Answer: They are all univited (and unwanted?) guests in U.S. ecosystems. That, and they're all Asian. But I'm sticking with the invasive species angle.
Ohio officials have long considered the Asian carp a dire threat to Lake Erie’s $10 b illion-a-year tourism and fishing industries. Concerns have grown since 2009, when DNA tests indicated the fish had slipped past a Chicago-area electric barrier meant to keep them out of Lake Michigan.
The carp eat most of the food that native fish rely on. Some specimens can weigh as much as 50 pounds.
“The key is to stop them before they get in, and that’s why these physical barriers are so important,” said David Ullrich, the Great Lakes and St. Lawrence Cities Initiative director. “We need a higher degree of certainty.”...
Ohio government leaders, including Gov. John Kasich, express support for the barriers but are concerned about funding the project.
Kristy Meyer, clean-water director for the Ohio Environmental Council, said the risk justifies the expense.
“One out of every 10 jobs on the lake is supported by tourism,” Meyer said. “That’s all at risk."
Just a quick back-of-the-envelope calculation to see if the risk justifies the expense: The proposed barrier costs $3,000,000,000. My quick calculation is there are roughly 300,000 people employed in Ohio Lake Erie bordering counties who are not employed in Cleveland or Toledo (I'm ruling out urban jobs as they are unlikely to be affected by loss of tourism). If 1 in 10 of those jobs are at risk, and Ohio's portion of the cost of is 50%, then we are talking about $50,000 in expense per job loss prevented ($1,500,000,000/30,000). Worth it? You be the judge.