It's something to see every fall in Traverse City, and folks certainly show up to catch the action! But this year, an awful lot of people missed the show at the Boardman River fish weir. They were left wondering why such a short run on Chinook salmon this year.

The answer is the subject of this Fact Finder.

DNR fishery biologist supervisor Todd Kalish oversees the operations at the weir. For the past 23 falls, salmon have been harvested by collecting the fish as they make their way upstream. Kalish explains "We typically install the grates at the Boardman Weir the day after Labor Day and pull the grates the second to last week in October. This year we didn't have as large of a run, so we didn't have a need to leave the grates in as long. "

Fewer fish made their way this year to the Boardman weir this year than in years past. That's why, to the disappointment of many folks who made their yearly trip to see the fish, the fish and grates were gone early. According to Kalish, in a typical year about 5500 fish are harvested, but there is a wide range year to year. In the 23 years the DNR has been harvesting Chinook in Traverse City, the lowest count was 1993 with just under 2300 fish. On the other extreme was 2006 when 13,437 fish returned. The DNR says 2636 Chinook Salmon were harvested this fall.

So why the low number of fish this year? According to Kalish "Chinook salmon typically don't run into streams and rivers unless the conditions are just right so they like to run into streams when we get heavy rains or a cold rain that will typically push them into the weirs. This year during the harvest season of late September through October we didn't have a lot of heavy rains during that period."

So fewer fish were pushed upstream due to the lack of rain, but, that's only half the story. There are also fewer fish out in the big waters to be pushed. According to Kalish "we in 2006 cut the Chinook Salmon stocking numbers, so that will directly effect how many fish come back to the Boardman River in addition to the natural factors."

3 years ago, the DNR planted fewer salmon fingerlings in Lake Michigan after witnessing the Salmon numbers crash in Lake Huron. Huron's problem was partly due to invasive species like mussels which lead to fewer alewives. That's key because salmon eat the alewives. The breakdowns in the food chain lead to a struggling salmon population in Lake Huron. The DNR saw the alewives' number starting to dwindle in Lake Michigan and thus planted fewer salmon in response. The effect today says Kalish is that "we are seeing less fish but they are healthier so we're trying to correct the predator prey imbalance we are starting to see the effects."

As for this year's near record low return, the DNR says, since they can explain why it is so low, it may not be a major concern. Kalish explains "that is an acceptable number, the amount of fish that we bet back varies every year and so if we get continued returns of 2000, or 1000, five years in a row, then that is a reason for concern. One year of a relatively low return we are not significantly concerned about."

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