fishes - The Environment Report

Population Control for Cormorants

Biologists Jim Farquhar and Mike Smith inspect the cormorant nests in the treetops. (Photo by Karen Kelly)
Some black-crowned night heron chicks in a nest. They've returned to Little Murphy Island on the St. Lawrence River after four years of cormorant management. The cormorants often destroy the vegetation the herons nest in. (Photo by Karen Kelly)
fisherman Steve Sharland. He feels the cormorant should be eradicated from the region. (Photo by Karen Kelly)

The pesticide DDT almost wiped
out the double-crested cormorant.
Now, the bird is thriving, and it’s
blamed for devouring fish in lakes,
rivers, and fish farms in many parts
of the country. Karen Kelly reports
on the struggle to share resources
with this unpopular bird:

Transcript

(sound of clanking and birds)

Mike Smith eases a boat into the shallow water just off Little Murphy Island. It’s a tiny patch of sand and trees in the middle of the St. Lawrence River. It straddles the New York border with Canada.

Smith is a wildlife technician with New York’s department of environmental conservation. He specializes in cormorant management. That means he knocks down nests, breaks eggs, and – very occasionally – shoots them.

Before he even jumps off the boat, he starts counting the birds that are poking out of nests in the treetops.

“I see a few. I’m looking at their nests. We tried to have a zero percent successful reproduction rate.”

Smith counts maybe ten nests. They started with 150 or so in the spring.

There are tens of thousands of these birds. They spend their summers in the north. And in the winter, they go south where they raid fish farms.

Biologists estimate each bird eats a pound of fish a day. That can make a dent in the local fish population. The birds also strip trees of their leaves to create nests. And their guano ends up killing the trees’ root systems. That ends up driving out other animals that need vegetation.

Some people feel the birds should be eradicated. One group of anglers was even arrested for killing hundreds of them on Lake Ontario.

There are others, like the group Cormorant Defenders International. They feel they should be protected.

It’s up to biologists like Jim Farquhar of New York’s Department of Environmental Conservation to find the balance between human needs and cormorants.

Farquhar: “We have needs too, as people.”

Karen: “And we’re competing with them.”

Farquhar: “And we’re competing with them in some cases. Hopefully, if we can inject good science, we make good decisions as a result.”

The biologists’ biggest effort has been on Lake Ontario. They’ve been destroying nests there — and killing some adults – for ten years. Farquhar says they’re finally seeing results.

They’ve reduced the cormorant population on the lake by about two-thirds, and the fishing’s improved.

Now, the biologists are trying to have the same success on the St. Lawrence River. But they’ve only seen a 13% decrease in the number of cormorant nests and they’ve been doing it for four years.

Part of the challenge is that most of the birds live on Canadian soil where management is left to the landowner.

Local anglers like Steve Sharland of Ogdensburg, New York, are frustrated with the slow progress.

“They should eliminate them. They’re not a Northern New York bird and what they’re doing to our fisheries is a sin.”

That’s a common misconception. Actually, the cormorant is native to the region but few people have seen them in such large numbers.

Sharland says some people are so frustrated, they’ve been shooting the birds illegally. But Jim Farquhar believes those are isolated incidents.

“Mike just mentioned that we’ve got some black-crowned night herons nesting out here. It’s another species we’re concerned about, and one we’ve been trying to actively protect from the cormorants. So that’s a good sign.”

A good sign. But it’s another species trying to live on this small patch of land. And the biologists’ balancing act has become even more delicate.

For The Environment Report, I’m Karen Kelly

Great Lakes Fish Linked to Diabetes

DDT was banned in 1972, but traces of it are still all over the place - including in Great Lakes fish. (Photo courtesy of Tony Arnold)

Scientists have known for a long time
that a lot of wild-caught fish have
dangerous contaminants. People
who eat fish have to weigh the health
benefits against the risks of consuming
those pollutants. Now, some research
could make that balancing act even
trickier. Gabriel Spitzer has more on
the link between diabetes… and an
infamous old chemical many assumed
was long gone:

Transcript

In the early morning hours, anglers gather on Navy Pier in downtown Chicago.

Ray Penn is practically within casting distance of the city’s skyscrapers.

He dips his line in the waters of Lake Michigan, hoping to pull out something tasty.

“I filet ‘em, and I fry ‘em, yeah. They got a little bit of bones in ‘em, but – oh yeah. Oh, yeah, baby! I felt that!”

It’s looking like a good morning for rock bass.

“See, there’s a bass on the end of this. This is a small bass, now this guy here, he’s edible.”

Penn says he eats fish a couple of times a week, without giving it a second thought.

Down the pier, Patrick Duhan has the same attitude.

“This is the Great Lakes! It’s such a big body of water. It’s almost like the ocean. They throw tons of crap in the ocean, and there’s just too much of it to screw up.”

But, scientists say, people have managed to screw up the Lakes a fair amount.

Epidemiologists have been studying a group of sport fishers, like these guys, and charter boat captains, who eat a lot of Great Lakes fish.

Mary Turyk of the University of Illinois at Chicago measured the contaminants in their blood, and tracked their health over the years.

“We found we had 36 cases of new diabetes. And what we found was that DDE, the metabolite of DDT, was related to diabetes incidence.”

DDT.

That’s the pesticide made famous by Rachel Carson’s book, “Silent Spring.”

The chemical was banned in 1972, but traces of it are still all over the place – including in fish.

And like mercury or PCBs, it concentrates as it moves up the food chain.

So you don’t have to eat much.

“The captains were eating, I think, on average, a meal a week. One meal a week? Yeah. That doesn’t seem outlandish or anything. No, it doesn’t. It doesn’t at all. In fact, recommendations from the FDA for eating fish, based on mercury levels, are two meals per week, for pregnant women.”

So just half that much fish was linked to about a 33% increase in diabetes cases.

Turyk says it’s not clear how DDE or DDT might contribute to diabetes.

It may have to do with effects on hormones or the immune system.

“We really need more basic science to determine mechanisms that might be responsible for this.”

Another unknown is just how dangerous might this be, and when does it start to outweigh the advantages of an otherwise healthy food?

Tamara Duperval is a family doctor at a West Side Chicago clinic.

She says she still tells people to eat more fish.

“In our population, it’s really a wonder and a challenge to try to present fish as an option, when primarily the staple of diet is either chicken or beef.”

That population is mostly low-income and minority.

She says about half are overweight or obese.

From a nutrition point of view, those are exactly the people you’d want to be eating a lean, healthy protein like fish.

So Duperval is concerned about sending mixed messages.

“I do think it is confusing. And, it’s in part, I think, how we communicate crisis in this country, especially when it comes to food safety. They miss the overall preventative message, that fish is good food, and it actually provides a lot of important nutrients that are lacking in their diets.”

Health authorities often issue advisories about certain fish that have a lot of pollution.

Duperval says understanding those warnings can help people avoid some of the hazards.

But the diabetes research shows we may still have a lot to learn about these chemicals, so what’s safe to eat is getting harder to know.

For The Environment Report, I’m Gabriel Spitzer.

Close Contact Endangers Dolphins

More people are feeding dolphins and getting too close to them in their boats. (Photo courtesy of Mote Marine Laboratory)
This cartoon depicts a dolphin in rehab, talking to a bear and a raccoon about being addicted to handouts from humans. (Photo courtesy of NOAA)
The effects of dolphins getting too close to fishing boats: an injury to a dolphin's tail fluke caused by fishing line. (Photo courtesy of Mote Marine Laboratory)

Television dolphins like Flipper
and the performing dolphins at
Sea World can trick people into
thinking it’s okay to feed and
swim with wild dolphins. But
Rebecca Williams reports dolphin
researchers say our behavior can
hurt and even kill dolphins:

Transcript

(sound of a shorebird crying out)

Fort Myers beach is packed with tourists. I meet a guy named Justin who’s here in Florida from Cleveland. He’s already gotten close to wild dolphins.

“We were out here swimming and dolphins got within a foot of us. It was amazing. I’ve never seen that.”

In this case, he wasn’t doing anything wrong – because the dolphins came up to him. But swimming with wild dolphins can actually be considered harassment if you approach them or touch them.

That’s bad for the dolphins because it can change their behavior. It can disturb their feeding and resting behavior. And it can separate dolphins from their babies.

So it’s illegal to swim with or harass dolphins. You can get fined and even end up with some jail time. And that’s just the beginning of the dolphins’ problems.

Dolphin encounters are getting more common in Florida and Hawaii and a lot of other places. There’ve been more tourists and more boaters in the water… and more commercial operations that promise you’ll get a chance to feed or swim with dolphins.

As cool as it might be for us, it’s actually terrible for dolphins. When people feed them they can get addicted to human handouts.

Cartoon Dolphin PSA: “For me it started with one hit of sardines, oh sardines… that’s where I learned to beg. It was easy to score free fish… with this dolphin smile? Yeah it’s illegal but no one cares…”

That’s a cartoon dolphin in rehab with a bear, a raccoon and a seagull. All those other animals we’ve gotten into some bad habits with.

It’s a message put out by the Mote Marine Laboratory in Sarasota.

(sound of dolphin playing in tank at the Marine Lab)

Randall Wells is the head of dolphin research at the lab. He’s spent almost four decades studying dolphins.

He says, in recent years, there’s been a dramatic increase in the number of dolphins getting into trouble with people. More people feeding them and getting too close to dolphins in their boats.

“And we’ve seen an increase in mortality from these kinds of interactions – from people luring animals in towards boats, in towards fishing gear. Dolphins have begun to take bait from lines getting tackle including hooks and lures in their bodies and killing them or seriously injuring them.”

He says, if you feed a dolphin, it’ll often start begging for food from people. And that dolphin will teach its babies or other dolphins to beg.

Sometimes they’ll even eat things that aren’t food. One dead dolphin had a plastic snake in its stomach.

If dolphins get closer to boats, they can get snared in fishing line. It can slice through their flippers. Once, Randall Wells rescued a dolphin that had a Speedo on its head. And because it couldn’t shake it off, the suit was cutting into the dolphin’s flesh.

Wells and his team have been doing a lot of outreach to stop people from getting too close to dolphins. And he says most of the time, it works.

“But there’s still a half percent of people that, by their own admission, insist on interacting with these animals – feeding them and approaching them in ways that are illegal, just because they can and they’ve never seen the negative consequences of doing that.”

If you want to go on one of those dolphin viewing tours, there are some ways to make sure the tour operator’s not adding to the problem.

Stacey Horstman helps run a program called Dolphin Smart. It certifies dolphin tours as responsible.

Right now there are only four businesses in Key West and one in Alabama that’ve gotten certified. But, she says, if you’re in a place without Dolphin Smart tours, you can still ask questions.

“Just to make sure that feeding is not being promoted in any way, that they’re promoting responsible viewing from a distance.”

That means staying at least 50 yards away from dolphins.

She says any ad that shows people swimming with dolphins or handing them fish is usually a sign of an irresponsible business. So those are ones to stay away from.

Dolphins might look cute and friendly, but Horstman says they are wild animals and they need their space.

For The Environment Report, I’m Rebecca Williams.

Jellyfish Taking Over Oceans?

A jellyfish under the Ross Sea ice, on October 14, 2005 (Photo by Henry Kaiser, courtesy of the National Science Foundation)

Some scientists are warning
that as overfishing and climate
change affect the world’s oceans,
jellyfish will take over the
ecosystem. That could mean that
eventually, if you cast a net
into the ocean all you’d haul
in would be jelly blobs. But
as Ann Dornfeld reports, such
warnings may be premature:

Transcript

The theory goes like this. Overfishing is removing the main jellyfish predators from the oceans. And warming oceans could be more hospitable to jellies.

A new report published in the journal Trends in Ecology and Evolution says jellyfish are already taking over. Its authors point to recent big jellyfish blooms as evidence.

But not everyone’s convinced.

“I think there’s a set of people that are sensationalizing the jellyfish bloom issue.”

University of Washington researcher Claudia Mills has been studying jellies for 30 years.

“I do think that probably jellyfish blooms are on the increase. But the problem is, we have so little baseline data that it’s almost impossible to really, honestly know that.”

Mills says there’s hardly any historical data on jellyfish populations, and not even much recent data.

She says it could be that the future of the world’s oceans is gelatinous and tentacled… or the blooms could just be cyclical.

For The Environment Report, I’m Ann Dornfeld.

The Case of the Disappearing Dolphin

A false killer whale, which is actually a type of tropical dolphin, with calf (Photo by Deron Verbeck, courtesy of iamaquatic.com)
(Photo by Robin Baird, courtesy of cascadiaresearch.org)

Commercial fishing in the oceans of the US has done a lot to reduce
accidentally catching marine mammals such as dolphins. But there are
still problems. Ari Daniel Shapiro reports on concerns about one kind
of tropical dolphin called the false killer whale:

Transcript

Jim Cook has been a fisherman in Hawaii for 18 years.

“You know, it used to be real simple: catch a fish, sell it, and go
back out and try and catch another one.”

Now he owns a company that operates six fishing vessels. Cook’s
ships catch deep swimming sashimi-grade tuna that ends up in sushi
restaurants across the US. They use a technique called longline fishing.

“We have around 45 miles of mainline to which we attach floaters
and 2200 to 2500 baited hooks.”

“The regulations imposed on the Hawaii longline fishery are
probably the most restrictive regulations on any longline fishery in the
world.”

That’s Bill Robinson. He’s an administrator with the National
Marine Fisheries Service. And these regulations he’s talking about are
meant to reduce bycatch. That means catching marine animals other than
the tuna. As a result of these policies, sea turtle bycatch has dropped
by more than 90-percent and seabird bycatch by 95-percent.

Things are looking up, but now there’s another problem. The numbers of
another kind of animal – the false killer whale – are declining. No one
knows why they’re disappearing. It might be related to longline
fishing, but it’s just not clear.

Robin Baird’s a biologist with Cascadia Research.

“There’s a whole variety of lines of evidence that imply the false
killer whale population around the main Hawaiian islands has declined
dramatically over the last 20 years. And I think it’s clearly the most
serious conservation or management issue for whales and dolphins in
Hawaiian waters today.”

Baird thinks the decline is partly related to fewer numbers of tuna
and other species false killer whales eat. He also suspects that the
false killer whales might be moving farther offshore, where they could
get hooked when trying to eat the tuna caught by the longline fishery.

So the question is: should the National Marine Fisheries Service come up
with even more regulations for the longline fishery in case more false
killer whales move offshore looking for tuna.

Bill Robinson with the Fisheries Service isn’t so sure that they
actually go that far offshore.

“That’s speculation, and it may or may not be true. What we
don’t really know is what the range of each population is.”

So, really, at this point, it’s anyone’s guess why the false killer whale numbers are declining.

The biologist, Robin Baird, is concerned that nothing’s being done.

“Unless something is done to change the factors that are
influencing the population, it probably will continue to decline.”

The environmental group Earthjustice and a coalition of
conservation groups have sued the National Marine Fisheries Service over
failing to develop a plan to protect the false killer whales.

The agency has not responded officially to the lawsuit yet. But Bill
Robinson says an action plan is in the works.

“Hopefully by the fall, we’ll be able to not only appoint the
team, but have the team begin work on a take recovery plan that will
make recommendations to the agency to reduce the incidental take of
false killer whales in the fishery.”

Such a plan might end up costing the commercial fishers money. But
Jim Cook says he’s willing to pay. That’s because false killer whales
pick fish off his lines. They eat the caught tuna before the fishers
can haul them in. That can mean a lot of lost income.

“We would very much welcome any methodology almost
irrespective of cost because we’re suffering quite a bit economically as
it is.”

But the National Marine Fisheries Service first has to find that
methodology.

For The Environment Report, I’m Ari Daniel Shapiro.

Tuna Farming in the Ocean

They call the cages Oceanspheres. They’d have the diameter of half a football field. (Photo courtesy of Hawaii Oceanic Technology)

A company in Hawaii wants to build the world’s first commercial bigeye tuna farm. Bigeye tuna is also known as ahi and it’s a popular fish for sushi. Rebecca Williams has more:

Transcript

A company in Hawaii wants to build the world’s first commercial bigeye tuna farm. Bigeye tuna is also known as ahi and it’s a popular fish for sushi. Rebecca Williams has more:

Bigeye tuna are getting overfished in the wild.

So a company called Hawaii Oceanic Technology wants to raise tuna in giant underwater cages off the coast of Hawaii.

They call the cages Oceanspheres. They’d have the diameter of half a football field.

Bill Spencer is president and CEO of the company. He says they’ll raise 20,000 fish in each cage. The tuna will get up to 100 pounds each.

“They’re typically a schooling type fish so they’d be able to swim around in the Oceansphere so we think that would give them the ability to get the kind of muscle tone that would be appreciated by the consumers.”

There are real concerns about pollution and that fish will escape and spread disease to wild fish.

Spencer says ocean currents will sweep away fish feces so they won’t concentrate, and he says the cages are built so tuna can’t escape.

For The Environment Report, I’m Rebecca Williams.

Saving Salmon From Sea Lions

Bobby Begay has been patrolling the Columbia River below Bonneville Dam for the past three years, hazing sea lions. (Photo by Sadie Babits)
Robin Brown is a marine mammal researcher for the Oregon Department of Fish and Wildlife. (Photo by Sadie Babits)
Bobby Begay and his crew on board the Columbia River Inter-Tribal Fish Commission boat. (Photo by Sadie Babits)

The Columbia River in the Pacific Northwest historically has been a super highway for salmon. But dams, development, and pollution have taken their toll on salmon. The fish have declined to the point that several species are endangered. Now the salmon face another threat, sea lions. As Sadie Babits reports wildlife managers are trying to get rid of the sea lions to protect the salmon:

Transcript

Bobby Begay steers his small boat up the Columbia River. He knows this river, and he
knows the salmon. His ties to the salmon go back generations.

As a member of the Yakima Tribe, he comes out here to tribal fishing sites to catch
salmon. It’s something Indians along the Columbia River have been doing for thousands
of years. He says the salmon are considered sacred food.

“It’s part of our livelihood. It’s part of our health and well being.”

They use the salmon to feed everyone from the tribal elders to the children. Tribal
fishermen tell stories of seeing so many salmon in the Columbia River that you could
walk across their backs. Those days are gone.

A series of dams on the river make it hard for fish to get from the Pacific Ocean to fresh
water and back again. The salmon have fallen victim to over-fishing, agricultural
pollution, and habitat destruction. Pacific salmon are now listed as endangered. And they
face yet another threat on the Columbia River – sea lions.

“Sea lions have probably always been in the Columbia but not to this extent and have
done damage to salmon populations like it has and all of it is due because of a man-made
structure, which is Bonneville Dam.”

Sea lion numbers have exploded along the Pacific Coast. And more than a thousand of
them travel up the Columbia River looking for food. Some of them have figured out that
if they gather at the base of Bonneville Dam, they can easily catch salmon that are trying
to pass by.

Biologists estimate that every year sea lions eat some 13,000 salmon. This year, the
federal government gave state wildlife agencies in Oregon, Washington and Idaho, the go
ahead to kill up to 85 sea lions.

Begay won’t really talk about whether he thinks this is right. He’s torn.

“Well, ah, sea lion is a spiritual animal not only to us but to coastal tribes and we respect
the animal as it is, but also the salmon is a scared food to us as Columbia River Indians.”

So Begay works to protect the salmon without killing the sea lions. He works for the
Columbia River Inter-Tribal Fish Commission.

That’s why he’s out here in this boat. He patrols the river most days using fireworks to
scare sea lions away from the salmon.

Crew: “There he is 1 o’clock, 50 yards.”

(sound of gun shots and boat)

Begay’s crew shoots firecrackers over the sea lion.

“And hopefully we’ll get them into the main stem of the river and start hazing them down
stream.”

“The hazing really is not highly effective. The animals are really quick to learn.”

Robin Brown is a marine mammal researcher for the Oregon Department of Fish and
Wildlife.

Brown says they’ve euthanized seven sea lions this year. He says the decision to kill a sea
lion is made after everything else has failed.

“We have to have observed them killing salmon and steelhead, and they have to have
been exposed to all the non-lethal methods of harassment that you’ve observed here
today and shown that that isn’t detouring them from being here and feeding.”

The Humane Society opposes killing the sea lions. It’s asked the courts to put a stop to it.
While this legal battle plays out, Bobby Begay will keep hazing the sea lions until the end
of May.

That’s when the sea lions leave the dam and head back down the Columbia River to the
Pacific Coast to breed.

For The Environment Report, I’m Sadie Babits.

Bringing a Fish Back From the Brink

The American Shad became so rare that hatcheries had to help restore depleted populations (Photo courtesy of the US Fish and Wildlife Service)

A million year old cycle of fish migration almost came to an end in the waters off of the nation’s capital. But a monumental conservation effort has brought them back from the brink. Sabri Ben-Achour explains:

Transcript

A million year old cycle of fish migration almost came to an end in the waters off of the nation’s
capital. But a monumental conservation effort has brought them back from the brink. Sabri Ben-
Achour explains:

I bet you can’t recognize this sound.

It is the sound of a female shad – it’s a type of fish – having its eggs squeezed out into a metal
bowl.

“In the bowl, it looks like applesauce.”
That’s biologist Catherine Lim. We are on a boat in the middle of the Potomac, 20 miles south of
Washington DC, harvesting and fertilizing shad eggs. Lim picks up a male shad and gives it a
squeeze.

“Yeah, he sprayed out there.”

She mixes the brew around and adds water.

“We’ll bag them up and send them to the fish hatchery.”

This is all part of an effort to restore the population of the American Shad. For millions of years,
the large silver-iridescent fish have swum in from the Atlantic and up the rivers of the East Coast
every spring to spawn. They return to the same place where their lives began, guided by a
unique geological odor that seeps from the earth and mountains that feed each river.

Once upon a time – only a century ago – these fish were so numerous they turned the water silver
and made rivers move.

At least that’s what Jim Cummins says, he’s a biologist.

“On the Susquehanna, there were so many of them they created a wave as they came up the
river, a standing wave.”

On the Potomac they fueled entire industries. According to newspaper reports, Washington DC
exported 4 million barrels of salted shad every year in the 1840’s.

“The wagons would come into Georgetown were so heavy that they crammed up the city – I think
it’s the first report of gridlock in Washington.”

The fish fed more than just commerce – they nourish everything from crabs to dolphins. Bald
Eagles actually evolved to time their egg laying early, so their chicks would hatch just as the Shad
and their relatives appeared in the river. And then came overfishing, dams, and pollution.

“In the 1960’s, there were times when the migratory fish came up to spawn in the area and met
that pollution, and hundreds of thousands of them died and made a stinking mess.”

The clean water act was passed in 1972, but by 1980, the fish were almost wiped out. A
moratorium on fishing at the time was too little too late. Water quality gradually improved as
waste water treatment plants were upgraded and aquatic grasses returned. But still, no Shad.

So Cummins began the Shad restoration project.

They had to use several nets – each hundreds of feet long – just to catch one fish. They got help
from fisheries and even elementary schools. Dams were fixed to let fish go around them. The
Shad population exploded.

At a boat house just outside of DC, anglers Steve Bocat and Louis Covax are enjoying success
that up until recently, few alive have seen here.

“It was great we had incredible fishing. I mean, between the two of us, we had, what, 50-60 fish
up to the boat?”

Another sign of success, a pair of Bald Eagles recently returned to the area following the fish –
the first in decades.

For The Environment Report, I’m Sabri Ben-Achour.

Water Pollution Feminizing Fish

Chemicals in the water are mixing up fish's gender (Photo courtesy of US Fish and Wildlife Service)

Scientists already know estrogen from things like ‘The Pill’ is getting into the water and causing reproductive problems for fish. Male fish are picking up female attributes. Some males are even growing eggs. Now a study finds there are other chemicals getting into water that might be messing with fish gender even more. Rebecca Williams reports:

Transcript

This study’s found a group of chemicals that block the male hormone testosterone is getting into rivers.

Charles Tyler is the lead author of the paper in the journal Environmental Health Perspectives.

He says they don’t know exactly where these chemicals are coming from, but some medicines and pesticides can block testosterone. So, add that to the estrogen…

“And so it’s very likely they’re going to have interactive and additive effects, if you like, to induce a double whammy on the poor fish.”

Tyler says they don’t know if what’s happening in fish is also happening in people.

Human male fertility has been declining. But there might be other chemicals contributing to the problem.

And besides, there’s a difference. Fish can’t get away from these testosterone blocking chemicals or the estrogen in the water – they live and swim in them. So Tyler says they’re getting a much higher dose.

For The Environment Report, I’m Rebecca Williams.

Throwing the Big Fish Back

Fishing laws in Canada and US states often protect small fish and are less restrictive with big ones. (Photo courtesy of the US Fish and Wildlife Service)

People who love to fish spend plenty of money on gear, license fees and even gas for their boats. It’s enough to make anglers think, maybe they’re entitled to keeping the biggest fish for trophies or the frying pan, right? Shawn Allee met a researcher who wants you to throw back your biggest catch:

Transcript

This is the guy who wants to change how a lot of people fish.

“My name is Paul Venturelli and I study fisheries biology at the University of Toronto.”

Venturelli’s disturbed by how many fish species are on the brink of collapse – either in oceans or in fresh water.

He hopes to grow fish stocks – with this fishing advice.

Toss the big ones back.

And what’s he got to back that up?

“I’ve got about ten pages of notes here. Nah, I’m kidding. I’m kidding.”

Actually, he says the idea is pretty simple.

“A ton of big, old fish will produce more new fish than a ton of smaller, younger fish. And this is because the bigger, older fish tend to produce offspring that have a higher chance of survival.”

Venturelli studies mostly ocean-species, but he says the principal should apply to North American freshwater fish like pike and walleye, too.

But Venturelli’s got a problem spreading this idea around.

Fishing laws in Canada and a lot of US states often protect small fish and are less restrictive with big ones.

I asked one of the head guys in Illinois fisheries, Joe Ferencak, why that is.

“Essentially what you’re doing with that minimum size limit is protecting one or two year classes of reproductive age fish so they can successfully spawn or reproduce.”

Ferencak says, fisheries science has stood behind the ‘protect the small fish’ theory for decades – with some exceptions.

He says to change laws, Venturelli would need to do more studies.

Plus, Ferencak says no state would want to completely keep people from big fish – that’s just not much fun.

“We want to maintain and enhance these fisheries for the benefit of the fishing public, the angler. And it’s kind of counter-intuitive to not allow them to take these larger fish.”

Well, I figure it wouldn’t be fair to talk about big fish without talking to outdoorsmen, so I spent some time in Griffith, Indiana.

It’s about ten miles from Lake Michigan.

Fishing and hunting outlets are all around – and there’s this place.

Allee: “So what’s the establishment.”

Leap: “American Natural Resources.”

Edward Leap Senior runs American Natural Resources – it’s a taxidermy shop – with stuffed deer, fox, and fish filling every nook and cranny.

I figure Leap would rush to the defense of catching big fish, but, you know what? He doesn’t bite.

Allee: “If you get a whole bunch of fish in your boat, I mean, you want to show off the big one. Most people do, right?”

Leap: “Yes and no, though. When you get talking about the conscientious outdoorsman, no, he’s not going to be thinking this way. He’s going to say, ‘I got this fifteen pound walleye, a super-trophy fish. It took a lot of years to grow this fish, I’m going to take a picture of it and I’m going to release it.'”

And, to prove the point, he reaches back and pulls a fish trophy off the shelf.

“For the trophy part of it, we’ll do a reproduction of it that you can’t tell from the real thing. And the fish now is out there spawning, and making eggs, and continuing its species.”

Leap says more and more fishermen are having him make fake fish – or, reproductions, as he calls them.

So, from his vantage, scientists like Paul Venturelli won’t have too much trouble with the advice to ‘throw back the big ones.’

Leap says you don’t have to keep fish you catch, and in his experience, smaller fish make better eating anyway.

For The Environment Report, I’m Shawn Allee.

Tag: fishes

Population Control for Cormorants

Transcript

Related Links

Great Lakes Fish Linked to Diabetes

Transcript

Related Links

Close Contact Endangers Dolphins

Transcript

Related Links

Jellyfish Taking Over Oceans?

Transcript

Related Links

The Case of the Disappearing Dolphin

Transcript

Related Links

Tuna Farming in the Ocean

Transcript

Related Links

Saving Salmon From Sea Lions

Transcript

Related Links

Bringing a Fish Back From the Brink

Transcript

Related Links

Water Pollution Feminizing Fish

Transcript

Related Links

Throwing the Big Fish Back

Transcript

Related Links