Lake Michigan salmon anglers did well during the 2011 fishing season. The Chinook salmon catch was up despite the season’s slow beginning. The fish were larger, and anglers had a blast.

In fact, anglers boated 203,000 king salmon on Lake Michigan last year, up from 188,000 the year before. And though the catch rate dropped slightly — from 11 Chinook per 100 hours of fishing in 2010 to 10.2 fish per 100 hours in 2011 — state officials still give the season a big nod.

“That catch rate is still pretty good,” said Dave Clapp, the chief of the Michigan Department of Natural Resources Charlevoix Fisheries Station. “The long-term average is around seven fish per 100 hours, though the peak has been as high as 14 or 15 fish.

“Overall, the total harvest was up, and some of that is due to increased effort. More people went out because they saw bigger fish.”

If all is well, you might ask why fish managers now want to reduce the number of salmon being stocked or reduce stocking for a combination of Chinooks and other species like coho, steelhead and lake trout.

It’s a good question. Lake Michigan is stocked annually with 2.5 million hatchery-raised Chinook fingerlings. But the Michigan DNR and other states are considering cutting that by 30 to 50 percent.

The DNR sponsored a workshop in Benton Harbor Saturday to explain the situation to anglers and to get their feedback. Other Lake Michigan states are doing the same. Each wants anglers to participate in the outcome.

“The prey biomass in Lake Michigan is at record lows right now despite a strong 2010 year-class of alewives that resulted in bigger fish last year,” said Jay Wesley the Michigan DNR’s Lake Michigan basin coordinator. “We’re still seeing really low numbers of alewives, smelt and bloater chubs. There is not much out there, and the predator prey balance is off.”

Which is another way of saying that trouble could be looming. Without enough food to eat, future salmon could be smaller, less numerous or just disappear.

“We just came off a really good year in Lake Michigan, but if you go back and look at 2003 on Lake Huron, which had the largest prey population in its history, the fishery collapsed in 2004,” said Denny Grinold, a charter fishing captain out of Grand Haven and the chairman for The Great Lakes Commission committee of advisers.

Grinold was one of three Michigan representatives on the multistate panel that began meeting last year to determine how much risk of collapse anglers could tolerate. Dennis Eade, the director of the Michigan Steelhead and Salmon Fishermen’s Association, and John Robertson, representing Michigan United Conservation Clubs, were the other two Michigan representatives.

“No one wanted more than a 20 percent risk of alewife collapse and, for some, that was too much,” Grinold said.

They also preferred not to see smaller and fewer fish.

Biologists say several things threaten the future of salmon fishing on Lake Michigan. The alewife forage base is limited. Quagga mussels are filtering out the tiny organisms that young alewives need to thrive. The lake has only six alewife year-classes. It typically has nine, and more is better since it lessens the chance of collapse should disease wipe out any one.

Ninety-five percent of the alewives were born in 2010. The big Chinooks are eating them up. No alewives were born in 2011.

“We are getting to the point of losing the older, bigger spawning fish (alewives),” Wesley said.

The good news is in salmon reproduction. DNR studies show that 50 percent of the 1-year-old Chinooks are natural. They spawn in streams and contribute to the fishery. Up to 80 percent of the mature fish also are natural, but Wesley said fish managers are less certain of the number because of difficulty in determining their markings.

“It suggests we may be over-relying on hatchery fish,” Wesley said.

That’s not a bad problem to have, one might think. The Lake Michigan salmon experiment is evolving into a self-sustaining fishery. However, more salmon means any food will disappear more quickly. And Chinook, unlike other species, eat only alewives. Hence, the cut.

Wesley said Lake Michigan states are considering four primary options to reduce Chinook stocking:

Cut by 50 percent and wait five years to make further changes.

Cut by 50 percent and monitor weights closely. If 3-year-old Chinooks weigh less than 15 pounds, more cuts might be warranted; if weights increase, so might stocking.

Cut Chinook stocking by 30 percent and other species, except lake trout, by 10 percent, then monitor and adjust. This allows the lake trout rehabilitation effort to continue.

Cut Chinook stocking by 30 percent and all other species, including lake trout, by 10 percent, then monitor and adjust.

“All four policies have to be agreed upon by all the states,” Wesley said. “We can live with any of the four.”

Can you?

Michigan and other states will be taking comments for 30 days. Anglers and others who are interested in the decision can submit comments online at miseagrant.umich.edu.