Where’s the bait?
Lake Michigan anglers can now share bait ball images with USGS scientists.
It is no secret. Lake Michigan’s ever-popular salmon fishery is struggling. The salmon stocking program, which began fifty years ago, has scaled back in recent years. Most recently, Chinook salmon stocking was cut by 50 percent in 2013. Managers in state and tribal agencies responsible for making such decisions agreed that Lake Michigan baitfish were simply not capable of feeding so many hungry mouths for much longer.
Most anglers were very supportive of the lakewide stocking reduction (see survey results), but since 2013 Chinook salmon fishing has been on the decline and some anglers are questioning the status of baitfish in the lake.
The same challenge is heard on the docks, in tackle shops, and at fishing club meetings around Michigan. It goes something like this. “If there is no more food left for salmon, then why do I see huge schools of baitfish on my fish finder every time I am out on the water?”
Is it possible that anglers are seeing something different than the biologists who monitor baitfish abundance trends? The short answer is yes. The longer answer is that long-term trawl and hydroacoustic surveys used to monitor baitfish are extremely valuable and should not be dismissed by anglers concerned with the health of the lake. Even so, the long-term surveys used by biologists do have their limitations just as any sampling protocol does. Lake Michigan is immense, and it is not practical to expect scientists to be able to sample fish at all locations all of the time.
That is where anglers might be able to help. Dr. David Warner is interested in finding out just what anglers are seeing on their fish finders. This may help to piece together a better picture of when and where batifish schools (or “bait balls”) are showing up.
Warner is a Research Fisheries Biologist with the U.S. Geological Survey’s Great Lakes Science Center. The USGS has been involved in bottom trawl surveys of Lake Michigan dating back to 1973. Since so much effort has gone into this program for so many years, Warner is very concerned when anglers report seeing trends that seem to be at odds with trawl data showing alewife and total baitfish biomass at all-time lows.
The problem is that angler reports do not mean much unless they are collected carefully over an extended period of time. That is why Warner is interested in enlisting anglers to send in photos of fish finders when they find bait balls, along with the date, time, location, depth, latitude, and longitude.
With this information, Warner and other USGS scientists may be able to detect patterns that reveal when and where baitfish congregate. If the patterns from fish finder data don’t match up with when and where USGS trawls sample, then Warner may be able to explain differences between what anglers see and what the trawls catch.
Learn more at workshop
To learn more about baitfish trends and other angler science projects on Lake Michigan, come to the Southern Lake Michigan Fisheries Workshop, 7 p.m. to 9:30 p.m. April 21, 2016, in South Haven. The workshop is organized by Michigan Sea Grant and Michigan State University Extension, and hosted in cooperation with the South Haven Steelheaders.
Michigan Sea Grant helps to foster economic growth and protect Michigan’s coastal, Great Lakes resources through education, research and outreach. A collaborative effort of the University of Michigan and Michigan State University and its MSU Extension, Michigan Sea Grant is part of the NOAA-National Sea Grant network of 33 university-based programs.