speech on Vanishing birds
Answers
Explanation:
hope this answer will help you
Land animals are not the only ones being affected by the loss of habitat and climate change. The issues are taking their toll on birds too. Experts estimate that since the 1500's, over 190 bird species have become extinct. Of these, at least 12 were endemic to North America.
The best known is the passenger or wild pigeon that once accounted for more than a quarter of all birds in North America. Early records tell of the skies turning black for days, when the birds, named after the French word 'passenger' (means 'passing by'), were migrating up and down the North American skies. In 1866, Southern Ontario residents reported seeing a flock that measured one-mile wide and 500 km long. It took the estimated 3.5 million birds, 14 hours, to traverse across the region's skies. Unfortunately, loss of habitat as well as incessant hunting to provide cheap meat for slaves, took a giant toll on these once abundant birds.
Today, the only reminder that the species even existed is thanks to the preserved remains of 'Martha', the last passenger pigeon that died at the Cincinnati Zoo on September 1st, 1914, at the ripe old age of 29! To commemorate her 100-year death anniversary, Martha has been brought out from storage and is currently on display at the Smithsonian National Museum of Natural History, in Washington, D.C.
Also gone are the beautiful Carolina parakeets, the only parrot endemic to North America, the ivory-billed woodpecker - the largest of its kind in the world, and the heath hen, a small wild fowl that was hunted to extinction for food. While not much can be done about these and the others that are already gone, there is still time to save the birds that are currently on the endangered list.
Among them is the tricolored blackbird. Found almost exclusively in California, the beautiful bird that sports a red shoulder patch with a bright white bar, has experienced an 80% decline in population within the last 70 years. Though there are many reasons, one of the biggest is the loss of marsh and foraging habitats along California's coast and Central Valley.
Also on the highly endangered list are one of North America's largest owls - the Northern spotted owl. Deforestation and forest wildfires are the biggest threats to these old-growth forest residents that are extremely territorial and have a hard time adjusting to any disturbance in habitat. The owls are also threatened by the invasions of a larger, hostile and more adaptive relative, the Barred owl, which displaces them by taking over their nests. The fact that some Northern spotted owls have begun breeding with their enemies, resulting in hybrid owls, does not help the situation either.
While efforts to try save them are under way, these are tough species to revive given that they are unable to adapt, need large amounts of open space to hunt and nest and the fact, that females lay only 2-3 eggs each year. Hopefully, environmentalists will be able to at least maintain the current population so that these ancient owls do not disappear completely.
Though they are now considered safe, a drastic drop in their birth rate in 2014, has raised some red flags among biologists. While experts are not sure why so many brown pelicans have abandoned their nests this year, some speculate that it may have something to do with El-Nino - the natural weather cycle that displaces cool water in the Eastern Pacific Ocean with warmer water. This results in disrupting fish populations. While the full effects of the El-Nino are yet to be felt, the smart pelicans may be doing what they have done during previous such years - trailing their food, by flocking to more northerly fishing grounds much earlier than usual.
As global population increases, the issues are only going to get worse. Fortunately, conservationists are more alert now than in the past, and are working hard to preserve the remaining species, so that our skies continue to be filled with these graceful animals.
hope it helps..