Lake Ontario alewives help some fish, hurt others and vex officials

The fate of both popular, but non-native, Lake Ontario sport fish and native species depends on alewives.

Alewives sustain popular sport fish, but can hurt populations of native lake trout and Atlantic salmon. Photo: dnr.state.md.us

But swings in the population of this invasive fish that other species like to eat forces a constant fish-stocking balancing act. Two years ago, it seemed the small prey fish was heading for a crash because of too many predators. But officials in New York and Ontario released a report this month that says alewife populations are stable and managers will continue stocking the fish that eat them at the same levels they have been.

Alewives are the primary food for popular and lucrative, but non-native, sport fish – chinook and coho salmon. They eat invasive zooplankton, like fishhook flea and spiny water flea.

But the news isn’t all good. They also eat native zooplankton that sustains native fish. They compete with perch for food.  They eat young lake trout. Their guts have bacteria that cause a vitamin B1 deficiency in some fish that eat them. That can hurt reproduction in lake trout and sometimes kill Atlantic salmon – both native species.

For those managing Lake Ontario fish, the little prey fish are a dilemma.

“Alewife are an incredibly important baitfish for a very lucrative sport fishery that contributes about $144 million a year to the New York state economy,” said Steve LaPan, a Lake Ontario unit leader for the state’s Department of Environmental Conservation.

“But too many alewife hinder the restoration of other species,” LaPan said.

Echo reported in 2010 that Lake Ontario seemed destined for an alewife population crash because of growing chinook salmon populations.

That didn’t happen.

“The population is actually up a little bit from last year,” LaPan said. “We expect the adult population to go up this year too.”

A dearth of alewife would also spur poor growth in chinook salmon, which has not been the case, LaPan said.

The invasive small fish has crashed in Lake Michigan and Lake Huron. That resulted in the populations of fish that rely on them dropping while the numbers of fish with more diverse diets increased. Michigan officials just announced that they would cut their Lake Huron chinook salmon stocking in half this year, mostly because of the alewife crash.

And just because alewife appear strong now in Lake Ontario doesn’t mean that can’t change, LaPan said.

“As we know from (lakes) Michigan and Huron, Great Lakes ecosystems can change rapidly from exotic species,” LaPan said. “They can go off a cliff without much warning.”

With seemingly stable alewife populations, LaPan said officials would maintain the same salmon and trout stocking levels.

And it seems to be working for those who fish for a living.

“Catch rates have been very good the past few years,” said Bob Songin, captain of Reel Excitement Charters based Rochester, N.Y. Songin takes people on Lake Ontario to fish for chinook salmon and brown trout mostly.

Chinook salmon are popular among commercial anglers. They also eat a lot of alewives. Photo: duke.edu

Songin said there would always be people trying to restore the natural fish species like Atlantic salmon and lake trout. He recognized alewife can hurt these species through the vitamin B1 deficiency, but he hasn’t seen it.

“The survival of Atlantic salmon lately has been great,” Songing said. “We’re catching more Atlantics than ever.”

New York officials and charter captains like Songin give volunteers from charter associations young salmon and steelhead to raise in Lake Ontario tributaries. The fish are out of the hatchery sooner and charter captains know the fish will return to those tributaries in the fall to spawn, which helps them catch more.

This clears room for hatcheries to focus on Atlantic salmon and lake trout – native species that officials are trying to restore, while still keeping chinook and coho anglers happy.

“When you increase stocking of a species, that inevitably means something else will be decreased,” LaPan said.

There are groups unhappy with non-native stocking practices. But even those in favor of a native focus understand the ever-changing ecosystem.

“We would love to see restored natural ecosystems,” said Krystyn Tully, vice president of Lake Ontario Waterkeeper, an environmental nonprofit group that advocates for the protection of the lake.

“But we understand the only way to achieve healthy ecosystems is to have people feel a connection to the water and its well-being,” Tully said. “And a lot of times that means people sportfishing for stocked fish.”

LaPan agrees and said the notion of returning Lake Ontario to its natural state is a credulous one.

“There’s an ecological truth left out of this discussion – this isn’t the same lake as it was back then … whenever back then was,” LaPan said. “Even if we stopped stocking the big predators, we still have over 175 invasive species now.

“The lake is highly perturbed and will be for many decades.”

13 thoughts on “Lake Ontario alewives help some fish, hurt others and vex officials

  1. Pingback: Would You Believe There Are Salmon in Scarborough? Highland Creek Salmon Run

  2. Not a bully Tom, just giving you reality. DNR would never say let’s get rid of the walleyes (or the salmon) to save the alewives, even though they’re considering some serious cuts of salmon due to all the naturals.

    Losing a half-million fishermen since ’86 is not due to salmon. Salmon stocking/management began 20 years earlier than that (’66 Michigan, ’68 Wisconsin) and was an immediate boon to Great Lakes businesses, spawning its very own industry with boats, downriggers and other speciality equipment, not to mention all the shore and pier equipment that was tweaked. Thousands of guides and charters took out tens of thousands of new customers. Now, take a look around at any conservation banquet or civic club. You’ll see a lot of gray hair. The younger generation are not joining/doing like we used to. Today they’ve got iPods, iPads, Facebook, Twitter, Wii, XBox, PS3, smart phones and so much more.

    A study released earlier this year estimated that the average American child ages 8 to 18 spends more than 7-1/2 hours plugged in per day. Another study found that 75 percent of teens had a cell phone and, on average, sent or received more than 3,000 texts per month.

    The explosion in digital distractions and disruptions threatens to make today’s children the first American generation to grow up effectively isolated from nature. Childhood obesity has become an epidemic.

    It’s certainly not for loss of access to fisheries. The most basic species that lured my generation a half-century ago, panfish, are still available in good numbers on lakes, ponds, rivers and flowages across the Great Lakes’ states. Same with bass, bullheads, carp and catfish, northern pike and many more. It could even be argued, based on the average winning weights/fish lengths in fishing tournaments, that access to trophy walleyes, smallmouth bass and muskies has never been better.

    Bait shops gone? It’s called competition, and the “bad guys” are big names like Wal-Mart, Gander Mountain, Bass Pro Shops, Cabela’s, Fleet Farm and most recently, online ordering.

    The nearshore declines of perch fishing has as much to do with ultra-clear water filtered by zebras, then quaggas, than alewives. When I was a kid, you could only see bottom off the end of the pier after two or three days of dead-calm winds. Today, you can see bottom a mile off shore in 30 to 40 feet of water, great for divers, not so great for anglers who are now getting almost all their action in low-light, or when the nearshore waters are murky from wave action or run-off.

    The changes to the lakes from the mussels are likely irreversible. They’ve filtered out so much of the bottom of the food chain, clearing the water and slowing the growth of everything from alewives, bloaters and whitefish to perch and other angler favorites.

  3. If people would actually read all the studies we paid for, all that’s happening now was predicted. All that’s about to happen, is also predicted, yet we have to ignore real fish biology,years of aquired knowledge, to save an invasive species. The solution is there as well, but it appears we aren’t really allowed to fix anything, only look like we’re (they’re) doing something.

  4. Tom:

    It is wonderful to hear someone as knowledgeable on the lakes as you. You make great points.

  5. Thanks Jim. Bottom line is we’re all supposed to be fighting invasive species. The Alewives are an invasive species, a very bad one, regardless of whatever value salmon may or may not have, it requires maintaining an invasive species as dominate, to provide food for them. Asian Carp feed like zebra mussels, alewives, and common carp (they found out bighead carp will root in the mud as well) plus can grow too big, for predators (if allowed) a salt water, cold water predator that can only survive with a special diet is useless, as they are now for the invasives currently spreading with relative ease. Yet they keep trying to ram the salmon down our throats, based on license sales (and the loss of) clearly the minority user group. We have to face facts, we merely have to switch to steelhead/browns,to keep the niche big lake fishery, all would benefit, including the lakes, which is the most important thing. Closing the Chicago river is much more complicated, and wont stop the carp anyway.

  6. Yes they school, and they used to trawl for them, but that was stopped when they figured out they could run out, and salmon can’t survive without them. The problem here is, when they come in to spawn it’s right when native fish hatch, and they eat them, plus zooplankton. Documented many times. You can come here and take all the alewives you want, I wont mind.

  7. So in the Great Lakes the alewives are an invasive species problem but here on the East Coast where they are native they are so scarce that the feds are looking at declaring them an endangered species. There must be some way to satisfy both sides. I know that on the coast we are desperate for those alewives. They are critical prey fish for our beloved striped bass and for use as bait in Maine lobster traps.
    Do alewives school in the lakes the way they do in the ocean? Can you trawl for them?

  8. If the MDNR went to the towns around Saginaw Bay, and said we have to get rid of the Walleyes, in order to restore the Alewives,for salmon would they get out alive? Both alewives and salmon require a mostly native predator free environment, to survive. Chinook salmon were planted in the great lakes from 1873 to 1933 trying to establish a self sustaining population, didn’t take. We had not finished wiping out the native fish population yet, it was already occupied. In the pacific northwest they are trying to get rid of thier invasive species threatening the salmon, non-native Walleyes and Perch. 1/2 million people quit fishing in Michigan since 1986, many bait shops gone, this is when they started managing the lake for salmon/alewives. This also is when invasive species exploded. Safe for alewives safe for all invasives, and very safe for Asian carp. I’ve already been threatened, bullies are punks, I don’t care for bullies. Steelhead can be a year round fishery, salmon are not. A diversified fishery also means a diversified and larger customer base to draw from. But not the point, we have an invasive species problem, we have to fight all invasive species or we fight none. The results are going on right now. Salmon guys want me to compromise, the compromise being everyone else and the natural ecosystem has to compromise not them. Like I said, I don’t care for bullies.

  9. Tom, you say that, but ask guides and charter captains what happened when salmon fishing crashed. Ask them if other species are picking up the slack. Talk to owners of gas stations, sport shops, marinas, hotels, bars, restaurants and gift shops and ask them if the loss of salmon has hurt. Sorry to say, but you might feel real fortunate to get out of there alive if you tell them you see no logical reason to be concerned about alewives and salmon.

  10. I’ve read many studies on alewives. In thier native habitat they run 100’s of miles upstream to spawn. Cities fought with each other for putting dams in and blocking them from upriver towns. When Alewives got into the Great Lakes, they changed thier spawning and feeding habits. They were filter feeders, then became predators of larval fish. The entire composition of zooplankton changed in Lake Michigan after thier arival, they prefer larger zooplankton. Tho they may provide food for salmon, (the only fish dependant on them) I can see nothing positve, from a healthy ecosystem angle, and no logical reason to be concerned for thier welfare. The loss of alewives in Huron has resulted in all native fish rebounding, surviving the spawn not seen in 40 years, (Documented). Switching to steelhead (non-native but not dependant on one fish) keeps the big water fishery and allows the restoration of native fish, which have adapted to the new invasive food, currently unlimited. It might be fun to catch a salmon, but it’s not worth sacrificing the entire natural ecosystem for one fish, that has to be spoon fed a special diet.

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