The orange sulphur butterfly had a banner year in 2002. I counted nearly 200 in a field the size of 1/2 a basketball court!  2003, 2004, and now 2005 do not look to be good for these beautiful creatures. It's now July first and I've only seen a very few.

Footnote: June 2011 - the sulphurs have never reappeared in anywhere near the numbers of 2002. Indeed, most butterflies seem to be less numerous than that great year. I'm convinced the number of butterflies are decreasing year over year, at least here in my tiny corner of the world - northern Illinois. Of course, the Prairie State is now mostly covered by the twin monocultures of soybeans and corn, and has been for the last 100 years or so. Neither ecosystem is conducive to the survival of any flora or fauna except the one it is intended for, and our insects are suffering as much as other organisms. The only species that benefits from any of this is Homo sapiens.