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Introduced Mammals On Seabird Breeding Islands
Seabirds include some of the most threatened taxa anywhere in the world. For example, of extant albatross species, 82% are listed as threatened, endangered, or critically endangered by the International Union for Conservation of Nature.Save the Albatross Campaign. 9 February 2011. Species at Risk. Save the Albatross; a global campaign by BirdLife International. Retrieved 25 February 2011 The two leading threats to seabirds are accidental bycatch by commercial fishing operations and introduced mammals on their breeding islands. Mammals are typically brought to remote islands by humans either accidentally as stowaways on ships, or deliberately for hunting, ranching, or biological control of previously introduced species.Safina, C. 2008. The state of our seabirds, p. 1-24. In J. Hardesty, S. Holmer, M. J. Parr, D. Pashley, G. Radko, G. Shire, and G. E. Wallace ds. Bird Conservation, the magazine of the American Bird Conservancy. The Plains, VA.Harris, D. B. 2009. Review of negative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seabirds
Seabirds (also known as marine birds) are birds that are adaptation, adapted to life within the marine (ocean), marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding ecological niche, niches have resulted in similar adaptations. The first seabirds evolved in the Cretaceous geological period, period, and modern seabird families emerged in the Paleogene. In general, seabirds live longer, Reproduction, breed later and have fewer young than other birds do, but they invest a great deal of time in their young. Most species nest in Bird colony, colonies, which can vary in size from a few dozen birds to millions. Many species are famous for undertaking long annual bird migration, migrations, crossing the equator or circumnavigating the Earth in some cases. They feed both at the ocean's surface and below it, and even feed on each other. Seabirds can be hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shearwaters
Shearwaters are medium-sized long-winged seabirds in the petrel family Procellariidae. They have a global marine distribution, but are most common in temperate and cold waters, and are pelagic outside the breeding season. Description These tubenose birds fly with stiff wings and use a "shearing" flight technique (flying very close to the water and seemingly cutting or "shearing" the tips of waves) to move across wave fronts with the minimum of active flight. This technique gives the group its English name. Some small species, like the Manx shearwater are cruciform in flight, with their long wings held directly out from their bodies. Behaviour Movements Many shearwaters are long-distance migrants, perhaps most spectacularly sooty shearwaters, which cover distances in excess of from their breeding colony on the Falkland Islands (52°S 60°W) to as far as 70° north latitude in the North Atlantic Ocean off northern Norway. One study found Sooty shearwaters migrating nearly a yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Local Extinction
Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a change in the ecology of an area. In recent times, local extinction has sometimes been followed by a replacement of the species taken from other locations; wolf reintroduction is an example of this. The term "local extinction" is highly vernacular. The more proper biological term is ''extirpation''. Discussion Glaciation can lead to local extinction. This was the case during the Pleistocene glaciation event in North America. During this period, most of the native North American species of earthworm were killed in places covered by glaciation. This left them open for colonization by European earthworms brought over in soil from Europe. Species naturally become extirpated from islands over time. The number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
