numbers game or counting

[Kenelm Philip]

	Back in the late 60s I got interested in temporal dissociation
in the genus _Boloria_ (s.l.) in Interior Alaska. For 4 successive summers
I made repeated trips to a local spruce bog which (conveniently) had a
network of old cat trails through it--and supported six species of
_Boloria_. I laid out a standard transect along the cat trails, which
took about an hour to traverse. By this time I had learned the six species
well enough that I could ID them at a distance in most cases.

	Every clear day during the summer (unless I was up at Eagle
Summit or some other such site) I made a midday swing through the bog
and recorded the number of each species seen, which was also the number
seen per hour. This was not a very lush habitat--the counts ranged from
zero to 25 per hour. Plotted as histograms, each of the more abundant
species tended to have a triangular plot over its flight period (except
for '_titania_', which had a long end-of-season flight and a more
trapezoidal plot), which gave me some confidence that the data were
reliable.

	It was these counts that gave me confidence that _B. chariclea_
and _B. 'titania_' were behaving as two different taxa in Interior Alaska,
with quite different flight periods in the bogs, in addition to the odd-
numbered year flight of _chariclea_ and the every-year flight of
'_titania_'.

	But I also concluded that repeated counts by the same person over
the same transect produced meaningful data, provided the person tried to
use the same procedure each time. I also feel that this sort of count is
far more useful than a one-day-per-summer count involving numerous people
and a number of sites.

							Ken Philip




 
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