Butterflies are such blatant sun-lovers. Give them warm summer conditions and you see them flitting along roadside ditches and wet pastures everywhere. Lower the temperature 10 degrees and cover the sky with dark clouds and you don’t see a single one.

Never was this heat-seeking preference of everyone’s favourite insects so obvious as on the two latest butterfly counts in southern Ontario.

Projected high for the day on the Sunderland Count, covering a 24-kilometre-diameter circle just north of Uxbridge, was 34 degrees, with sweltering, hazy, humid conditions spawning thunderstorms.

After showers cleared off in the morning, volunteers combing the sedge-rich north slope of the Oak Ridges Moraine found and identified an amazing 60 species of butterflies. It not only broke the record for this always-productive tally, it set a new high for all counts in Ontario of butterflies seen in a single day.

The compiler, James Kamstra, found a brand-new butterfly for the area -- a black dash, a small orange-and-black skipper common in the U.S. Midwest.

Pumped with excitement, many of the tired and sweat-soaked volunteers set their sights on the Minden Count the following weekend, where a rich mosaic of  bogs, marshes and wet meadows often produce an interesting blend of southern and northern species. Scouting parties during the week turned up a promising variety of hairstreaks, skippers, ladies and fritillaries.

Enter Mother Nature.

A major cold front moved in around dawn the Saturday of the count, with a predicted high of only 18 degrees. Hearing the forecast, half the volunteers made the wise decision to stay home. The handful who showed up quit counting at noon, when a long, soaking rain closed in over Haliburton County.

Tally total: a surprising 27 species, given that the sun didn’t break through the clouds more than once or twice, leaving thousands of butterflies hiding out in the vegetation. Average total for this count would be in the mid-fifties. Average individuals for each species seen that day was one or two, instead of dozens.

It’s significant that two bog coppers were found despite the dismal weather. Most butterflies have very definite habitat preferences and host plants where they lay their eggs. As housing estates and cottages blanket southern Ontario, it’s vital that all wetlands be protected, and especially bogs, the only place on the planet where bog coppers and bog fritillaries dwell.

Nature queries: mcarney@interlinks.net or 905-725-2116.

Durham resident Margaret Carney, in addition to writing nature-appreciation columns, has also published several children’s books.