Cormorants: varmints of bird world

They're wily, voracious and can dive and swim like submarines and thus are excellent fishers.

They also stink, and areas where they nest in tightly packed colonies are reduced to fetid graveyards of skeletal trees and dead vegetation by their acidic feces.

The population of double-crested cormorants, protected in Ontario for more than three decades, has exploded to the point where it is now considered the varmint of the bird world.

While the cormorant population in Hamilton Harbour and Cootes Paradise appears to be steadily declining, the Ministry of Natural Resources has decided to carry out another cull of the pesky birds in the Presqu'ile Point area this year after an independent scientific study determined the population needs to be suppressed.

Last year in a test cull, ministry officers used a full range of actions including egg oiling, nest removal, electronic harassment and shooting to reduce the population by 6,000 birds. Another 5,500 will be targeted this year at Presqu'ile.

"What we have here is nature totally out of balance," says Robert Pye, communications co-ordinator for the Ontario Federation of Anglers and Hunters.

Their numbers were reduced almost to zero in the 1970s by high levels of DDT and other contaminants in the Great Lakes. But since DDT was banned, scientists estimate that the population is now in excess of 500,000 and the birds consume 42-million pounds of fresh water fish annually.

Pye says the population is increasing alarmingly and the cormorant should lose its protected status to allow landowners to deal with them on their own.

The OFAH maintains that the birds are destroying the sport fishery in Ontario, an important tourist attraction. Michigan and New York State are also concerned about the effect of the overpopulation and have started culling the birds.

Pye says a study conducted by Cornell University in Ithaca, N.Y., found a direct link between the growing cormorant population and a 58 per cent decline in sport fish such as walleye and yellow perch. However, John Hall, co-ordinator of the Hamilton Harbour Remedial Action Plan, says there are not as many cormorants sticking around Hamilton as there used to be.

Annual surveys of nesting pairs on Hickory Island in Cootes Paradise have shown a steady decline since 1998 when there were 218 pairs nesting on the small island, says Carl Rothfels, the natural lands steward for the Royal Botanical Gardens. By 2004, that number had declined to 68 pairs.

Rothfels adds that two years ago, there were 15 active nests around the shore of Carroll's Bay in the northwest end of the harbour, but last year all the nests were abandoned.

Hall says over the past few summers, residents in the Indian Point area of Burlington who are downwind of two small rock islands in the bay inhabited by the birds had complained about the terrible stench that wafts over their land.