Posts have been a bit sparse this month and short when they do appear because I’m preparing to defend my Master’s thesis. I am, however, still working at the ponds every day, so here is a little update.
This summer, despite being one of the hottest on record in the rest of Canada, has been cool and wet here on the west coast. While I find this annoying in some ways, it’s useful from a science standpoint because it’s extending the stickleback breeding season—the shallow water where my enclosures are set up doesn’t get so hot that the fish die. Thus my experiment is continuing for a few more weeks.
The sides of my enclosures are speckled with insect exuviae—mostly damselflies, but increasing numbers of dragonflies, especially the big Aeshna multicolor, as well. The killdeer have hatched another batch of chicks and recently a mother duck showed up with ducklings. (They seem to have left; probably because the plastic sides of the ponds make it very difficult for the ducklings to get out of the water.) There are still tadpoles of all sizes, and the largest of them are now full-grown frogs.
The Scotch broom and many of the native wildflowers are done flowering. Now, some white sweet clover—another invasive legume—is dominating the landscape. I’m not going to be trying to remove it: it can grow back from cuttings, and I don’t really have the time.
Inside the enclosures, especially those with other vegetation, filamentous green algae has been growing rapidly. The stickleback are good at keeping the areas around their nests clear, but it was threatening to cover some enclosures, so I’ve spent a lot of time scooping it out. Fortunately, I seem to have an ally in some chironomid (non-biting midge) larvae. They are tiny little bloodworm-like things, except green rather than red (actually, I think they’re transparent, and the green is the algae in their guts), that encase themselves in a layer of slime and graze on the algae. They’ve managed to control the algal bloom in several enclosures.
My favourite moment this week has been the appearance of fledgling barn swallows. The picture above shows two of them perched on the ropes that hold up my enclosures. There were three at one point, all huddled together, while one of their parents wheeled around a chirped at them. One by one, they all eventually took flight.