Staff inject a PIT tag under a scute on Lake Superior, near Ontonagon, Michigan. - Photo courtesy of Keeweenaw Bay Indian Community

Staff picking the catch on Lake Superior, near Ontonagon, Michigan. - FWS photo

To help restore the ecological integrity and fishery potential of Lake Superior, fishery agencies developed the Lake Sturgeon Rehabilitation Plan for Lake Superior.  Many agencies are collaborating to protect and rehabilitate sturgeon populations per this plan.  One collaborative survey effort started in 2005 was undertaken once again in  2006. 

Lake sturgeon have been absent from the Ontonagon River for nearly 100 years.  In 1998, sturgeon returned to the Ontonagon River via stocking by the Michigan DNR.  Sturgeon have been stocked each year since -- with the exception of 2003 and 2005.  The fish stocked were collected as eggs from the nearby Sturgeon River, also a tributary to Lake Superior.  The number of fish stocked ranged from 2,000 – 6,500 annually.  Prior to release, a microscopic piece of metal (coded wire tag) was injected into snout of each of the five-to-eight inch long sturgeon.

Surveys of the progress of this rehabilitation effort have been limited in scope and conducted primarily in the river.  The Keweenaw Bay Indian Community, Michigan DNR, GLIFWC and U.S. Fish and Wildlife Service collaborated to conduct a pilot survey in 2005 in Lake Superior waters near the mouth of the Ontonagon River.  The agencies are interested in gathering more information to evaluate stocking progress and to describe the status of lake sturgeon in Lake Superior near the Ontonagon River.

To continue on the success of last year’s effort, the Ashland FRO again used the USFWS R/V Chub as the platform for the gill net survey work.  To minimize capture of non-target species, nets were set and lifted at roughly 12 hour intervals.  We were able to get eight 24 hour sets (16 lifts) during the week of October 2-6, 2006 obtaining our target of a deep and shallow set in each of three statistical grids. 

A total of 6,300 feet of net was set.  29 juvenile lake sturgeon ranging from 401 mm to 986 mm were captured.  Coded wire tags were detected in 23 of the 29 fish captured, positively identifying them as stocked fish.  In addition, a thumb-nail size piece of tissue was collected from the fins of all fish.  Fin clips will be genetically analyzed by Michigan State University to determine the parental origin of these fish.  The sturgeon were tagged and released.  If these fish are captured during future Lake Superior survey work, agencies will obtain data on the growth and movement of these fish.