Like many other species the Roseate Tern is also endangered. These creatures are some of the world’s most beautiful animals and are slowly being killed by man and nature. The Roseate Tern somewhat resembles a sea gull with a slender body and short reddish legs. They have pointed wings and long streamer tails, like the streamer on a kite. Their bodies are a pale gray and are white with a pink tinge on their underside in the early breeding season. This tinge however, is not a good way to tell if a bird is the Roseate Tern since the sun can bleach the colors out. They also have a black forehead and nape. Their upper wings are gray and have distinctly forked wings like that of a swallow. Their wingspan is about 72-80 centimeters and they weigh about 100-120 grams, which is slightly smaller that a mourning dove would be. Both male and female birds are similar in appearance; the only way to tell is that the male that isn’t breeding has a mixed black and white head.
These bird life in quiet areas and live in small colonies. Areas where they can hide easily are taken advantage of. Places with things like dense grasses or other vegetation are the most common nesting sites. If these birds are disturbed in their nesting area, they will most likely abandon the site where their eggs are laid and predators will eat them. The most common areas where these nesting sites are found are in tropical areas such as the Indian, Pacific, Atlantic Oceans, South Africa and Western Australia. They can also like in the hotter areas of North America and Europe.
The Essay on Migrant Bird Population Area Birds
1. Introduction: Population has been increased dramatically for last two decades, and at the same time, the area of wilderness area has been decreased (Geography 210 2001 and The Wilderness Society 1999). Human population, at the same time, distributed broader, which affected the number and size of the fragmented area in the wilderness area (Peter et al. 2000). Migrant birds tend to need large ...
The birds’ population was first dramatically changed in the 1980s when they were hunted for feathers. Due to hunting the population become about 2000 pairs in total. In the 1930s that grew to 10500 due to protective legislation to prevent further damage to the threatened species. Around 1950 again the population went down to only 3800, this time it was due to loss of habitat where the birds had a hard time finding quite nested areas. There are about 50 00 pairs in the world at this time but the population is still gradually decreasing, from both Human disturbance and dominance from larger birds.
The Roseate Tern feeds on mostly small types of salt-water fish. The most common types out of these are Sand Lance, White Hacke, juvenile Herring, Gadids, Cod, Pollock and Haddock. Most of the time they will not fly out of a 20-kilometer radius of the colony to hunt these fish. They will dive into the water, sometimes swimming to catch them. Since Terns live in colonies there tends to be some stealing where other terns will fight another tern that has had a successful catch. Other birds like gulls, being more aggressive attack the smaller terns.
Roseates will hide their young in nests but this will not save them from the many dangers that threaten this species. Larger birds like Gulls, who particularly like to kill the young fledglings, hunt down the Roseate. Since there was a boom in the sea gull population, the birds outnumber the Terns by far. This is because waste from fishing vessels, factories and dumps are the source of the increasing Gull population. and the Gulls use this advantage in taking over the Tern colonies. This leaves the worst nesting spots for the Terns where the young are exposed. Humans will also take valuable nesting space from the Terns without knowing it. After a colony has been made, the Terns can still be disturbed and they will leave their nests where their young will die or be eaten. Such instances where terns leave the nests include, ecotourism, egging, netting of adults and predators that are introduced into the environment. In their winter migration route the birds stay in South Africa for a while. During this time, because it isn’t illegal, the Terns are caught by trappers for food. This is greatly discouraged by the Africa Government but they have no way of stopping them. Conservation efforts include the Canadian ban on trapping in 1917. This is the Migratory Birds Conservation Act which makes it illegal to capture, kill or take nests or eggs. There are also some societies that plant Tern nests on gull free islands so they can grow.
The Essay on Modeling Population Growth
Modeling Population Growth First of all, lets give definition to population growth. The term basically explains how the population changes with time (decreases or increases). It is controlled by the death and birth rates. According to the main ideas of modeling population growth, the rate at which a population changes depends on at least three factors (Modeling Population Growth: Main Ideas, ...
This Bird was never really that great in numbers but those numbers are getting smaller by the day. Without prevention and conservation this bird may never be seen by the generations to come.
Bibliography
1. Environment Canada. Roseate Tern, 1999. 8 December 2000. Available [Online]:
< http://www.cws-scf.ec.gc.ca/hww-fap/roseate/roseate.html> [September 2001]
2. U.S National Biological Service. Roseate Tern Fact Sheet, 1995. March Available [Online]: < http://www.mbr-pwrc.usgs.gov/mbr/tern2.htm> [September 2001]
3.Audubon. Roseate Tern, 2000-2001. Available [Online]
< http://www.audubon.org/bird/species/roseate-tern.html > [September 2001]
4.Birds of America. The Roseate Tern. 1995. Available [Online]
< http://employeeweb.myxa.com/rrb/Audubon/VolVII/00722.html > [September 2001]
