Glassberg is quite correct.

[Kenelm Philip]

> There is of course the well-known example where a documented extinction
> did occur, the British day-flying moth the New Forest Burnet, Zygaena
> viciae ytenensis.

In that regard, I found the following comment of interest, quoted from _The
Aurelian Legacy_, by Michael A. Salmon, Un. Cal. Press, 2000):

"R. F. Bretherton considered that over-collecting was a decisive factor in
extermination of the last English colony of the New Forest Burnet (_Zygaena
viciae_), but even in that case it was probably no more than a contribut-
ory one. The overgrown state of its former habitat today suggests that it
could not have survived."

The final sentence is referenced to:

Tremewan, W. G. (1966). The history of _Zygaena viciae anglica_ Reiss
(Lep., Zygaenidae) in the New Forest. _Entomologist's Gaz._ 17:187-211.

Presumably Neil has access to that article, and can explain how Salmon may
have misinterpreted it?  :-)

	On a more serious note, Neil's description of the sheer amount of
hard work it took a _number_ of collectors to wipe out that colony, and
the fact that this is the only example of extinction by over-collecting he
mentions, indicates that collecting by scientific or hobby collectors is
really not much of a problem, if any. The only case of destruction of a
butterfly colony I know of in the Fairbanks (Alaska) area involved a bull-
dozer, despite my own long-term collecting at various local sites.

	In 1991 I visited Keno Hill (Yukon Territory)--a site where there
was considerable local concern about the effects of foreign collectors on
the butterfly fauna of a small patch of alpine tundra on the hilltop
(6000 feet). Although a number of people elsewhere in the Yukon had told
me that all collecting on Keno Hill was now outlawed "to save the rare
arctic butterflies there", I found that the local concern was directed
solely at commercial collectors. I and my colleagues were welcomed (even
to the point of being invited to the Canada Day free feed at a local
eatery). It turns out that all the hilltop species were widely distributed
in the Yukon and Alaska, and were in fact still doing fine on Keno Hill
despite some exceedingly heavy commercial collecting (for _Parnassius
eversmanni_) in the past (which the Keno City people were not aware had
happened. They were concerned with more recent visits by people who may
not have been collecting commercially, but were clearly attempting to
escape being noticed by the locals). And collecting is _not_ outlawed
at Keno Hill.

	To re-work an old proverb: Take care of the habitat, and the butter-
flies will take care of themselves.

	I suspect that one reason that collecting gets blamed so often (by
some people) for damage to butterfly populations is purely political, as
follows: people always want to be seen as doing _something_ about perceived
problems. Land developers are wealthy, and their projects produce tax
revenue and employment, while butterfly collectors are few, and have no
political clout. Guess which group will get blamed publicly for any decline
in butterfly numbers, and will be the target of regulations? (I'm not get-
ting after Neil here--he's clearly aware of what developers do!)

							Ken Philip
fnkwp at uaf.edu




 
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