Floreanaspot thrush
| Floreanaspot thrush | ||||||||||||
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Colored drawing by John Gould |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Mimus trifasciatus | ||||||||||||
| ( Gould , 1837) |
The Floreanaspottdrossel or Charles's mockingbird ( Mimus trifasciatus , Syn . : Nesomimus trifasciatus ) is a kind of the mockingbirds (genus) ( Mimus ) in the family of the mockingbirds (Mimidae). It was endemic to the Galápagos island of Floreana and two small, offshore islands (Champion and Gardner). Human colonization since 1832 brought rats, dogs and cats with it and within 50 years the species was extinct on Floreana. Their natural habitat is subtropical or tropical dry bushland. Their peculiarities gave decisive impulses for Charles Darwin in the development of his theory of the origin of species . Darwin noted the differences between this species and relatives he had observed on the mainland, also noted the exact locations and compared them with other subspecies on the neighboring islands.
Appearance
This species has brown plumage with dark stripes on the back. The neck and chest are a little darker and have brown spots. On the side of the neck there is a large white spot in the back part. The belly is light brown and turns white. The beak is black and slightly bent downwards. The wings are dark brown. The legs and claws on the feet are also black. The red eyes are striking, the eye rims are white and have a very narrow black stripe above and below.
ecology
The breeding biology differs significantly from that of the mainland species. On the Galapagos, the mockingbirds live in permanently expanded groups that defend a common territory. In three of the four species, the dominant pair is supported in the breeding efforts by the other group members. These so-called brood helpers are predominantly, but by no means exclusively, descendants of earlier broods. Unlike other members of the mockingbird family, these birds are unable to imitate the sounds of other birds. Observations show that stocks that were only classified as endangered by the IUCN are dwindling faster and faster. Since 2008, when the world population was only 50 specimens, it has been classified as Critically Endangered as critically endangered. The main threats of this species are introduced house rats , effects of the El Nino phenomenon and diseases such as birdpox .
Conservation breeding program
There are still two small populations on the two islets of Champion and Gardner-by-Floreana. From there, an attempt is made to reintroduce the species to Floreana. According to investigations by the Darwin-Fitzroy collections, the populations appear suitable for this.
Individual evidence
- ^ The Natural World: Galápagos, Islands of Change . BBC Two. Retrieved September 24, 2015.
- ↑ Darwin's mockingbirds knock finches off perch . Archived from the original on March 24, 2014. Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Dominic Couzens: Rare Birds - Survivors, Evolution Losers and the Lost . Haupt Verlag, Bern 2011, ISBN 978-3-258-07629-4 . P. 42.
- ↑ a b http://news.bbc.co.uk/2/hi/science/nature/8364778.stm
literature
- Dominic Couzens : Rare Birds - Survivors, Evolution Losers and the Lost. Pp. 42–45 Haupt Verlag, Bern 2011, ISBN 978-3-258-07629-4 .
Web links
- BirdLife International (BLI) (2008): [2008 IUCN Redlist status changes] . Retrieved May 23, 2008.
- BirdLife Species Factsheet.