Fish Fry Day: Shad, Like Ships, Use Locks to Get Upstream

Happy Fish Fry Day, when, like any good Wisconsin restaurant, we put fish on the menu. Today’s post is shared with permission from The Nature Conservancy‘s “Cool Green Science” blog. Thanks, TNC! 

An Alabama shad. Photo: © Steve Herrington

New Research Makes A Strong Case for Fish Passage

By Justine E. Hausheer, science writer at the Nature Conservancy
How do you figure out where a fish was born? You shoot a laser beam at its ear bone.
It may sound like a riddle, but this technique is helping Nature Conservancy scientists protect the Alabama shad, which once swarmed up Gulf-coast rivers as far north as Iowa by the millions to spawn. But shad populations plummeted in the last century, as dams blocked their path upriver.
As covered previously on Cool Green Science, Steve Herrington, the director of freshwater conservation for The Nature Conservancy’s Missouri program, devised an ingenious way to help shad in Florida’s Apalachicola River make it beyond the Jim Woodruff Dam.
Using a PVC pipe and a pump to create the sound of running water, Herrington and his partners at the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Service, the National Oceanic and Atmospheric Administration, the Florida Fish and Wildlife Conservation Commission, and the Georgia Department of Natural Resources were able to coax the shad into the lock used to transport boats over the dam.
Called “conservation locking,” this technique successfully transported fish over the dam to spawn upriver, and the shad population increased by more than four fold, to an estimated 120,000 fish as of 2012. A recovering shad population is good news for the region’s sport fisheries, too, as young shad are likely an important source of prey for largemouth bass.
Keep reading at the Nature Conservancy’s “Cool Green Science” blog –>