Butterflies and weather

[Ron Gatrelle]

Today's weather has very little to do with most of the butterflies we see
today. The numbers being seen are because of yesterdays weather - actually
last years (seasons). The cold winter and conducive conditions for egg and
pupal survival. Before that conducive conditions for larval survival. Don't
be surprised if the explosion in this years Vanessa species results in
larval overcrowding, insufficient host availability for the size of the
demand, increased disease and predation which would result in a bust year
next season and the next and next. There will be more parasitic wasps and
flies now that will have the upper hand in the food chain for a few years.
Then the cycle will begin over again.

What I am saying is that we notice adults and their population
fluctuations. We do not see the immatures and their fluctuations. We start
with many many times the number eggs than larvae and many many times the
number of larvae than pupae and adults.
So if there is a big drop next year don't blame it on spraying, over
collecting, etc. "blame" (attribute) it to an unhealthy out of balance
population explosion the season before - and see it as nature simply
bringing populations back to normal levels.
Ron


 
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