Invasive Species

Carp Could Stir Up Trouble In Nipissing

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Note: this article refers to the common carp and does not refer to the “Asian Carp” a species of fish presently contained to the Mississippi River system. The Asian carp has made its way to the Illinois River near Chicago, but strong efforts are being made to keep the Asian Carp from reaching Lake Michigan and the Great Lakes. See http://www.epa.gov/glnpo/invasive/asiancarp/

  
An unwelcome species of fish has made its presence known to Lake Nipissing anglers.
 

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A carp was caught last year near West Bay, said Richard Rowe, a biologist with Nipissing First Nation.

"I don't know when they came or how many there are, but they're here," Rowe said Wednesday, following a presentation to the Lake Nipissing Stewardship Council on the Nipissing Nation Fishery Management Program.

"What concerns me is that carp eat the bottom weeds and stir up the mud on the bottom of the Lake, which is where pike and muskie lay their eggs."

According to the Ministry of Natural Resources website, carp can be identified by the whiskers beside their mouths and their one dorsal spine. They live in the Great Lakes region from the upper St. Lawrence River to Lake Superior and in many inland lakes, reservoirs and rivers.

John Thornton, president of the stewardship council, said it's the council's job to help educate lake users about invasive species.

He said carp isn't the only invasive species in Lake Nipissing - black crappie and spiny water fleas are not native to the area.

"Black crappie was introduced by people several years ago who weren't catching walleye or they could have come into the area from a bait bucket," Thornton said, noting the spiny water flea has been on the radar since 2000, but has so far has not created a problem in Lake Nipissing.

Thornton said that can't be said for bass, which have invaded some area lakes where lake trout once thrived, competing for limited food sources.

"Other lakes in the area have mistakenly been implanted with bass by people who thought they were food for lake trout," he said.

Thornton said once a species has been introduced, there is little that can be done to eradicate it unless nature decides it's inappropriate.

  

Spiny Water Fleas Invade Nipissing

By PJ WILSON, THE NUGGET
May 27, 2011
 
The surface of Lake Nipissing is smooth as glass as the small boat pulls up next to a buoy about seven kilometres from the North Bay Marina.
 
Richard Rowe, the fisheries biologist with Nipissing First Nation, eases the throttle back while Jean-Marc Filion carefully sets his capture net in the water, paying out the rope as the boat crawls forward.
 
When the boat passes the second buoy, about 150 metres ahead, Rowe stops the engine and Filion begins to pull in the net. It's a long net, with a fine mesh of about 300 microns. He is after one specific species, and he is finding it in abundance.
 

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There are thousands in the bottom of the net. In the first of three passes, at a depth of one metre, there were upwards of 4,000.  In the second pass, at a depth of five metres, there were a few less and the third and final pass, at a depth of about 10 metres, there were probably less than 3,000.  The catch is almost entirely spiny water fleas. There is very little daphnia, which at one time had a huge population in the lake.  





  
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The spiny water flea is an invasive species brought to North America from the Baltic Sea in the bilge water of ships.  What we've seen is that since May 30, most of the other zooplankton has disappeared," Filion says.  The change has been so abrupt that it was astonishing. The first testing found a good mix of zooplankton and the spiny water fleas.  But the fleas, he explains, are voracious eaters. Within three weeks, there were only the fleas and one other zooplankton member being caught in any significant numbers.
 
The concern, he says, is that the flea is changing the entire bio-system of the lake. The entire biology of Lake Nipissing is being reorganized," Filion says. This is pretty serious."  He calls it the second dangerous invader to North American lakes, second only to the zebra mussel, in changing a lake's ecosystem.  The daphnia have completely disappeared," he says.  The spiny water flea is a carnivore, while most zooplankton is herbivorous. That means fish species that formerly ate the daphnia and other zooplankton have had to adjust.
 
Filion says the fish have begun to adjust. Perch are gorging on the spiny water fleas and their population is expanding. One of the many questions, though, is what is happening to the walleye.
 
Rowe, an employee of Nipissing First Nation (until 2011), conducts a census of the walleye population to determine how much fish can be caught by the commercial fishery. For 12 years, the walleye population was growing at a steady rate, but last fall there was a sudden decrease.
 
Rowe ordered a 10% decrease in the walleye catch by native fishermen.
 
While Filion agrees with the reduction, though, he admits the data might be off. The census catch is made with nets set on the bottom of the lake. But, if the walleye have moved to a new food source, one higher up in the water column, the census nets would be missing the fish.

One of the most striking observations, though, has been how thoroughly the spiny water flea has moved into Lake Nipissing.
 
In (1988 or 1989) Kevin O'Grady and I found one spiny water flea in Lake Nipissing," Filion says. We went to see the Partners in Conservation and told them we had the potential for change."  He said a study was launched at that time to look at the zooplankton structure in the lake, prior to the spiny water flea arriving in major numbers.  The spiny water flea numbers have increased over the years.
 
At the beginning of the sampling season this year, there was still a large daphnia population.
On Sunday, there were few things other than spiny water fleas in the capture net.
 
Another concern is that as the spiny water flea dines on herbivorous zooplankton, the plant life that would normally be consumed is being left alone.
 
That, he speculated, could be behind the algal blooms that have been reported in Lake Nipissing, Callander Bay and Cache Bay.
 
Sampling will continue on Lake Nipissing through the summer. At this time there is only one testing area being used, but in July, Filion and other volunteers will be sampling from eight basins spread around the lake, including the French River.  He hopes the invader can be kept out of Trout Lake, although this will require cooperation from boaters and anyone else using the lakes.
 
He said anyone moving a boat from Lake Nipissing to Trout Lake should chlorinate the bilge water and take measures to ensure they don't carry the invader from one lake to the other.
We don't want it in Trout Lake," he says. It is bad enough that it is in Lake Nipissing."
 
Posted: 5/27/2011
  

VHS Virus Spreading 

This following AP article by W. Kates appeared May 23, 2007 in the North Bay Nugget and a variety of other publications. The UFRCA previously posted an article on Jan. 27, 2007 (see below following the May 23 article) regarding the threat of the VHS virus locally. Bait fish from southern Ontario are now banned from sale, but anglers may still legally transport them to the area. Visitors are urged to use locally caught bait fish only.
 
MNR Large Lake Biologist Scott Kaufman made the following remarks in an e-mail May 25, 2007:
 
As of now, Lake Nipissing is considered VHS-free, however it was identified as a 'high risk' lake for infection. Thus it is now part of a provincial surveillance program. It is scheduled for bi-annual testing, the first of which occurred about 2 weeks ago (we won't see results for a while, yet). The next round of testing will occur in the autumn.

We have also built some questions regarding the use of live bait into our regular creel survey (when we interview anglers and find out how much fishing/harvest is going on). It is our opinion that this will be the most likely source of infection, since historically, most baitfish were harvested from the great lakes.

As far as the French River goes, I am pretty sure that HWY 69 is the technical boundary to VHS positive classification. Anything downstream of the highway is considered positive. Anything upstream is okay.

The jury is still out on the severity of threat VHS poses to the resource. Some say we are in big trouble; some say fish will develop immunity. I would rather not find out.
 
 
Aquatic virus hits 2 Great Lakes
By WILLIAM KATES, Associated Press Writer
 
A deadly, fast-spreading aquatic virus is reaching epidemic proportions in New York's two Great Lakes and has already spread into the Finger Lakes region in upstate New York, a Cornell University fisheries expert said Tuesday.
 
The viral hemorrhagic septicaemia virus — or VHS — has now been identified in 19 species in Lake Erie and Lake Ontario, including muskellunge, New York's No. 2 sport fish, said Paul Bowser, a professor of aquatic animal medicine in the College of Veterinary Medicine.
 
Equally alarming, said Bowser, is the confirmation of VHS in walleye in Conesus Lake, which is the westernmost Finger Lake and is the only New York lake where VHS has been confirmed in a body of water other than the contiguous waters of the Great Lakes.
 
"The fact that VHS was found in this inland body of water is particularly disturbing in that it immediately brings up the question of how did it get there and what can be done to prevent the virus from moving to other bodies of water," said Bowser, who along with his colleagues at Cornell recently developed a new test that can identify the virus within 24 hours.
 
VHS was first detected in New York last year in fish from the St. Lawrence and Niagara rivers, as well as the state's two Great Lakes.
 
Of the 19 species affected, VHS has caused serious fish kills in six, Bowser said. In the remaining 13 species, Cornell scientists have detected the virus but have recorded no "mortality events," he said. There are approximately 150 species of freshwater fish in New York.
 
"It has been found in a broad range of evolutionarily distinct species, both cold- and warm-water families. We don't think there is any species that is not susceptible," said Doug Stang, chief of the New York Department of Environmental Conservation's Bureau of Fisheries, which is monitoring 40 water bodies across the state to track the spread of VHS.
 
Bowser said he suspects that the virus is spread by airborne or terrestrial predators carrying infected fish, anglers using infected bait minnows or contaminated fishing equipment, and as a result of boating activities.
 
"Basically, we don't know how it got here, but it's here and it's spreading," said Bowser.
 
The virus, which causes internal bleeding in fish but poses no threat to humans, was discovered in the United States in 1988 in Coho and Chinook salmon in the Pacific Northwest. VHS made its first known appearance in the Great Lakes in 2005, killing freshwater drum and muskellunge.
 
Since then, it has been found in more than two dozen fish species throughout the Great Lakes basin.
 
This month, the Wisconsin Department of Natural Resources made a preliminary identification of the virus for the first time in the Lake Winnebago chain of inland lakes about 25 miles south of Green Bay on Lake Michigan. Confirmation is pending.
 
VHS-related die-offs killed millions of fish in Lake Erie and Lake Ontario last year. There have been three new fish kills this year in New York waters, Bowser said.
 
In the St. Lawrence River, hundreds of thousands of round gobies have succumbed and gizzard shad die-offs occurred in Lake Ontario west of Rochester and in Dunkirk Harbour on Lake Erie, he said.
 
"In that most of our VHSV-associated fish kills in 2006 were in May and June, we expect more to occur," Bowser said.
 
Other species that have tested positive include bluegill, rock bass, black crappie, pumpkinseed, smallmouth and largemouth bass, northern pike, yellow perch, channel catfish, brown bullhead, white perch, white bass, emerald shiner, blunt nose minnow, freshwater drum and burbot.
 
Containing the spread of the virus in New York will require restrictions on the movement of live fish, testing fish and surveillance, Bowser said.
 
"There will be inconveniences and disruptions that will occur. However, to do nothing could be disastrous," said Bowser, adding that VHS threatens the state's $1.2 billion sport-fishing industry and could have a devastating effect on aquaculture.
 
Last year, New York enacted a series of emergency regulations to curb the virus' spread, such as requiring that bait fish be used in the same body of water from which they were collected unless they have been tested. Those regulations will likely become permanent next month, said DEC spokeswoman Maureen Wren.
 
Fish-killing virus present in Lake Huron; MNR worries disease will spread North

CP/Nugget Staff/AP
Local News - Friday, January 26, 2007 Updated @ 11:02:59 AM

A fast-spreading aquatic virus threatening stormy waters for the Great Lakes fishing industry has been detected in Lake Huron for the first time, Michigan officials said Thursday.

The state Department of Natural Resources said it had confirmed the presence of viral hemorrhagic septicaemia, or VHS, in fish samples from waters as far north as Cheboygan - only about 25 kilometres from where Lake Huron meets Lake Michigan.

VHS previously had been found in only two of the Great Lakes - Ontario and Erie - and in Lake St. Clair, which links lakes Erie and Huron. But officials have predicted the virus eventually would spread across the entire lakes system, where the US $4.5-billion fishery is a crucial segment of the economy.

"This disease threatens the closure of a major portion of the Michigan baitfish industry," said Chris Weeks, president of the Michigan Aquaculture Association.
 
 
The Ontario Ministry of Natural Resources has banned North Bay area bait dealers from selling Lake Erie's emerald shiners to prevent the spread of VHS, a disease known to cause die-offs in walleye, musky and perch populations

However anglers travelling to North Bay can legally possess 120 live bait fish from anywhere in the province, including the infected and buffer zones in southern Ontario, and there is no law that stops them from bringing the potentially infected fish to the area.

John Cooper, a spokesman for the MNR, confirmed Wednesday anglers could spread the virus because of current sport fishing regulations and admitted the MNR was helpless to stop that threat in time.

How damaging the virus turns out to be will depend largely on whether fish develop immunity to it, said Kelley Smith, chief of the DNR's fisheries division.

The virus poses no danger to people but is deadly for fish. It targets some of the region's most popular sport and commercial species.

Analyses completed earlier this week found VHS in whitefish from the Cheboygan area, whitefish and walleye from Thunder Bay, and Chinook salmon from a DNR egg-taking station near Rogers City, Smith said.

Originally a saltwater virus, VHS made its first known appearance in the Great Lakes in 2005, killing the likes of freshwater drum and muskellunge.

The Cheboygan-area whitefish were collected in 2005 during a survey for bacterial kidney disease, Smith said. They were examined again more recently and found to have carried VHS.

How VHS arrived in the lakes is uncertain. But fishery managers said a likely culprit is ballast water dumped by ocean freighters, widely considered a leading source of exotic species in the lakes.

"These new discoveries are extremely unfortunate and further highlight the problems created by the constant introductions of new diseases from outside the Great Lakes region," DNR Director Rebecca Humphries said.

The U.S. Department of Agriculture last October banned interstate shipments of 37 species of live fish from the Great Lakes region in hopes of checking the spread of VHS and keeping it out of inland waters.