| The Thirty-Five Races of the Barn Owl | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 9:59 am | |
| The Thirty-Five Races of the Barn Owl
The Class of Birds (called Aves) consists of 27 different orders. One of these orders, Strigiformes, contains all the worlds owls, and is divided into two families: Strigidae (the so-called true or typical owls) and Tytonidae (known as barn owls).
Overall there are about 216 species of owls, with around 200 in the typical owl family, and 16 species in the barn owl family. The bird most typically known as the barn owl is Tyto alba, which is what we concern ourselves with here.
The diversifying effect of the genetic isolation found on islands is quite evident in the subspecies of Tyto alba: of the 35 races, 20 inhabit only relatively small islands. In fact, the worldwide range of the barn owl is mostly achieved through the ranges of only 11 of its subspecies.
Wherever they live, barn owls remain cavity nesters, are attracted to the structures of man, and also can be attracted to nest boxes. | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 10:01 am | |
| New World Barn Owls
1.North American Barn Owl (Tyto alba pratincola): This is the barn owl of the United States and Central America. This subspecies has one of the largest ranges of any of the races.
2. Central American Barn Owl (T. a. guatemalae): Takes up where pratincola leaves off--ranging through Guatemala, Nicaragua, Salvador, and Panama.
3.Bahamian Barn Owl (T. a. lucayana): Ranges throughout the Bahamas.
4.Cuban Barn Owl (T. a. furcata): Cuba, Grand Caymans, and Jamaica
5. Subandean Barn Owl (T. a subandeana): Contines the range of the barn owl in South America, found in Columbia and Ecuador
6. Columbian Barn Owl (T. a. contempta): Columbia, Ecuador, Peru, and Venezuela. (smallest and darkest of the races)
7. Hellmayr's Barn Owl (T. a. hellmayri): Venezuela into Brazil.
8. Brazilian Barn Owl (T. a. tuidara): Brazil, Chile, and Argentina, completing the range of the barn owl on the South American mainland
9.Tortugan Barn Owl (T. a. glaucops): the islands of Tortuga and Hispanolia in the West Indies
10. Dominican Barn Owl (T. a. nigrescens): the island of Dominica in the West Indies. A very dark race.
11. St. Lucia Barn Owl (T. a insularis): the Lesser Antilles in the West Indies, including St. Lucia, Grenada, and St. Vincent
12. Curacao Barn Owl (T. a. bargei): the island of Curacao off the coast of Venezuela
13. Galapagos Barn Owl (T. a. punctatissima): James Island in the Galapagos Islands. | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 10:03 am | |
| European Barn Owls
1. British Barn Owl (Tyto alba alba): British Isles, France, Switzerland, Italy, Spain, Greece, and North Africa.
2. European Barn Owl (T. a. guttata): Sweden, Denmark, Netherlands, Germany, Poland, Russia, Austria, Hungary, Bulgiaria, and the Crimea
3. Madeiran Barn Owl (T. a. schmitzi): the island of Madeira off the coast of Portugal
4.Ernest's Barn Owl (T. a. ernesti): the islands of Corsica and Sardinia in the Mediterranean | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 10:04 am | |
| African Barn Owls
1.Canary Island Barn Owl (T. a. gracilirostris): eastern Canary Islands off the coast of Africa
2. Cape Verde Barn Owl (T. a. detorta): the islands of St. Vincent and Santiago in the Cape Verde Islands off the coast of west Africa
3. West African Barn Owl (T. a. poensis): the island of Fernando Po off the coast of West Africa
4. Sao Thome Barn Owl (T. a. thomensis): the island of Sao Thome off the coast of West Africa
5. African Barn Owl (T. a. affinis): this very large barn owl is the barn owl of the African mainland, occuring from Gambia in northwestern Africa all the way to the very southern tip of the continent.
6.Madagascan Barn Owl (T. a. hypermetra): even larger than the African, this barn owl inhabits only the large island of Madagascar and the Comoro Islands.
7.Erlanger's Barn Owl (T. a. erlangeri): Saudi Arabia, Lebanon, Syria, Israel, Iraq, and Iran; this is the barn owl being used by the farmers in Israel for integrated pest management. | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 10:05 am | |
| Asian Barn Owls
1. Indian Barn Owl (T. a. stertens): India, Pakistan, Burma, Assam, and Sri Lanka. This owl also has a large range, similar to the European, North American, and African.
2. Burmese Barn Owl (T. a. javanica): Burma, Thailand, Indo-China, and all of South East Asia. The Burmese is being used by oil palm plantations to help control their rodent infestations.
3. Andaman Barn Owl (T. a. de-roepstorffi): a very red race of barn owl that occurs only on the Andaman Islands in the Indian Ocean
4. Sumban Barn Owl (T. a. sumbaensis): only on Sumba Island in Indonesia
5. Kisar Barn Owl (T. a. kuehni): only on Kisar Island in Indonesia
6.Savu Barn Owl (T.a. everetti): only on the the island of Savu in Indonesia | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 10:06 am | |
| Australian Barn Owls
1. New Guinea Barn Owl (T. a. meeki): south-eastern New Guinea and Dampier and Vulcan Islands
2. Boaing Island Barn Owl (T. a. crassirostris): Boaing Island east of New Guinea
3. Santa Cruz Barn Owl (T. a. interposita): Santa Cruz and New Hebrides Islands off the coast of Queensland
4. New Caledonia Barn Owl (T. a. lulu): New Caledonia, New Hebrides, Samoa, Tonga, Fiji, and the Society Islands
5. Australian Barn Owl (T. a. deliculata): Australia, Tasmania, and the Solomon Islands. This race is being used in sugar cane plantations to help control cane, roof, and Norwegian rats. | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 10:08 am | |
| The seventeen species of barn owls are so different than from all the other 200-plus owls in the world that they are placed in their own taxonomic division. This difference is manifested not only in the physiology of barn owls, but also in their behavior. Barn owl species are far more tolerant of man, far more attracted to man-made dwellings, far less territorial, and have much larger broods than most other species of owls.
Barn owls are so tolerant of other barn owls that they will often form colonies. An abandoned steel mill in Utah was discovered to harbor over 30 barn owls that hunted the surrounding area. A single barn in central Florida was recently found to contain 10 pairs of barn owls, all of them raising chicks. It was estimated that these 10 pairs and their young harvested between 15,000 and 25,000 cotton rats from the surrounding sugar cane fields annually.
Barn owls can hear so well that researchers believe they can distinguish which species of rodents they are hearing from the sounds the rodents make as they run along the ground. In one study, it was found that barn owls were capturing pregnant voles at a much higher ratio than existed in the population, showing that they were selecting the fatter voles over the others—most likely through their keen auditory senses.
“For the pocket gopher… barn owls…can represent a substantial biological control that can be manipulated with the placement of barn owl nest boxes around and in the orchard. Research work in California examined contents of barn owl nest boxes in the San Joaquin and Sacramento Valley around prunes, vines and pecans. Results showed pocket gophers represented over 50 percent of the barn owl diet representing an average of 215 gophers ‘taken’ during the breeding and nestling phase….” California Fish and Wildlife Service
Spearheaded by the University of Tel Aviv, Israel has one of the most robust barn owl nest box projects in the world. Communal farms have reported such success with erecting hundreds of nest boxes around the country that Israel’s Ministry of Agriculture has decided to fund and expand the project.
Despite standing over a foot tall with a three-foot wingspan, barn owls weigh only about a pound. This low ratio of weight to wing size allows the barn owl to fly slowly and deliberately over fields while it searches by sight and sound for its prey below.
Recent research shows that young barn owls in the northern states disperse dramatically in the fall. In fact, some birds have flown as far as 1200 miles. But barn owls have traditionally been thought of as sedentary species, having been seen in winter by farmers around in barns going back for decades. It turns out that the young do disperse before their first winter, but it is the adults, who own good territory, that tend to stay. | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 11:04 am | |
| Bahamian Barn Owl (T. a. lucayana): | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 11:34 am | |
| Subandean Barn Owl (T. a subandeana): | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 11:53 am | |
| Hellmayr's Barn Owl (T. a. hellmayri): | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 11:56 am | |
| Dominican Barn Owl (T. a. nigrescens): | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 11:57 am | |
| St. Lucia Barn Owl (T. a insularis): | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
| Subject: Re: The Thirty-Five Races of the Barn Owl Sun Oct 09, 2011 11:58 am | |
| Curacao Barn Owl (T. a. bargei): | |
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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Admin1955 Admin
Posts : 234 Join date : 2011-05-18 Age : 68
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