Originally Published: January 5, 2018 5:45 a.m.
FLAGSTAFF (AP) — The National Park Service is considering measures like electric shocks, fish barriers, genetic techniques and other means to reduce invasive fish species in the Grand Canyon and Glen Canyon areas in northern Arizona.
Some of the park service’s proposed methods to control the rising number of invasive brown trout and green sunfish in the Colorado River have drawn concern from environmental organizations and the Arizona Game and Fish Department, the Arizona Daily Sun reported.
Among the control options, the park service proposed electrofishing — the process of putting an electric current into the water to stun fish, allowing them to be pulled out of the water.
Fishing groups and the state agency have opposed this idea, saying the process would reflect poorly on the fishery and might have negative effects.
Electrofishing at a rate that would make it effective against brown trout would also negatively affect the noninvasive trout populations, said Chris Cantrell, chief of fisheries for the state Game and Fish Department. Cantrell said this technique has a low catch yield and would not be effective in the Colorado River.
The park service also proposed using genetically altered fish — males with YY chromosomes — to eventually crash a population. Any offspring from those fish would be male, which, Cantrell said, would create a gender imbalance and eventually reduce the population.
Some opponents said this method could be counterproductive as it would introduce more of the invasive species into the mix.
The park service is still in the planning phase on how to control the invasive species, said Rob Billerbeck of the National Park Service.
“There is a range of alternatives we are looking at. We are really open at this point and have tried to be very inclusive,” Billerbeck said. “As we hear back from the public and conduct our analysis then we will likely weed through those actions and may weed out some of them. We also might get a few new ideas.”