May 6, 2015—If invasive bighead carp and silver carp spread into Lake Erie, there would be enough food available for these species of Asian carp to survive, according to a new study by the U.S. Geological Survey.
This information is critical in helping resource managers mitigate effects of an Asian carp invasion. If bighead and silver carp were to populate Lake Erie, they have the potential to damage native fish populations and the Great Lakes economy.
USGS scientists used satellite imagery of Lake Erie showing algae on the surface to determine how much food would be available for Asian carp. Green algae and blue-green algae, specifically floating algal blooms that can be seen on the surface, are a preferred food source for Asian carp. The water temperatures and algal concentrations detected in Lake Erie from 2002-2011 show that the bighead and silver carps could not only live in this environment, but could continue to grow. The full report is available online.
“Remote sensing imagery shows that Lake Erie has huge areas of available food that are often several times more concentrated than necessary for Asian carp growth, particularly in the western basin,” said USGS scientist Karl Anderson.
Food availability and water temperature are the greatest sources of uncertainty for predicting fish growth potential. Water temperature is a big factor in determining how much bighead and silver carps need to eat. Models developed by USGS scientists helped determine how much algae bighead and silver carps need to eat to survive.
For the past 10 years, algal blooms in Lake Erie have been increasing. Remote sensing images showed that the amount of algae doubled, and in some places quadrupled, from 2002-2011. Throughout the lake, algal blooms encompass several hundred to several thousands square kilometers. Specifically, the western part of Lake Erie has algal concentrations that are several times greater than what is needed for bighead or silver carp to survive.