Like everybody else, I thought that any big news coming out of Washington’s Great Lakes Days this week would be about the Great Lakes restoration budget. And certainly that’s what most of the briefings and conversations are about.
But lost in the budget news are important new developments about (you guessed it) Asian carp. From a brief, low-key presentation to the Great Lakes Commission, we learned that Asian carp are much more likely to reproduce and have much more food to eat in the Great Lakes than scientists previously thought.
That means that if the invasive carp make it to the Great Lakes, they’re likely to spread fast and far and do even more damage than we’d feared.
Here’s what we heard. Dr. Leon Carl, director of the scientists at the Great Lakes/Midwest division of the USGS (that’s the US Geological Service, the science agency charged with doing much of the fisheries research on Asian carp), on Monday told the Commission that scientists had discovered two new problems:
- Asian carp larvae learn to swim vertically at younger ages than scientists had previously assumed. What that means is that the larvae don’t need to be suspended as long in turbulent water to survive and thrive…. which means that shorter river segments or even the coastal areas of the Great Lakes themselves can support Asian carp reproduction. That’s very disturbing news. Until now, scientists thought that Asian carp could only breed in a handful of long tributaries to the lakes, which would limit their ability to spread if they did get into the lakes. Now their capacity to breed and spread looks much greater.
- Asian carp eat Cladophora, a common algae that grows along much of the Great Lakes shoreline. That’s another stunner. Scientists had believed that there wasn’t enough food in much of the Great Lakes to support the voracious carp. Now it turns out that there’s plenty of food along much of the coastline to support the spread of the invasive fish.
After the briefing, Leon told me that these new findings make him deeply concerned. He’s right.
The likely damage from an Asian carp invasion has just skyrocketed, as has the urgency for taking action. So far, we’re lucky that the monster carp haven’t established breeding populations in the canals or Lake Michigan. But we can’t count on being lucky for much longer.
We need the Corps to construct a permanent barrier, and fast.