I need help.......
Kenelm Philip
fnkwp at aurora.alaska.edu
Thu May 4 16:02:29 EDT 2000
> Can you present us with a math based model that describes the assumptions
> that would have to be made for this type of harm to realized?
There is one type of 'harm' that does not need a mathematical
model, other than some very general statements. What happens when a widely
dispersing species is being raised and released in an area at or near its
extreme limit of dispersion--when a biological survey is being carried out
in that same area? There is a significant chance of false positives for
the occurrence of that species--since the number released may be larger
(even _much_ larger) than the number that would disperse naturally to the
region.
For a specific case, consider the Painted Lady in Interior Alaska.
This species is known to reach Alaska occasionally--I have a small series
of very worn specimens from the north shore of the Kenai Peninsula--but
there were no records from Interior Alaska until 1986, when I obtained a
(suspiciously) fresh specimen from the summit of Ester Dome, near Fairbanks.
It is not impossible that this was a natural occurrence--but at about the
same time I became aware that Painted Ladies were being raised by a number
of classes in Fairbanks elementary schools--and in all cases the adults
were then released outdoors in late spring. Ester Dome is a known site
for hiltopping in the Fairbanks area, and thus can act to concentrate
species that are very thin on the ground. I would guess (and I admit it's
only a guess) that it is far more probable that this specimen was raised
and released in Fairbanks than that it flew here under its own power.
At any rate, the specimen cannot be used to prove natural dispersal to
Interior Alaska--and nor can subsequent specimens unless the numbers are
very large (which is unlikely).
Oh well, at least the schools aren't releasing Monarchs. At this
time, there is no record of a Monarch from Alaska. Many people in both
Alaska and the Yukon claim to have seen Monarchs--there is even a 'Monarch
Road' in Fairbanks--but upon questioning they all turn out to have seen
(Canadian) Tiger Swallowtails. But it's presumably only a matter of time
before a locally-released Monarch is captured somewhere in Alaska...
Ken Philip
fnkwp at uaf.edu
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