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Cormorants: The bird everyone loves to hate

Flap, flap, flap, glide. Flap, flap, flap, glide. I watch as it skims along the surface of Ramsey Lake. The bird is low to the water and level as it is making its way to the islands near the middle of the lake.
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Double-crested cormorants are fishers, and very good at it. They're quite capable of eating a coarse fish such as yellow perch and a plump fish like the brown bullhead. Supplied photo.
Flap, flap, flap, glide. Flap, flap, flap, glide. I watch as it skims along the surface of Ramsey Lake. The bird is low to the water and level as it is making its way to the islands near the middle of the lake. There are a few rocks that protrude out of the water surface and are just perfect for perching.

The rock is frequently used by herring gull, common merganser and the occasional bald eagle, but few birds can be more controversial than this flier. They are about the size of a small Canada goose, another regular to the local lakes.

When flying they reveal the streamlined body that seems to have evolved just for the purpose of smooth flight. They don’t just fly in the air however. They are proficient divers, and move under water in loon-like fashion.

It is here that the controversy starts. They are fishers, and very good at it. They're quite capable of eating a coarse fish such as yellow perch and a plump fish like the brown bullhead.

Ramsey Lake should be quite capable of accommodating these needs. The availability of alewives in Lake Ontario may have helped in the population growth. Research on prey types has shown the alewife, yellow perch and other coarse fish as their primary diet.

One of the group features is the presence of a gular sac. An expandable orange yellow sac attached to the lower mandible that can collect larger prey than is sometimes thought possible.

A long beak with a hook-like tip helps in the capture of prey; into the mouth it goes and either on the water or to a nearby perch the swallowing begins. Prey size and struggles dictate how long the swallowing process may take.

This bird has specialized tail feathers that are long and stiff and are excellent rudders in under water manoeuvres. The wings are long and somewhat rounded for propulsion in air. The legs are positioned further back to the body which provides for the strong under water swimming antics.

Decades ago, DDT caused a drastic population decline and with the banning of the insecticide in the early seventies the population made a slow recovery. In Sudbury some of the first resident birds seen in recent times started around 1987.

Today, this species can be seen daily, in small numbers on many of the local lakes. When they ride on the water they can be confused with loons. However, their dark bodies and upright beak stance help to identify them from far away.

Nesting occurs on islands in the North Channel and on small islands within the Great Lakes.

Double-crested cormorants get their name from the head gear they have during courtship. Specialized black or white feathers stand out on the sides of the head giving the bird a regal appearance during the courtship season. Take the time to watch them swim, as they can be very entertaining.

Chris Blomme is an executive member of the Sudbury Ornithological Society and works with animals at Laurentian University. Have a question for Chris? Send it to [email protected].

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