My brother is a biologists that works with the Ontario government. I can't remember the exact details, but about a decade or so ago he spent an entire summer at the eastern end of Lake Ontario trying to control the out of control Cormorant population I think maybe near Presqu'ile Provincical Park. They started out by poking the nests with long poles and trying to knock some of the eggs out so there wouldn't be as many new chicks. That had zero effect on the population, so they next tried to destroy the entire nesting sites with firehoses. That likewise had a negligible impact. So then ultimately he and his team spent an entire summer shooting every single Cormorant they could with silenced .22 calibre rifles. They had huge piles of dead birds they would put in giant bonfires and burn. Lovely eh? Still didn't make a dent in the overall population. The Province eventually just gave up. I guess Cormorants are like Coyotes, they just can't be culled.
