Oceans Canada and U.S. Fish and Wildlife Service's arsenal to control the sea lamprey population. Aside from biopesticides, traps, barriers and lampricides are used.
"U.S. EPA registration of the sea lamprey mating pheromone opens the door for use of the pheromone in the commission's sea lamprey control program, which protects Great Lakes fisheries from destruction caused by invasive sea lampreys," said Dr. Robert Hecky, chair of the Great Lakes Fishery Commission.
A biopesticide refers to any substance that is naturally occurring and can be used for controlling pests. Others registered include disparlure, a pheromone used for detecting and controlling small gypsy moth infestations. 3kPZS is the first vertebrate biopesticide registered.
Photo: U.S. Fish and Wildlife Service - Midwest Region | Flickr