Stripers under microscope Lake Pleasant
Study to find bass' effect on Pleasant
Special for The Republic
Feb. 3, 2005 12:00 AM
A taxidermist's replica of a 29-pound striped bass hangs on the wall above fisheries manager Dan Grim's desk at Pleasant Harbor Marina.
The mount was inspired by a striper found floating on the lake several years ago.
"One of our employees saw it on the surface," Grim said. "It was obviously in distress because it had at least a 2-pound largemouth bass in its mouth, and the head of the largemouth was sticking out of the huge fish's gill cover."
Striped bass, originally a saltwater fish still found today off the West and East coasts, have been making their way into Lake Pleasant through the Central Arizona Project canal. The CAP feeds Pleasant from Lake Havasu on the Colorado River, the site of the first striper plants in the late 1950s and early 1960s.
Today stripers abound up and down the Colorado River. The state of Utah also planted them in Lake Powell in the mid 1970s, and the fish have worked their way down through Lake Mead and into Lake Mohave. The Havasu fish are now found up the river to below Davis Dam, which backs up Mohave.
Some anglers feel the proliferation of striped bass negatively affects the quality and quantity of largemouth bass, a prize game fish. Others enjoy catching the fish, and the Arizona Game and Fish Department is in the second year of a 3 1/2-year study on how the striper influx will affect Lake Pleasant.
"Our goals are to evaluate the striped bass population in the CAP canal system and its contribution to the lake, to determine reproductive success and recruitment of striped bass in the lake and to determine the demands of white bass, striped bass and largemouth bass and their effect on the primary prey source, the threadfin shad," said fisheries research biologist Marianne Meding, who leads the project.
Federal Sport Fish Restoration Funds derived from excise taxes on fishing tackle and related products financed the study.
"We will be using hydroacoustic equipment, similar to the depth and fish finders used by anglers, to document high-density, open-water populations," Meding said. "We also will be implanting sonic telemetry devices in the abdomens of approximately 15 stripers so we can track their migration movements."
In addition, the study calls for dietary samples from white bass, striped bass and largemouth bass to try to calculate demand on the shad.
Striped bass are prolific and require a lot of threadfin shad, a small minnow that serves as their main food source, to survive.
Largemouths also find shad very appealing, but Meding said she believes any decline in largemouth fishing has more to do with the lack of nutrients coming into the lake during the drought.
"With all the runoff this winter, the lake should be full of nutrients," she said.
If stripers are reproducing in the Lake Pleasant system, Meding said, there is no way they can be removed.
"If we have a population, we'll have to deal with it and promote catching them using proper management," she said. "Striped bass are really a very nice fish, and with proper education, we can help anglers catch them. Currently there is no limit, and anglers can catch as many as they want."