Sunday, September 18, 2016

Time flies like an arrow, crane flies like a wall

It's September, and no matter what your age, it's a time of change.  The nights have gotten chillier, morning breaths condense, and giant mosquitoes are now flying in open windows at night.  But no, they're actually not mosquitoes, but a species of non-biting species of fly called the crane fly.

Started noticing them hanging out on the wall by the school.  A mysterious ratio of 20 males to one female.

The way they perch on the wall is a bit unique.  Their heads are flush against the wall, the rest of the body hanging by the front four legs, and the rear legs keeping their abdomen pointed up.

The crane fly has only one pair of flying wings.  Most other flying insects would have two pairs.  If you look closely, you'll see a pair of club-like appendages that evolutionarily were the second pair of wings.  These halteres act as counterbalances for the crane fly, a feature that most other types of flies have.

What we see as the crane fly is actually a short-lived part of its life cycle.  The adult form lives for only a few weeks, doesn't eat, and it's sole purpose at that stage is to mate.  They mature around the same time of year to maximize their opportunity to mate.  Spiders take advantage of the bonanza of crane flies, whose gangly legs snag easily on webs.

Eggs are laid in damp soil, and the grubs feed on grass roots.  In large enough populations, they can devastate lawns.  Those of you who garden may have come across them as fat, grey caterpillar-like grubs.

Female insects that lay their eggs beneath the ground will have an ovipositor, or a tapered end of the abdomen.  Grasshoppers are another insect with this feature.

Males are typically smaller, and have a blunt end of their abdomen.

They seem to manage to be able to fly while copulated, though I have yet to get a good look at who steers.  I can't imagine it to be a romantic experience.

Sunday, May 1, 2016

I'm usually the one on dog duty in the morning.  My walking route takes me around a nearby elementary school.  And at least once a year, I've spotted one or two killdeer (I usually hear them before I see them) strolling through the schoolyard on a spring morning.  I used to think that they somehow had gotten lost - they *are* shorebirds, after all - but according to

"Look for Killdeer on open ground with low vegetation (or no vegetation at all), including lawns, golf courses, driveways, parking lots, and gravel-covered roofs, as well as pastures, fields, sandbars and mudflats. This species is one of the least water-associated of all shorebirds."

When I was elementary school age, I had learned from a nature documentary that the killdeer would famously hobble around with what seemed to be a broken wing as a way to distract predators from a clutch of eggs at the nest site.  The killdeer then become a minor character in a story I wrote for Language Arts, a story that became a source of pride when my grade 7 teacher said some encouraging words regarding the maturity of the piece in front of the entire class.  That was probably why I still write about birds today.  Maybe there's a child at this school who has also seen this bird and has written it into a story of his or her own.

Friday, January 1, 2016

HNY 2016

We got to Boundary Bay just in time to catch the sun rise this morning at 8am. While not as cold as last year, it was still below freezing. Bird activity was minimal compared with last year, with a few low flyby's by hawks from behind so that our only photos were tail shots.
Cooper's hawk

Northern flicker.  A common woodpecker in residential areas of the city.

Saw-whet owl
Owls are always the highlight for me, and we would've missed this one down in the thickets if not for some experienced birders lying prostrate aiming their big lenses at this little thing.