Conditions for Overcollecting

[Matthew Smith]

Message text written by INTERNET:cherubini at mindspring.com
>Consider that there are 640 acres per square mile. How many acres could
a single collector be reasonably expected to cover and impact in a 6-8
hour day?  Maybe 50 acres wouldbe a reasonable figure to use here. If
so, it would take 13 collectors working simultaneously to cover a single
square mile of land. 
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Possibly, but unlikely.  For this argument to work, you have to assume that
your 'resource' (buterflies) are randomly distributed across the site and
that they are static, ie the collectors are going to the butterflies. 
Experience tells me that in fact butterflies will be found (more often) in
specific parts of the search area, for example along hedgerows or woodland
rides.  Put me in a 50 acre field and I don't go backwards and forwards
like pac-man, I go to where experience and eyesight tells me the
butterflies are most likely to be.  If I was seriously intent on collecting
every individual of a particular species in a particular area on a certain
day then I think I would have a much greater impact than you suggest with
the above figures.

Regards

Matt