'Counting' butterflies

[Kenelm Philip]

	I'm not a great fan of the 4th of July butterfly 'counts' either--
but there are occasions where some rather simple-minded counting activities
can be useful.

	Back in the late 60s/early 70s I was wondering about so-called
temporal dissociation in _Boloria_ in Alaska. I ran a transect in Gold-
stream valley near Fairbanks, in which I walked about 2 miles (a mile
each way) along an old trail through a mixed spruce forest/bog habitat.
For all _Boloria_ seen (which I could identify at sight after a bit of
practice) I would list the number of each species seen per hour. Since I
was moving all the time, I doubt there was much bias introduced from
multiple counts of the same individual. I never saw any evidence that
clouds of _Boloria_ were following me through the valley--not that I'd
mind if they did during collecting.  :-)

	Clearly there would be some duplication on the outward and return
legs--but that was no matter, since I treated each leg as a separate
observation and averaged them.

	The results provided nice (if only preliminary) evidence for a
fair degree of temporal dissociation within _Boloria_ (or _Clossiana_).
Each species individually produced a triangular or trapezoidal curve of
#/hr vs. time. The peak numbers reached 20 to 25 per hour--so this was
not a really lush spot. But looking at the plots, it was hard to dis-
miss them as mere artifacts of counting errors...

							Ken Philip
fnkwp at uaf.edu





 
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