Friday, August 29, 2008
Thursday, August 21, 2008
Threats and Conservation
A large number of parrot species are in decline, and several species are now extinct. Of the 350 or so living species of parrot 130 species are listed as near threatened or worse by the IUCN.[32] There are numerous reasons for the decline of so many species, the principal threats being habitat loss, hunting, and for some species, wild-bird trade. Parrots are persecuted for a number of reasons; in some areas they may (or have been) hunted for food, for feathers, and as agricultural pests. For a time, Argentina offered a bounty on quaker parakeets (an agricultural pest), resulting in hundred of thousands of birds being killed, though apparently this did not greatly affect the overall population . Capture for the pet trade is a threat to many of the rarer or slower to breed species. Habitat loss or degradation, most often for agriculture, is a threat to numerous parrot species. Parrots, being cavity nesters, are vulnerable to the loss of nesting sites and to competition with introduced species for those sites. The loss of old trees is particularly a problem in some areas, particularly in Australia where suitable nesting trees may be many hundreds of years old. Many parrot species occur only on islands and are |vulnerable to introduced species such as rats and cats, as they lack the appropriate anti-predator behaviours needed to deal with mammalian predators. Controlling such predators can help in maintaining or increasing the numbers of endangered species. Insular species, which have small populations in restricted habitat, are also vulnerable to physical threats such as hurricanes and volcanic eruptions.
Trade, export and import of all wild-caught parrots is regulated and only permitted under special licensed circumstances in countries party to CITES, the Convention on the International Trade in Endangered Species, that came into force in 1975 to regulate the international trade of all endangered wild caught animal and plant species. In 1975, 24 parrot species were included on Appendix I of CITES, thus prohibiting commercial international trade in these birds. Since that initial listing, continued threats from international trade have lead CITES to add an additional 32 parrot varieties to Appendix I, including nine in the last four years. All the other parrot species are protected on Appendix II of CITES. In addition, individual countries may have laws to regulate trade in certain species.
There are many active conservation groups whose goal is the conservation of wild parrot populations. These groups tend to be supported the most by pet owners who care deeply about parrots. One of the largest includes The World Parrot Trust, an international organization. The group gives assistance to worthwhile projects as well as producing a magazine and raising funds through donations and memberships. They state they have helped conservation work in 22 countries. On a smaller scale local parrot clubs (or hookbill clubs as they're called,) will raise money to donate to a cause of conservation. Zoo and wildlife centers usually provide public education, to change habits that cause damage to wild populations. A popular attraction that many zoos now employ is a feeding station for lories and lorikeets, where visitors feed small parrots with cups of liquid food. This is usually done in association with educational signs and lecture.
Trade, export and import of all wild-caught parrots is regulated and only permitted under special licensed circumstances in countries party to CITES, the Convention on the International Trade in Endangered Species, that came into force in 1975 to regulate the international trade of all endangered wild caught animal and plant species. In 1975, 24 parrot species were included on Appendix I of CITES, thus prohibiting commercial international trade in these birds. Since that initial listing, continued threats from international trade have lead CITES to add an additional 32 parrot varieties to Appendix I, including nine in the last four years. All the other parrot species are protected on Appendix II of CITES. In addition, individual countries may have laws to regulate trade in certain species.
There are many active conservation groups whose goal is the conservation of wild parrot populations. These groups tend to be supported the most by pet owners who care deeply about parrots. One of the largest includes The World Parrot Trust, an international organization. The group gives assistance to worthwhile projects as well as producing a magazine and raising funds through donations and memberships. They state they have helped conservation work in 22 countries. On a smaller scale local parrot clubs (or hookbill clubs as they're called,) will raise money to donate to a cause of conservation. Zoo and wildlife centers usually provide public education, to change habits that cause damage to wild populations. A popular attraction that many zoos now employ is a feeding station for lories and lorikeets, where visitors feed small parrots with cups of liquid food. This is usually done in association with educational signs and lecture.
Sunday, August 17, 2008
Friday, August 8, 2008
Sound Imitation and Speech
Many species can imitate human speech or other sounds, and the results of a study by Irene Pepperberg suggested a high learning ability in an African Grey Parrot named Alex. Alex was trained to use words to identify objects, describe them, count them, and even answer complex questions such as "How many red squares?" with over 80% accuracy. A second example is that of N'kisi, another African grey, which has been shown to have a vocabulary of approximately a thousand words and has displayed an ability to invent as well as use words in context and in the correct tense.
Parrots do not have vocal cords, so sound is accomplished by expelling air across the mouth of the bifurcated trachea. Different sounds are produced by changing the depth and shape of trachea. So, talking parrots are really whistling in different variations. Congo African Grey Parrots (CAG) are well known for their ability to "talk", which may be caused by more control, or stronger trachea. But that does not mean that a Cockatiel (Cockatiels are not well known for their talking ability), could have a greater vocabulary than an African Grey Parrot.
Parrots do not have vocal cords, so sound is accomplished by expelling air across the mouth of the bifurcated trachea. Different sounds are produced by changing the depth and shape of trachea. So, talking parrots are really whistling in different variations. Congo African Grey Parrots (CAG) are well known for their ability to "talk", which may be caused by more control, or stronger trachea. But that does not mean that a Cockatiel (Cockatiels are not well known for their talking ability), could have a greater vocabulary than an African Grey Parrot.
Friday, August 1, 2008
Wednesday, July 23, 2008
Behaviour
Parrots have a strong, direct flight. Most species spend most of their time perched or climbing in tree canopies. They often use their bills for climbing by gripping or hooking on branches and other supports. On the ground parrots often walk with a rolling gait.
Tuesday, July 15, 2008
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