28.01.02
Solving
the riddle of the plague of frogs
A
natural history 'whodunnit' comes closer to being solved today (29
January) when 大象传媒 Wildlife Magazine names the culprit most likely
to be to blame for the deaths of millions of frogs in UK gardens over
the past ten years.
Householders
in the South East first sparked the investigation when they began
making distressed calls to zoos and wildlife agencies after finding
dead and dying frogs, with open sores and bloody stumps instead
of limbs.
The public's
initial concern, and subsequent co-operation, eventually led to
the mobilisation of what is believed to be the world's most extensive
investigation into a wildlife disease, with over 62,000 frog corpses
being studied.
In its report
on the study, 大象传媒 Wildlife Magazine names the chief suspect in the
case of the plague as an iridovirus most closely related to one
found in American bullfrogs.
How the virus
infected UK garden frogs is still being explored, but one theory
is that a change in the source of goldfish imports may be to blame.
Prior to the
early 1980s, most goldfish reaching Britain came from Milan but
thereafter fifty percent derived from heavily subsidised farms on
Israeli kibbutzs with the rest provided by the USA.
In the US, bullfrogs
breed wild alongside commercially nurtured goldfish and are often
blasted with shotguns to stop them competing for food pellets.
Tom Langton,
author of the magazine's article and a member of the study team,
explains: "Bits of bullfrog could be eaten by a goldfish that
is netted and flown off for quick distribution to British garden
centres."
He says the
evidence is compelling but adds "It's a complex situation and
the exact causes are still not known. Slug pellets, vehicle emissions
and changing weather patterns may play a role in reducing frogs'
resistance to the virus; the isolation of urban frogs and in-breeding
could also be a factor. More research is needed urgently."
Tom Langton
says the only sure lesson is power of bacteria, viruses and other
pathogens to shape nature. "It is not just the mighty predators
that dominate and structure communities. The microbe has as much
bite as the biggest canine - and almost certainly always will have."
Notes to
editors
Tom Langton runs the frog conservation organisation, Froglife. The
charity can be contacted on 01986 873 733. Further information on
the survey, and on the IUCN's Declining Amphibians Population Task
Force may be accessed via the charity's website: www.froglife.org
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