DNR, partners rescue 27 isolated lake sturgeon in Ontonagon River channel

Earlier this month, the Michigan Department of Natural Resources, along with the Keweenaw Bay Indian Community (KBIC) and Upper Peninsula Power Company (UPPCO), conducted three rescue missions to save a total of 27 lake sturgeon from low-water conditions in the Ontonagon River channel (Ontonagon County). The rescue efforts were spurred by a report of three sturgeon stranded in isolated pools in the channel.

On Aug. 23, hikers on the North Country Trail crossed the West Branch Ontonagon River downstream of Victoria Dam. During this crossing, they observed three lake sturgeon in pools in the channel. The hikers reported this observation to the DNR’s Report All Poaching hotline, and the information was forwarded to local fisheries staff.

At this time of year, there is no or low flow in the part of the channel where the sturgeon were discovered. Victoria Dam, operated by UPPCO, is a hydroelectric dam generating power for the region. In accordance with its Federal Energy Regulatory Commission license, flow is diverted from the river to generate hydroelectric power; then it rejoins the West Branch Ontonagon River downstream, leaving much of the river channel between that point and the dam dry or partly dry for parts of the year.

DNR fisheries technicians Kyle Urban and Jack Cole were able to respond to the location, and they found two sturgeon in an isolated pool. They then relocated the fish downstream to where the river reaches full flow, nearly a mile over land in rugged conditions.

Further rescue efforts

DNR staff decided to return to the site with the assistance of KBIC and UPPCO to search more intensively for the third sturgeon that had been observed. They found a large number of live sturgeon in a pool clouded with sediment. Ten additional fish were moved downstream to safety; however, not all fish could be rescued given their location and the equipment on hand. UPPCO released water from the dam into the channel within permit allowances, in hopes of improving conditions in the channel pools for the remaining sturgeon while further rescue efforts could be planned.

Additional DNR staff, along with KBIC and UPPCO personnel, returned to the site for the third mission, and with more people and additional survey equipment, they captured and moved another 15 sturgeon to safety and confirmed that none were left in the dewatered stream channel. Despite the difficulty, this rescue effort was vital for the recovering lake sturgeon population in the Ontonagon system. This situation also provided an opportunity for biologists to gather additional data from these sturgeon they might not have encountered otherwise.

Restoration efforts for lake sturgeon, listed as a threatened species in Michigan since 1994, are ongoing throughout the state; sturgeon have been stocked in the Ontonagon River since 1998. It is likely that none of the sturgeon captured exceed 28 years of age, and the largest fish recovered was 55 inches long. Since sturgeon are long-lived and still recovering in this system, a loss of 27 fish would have been extremely detrimental to that population.

To prevent sturgeon becoming stranded in this part of the river in the future, the DNR is reviewing historical flow and temperature data for this area, as well as considering enhanced surveys with KBIC and UPPCO to identify and relocate fish and aquatic species stranded by low flow conditions.

“Projects like hydroelectric dams have environmental impacts,” said Dave Caroffino, DNR Lake Superior basin coordinator. “We have to work collaboratively with partners like KBIC and UPPCO, as well as the public, to prevent and mitigate negative effects.”

How the public can help

In addition to partnering with tribal governments, utilities and other organizations, public engagement is crucial to protect Michigan’s species and natural resources.

“We can’t be everywhere at once,” said Cory Kovacs, DNR Lake Superior unit manager. “When people report what they’re seeing — like those observant hikers did in this situation — that gives us the opportunity to investigate and address any issues, potentially saving members of a threatened species.”

If you see something unusual, like fish somewhere they shouldn’t be or an unknown fish species you haven’t encountered before, don’t hesitate to report it. You can report observations at Michigan.gov/EyesInTheField or by reaching out directly to your local fisheries biologist. For cases like this, where a threatened species appears to be in immediate danger, you can report it to the DNR’s Report All Poaching hotline at 800-292-7800.

Accompanying photos are available below for download. Caption information follows.

• Two sturgeon: Two lake sturgeon found in an isolated pool in the West Branch Ontonagon River (Ontonagon County).
• Sturgeon transported: DNR staff transported sturgeon to suitable habitat quickly using hiking bags while the sturgeons’ gills remained immersed in fresh water.
• Sturgeon rescued: Lake sturgeon were rescued from a cloudy pool disconnected from the main channel of the West Branch Ontonagon River (Ontonagon County).
• Relocated sturgeon: Twenty-seven lake sturgeon in total were relocated to the main channel of the West Branch Ontonagon River (Ontonagon County).