Goldfish, nets and electric streams: inside the cool war of Canada against invasive carp
Steel whiskers like your bow with long -term wires, like a research vessel of fisheries department and oceans. Nobilis A strange metal resembles catfish. Below, waving the electric pulses through the Grand River, was marked by only a stable beep and nets, which is ready to write, invasive goldfish and rudd were shocked. These fish are not going back.
This is how the calm war of Canada is waged against the aggressive carp: with the electro check, underwater net, nets and serious efficiency of euthanasia. The DFO provided a special access to CBC News to join a patrol as the crew scanned the river for aggressive fish, rarely seen as part of an early identity attempt.
The bets are high. Inventory carp can consume insects every day in aquatic vegetation and insects, which can bare the wetlands in aquatic vegetation and insects. Once fully developed, they average 40 kg – make them larger, hungry and highly disruptive. Wildlife biologists warn that if one of the four aggressive Asian carp species takes advantage of setting a leg in a Canadian water, it will permanently change the ecosystem of great lakes.
“This is a high -risk area for us,” told CBC News by Alex Price, a senior biologist of DFO’s aggressive carp program. “We haven’t found a grass carp with our program this year, but this is a good sign. It tells us that there are very few grass carp in water we are taking samples.”
Although they are not breeding in Canadian rivers, they are at the door of the country. American researchers found evidence of fish breeding in the Central Basin of Lake Eri last year. It forms the Grand River, the largest river system of the Southern Ontario, a major goal for grass carp that is looking for swimming and spawn upwards.
Grand River A ‘High-Risk Area’
The first grass carp caught in Canadian Waters was found on Grand near Dunville in 2013, after which two more were captured in the same stretch of the river.
They are of the increasing number of these fish, which have been excluded from lakes Ontario, Eri, Huran and even lakes. St. Lawrence River in QuebecNorth -East of Montreal. Overall, DFO has processed 34 grass carp since 2012, 21 of which were sterile, able to reproduce another 11. Two were found dead on a coastline and went to tell very far.
When DFO catches a fish during a patrol, they are then placed in a holding tank so that scientists can see closely. Once, each fish is measured methodically, logged and photographed. The native species, such as the Largemouth Bass, are placed back, while aggressive species such as goldfish or European minanose are ejected.
Price states that the DFO’s aggressive carp program has a two -fold mission: grass changes forever by one of the world’s most destructive fish to catch and destroy and destroy the carp and document the native ecosystems.
It is an important part of the logging operation. DFO crew pre-infections are documenting the native ecosystem, knowing that the entire Great Lex watershed can be on the verge of irreversible changes.
“The data we collect is very important,” the value said. “This allows us to see what the fish community in these water are, and if the grass carp is installed, we will have a good pre-pre-post-detta set of what the effects of grass carp are actually.”
Only one time
Currently Canadian water has no established population of aggressive carp, but the DFO crew knows that it is only a matter of time before that change. The reproductive population has been established in Ohio, in the first Sanduski River in 2016So Mauomi River in 2018their Recent discovery in lake eri The attack further puts Canada in the list.
“There is no doubt about this,” Nicholas Mandark, a biology professor, said, who study endangered and aggressive fish species at the University of Toronto-Sarkoro. He said that the fish discovered in Ohio 10 years ago will soon be much larger to travel many hundreds of kilometers north.
“The question is whether we can prevent them from spreading inside the Canadian tributaries,” he said, researchers have identified 100 river systems with the Great Lake Basin that will provide the ideal habitat for grass carp.
Mandrak said that the DFO is out of there, looking at the first place to prevent the invasion, which not only makes the aggressive carp program important, but rare, because there are some agencies in the world that work to prevent the arrival of an aggressive species.
He said, “The installation of grass carp in Great Lex will be frightening,” he said, in the 1960s, fish was introduced by humans as a cheap way to remove vegetation from Aquaculture ponds. However, they have proved so fierce that after cleaning the ponds, farmers often resort to cabbage.
“Their purpose is to control vegetation. Vegetation is what makes our wetlands. Those wetlands are central houses for our original species.”
In other words, the introduction of grass carp would be like being a party for another one and a party, which has already grown with aggressive species, creating a tipping point that can push the ecosystem into an unwanted region.
Carp joins the growing artists of aggressive species
The Great Lex is already recovering from herds of aggressive goldfish, zebra and quagga muscles, which have made the green water unlikely to once.
The population of AleWife has increased in some areas because Invasive C lampras have destroyed Removing one of some natural investigations on the rainbow trout population, their number.
Lake eri, shallow of five lakes and Algae blooms in its industry-water western basinOften it is first to show signs of stress. The winter of 2023-24 was almost snow freeAnd this spring brought large-scale people who died on a large scale of temperature-sensitive fish: Litting the coasts of Eliva Lake Eri, washing on the beaches of Gizard Shad Lake Huron.
In early July, there were some areas of the Eri Lake Hot up to 30 cBath water temperature.
Together, indications point to a system under increasing stress, its balance accelerates warming, aggressive species and ecological changes.
Anglers who believe that they catch a grass carp are encouraged to take a photo, pay attention to its place and Contact dfo to report thisOr Ontario attacker species Hotline: 1-800-563-771 or infinvadingspecies.com.
