Tag: glft

Virus Killing Great Lakes Giants

  • Fishing guide Rich Clarke of Clayton, NY, is famous for muskie hunts. He's worried so many adult muskies are falling victim to VHS. (Photo courtesy of Rich Clarke)

Fall is when avid anglers flock to the Great Lakes for one of the most
challenging freshwater catches: the muskellunge, or muskie. Some call it
“the fish of 10,000 casts.” This year’s muskie season is clouded by bad news
of a new fish disease and invasive species crowding muskie habitat. David
Sommerstein reports scientists are watching this top-of-the-food-chain
species carefully:

Transcript

Fall is when avid anglers flock to the Great Lakes for one of the most
challenging freshwater catches: the muskellunge, or muskie. Some call it
“the fish of 10,000 casts.” This year’s muskie season is clouded by bad news
of a new fish disease and invasive species crowding muskie habitat. David
Sommerstein reports scientists are watching this top-of-the-food-chain
species carefully:




It’s a cool afternoon as fishing guide Rich Clarke fillets the day’s catch:


“Went out, caught some northerns, a few bass, some jack perch. Had a
pretty good morning.”


Clarke’s specialty is hunting for muskies, 60 pound fish with a lot of fight:


“I mean, the rod screams, they yank, yank, and yank. It doesn’t come all that
often, but when it comes, it’s one of the most exciting things you’ll see when
you fish in fresh water.”


Clarke worries that magical hit might become even more rare. Since 2005,
several hundred of those prized muskies were found belly-up dead, victims
of viral hemorrhagic septicimia, or VHS.


(Sound of hose)


Clarke washes down his fillet table. He mutters VHS is just another non-
native organism threatening the muskie. There are already more than 180
invasive species in the Great Lakes-St. Lawrence River system:


“Everything from the goby to the , y’know, and weed species and all
sorts of stuff, spiny water fleas, you name it, all sorts of stuff that are not native to this
waterway that we have to deal with, and it changes the whole ecology.”


A new invasive species is found every six to nine months. Scientists can
barely keep up in understanding the impact on the native environment.




In a nearby bay of the St. Lawrence River in northern New York State,
Roger Klindt, John Farrell, and a crew drag a huge net through the water:


“We’ve got two people pulling it slowly through the vegetation just trying
to basically corral fish.”


This is called seining, getting a sample of all the fish that live here. Klindt
and Farrell have been doing this in the same marshy shallows for more than
20 years. And Farrell says what they’ve found this year is disturbing:


“Muskellunge numbers in the index are at their lowest levels on record since
we’ve been collecting data.”


Down from almost 50 in the spring spawning run of 2003 to just 4 this year.
Farrell’s a researcher with the State University of New York Environmental
Science and Forestry. He says this could be the result of VHS killing so
many adult muskies in their reproductive prime.




Yet another invasive species is also troubling, the round goby. It’s an ugly
little fish from Eastern Europe that breeds like crazy. Farrell and Klindt
count minnows flipping and fluttering in the seining net:


“15 black gins, 8 blunt nose, 5 spot tail.”


“I didn’t actually count things, I was just picking gobies.”


Farrell says they’ve found more round gobies in these marshes than ever
before:


“Which is a bit of a surprise to us.”


Now the muskie young have to compete with round gobies for food:


“How these species are going to respond to the presence of gobies is
unknown at this time, but they have high predation rates, they’re very
prolific, becoming extremely abundant, so the food web in this system is
shifting.”


This is what frustrates people who study invasive species. Once researchers
train their focus on one, like the fish disease VHS, another emerges to
confound the equation. Roger Klindt is with New York’s Department of
Environmental Conservation:


“Change happens, y’know, nothing stays the same forever. But when we
have invasive species and exotic species come in, the change is often so
rapid that native species can’t adapt to it.”


That talk makes anglers nervous. Peter Emerson’s been fishing around here
for years. In fact, he participated in a catch and release program that brought
muskie populations back to health in the 1980s:


“There was a real bonanza, til this virus showed up. I’m hopeful they don’t
go extinct.”


Biologists expect adult muskies that survived VHS will develop resistance to
the disease. But they fear the next generation won’t inherit the immunity,
causing more die-offs of one of America’s most prized freshwater fish.


For The Environment Report, I’m David Sommerstein.

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Warming to Change Great Lakes Ecosystem?

Some researchers say global warming will impact fish habitat in the
Great Lakes. Chuck Quirmbach reports:

Transcript

Some researchers say global warming will impact fish habitat in the
Great Lakes. Chuck Quirmbach reports:


Some scientists have projected that more global warming will mean less
rain and snow falling into the Great Lakes and the continuation
of low water levels.


Researcher Brian Shuter is with the Ontario Ministry of Natural
Resources. He says if the projection comes true, there will be
more stress on the millions of Great Lakes fish:


“I mean the space for fish to live in is just gonna shrink and the less
space there is, the less fish there will be.”


Shuter also anticipates higher summertime water temperatures and less
ice cover in the lakes. That’s a change that could lead to more warm
water fish like bass and fewer of the cold water fish like salmon
and trout that people like to eat.


Shuter says the change could also promote the growth of invasive
species that favor warmer water temperatures. So, he encourages tighter
controls on invasives and more water conservation programs.


For the Environment Report, I’m Chuck Quirmbach.

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Fish Detectives

  • The fish detectives (a.k.a. scientists who specialize in fishery genetics) survey the scene. (Photo courtesy of the Lake Erie Center)

On television, the CSI detectives make forensic lab work look glamorous. It’s a cinch for them to track a criminal by the DNA left behind at the scene. In real life, DNA is also a powerful tool for solving environmental crimes and mysteries. Rebecca Williams visits the Fish Detectives:

Transcript

On television, the CSI detectives make forensic lab work look glamorous. It’s a cinch for them to track a criminal by the DNA left behind at the scene. In real life, DNA is also a powerful tool for solving environmental crimes and mysteries. Rebecca Williams visits the Fish Detectives:


(Sound of gulls and reel being cast)


It’s midday, and it’s so hot the gulls are just standing around with their beaks open.


But Joe Al-Sorghali is still trying to get himself a fish dinner:


“Hopefully I can get a good amount of perch today… they’re not that fishy so they’re a really good catch.”


It takes a lot of these little fish to fill up a dinner plate. But that doesn’t stop Al-Sorghali from going after perch and walleye any chance he gets. A lot of people call Lake Erie the Walleye Capital of the World.


Fishing is a really big deal here. So it makes sense that Lake Erie’s also home to the Fish Detectives.


(Dragnet theme music)


The fish detective headquarters is tucked away on the edge of a quiet cove. The investigators at the Lake Erie Center are not wearing trench coats. They’re not even wearing lab coats. This crew of laid-back lab techs and grad students comes to work in jeans and T-shirts.


Carol Stepien heads up the fish detective squad. She says they solve lots of cases of mistaken identity.


Take the Case of the Fried Perch.


Last year the detectives got a call from a TV station in Milwaukee. The news crew was suspicious that the fried local perch on restaurant menus wasn’t really local.


Stepien says she asked the news station to send her some frozen filets.


“So instead they sent their news crew out into restaurants and had their news crew eat the fish and put a little bit of the breaded, cooked fish in a plastic bag and froze those and sent them to me. We were pretty shocked to get those in our laboratory. We didn’t know if we could get DNA from breaded, fried material like that.”


But Stepien says they scraped off the breaded coating… and they actually were able to extract DNA from the little bits of cooked fish.


“And we found that about half of those fish were yellow perch from Europe.”


Stepien says it’s gotten more common for fish brokers to import yellow perch from outside the U.S. because it’s cheaper. She says even though the foreign perch might taste the same when they’re deep-fried… a close look at the DNA of the European yellow perch reveals big differences from Great Lakes yellow perch.


“They probably could be called freshly caught lake perch, but they were certainly frozen and didn’t come from any local lakes, they didn’t come from the Great Lakes. Instead they came from overseas.”


Stepien’s team will tackle any sort of mystery, as long as it involves gills and fins.


Lately they’ve solved cases of home invasion. That is, invasions by exotic species that’ve gotten into the Great Lakes. The scientists can track the invaders by their DNA fingerprints, and find out where they’ve been.


Joshua Brown is a Ph.D student at the lab. He’s been tracking the round goby. It’s a fish native to Europe. Scientists say it caught a ride to the Great Lakes in the ballast tanks of ocean going ships. It’s been crowding out native species.


“We’re going to find somebody to point the finger at, as it were. We’ve found evidence they came from the northern portion of the Black Sea, right around one of the major ports.”


That port is in Ukraine. Even though they’ve found the culprit, Brown says there’s not much governments can do, because everyone’s guilty.


“I don’t think you could really sue a nation for you know, not keeping their species under wraps. If so, we’d be open for a lot of lawsuits too – we export almost as many as we import.”


But Brown says knowing exactly where a foreign species comes from might help keep the door closed to future invaders from that same region.


Whether it’s a case of consumer fish fraud or defending the home turf from invaders, there’s one bottom line for these detectives. They want to find out as much as they can about native fish so they can keep them from going belly up.


For The Environment Report, I’m Rebecca Williams.

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Making Boat Washing Mandatory

  • Sarah and Mike Litch rake the bottom of Little Glen Lake, identifying plants to make sure there are no new foreign invaders. They want to catch problems early before they spread and completely take over this lake. (Photo by Linda Stephan)

Aquatic plants and animals can cling to the bottom of
recreational boats. That’s one way invasive species are spread. A couple of hitchhiking zebra mussels, or a plant
caught in the propeller are enough to alter the ecosystem of an
entire lake. One resort region has passed laws requiring boaters
to wash their boats before putting them into their local lakes.
But some state officials don’t like the new laws, and that
might make it impossible to enforce them. Linda Stephan
reports:

Transcript

Aquatic plants and animals can cling to the bottom of
recreational boats. That’s one way invasive species are spread. A couple of hitchhiking zebra mussels, or a plant
caught in the propeller are enough to alter the ecosystem of an
entire lake. One resort region has passed laws requiring boaters
to wash their boats before putting them into their local lakes.
But some state officials don’t like the new laws, and that
might make it impossible to enforce them. Linda Stephan
reports:


Little Glen Lake is known for unpredictable winds, and clear
blue waters… at times the lake is turquoise. It sits against
glacial dunes that lead to the eastern coast of Lake Michigan.
Sarah Litch retired here with her husband Mike:


“It was kind of a toss-up between New England and here. Miss
the mountains, but we love the water here. Although there are
so many water issues now. I don’t know.”


Those water issues include foreign invasive plants that could
take over Little Glen Lake:


On a pontoon boat, the Litch’s zig zag across the lake, raking up
aquatic plants at the bottom. If there are any invaders, they
want to find them early.


One of the bad guys they’re looking for is Eurasian water
milfoil. That’s a long, thin plant with feather-like green leaves.
Another invader is Hydrilla. You’ve probably seen it in
aquariums. It’s taken over lakes from California to Indiana, and
on to Maine. Both plants grow very quickly, they choke out native
fish habitat, and form a green carpet on the lake surface:


“And then it can be all – you’re trying to boat in all this tangle
of aquatic plants, or swim. So it just ruins a lake.”


These invaders have likely spread from lake to lake across the
US hitchhiking on boats pulled out of one lake, and headed for
another.


Some states such as Maine and Minnesota now require boaters
to make sure crafts and trailers are free of aquatic nuisances
before they drive down the road with them, possibly
endangering other lakes. And in those states, officials inspect
boats, too.


But other states, such as Pennsylvania and Michigan, have NOT
taken those steps, and Michigan borders four of the five Great
Lakes.


Since the state hasn’t passed laws to prevent boats from moving
invasive species from one lake to another, some local officials
have.


Sarah Litch designed a local law that requires boats to be washed
before going into local inland lakes, and it easily passed in two
adjoining communities. So around here, it’s a 500 dollar fine if
you don’t wash your boat.


Homeowners provide a free wash station at the main point of
entry to Little Glen Lake, a state-owned boat launch, but a few
boaters had refused the voluntary local inspections. That
frustrated Sarah Litch enough to fight for new local laws:


“Just to give people that are working at the boat wash a little more
backup when they have a refusal. So that they can inform the
individual and take their license if they refuse.”


But the local governments might end up in a power struggle
with the state agency that controls the boat launch, the
Michigan Department of Natural Resources. The state
agency doesn’t like this new local law.


Jason Fleming – who’s with the agency – says the homeowners’
boat wash has been successfully running on state property for a
decade, but only because the state allows it with special
permission:


“When we established that with the association, it was based on
a voluntary basis. So we’d have to review the terms and the
language of that agreement.”


In other words, if workers at the wash station start reporting
boaters to the local sheriff for refusing their services. Fleming
says the state might kick them off the state-owned boat launch
property. He says a voluntary approach is enough.


State officials don’t believe the local law applies to the state-
owned boat launch.


Chris Bzdok is an environmental lawyer. He says state courts have repeatedly ruled that local
governments can make laws like this one… and they can enforce them:


“The localities have a right to protect these resources – whether
they’re being accessed through a road end, through a private
marina, or through a state facility. The larger question is why
the DNR has a problem with it. What would be any good-faith,
genuine, substantive reason for opposing that?”


Scanning the lake from the boat launch, Sarah Litch talks of
what to do when – not if – the next invading plant or aquatic
animal arrives.


She says the best way to protect the lakes is to enforce the local
law, to make sure boats don’t bring in new invaders.


For the Environment Report, I’m Linda Stephan.

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