June treasures

a flower show, a rare bird, and an elusive insect

June always brings lots of small nuggets of natural history to our attention—it might be a junco nest next to a busy trail but sheltered deep in a cubbyhole under an overhanging tuft of long grass, or a patch of devil’s club stems well off any human trail but with every single bud neatly removed, or terns bringing fish to their voracious chicks, or a bear, far up in a cottonwood, breaking branches to eat the maturing pods.

Here are three vignettes that I found very satisfying:

–A stroll through the meadows along Cowee Creek yielded a spectacular flower show. In mid to late June, shades of purple ruled the fields: wild iris, northern geranium, beach pea, and lupine, with touches of pink roses, yellow buttercups, and white cow parsnip. We noted more than forty species of flowers in just a few hours, without even trying to identify the sedges and grasses. A little later on, these meadows will be dominated by pink fireweed and more white cow parsnip.

–A walk in the Gustavus area surprised us with frequent sightings of twayblade orchids of two distinct species. Their tiny flowers must be pollinated by miniscule flies or something similar. Best of all was the finding of a black-backed woodpecker nest in a dead spruce. We heard two kinds of unrecognized calls coming from somewhere not far from the trail. Seeking their source, we discovered that a continuous shrill call came from a hole about six feet above our heads; a nestling or two were calling to parents for food, more food. The other call, however, was coming from a fledgling woodpecker with a yellow patch on its head and black back. Still rather frowsty and disheveled, somewhat clumsy when landing, it repeatedly announced its displeasure at our intrusion. No parents came near while we were there, and may have been away for a while, judging from the endless shrilling of the chick(s) still in the nest. Finding this nest was a minor coup, because this species is not seen very often around here.

mountain-midge-larva-armstrong
Photo by Bob Armstrong

–Another day found three friends partway up Fish Creek, in search of a mysterious little aquatic insect called the mountain midge. They are true flies but a very primitive sort. Only six species are known from North America. We’d tried to find them once before, but now was the right season. Rubbing the rocks in a stretch of fast water dislodged larval mayflies and some caddisflies and, finally, some larval mountain midges.

These larvae were very small, perhaps three to five millimeters long (there are roughly 25 millimeters to an inch), with three stubby prolegs on each side. Each proleg has a tiny suction cup ringed with miniscule hooks. The larvae creep over the rocks, holding on tightly, eating the algae and bacteria that coat the rocks.

Hatching from eggs that overwintered in cold, fast water, the larvae eat and grow for several months and then mature into tiny flying midges. The adults have no functional mouthparts, so they cannot feed, and they only live for an hour or two. That’s a pretty short time in which to find a mate and lay the eggs of the next generation. And I have to wonder just how they manage to colonize new habitats that open up, for example, when glaciers retreat. But they must have done so frequently in the course of history.

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