The Toronto and Region Conservation Authority (TRCA) said it was notified in May that the birds began showing up near Blockhouse Bay and Long Pond near the Hanlan’s Point ferry deck on the west end of the Toronto Islands. “There was a big increase in cormorants in early June. And so we took immediate action to develop a kind of short-term mitigation strategy,” said Andrea Chreston, the TRCA’s project manager for Tommy Thompson Park. Residents of the island are concerned about the damage the birds are causing to the trees. They also don’t like the distinct smell from the cormorant’s fish and excrement-based diet. The TRCA says it is working to prevent them from nesting and expanding their footprint. However, some experts say that given the proximity to Tommy Thompson Park on the Leslie Street Spit, their arrival on the islands is no surprise.
Back from near extinction
Cormorants are a native species that declined in the 1800s due to hunting and came close to local extinction in the 1970s and 1980s due to the use of the insecticide DDT. The largest double-crested cormorant breeding colony in North America is now located at Tommy Thompson Park. Last year, the population was estimated at 12,000 birds. TRCA manages the colony and works to contain the area where they nest because their acidic droppings can damage trees. A close-up of a cormorant. It is a native species that has come close to extinction. (Evan Mitsui/CBC) “The droppings rain down and change the soil chemistry. So the nutrients are no longer readily available in the soil that the tree needs to absorb,” Chreston said. “And over time, the tree’s health declines.” But their droppings aren’t the only problem. Chreston says cormorants can strip trees of their leaves by repeatedly nesting in them over a period of years. He says TRCA is also trying to create nests on the ground to encourage birds to stay away from trees. Double-crested cormorants are seen at Leslie Street Spit in Tommy Thompson Park, where tree damage is visible. TRCA has used various measures to prevent their spread to other parts of the park. (Laura Pedersen/CBC) He says when they learned the birds were starting to nest on Toronto Island, they moved quickly. “We removed immature nests during June to the point where we were no longer seeing cormorants trying to build new nests,” Chreston said. As it is now the end of the breeding season, Chreston says conservation workers will return in a few months when the birds fly south for the winter and remove all the nesting material so that when the cormorants return next spring , will be empty. A colony of double-crested cormorants was spotted near Hanlan’s Point in the Toronto Islands this week. (Laura Pedersen/CBC) “We want to encourage the cormorants that have been nesting on the Toronto Islands to come and nest on the ground at Tommy Thompson Park.”
View of residents
Some residents on the Toronto Islands still aren’t sure what to do with the birds. “We have people who really care about the environment and some of them are not so concerned because they are local [species]. Others are really worried that they’re destroying the environment,” Tony Farebrother told CBC News, pointing to damaged trees near Blockhouse Bay. Tony Farebrother, president of the Toronto Island Community Association, poses for a portrait in front of a group of trees double-crested cormorants have taken to breed on the Toronto Islands near Hanlan’s Point. (Laura Pedersen/CBC) Farebrother, who is the president of the Toronto Islands Community Association, says it’s the first time in his 26 years on the island that he’s seen them nesting there. Although the area where they nest is a few kilometers away from residential areas, he says he receives letters of complaint. “The fact that they are here is less of a concern – because they are quite far from us – the interest will be whether they continue to spread and discourage other animals and damage trees.” The opinions of other residents of the island are clearer. Gordon Ballantyne, general manager of Toronto Island Marina, poses for a portrait on his boat in Blockhouse Bay at Hanlan’s Point seawall in the Toronto Islands A colony of double-crested cormorants nests in a group of trees nearby. (Laura Pedersen/CBC) “This is certainly a new addition, but not a welcome one,” said Gordon Ballantyne, general manager of Toronto Island Marina. He says residents started spotting them in April. Ballantyne says their distinct fishy smell is the most obvious sign of their arrival, but that’s not all. “They are a nuisance bird in that they kill the trees they nest in. They come in large numbers. They overwhelm the area in terms of killing the fish population to some extent because that’s what they eat,” he said. . Ballantyne says he and other residents worry about whether efforts to prevent the birds from nesting on the islands will work. “[The TRCA] they say they’ve managed to stabilize the population so it doesn’t grow anymore. It feels like they’re still expanding in the immediate area.”
Expert advocates ‘tolerance and long-term planning’
It is not clear why the birds ended up nesting near Hanlan’s Point. Gail Fraser, a cormorant expert, speculates that it may be due to the colony’s proximity to the spit of islands, the remote nature of the area they have settled in, or that they followed another species to the site. “It’s surprising that it took this long for cormorants to appear on the Toronto Islands,” said Fraser, who is a professor in the school of environment and urban change at York University. Gail Fraser is a professor in the School of Environment and Urban Change at York University in Toronto. (Laura Pedersen/CBC) Fraser says it will take a lot of time and effort to keep the birds from returning, especially now that they are already nesting there. “I think it’s going to be several years before we get there early and really scare them. Because… right when they arrive, that’s when they’re scattered, that’s the time to really scare them.” A cormorant is pictured above the treetops at Leslie Street Spit. (Evan Mitsui/CBC) Fraser says the public may not be inclined to tolerate cormorants, but adds that it’s important to note that they are a native species that has recovered from near extinction. “I would like to encourage some tolerance and long-term planning.”
