Alewife (Alosa pseudoharengus). The fish is not common in Lakes Superior or Erie. (Image courtesy of Wisconsin SeaGrant)
This past year, the size of salmon in some Great Lakes
is getting smaller because their main food source is dying off in some
areas of the lakes. The Great Lakes Radio Consortium’s Lester Graham
This past year, the size of salmon in some Great Lakes is getting smaller because
their main food
source is dying off in some areas of the lakes. The Great Lakes Radio Consortium’s
In the 1960’s, fish and game officials introduced Pacific salmon such as chinook,
steelhead to control the invasive species alewife. That’s a small fish that moved
in from the
Atlantic. The salmon are popular fishing. But since the alewives are not native…
especially susceptible to quick weather changes. And fisheries managers suspect
with zebra mussels for food also affects alewives. Recently, alewife populations
have crashed in
some places. Jim Dexter is with the Michigan Department of Natural Resources…
“The primary reason that there are not alewives in Lake Huron and you get
fluctuations in Lake
Michigan is related more to the climate. You know, now, zebra mussels are tied into
that, into the
equation at some point but not probably to the affect that the climate is having on
So, without as many alewives, salmon don’t have as much to eat… and they’re smaller
Fisheries managers say the effect is probably temporary.
For the Great Lakes Radio Consortium, this is Lester Graham.
Anglers in Lake Superior are looking forward to the return of the coaster brook trout. The native trout was fished nearly to extinction in the early 1900s. New efforts to help the remaining populations rebound are attracting the interest of fisheries managers around the Great Lakes. The Great Lakes Radio Consortium’s Stephanie Hemphill has the story:
Anglers in Lake Superior are looking forward to the return of the coaster brook trout. The native trout was fished nearly to extinction in the early 1900s. New efforts to help the remaining populations rebound are attracting the interest of fisheries managers around the Great Lakes. The Great Lakes Radio Consortium’s Stephanie Hemphill reports:
The French River tumbles into Lake Superior about 15 miles from Duluth. It’s a popular fishing spot, and people are catching rainbow trout. Rainbows are not native to Lake Superior. The Minnesota Department of Natural Resources stocks them from the fish hatchery across the road.
People used to catch coaster brook trout here, but
there aren’t many of the fish around anymore.
“I haven’t seen one of those in years.”
“There aren’t any coaster brook trout. You’re dreaming.”
“‘You very seldom get them, but when you do they’re nice.’ Hemphill: ‘Why are they nice?’ ‘They’re so nice and clean, the colors are so beautiful.’ Hemphill: ‘Are they good eating?’ ‘Oh-h-h, there isn’t any better.'”
For a freshwater fish, coasters are colorful. Their sides are sprinkled with bright red dots. Their fins are edged with a bright white line. When they spawn, their bellies turn iridescent orange.
They hatch in rivers, and then swim downstream to grow up in the lake. They return to the river to spawn.
There used to be lots of coasters around Lake Superior, and in northern Lake Michigan and Lake Huron. They were a popular sport fish. In the 1850s, people came from all over to catch them. By the early 1900s coasters had practically disappeared.
Don Schreiner is the Department of Natural Resources fisheries supervisor in this part of Minnesota. He says coasters are fairly easy to catch. And that’s why they almost disappeared.
“There were no roads up here, people came in by boat, they came in by train. There’s accounts of people standing on the shore and on the riverbank and catching hundreds of brook trout.”
After the fishermen, lumberjacks came. They cut down the big trees that shaded the streams. They floated timber down the rivers, eroding the banks. Now these rivers are much more susceptible to flooding and sedimentation. The coaster brook trout need a rocky bottom, not a mud bottom, to spawn.
Then the state began stocking other fish here, so anglers would have something to catch. Pacific salmon, European brown trout. They compete with the few native brook trout that still survive in Lake Superior streams.
Some people want to try to restore the native brook trout. But others like to catch the big salmon, and the feisty rainbows. Don Schreiner says the DNR has to balance those competing demands.
“I think everybody cares about coaster brook trout as long as it doesn’t cost them anything personally. If I have to give up my favorite species in favor of a coaster brook trout, I might not be willing to do that. That’s the sort of thing we see.”
Angling restrictions imposed in the last few years have helped the trout. Schreiner says it’s possible they’ll bounce back, if people leave them alone, but improving the habitat is also key. That could take 50 years.
Some groups are trying to push things along a little faster.
The Red Cliff Tribal Fish Hatchery near Bayfield Wisconsin specializes in rearing coaster brook trout. Every year a million eggs are hatched here.
“Inside this building is where we keep our adult brood stock fish.”
Greg Fischer is the hatchery manager. He says they raise some fish for a year and a half before releasing them. Workers mark these fish to keep track of them in the wild.
“We have fin clipping parties where for several days we fin-clip each one of the fish, and when we’re stocking anywhere from 50 to 80,000 of these larger fish a year, that’s a lot of marking”
Some coasters from the hatchery might find a home at Whittlesey Creek near Ashland, Wisconsin. The U.S. Fish and Wildlife Service is turning Whittlesey Creek into a refuge for coaster brook trout.
Biologist Lee Newman says it’s a promising spot for spawning. Springs seep up through the gravel bottom. That provides the eggs with a constant flow of oxygen. Newman wants to plant eggs and very young fry directly over the springs. That’s what they did on the Grand Portage Chippewa reservation in Minnesota. And Newman says it worked there.
“We’ve captured pairs of adults that were radio tagged and captured on their spawning beds, and two years later catch the exact same pair on the exact same spawning beds, indicating that they are returning precisely to their home locations.”
Newman says when the fish are very young they can imprint on the chemistry of the stream, and find their way back years later.
Biologists still have a lot of questions about how to help the coaster brook trout. But right now, at least, its future looks a little brighter. For the Great Lakes Radio Consortium, I’m Stephanie Hemphill.