The debate over cormorants

Many people have noticed an increase in the number of large, black birds on our northern lakes in the past few years. They are cormorants, or to be more precise, Double Crested Cormorants (Phalacrocrax auritus).
Old-timers tell us that they used to be very numerous here years ago, and then they almost disappeared. Now, they are coming back again.
These are large birds, nearly three feet in overall length, and they fly with neck stretched almost straight out in front. Adult birds are almost entirely black but the young have light grey throats and breasts.
Cormorants swim very much like loons–low in the water with head half erect. They dive very quickly from the swimming position, and can stay under for quite some time.
If you are close to an adult bird, you will see a fairly large naked patch on its throat and cheeks, which is coloured orange. In migrating, they fly in an irregular vee, like many of our common geese.
Cormorants have been used for fishing for a very long time. In China and other eastern countries, a ring is placed around the bird’s neck. When it catches a fish and tries to swallow it, the fish cannot get past the ring.
So the fisherman reins in the cormorant back to his boat and takes the fish.
Apparently, these birds become so well trained, and so attached to their masters, that they can be allowed to go fishing on their own. They bring the fish back to the right man in the right boat–just like a retrieving dog.
The same sort of fishing was done for sport, using trained cormorants, in England at the time of Charles I.
Cormorants nest on low rocks, rocky islands, and sometimes low trees. Their nests are very poorly constructed of sticks, sea grasses, and other vegetation. Cleanliness is not a priority with them, and a cormorant colony is usually an evil-smelling area.
It often has big puddles of vile, putrid excrement all around it.
The diet of cormorants, which you might have guessed, is fish. Although some people think cormorants reduce the number of valuable sportfish, all research shows coarse fish make up, by far, the biggest part of these birds’ diet.
In our lakes, sportfish make up only about 10 to 15 percent of their diet. So, in reducing the number of coarse fish, cormorants may very well be helping the population of walleye, trout, bass, and so on.
Cormorants quite commonly stand nearly upright on rocks, buoys, and fallen logs. They also have a habit of standing with their wings spread out about halfway. No one knows why.
This is the only inland cormorant (all of the others are sea birds). The largest colony ever recorded was in Lake Winnipeg, where a small rocky island contained more than 2,000 nests.
This bird is a rather curious relic of the Pleistocene Age–a million or so years ago. Apparently it hasn’t changed very much in all of that time.

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