The main nesting area was in the region of the Great Lakes and east to New York. The main wintering sites stretched from Arkansas to North Carolina south to the uplands of the Gulf Coast states. The habitat of the passenger pigeon was mixed hardwood forests. The birds depended on the huge forests for their spring nesting sites, for winter "roosts," and for food. The mainstays of the passenger pigeon's diet were beechnuts, acorns, chestnuts, seeds, and berries found in the forests. Worms and insects supplemented the diet in spring and summer.
In the winter the birds established "roosting" sites in the forests of the southern states. Each "roost" often had such tremendous numbers of birds so crowded and massed together that they frequently broke the limbs of the trees by their weight. In the morning the birds flew out in large flocks scouring the countryside for food. At night they returned to the roosting area.
Their scolding and chattering as they settled down for the night could be heard for miles. When the food supply became depleted or the weather conditions adverse, the birds would establish a new roosting area in a more favorable location. The migratory flights of the passenger pigeon were spectacular. The birds flew at an estimated speed of about sixty miles an hour. Observers reported the sky was darkened by huge flocks that passed overhead.
These flights often continued from morning until night and lasted for several days. The time of the spring migration depended on weather conditions. Small flocks sometimes arrived in the northern nesting areas as early as February, but the main migration occurred in March and April. The nesting sites were established in forest areas that had a sufficient supply of food and water available within daily flying range. Since no accurate data were recorded on the passenger pigeon, it is only possible to give estimates on the size and population of these nesting areas.
A single site might cover many thousands of acres and the birds were so congested in these areas that hundreds of nests could be counted in a single tree. A large nesting in Wisconsin was reported as covering square miles, and the number of birds nesting there was estimated at ,, The nests were loosely constructed of small sticks and twigs and were about a foot in diameter.
A single, white, elongated egg was laid per nesting. The incubation period was from twelve to fourteen days. Both parents shared the duties of incubating the egg and feeding the young. The young bird was naked and blind when born, but grew and developed rapidly. When feathered it was similar in color to that of the adult female, but its feathers were tipped with white, giving it a scaled appearance. It remained in the nest about fourteen days, being fed and cared for by the parent birds.
By this time it had grown large and plump and usually weighed more than either of its parents. It had developed enough to take care of itself and soon fluttered to the ground to hunt for its food. Authorities differ as to how many times the passenger pigeon nested in a season. The general opinion was that the birds normally nested twice in a season, but this can neither be proved nor disproved since no accurate records of nestings were made.
During the late summer the flocks of passenger pigeons frequently moved about at random in the northern forests in search of food, but as fall approached and temperature changes became sharp the flocks of passenger pigeons began their migration to the southern wintering areas. Because the passenger pigeon congregated in such huge numbers, it needed large forests for its existence.
When the early settlers cleared the eastern forests for farmland, the birds were forced to shift their nesting and roosting sites to the forests that still remained. As their forest food supply decreased, the birds began utilizing the grain fields of the farmers. The study provides strong evidence that a combination of natural selection and hunting contributed to the extinction of the passenger pigeon. Why did the most abundant bird in the world go extinct in just 50 years?
CBC Radio Loaded. The passenger pigeon numbered in the billions but went extinct very quickly because of low genetic diversity as well as being widely hunted. Social Sharing. Quirks and Quarks Why did the most abundant bird in the world go extinct in just 50 years? This made the population fragile, and when humans hunted them further, shooting and trapping them, they managed to exterminate the entire species.
Image bank - click on the pictures for more information. Find out more: All you need to know about passenger pigeons Passenger pigeon fact file Learn more about Martha Learn more about other extinct birds Print out your own passenger pigeon image page PDF , Kb. Find out about the extinct and endangered animals in the Museum. Dodo Coelacanth Thylacine Blue whale Golden toad Giant panda Passenger pigeon Schaus' swallowtail Go to the Homepage to find out about hippos and the causes of extinction.
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