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Black Robin

2007 Schools Wikipedia Selection. Related subjects: Birds

                   iBlack Robin

                             Conservation status

   Endangered (EN)
            Scientific classification

   Kingdom: Animalia
   Phylum:  Chordata
   Class:   Aves
   Order:   Passeriformes
   Family:  Petroicidae
   Genus:   Petroica
   Species: P. traversi

                                Binomial name

   Petroica traversi
   ( Buller, 1872)

   The Black Robin or Chatham Island Robin Petroica traversi is an
   endangered bird from the Chatham Islands off the east coast of New
   Zealand. It is closely related to the New Zealand Robin.

   Petroica traversi is a sparrow-sized bird. Its plumage is almost
   entirely brownish-black, unlike its mainland counterparts, and as it
   evolved in the absence of predators, its flight capacity is somewhat
   reduced. In the early 1980s only five Black Robins survived but were
   saved from extinction by Don Merton and his team, and by "Old Blue",
   the last remaining female.

   All of the surviving black robins are descended from "Old Blue",
   unfortunately giving little genetic variation among the population and
   creating an extreme population bottleneck. Interestingly, this seems to
   have caused no inbreeding problems, leading to speculation that the
   species has passed through several such population reductions in its
   evolutionary past and thus losing any alleles that could cause
   deleterious inbreeding effects. It was generally assumed that the
   minimum viable population protecting from inbreeding depression was
   around 50 individuals, but this is now known to be an inexact average,
   with the actual numbers being below 10 in rapidly-reproducing
   small-island species such as the Black Robin, to several hundred in
   long-lived continental species with a wide distribution (such as
   elephants or tigers).

   The species is still endangered, but now numbers around 250 individuals
   in a single population on tiny Little Mangere Island. Ongoing
   restoration of habitat and eradication of introduced predators is being
   undertaken so that the population of this and other endangered Chatham
   endemics can be spread to several populations, decreasing the risk of
   extinction by natural disasters or similar stochastic events.

   The binomial commemorates the New Zealand botanist Henry H. Travers
   (1844–1928).
   Retrieved from " http://en.wikipedia.org/wiki/Black_Robin"
   This reference article is mainly selected from the English Wikipedia
   with only minor checks and changes (see www.wikipedia.org for details
   of authors and sources) and is available under the GNU Free
   Documentation License. See also our Disclaimer.
