A New York senator said a full federal study is needed to determine how big a bite Asian carp would take from the regional economy if they invade the Great Lakes.

Democratic Sen. Charles Schumer said he will request a comprehensive study in a letter he plans to send Monday to the Environmental Protection Agency, Coast Guard, Army Corps of Engineers and Fish and Wildlife Service.

Two species of Asian carp are threatening to enter Lake Michigan from Chicago-area waterways.

State officials and scientists say if the carp spread across the lakes, they could threaten the $7 billion fishing industry by starving out competing species.

Schumer says a broader analysis is needed that would consider potential damage to other industries such as tourism and shipping -- and costs to governments from monitoring and control programs.

"No studies have been conducted to assess the true economic impacts of allowing Asian carp to establish a breeding population in the Great Lakes," Schumer said in the letter, which was provided to The Associated Press. "The lack of this crucial information makes it impossible to weigh the options before us and determine the best course of action to fight the spread of Asian carp."

An economic analysis released this month by the Illinois Chamber of Commerce found that closing the shipping locks in Chicago waterways would cost the area economy about $4.7 billion over two decades.

That report envisions a far greater economic ripple than a February study commissioned by the state of Michigan.

Transportation specialist John Taylor of Wayne State University in Detroit and James Roach, a consultant, said Illinois was overstating the economic damage closing the locks could cause. They estimated it would boost the costs of transporting and hauling cargo by about $70 million annually -- a fraction of Chicago's $521 billion economy.

The U.S. Supreme Court twice has rejected Michigan's request to order the locks closed.