Name that bird
VulcanSpirit
Richard & Alison Brunstrom
Sun 26 Jun 2011 02:30
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Easy, I expect you're saying, it's a Herring Gull.
Well yes, but it's not quite that simple. I photographed this one in
Newport and it is basically the same species that occurs in the UK.
 But gull taxonomy is actually very complicated and
identifying gulls in the wild challenges even the experts. In the UK we
distinguish the Herring Gull as a separate species from its close relative the
Lesser Black-backed Gull but it's far from clear that this distinction is
justified. An over-simplified definition of a species of animal is that it does
not interbreed with other species - cats are cats and dogs are dogs. But gulls
do not comply. Herring Gulls are known to regularly and
successfully interbreed with Lesser Black-backed, Glaucous, Glaucous-winged
and Greater Black-backed Gulls. Indeed gulls form a ring of interbreeding
species around the whole northern hemisphere - and it's only in the UK
that Herring and Lesser Black-backed Gulls are sufficiently distinct
to be separated as different species. There remains a deal of uncertainty over
how to classify these gulls as they just do not conform to the usual definition
of a species. I think I'll stick to reptiles and
amphibians.
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