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Pelican vagrancy

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  • Pelican vagrancy

    Morning all

    Perhaps the most difficult job faced by national rarities committees is whether or not to admit 'contentious' species which are considered candidates for vagrancy, yet are kept commonly in captivity. Waterbirds are obviously the major thorny issue, as many exotic species are kept commonly in captivity yet are also excellent candidates for long-distance vagrancy e.g. flamingos, pelicans, Ruddy Shelduck, Baikal Teal etc. Formerly committees were forced to make decisions based on the best available evidence - population trends, numbers kept in captivity, known vagrancy history elsewhere in the range, along with attributes of the individual bird - age, location, behaviour and plumage condition.

    Recent scientific advances have allowed us to assess origin of individual birds by stable isotope analysis (and identification of individuals using molecular-genetic techniques) and now robust statistical analyses allow us to 'pattern seek' within large datasets to look for 'signatures of vagrancy'. These would take the form of predictable occurrence patterns correlated with demographic fluctuations and their abiotic (climatic etc) drivers. Jiguet et al. (2008) [attached] have analysed the extralimital occurence patterns of 3 species of pelican and looked for evidence of natural vagrancy. They have uncovered a predictable (and crucially statistically significant) pattern of occurrence that suggests that at least some of the pelicans occurring in Western Europe are of a wild origin. It would therefore be possible to revisit many records on a case-by-case basis and judge whether or not they occurred in years which were more likely to have produced vagrant individuals which would then add to the individual case for acceptance based on the individual's location, plumage etc...

    Alex
    Attached Files
    Dept. of Zoology, University of Cambridge, UK

    My website - Neotropical Bird Club -Tropical Forest Research - Punkbirder - Wikiaves

    In natural science the principles of truth ought to be confirmed by observation. Carolus Linnaeus

  • #2
    Not that surprising actually as both species seem to be increasing in numbers in Greece and the Balkans in general. Greece now hosts three colonies of Dalmatian (the one in Prespa around 1,000 pairs) and at least one of White (though it could soon be joining the newly established Dalmatian colony in lake Kerkini).

    What really surprises me is that Pygmy Cormorant hasn't become a regular vagrant towards your end of the continent. Flocks at lake Kerkini and Evros delta now exceed 3,000 birds...

    Cheers and Good birding,

    Dimitris

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    • #3
      Very interesting, thanks. Out of interest, what are the records of Pink-backed Pelican in the UK - any from 2001 (poss good vagrancy year)?

      Unfortunately, I doubt the 2000 California record (with photos) from the Farallones will ever make it: http://www.wfo-cbrc.org/cbrc/photos/ although with Fork-tailed Flycatcher in Spain, I guess anything is possible!
      My Surfbirds Photo Albums

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      • #4
        I was reading the Report on the Progress of Zoology 1841,
        By Ray Society, Charles Lucian Bonaparte particularly the Bird part by Prof. Johann Andreas Wagner and he mentions a White Pelican, Pelecanus onocrotalus being shot in Prussia in 1608. Proof was by an oil painting. I love Google Books.

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