Department of Natural Resources
Imagine being a lake sturgeon in northern Lake Michigan and feeling like you're ready to spawn. Something is calling you to the Menominee River (separating Michigan's Upper Peninsula from Wisconsin) so you head that way, anxious to head upstream to create the next generation of fish.
Uh-oh! You can't get very far as five dams prevent your journey - thus thwarting your plans.
The population of lake sturgeon below the very first dam in the Menominee River is estimated at about 3,000 adults - who are subsequently prevented from accessing suitable spawning and thus their future offspring's' rearing habitat.
Bummed out? Don't be as a new solution was put into the effect in the form of the lake sturgeon lift to really get things moving (pun intended)!
Several years ago a partnership was developed between the Michigan Department of Natural Resources, Wisconsin Department of Natural Resources, U.S. Fish and Wildlife Service, River Alliance of Wisconsin, Eagle Creek Renewable Energy, New Hydro LLC and Michigan Hydro Coalition in an effort to build a mechanism to get these mature lake sturgeon around some of the Menominee River's dams.
The Fish Passage Partnership got to work constructing a glorified elevator that is located at the Menominee Dam that was completed in 2015. Fish heading upstream can hitch a ride on the elevator into a facility where they can be sorted and where biological information can be collected. Only lake sturgeon are then transported further upstream - while all other species are sent back downstream - so they (sturgeon) can have access to an additional stretch of suitable spawning and rearing habitat.
"We can now transfer sturgeon above two dams to give them 20 more river miles of habitat for adult lake sturgeon," explained Darren Kramer, a fisheries unit manager based out of Escanaba. "Fish that spawn in that area are giving juvenile lake sturgeon six times the amount of rearing habitat they would have had otherwise - which is really critical to their survival."
This is the fourth year the lake sturgeon lift has been used, with the Michigan DNR serving as the chief operators while it's running in the spring and fall.
"In the beginning we had a lot of trial and error about when was the best time of day to catch lake sturgeon in the lift," said Jennifer Johnson, a fisheries biologist out of Crystal Falls. "We now know nighttime is the best time to catch a sturgeon - so that's the hours we keep when we run our eight-week operating window in the spring [March 15 to May 31] and four additional weeks in the fall."
During the operating windows, staff from the DNR and graduate research students from the University of Wisconsin - Stevens Point travel to the sturgeon lift in the early evening and prepare it for the night's activities. This includes making sure everything is turned on, that the gate is up, reviewing data sheets from evening before, and then beginning the real fun.
"This is one of my favorite parts of my job," shared Johnson. "Every time I push the button waiting for the hopper to come up the excitement is there."
For all fish that come up, their length is taken and material is collected in order to age them. Anything other than lake sturgeon is then sent back downriver via tube, while lake sturgeon have additional work done to prepare them for their next journey.
"For lake sturgeon we check whether it's been previously tagged or if we need to put one in," Johnson explained. "These tags allow us to track each fish over time. We'll then check its health and if it meets the length requirements for spawning-size fish - 50 inches for females and 45 inches for males. After that it will go into a holding tank until the end of the night and we can send it upstream."
An additional way a sturgeon is checked for spawning readiness is through ultrasound, which allows the staff to see if it has eggs or reproductive cells inside.
To truly gauge the success of this project time is needed to see increased numbers of juvenile lake sturgeon in the lower portions of the river. This would indicate adult fish are producing in greater numbers upstream and then heading back down to continue living their lives.
"We have a long way to go to figure out how effective this effort has been - not only in the overall goal of more lake sturgeon, but even in how to best operate the sturgeon lift," said Kramer.
The partnership's goal is to pass 90 fish per year - with the bulk of them (60) getting passed in the spring. From spring 2015 through fall 2017, 259 lake sturgeon have been captured with 135 passed upstream - headed on the ride of their lives.