By Steven Maier
The University of Wisconsin-Milwaukee’s School of Freshwater Sciences is one of the few facilities in the state that is allowed to hold lake sturgeon in captivity.
“We’ve been involved in Great Lakes sturgeon restoration for probably 30 years,” said Eric Leaf, the school’s assistant dean for advancement.
The sturgeon in this 500-gallon tank are 7 months old and the subjects of a nutrition study, the results of which will help researchers design healthier diets for the fish to prepare them for stocking in the wild.
The lake sturgeon, which can grow up to eight feet long and weigh over 800 pounds, are raised and released into the wild with trackers, Leaf said. Many start in Lake Winnebago, located in eastern Wisconsin. From there, they travel around the Great Lakes, their route mapped by researchers studying the fish’s behavior, who sometimes fly planes low along the river systems to pick up their signals.
The lake sturgeon faced extinction in the Great Lakes, Leaf said. But their numbers are looking better in the state of Wisconsin, which boasts the healthiest sturgeon population of the region. Even so, the sturgeon have a ways to go before they can rest easy.
Sturgeon repopulation is difficult because they’re so long-lived–surviving for as many as 100 years. Females reach sexual maturity around 26 years of age, males slightly earlier, meaning many of the fish the university has raised have yet to reproduce.