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We've made some changes to EPA. A century ago, a bird called the passenger pigeon lived in North America. There were so many passenger pigeons that people often saw great flocks of them flying overhead containing thousands, even millions, of birds. Today, there is not a single one left. The passenger pigeon became extinct. All living passenger pigeons disappeared from the earth entirely. The passenger pigeon became extinct for two reasons. First, the forests where it lived were cut down to make way for farms and cities.
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Second, many pigeons were shot for sport and because they were good to eat. At that time, there were no hunting laws to protect endangered species like there are now. There are over 1, endangered or threatened species in the United States today. Endangered species are those plants and animals that have become so rare they are in danger of becoming extinct.
Threatened species are plants and animals that are likely to become endangered within the foreseeable future throughout all or a significant portion of its range. Species disappear because of changes to the earth that are caused either by nature or by the actions of people. Sometimes a natural event, like a volcano erupting, can kill an entire species.
Other times, extinction will happen slowly as nature changes our world. For example, after the Ice Ages, when the glaciers melted and the earth became warmer, many species died because they could not live in a warmer climate. Newer species that could survive in a warmer environment took their places. People can also cause the extinction of plants and animals. The main reason that many species are endangered or threatened today is because people have changed the homes or habitats upon which these species depend.
Drowning in plastic — Plastic pollution has rapidly accelerated, with eight million tons entering the marine environment each year, according to scientists. This figure is set to rise as production of the material is set to double over the next 20 years. Burning problem — In many of the worst affected countries such as China and the Philippines , local people lack the infrastructure to properly dispose of plastic waste. In some cases they burn it, releasing dangerous gases associated with cancer. Plastic people — There are also concerns that people are consuming dangerous plastic through contaminated fish.
A survey published in Scientific Reports journal revealed that a quarter of market fish in Indonesia and California contain plastic. Picking up the pieces — There are different ideas about how to address the crisis. National and Atmospheric Association favors beach cleaning and public education at local level, combined with challenging policymakers and plastic producers to promote conservation. Recycling efforts are becoming more creative. Plastic waste is now converted into building materials in Cameroon and the Philippines.
Charging for plastic bags and bottles and bags has helped to reduce waste. Far out — Dutch entrepreneur Boyan Slat has a more ambitious vision. He has designed a huge trash-eating machine that he intends to deploy at the Great Pacific Garbage Patch. In the report, the rapid extinction is blamed on habitat loss, over exploitation of resources, pollution and climate change.
American robin
Among the species mentioned in the report are elephants, whose numbers have fallen by a fifth in ten years, as well as sharks and rays, a third of whom face extinction from overfishing. The American robin is active mostly during the day and assembles in large flocks at night. Its diet consists of invertebrates such as beetle grubs , earthworms , and caterpillars , fruits, and berries. It is one of the earliest bird species to lay eggs, beginning to breed shortly after returning to its summer range from its winter range.
Its nest consists of long coarse grass, twigs, paper, and feathers, and is smeared with mud and often cushioned with grass or other soft materials. It is one of the first birds to sing at dawn, and its song consists of several discrete units that are repeated. The adult robin is preyed upon by hawks , cats, and snakes.
When feeding in flocks, it can be vigilant, watching other birds for reactions to predators. Brown-headed cowbirds Molothrus ater lay eggs in robin nests see brood parasite , but the robins usually reject the eggs. This species was first described in by Carl Linnaeus in the twelfth edition of his Systema Naturae as Turdus migratorius.
The term robin for this species has been recorded since at least Though having distinct plumage , the two species are similar in vocalization and behavior.
Beyond this, it lies in a small group of four species of otherwise Central American distribution, suggesting it recently spread northwards into North America. Seven subspecies of American robin are recognized. These subspecies intergrade and are only weakly defined. The robin has a brown back and a reddish-orange breast, varying from a rich red maroon to peachy orange. The sexes are similar, but the female tends to be duller than the male, with a brown tint to the head, brown upperparts and less-bright underparts.
However, some birds cannot be accurately sexed on the sole basis of plumage. Despite being depicted in the film Mary Poppins "feathering its nest" in London, [17] this species is actually a rare vagrant to western Europe, where the majority of records, more than 20, have been in Britain.
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Vagrants to Europe, where identified to subspecies, are nominate T. The American robin's breeding habitat is woodland and more open farmland and urban areas. It becomes less common as a breeder in the southernmost part of the Deep South of the United States, and there prefers large shade trees on lawns.
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Birds in central California of the subspecies propinquus are considered to be still increasing their range, and this is probably the case elsewhere in the U. The American robin is a known reservoir carrier for West Nile virus. While crows and jays are often the first noticed deaths in an area with West Nile virus, the American robin is suspected to be a key host, and holds a larger responsibility for the transmission of the virus to humans.
This is because, while crows and jays die quickly from the virus, the American robin survives the virus longer, hence spreading it to more mosquitoes, which then transmit the virus to humans and other species. The American robin is active mostly during the day, and on its winter grounds it assembles in large flocks at night to roost in trees in secluded swamps or dense vegetation. The flocks break up during the day when the birds feed on fruits and berries in smaller groups.
During the summer, the American robin defends a breeding territory and is less social. The American robin's diet generally consists of around 40 percent small invertebrates mainly insects , such as earthworms , beetle grubs , caterpillars and grasshoppers , and 60 percent wild and cultivated fruits and berries. They will flock to fermented Pyracantha berries, and after eating sufficient quantities will exhibit intoxicated behavior such as falling over while walking. Robins forage primarily on the ground for soft-bodied invertebrates, and find worms by sight and sometimes by hearing , [25]: In some areas, robins, particularly of the coastal race T.
The robin uses auditory, visual, olfactory and possibly vibrotactile cues to find prey, but vision is the predominant mode of prey detection. In addition to hunting visually, it also has the ability to hunt by hearing. Experiments have discovered that it can find worms underground by simply using its listening skills.
In urban areas, robins will gather in numbers soon after lawns are mowed or where sprinklers are in use. Occasionally, they may visit bird feeders if mealworms or animal-fat suet is offered. Juvenile robins and eggs are preyed upon by squirrels , snakes, and some birds, such as blue jays , Steller's jay , common grackles , American crows , and common ravens. Overall, 28 raptorial bird species are known to hunt robins.
However, when feeding in flocks, the American robin is able to remain vigilant and watch other flock members for reactions to predators. The American robin is known to be a rejecter of cowbird eggs, so brood parasitism by the brown-headed cowbird is rare.
Sixth mass extinction? Two-thirds of wildlife could be gone by - CNN
Even when it occurs, the parasite's chick does not normally survive to fledging. The American robin begins to breed shortly after returning to its summer range. It is one of the first North American bird species to lay eggs, and normally has two to three broods per breeding season, which lasts from April to July. The nest is most commonly located 1. The outer foundation consists of long coarse grass, twigs, paper, and feathers.
This is lined with smeared mud and cushioned with fine grass or other soft materials. A new nest is built for each brood [ citation needed ] , and in northern areas the first clutch is usually placed in an evergreen tree or shrub while later broods are placed in deciduous trees. Robins are not cavity nesters, and so will generally not use a bird house , but will take advantage of artificial nesting platforms. A clutch consists of three to five light-blue eggs , and is incubated by the female alone.