Butterflies and weather

[Stanley A. Gorodenski]

> "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."
> 
> ------------------------------------------------------------------
> 
> This seems right on the mark.  

With respect to the last sentence,  I disagree.  One might look at local
species, or one widespread species like the painted lady and be tempted
to apply the usual population dynamic considerations, such as
predator/parasite-pray interactions, but I think when you look at the
whole picture, i.e., a lot of other of species and the whole U.S.
including other countries, global warming is the more probable
explanation for what we have been seeing this year.  And why should be
object?  If global warming is resulting in more and earlier lepidopteran
species, then this could be viewed one good side effect of it.

Stan

 
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