Net Pen Project

The 2012 Steelheader net pen project at Harbor Beach received another 15,000 yearling steelhead from Fisheries Division in May.  Thumb Chapter Steelheaders have been working with the DNR Fisheries Division on a 3 yr rearing project in which yearlings are released when they reach the smolting stage in their development.

The steelhead arrived on May 8 as parrs and, after two weeks of intensive feeding in the harbor net pens, achieved their brilliant silver sides…an indication that they were ready for their dash for the open waters of Lake Huron. Their survival rate in the pens was rather remarkable, with only 6 lost in the 2-week period.

Each steelhead was marked by a missing adipose fin, clipped at the hatchery to identify a coded wire tag imbedded in its nose. When harvested, the cwt tag can be “read” to identify its net pen heritage at Harbor Beach.

When these net pen fish were released on May 22, another 15,000 cwt marked steelhead were delivered from the hatchery and released directly into the harbor off the Detroit Edison dock. This control group will help evaluate the success of net pen reading for steelhead…an added step that proved to increase the survival rate of Chinook salmon back when they were stocked in southern Lake Huron. Incidentally, the present salmon fishery in southern Lake Huron is virtually 100% wild, with these salmon probably arriving from Georgian Bay.

While this 3-year net pen project for steelhead won’t produce any tangible harvest results for a couple more years, previous steelhead stocking efforts by the Fisheries Division in southern Lake Huron appear to be very successful. Creel survey harvest rates for 2011 broke an all-time record. And the spring fishing tournaments off the Thumb in 2012 have seen excellent 7-9 pound steelhead at the weigh-ins.

Next spring will be the final year in this steelhead net pen project, but the Thumb Steelheader net pens will be available for future fishery research projects.