EPA says a new non-native species of zooplankton has been found in the Great Lakes. Scientists suspect it may have come from ship ballast, and are not sure what effects, if any, it will have on ecosystems.

"In 2008, the U.S. government followed Canada's lead and began requiring overseas ships sailing up the St. Lawrence Seaway to flush their ship-steadying ballast tanks with mid-ocean saltwater to prevent new species invasions of the Great Lakes.

The shipping industry has hailed the program as a remarkable success, pointing out that no new invasive species have been discovered in the lakes since that time. That can no longer be said.

The U.S. Environmental Protection Agency said last week a new species has been discovered in the Great Lakes — the first since 2006 — bringing the tally of non-native organisms in the lakes to at least 186."

Dan Egan reports for the Milwaukee Journal Sentinel November 5, 2016. [2]