Grand Haven anglers volunteer to track catches of stocked and wild salmon
Last year saw declines in catch rates for Chinook salmon and decreased salmon stocking in response to low baitfish numbers. Anglers in Grand Haven recorded catches to help biologists understand how changes might impact fishing.
March 25, 2014 - Author: Dan O'Keefe, Michigan State University Extension
The Lake Michigan salmon fishery began with the stocking of coho and Chinook salmon in the late 1960s. Since that time, the lake and its fishy residents have gone through several dramatic changes. One significant change is that salmon—Chinook salmon in particular—are now reproducing naturally in clear, cold northern Michigan streams.
For much of the year, Lake Michigan’s stocked and wild-spawned salmon mingle in open water where they chase alewife and feed heavily to put on weight before maturing. At some point, though, they begin to mature and seek out the location they were stocked at or the river where they were born.
The return of mature “kings” to river mouths and harbors is an annual event that many anglers schedule vacation time around to take advantage of excellent fishing. In recent years, though, it has seemed to some anglers that certain rivers are not attracting the number of salmon that they used to. Anglers in Grand Haven, Mich. remember years when fishing between the pierheads for returning salmon was fantastic for several weeks every year, while recent years might only produce one or two good days for this type of fishing.
Looking at catch estimates from non-charter creel surveys conducted by Michigan DNR reveals that anglers in Grand Haven experience ups and downs from year to year and month to month. These creel surveys date back to 1985 and show that an average Grand Haven angler harvests a Chinook salmon every 16 hours. Harvest rates have been above average for eight of the past 10 years, but anglers saw a striking difference between 2012 and 2013. In 2012, anglers harvested a Chinook every 8 hours, with this number dropping to one Chinook every 20 hours in 2013.
One possible reason for this decline is that fewer mature fish could be returning to Grand Haven in late summer. Historically, Grand Haven catch rates are highest in May and peak again in August. In 2013, the same pattern held true. In fact, 68 percent of all Chinook salmon harvested in 2013 by Grand Haven non-charter anglers were taken in August.
Were these large, mature kings staging before heading up the Grand River, or were Grand Haven anglers mostly keying in on immature fish or salmon headed to northern rivers and other ports around the lake? Volunteers with Michigan Sea Grant’s Salmon Ambassadors program helped to provide answers. Last year was the first year for this program, and seven Grand Haven anglers provided length measurements and fin clip data for 736 Chinook salmon caught over the course of the season.
What they found was surprising. While there were a few trophy-sized fish caught, to be sure, smaller Chinooks made up the majority of the August catch. Volunteers reported that 68 percent of August Chinooks were less than 30 inches long. Only 30 percent of Grand Haven salmon caught in August had a fin clip indicating the fish was stocked. Although the largest (Age 3) stocked salmon in Lake Michigan did not all have a clipped fin in 2013, we expected to see an increase in the proportion of clipped fish later in the year as mature salmon returned to their stocking site. Instead, the proportion of clipped fish was the same in June as it was in August.
In September, we did see some evidence that fish stocked in Grand Haven were showing up in the fishery. Volunteers reported 44 percent of September kings had fin clips, and coded wire tags recovered from three fish caught in the Grand River during the Grand Haven Salmon Festival had tag numbers that showed they came from stockings at Grand River net pens maintained by Grand Haven Steelheaders.
The bad news is that catch rates in September were terrible. In a typical year, Grand Haven anglers harvest better than one Chinook every twenty hours. In 2013, it took more than 100 hours for the average Grand Haven angler to harvest a Chinook salmon in September.
Last year was a tough one for many salmon anglers around Lake Michigan. After several years of excellent catch rates, the decline in 2013 was a bit of a shock to anglers, but from a long-term perspective, it is probably a good thing that Chinook numbers are down. With fewer mouths to feed, there is less potential to deplete that baitfish that predators rely on.
The 2012 decision to reduce salmon stocking hinged on this, but any changes that anglers saw in 2013 had little or nothing to do with the latest stocking reduction. After all, the stocking cuts were not implemented until 2013 and these fish were too small to interest anglers last year. Lake Michigan is a dynamic system, and many anglers are watching closely to see what the future will hold.
If you are already measuring your catches and recording your success as many anglers do, consider sharing your data with other anglers and scientists who are tracking our changing fishery. The Salmon Ambassadors program is now open to Lake Michigan anglers in Michigan, Wisconsin, Illinois, and Indiana waters, as well as Lake Huron anglers in Michigan. Contact Dan O’Keefe with Michigan Sea Grant and Michigan State University Extension for details on how to participate.