Evidence: The ivory-billed woodpecker population in south-central Florida
was extirpated single-handedly by a museum collector (see James Tanner's
1942 report--we're talking several dozen birds here, at the time a very
respectable percentage of the entire world's population of this very
specialized bird), the California Condor was depleted perhaps beyond
recovery by egg collectors working for museums and for private individuals
(egg-collecting was big at the turn of the century), the Eskimo Curlew was
extirpated entirely by market hunting (=collecting for the trade), the
Mexican grizzly bear was exterminated during the 1950's by a single
rancher who declared war on the bears after one killed a cow, the desert
slender salamander was almost wiped out by private collectors (imagine,
collecting an animal out of existence that you can't even maintain in
captivity, and the specimens don't even go to museums), etc. etc. But
it's also true that habitat destruction is the biggie. Unfortunately it's
even more true that the interaction of multiple factors is the real
culprit behind the status of most endangered forms, and behind the
extermination of most others. "Multiple factors" definitely includes
uncontrolled collecting. The likelihood that collectors take a smaller
number than do bulldozers does not excuse them from their share of the
responsibility, and collecting at the wrong time in a population's history
or life cycle could easily be the straw that mixes the metaphoric camel of
a different color. That is, collecting by itself under some circumstances
could easily exterminate a population, and therefore might exterminate a
species. This is not a matter of speculation--it has happened, and
unfortunately is increasingly likely to happen as habitats shrink.
Collecting is at its potentially most damaging when money changes hands,
and that's what CITES is designed to control... ...unfortunately, cultured
or captive-bred plants and animals are usually undifferentiable from
collected specimens as to source, and a collected specimen is just as
collected whether money changed hands or not. Hence the need for
documentation of CITES specimens regardless of origin.
And to get a little fact in here--it's true that the passenger pigeon was
depleted in large measure by unrestricted hunting, but the destruction of
the midwest beech forests, which were the primary breeding habitat of the
species, is at least as much to blame for the final extinction. More
fact: the sailors killed dodos by the peck, if not the bushel, but the
introduced dogs, pigs, and rats did their share as well. Deforestation of
Mauritius and Reunion islands also helped. Great auks might have been able
to withstand the relentless harvest had it been confined to the birds
themselves, but the gatherers (=collectors) took every egg they could get
as well, so they screwed up the bird's life cycle. Guaranteed extinction.
Multiple factors. Coming at you from all sides.
Sean Barry
...it's good to back in the fray again...