WASHINGTON — Sen. Kirsten E. Gillibrand and Rep. Louise M. Slaughter on Friday demanded stronger action from the Obama administration to head off the increasingly likely invasion of the destructive Asian carp into the Great Lakes.

Gillibrand, D-N. Y., urged the federal government to temporarily shut locks in the Chicago area that could allow the invasive fish into the lakes, where scientists fear they would devastate the existing species.

And Slaughter, a Fairport Democrat and co-chairwoman of the Congressional Great Lakes Task Force, joined the group’s other leaders to prepare a letter to President Obama asking the federal government to devise a permanent hydrological barrier to solve the problem.

“We cannot afford to allow Asian carp to enter the Great Lakes,” Slaughter and several other lawmakers from the region said in the letter, which they plan to send to the president next week. “We look forward to working with you to combat this potentially devastating invasion.”

The lawmakers’ actions came two days after an Asian carp was found for the first time beyond the electronic barriers put in place to try to restrain the huge, gluttonous fish.

Commercial fishermen caught the 3-foot-long, 20-pound bighead carp in Lake Calumet on Chicago’s South Side, about six miles from Lake Michigan.

In the wake of the find, Gillibrand renewed her earlier call, first made in December, to close the O’Brien and Chicago locks, which connect Chicago-area waterways to Lake Michigan.

“For the sake of the region’s economy and ecosystem, I urge you to take immediate action to stop the spread of this species into the Great Lakes and consider the possibility of permanent hydrological separation,” Gillibrand said in a letter to the heads of the Environmental Protection Agency, the U. S. Fish and Wildlife Service, the U. S. Coast Guard and the Army Corps of Engineers.

“The potential for long-term irreversible economic damage is too great to risk keeping the locks open and simply continuing the current unsuccessful plan,” she added.

Two types of Asian carp escaped from fish farms during flooding in the South and entered the Mississippi River in the early 1990s. The species have been making their way upstream ever since.

The giant carp can grow up to four feet long and weigh up to 100 pounds. Given that they eat up to 40 percent of their body weight every day, scientists worry that if they enter the lakes, they eventually will crowd out the native species and destroy the region’s $7 billion fishing industry.

Despite the growing threat, industry wants to keep open the man-made waterways connecting the Mississippi River and the lakes, saying the waterways are essential to shipping.

“The Army Corps of Engineers has confirmed that at this time there is no need to close area locks over this discovery,” said Mark Biel, executive director of the Chemical Industry Council of Illinois. “As the government’s own studies have shown, lock closure undermines the resources and regional support necessary to solve this problem, while doing nothing to protect the Great Lakes.”