Although it’s probably the first moth of the year that I look forward to most as far as signs of spring go, it’s definitely the return of the first avian migrants that marks the arrival of the season for me. In particular, Red-winged Blackbirds. Where I grew up there was a small swampy wetland area at one corner of the property, and every spring the song of the Red-winged Blackbirds would ring out from that swamp just as the snow started getting mushy and the ground muddy. They’d show up at the seed scattered below the feeders, and would perch in the tree branches above the house. Even before I started paying attention to birds, their return was a sure sign of spring. The sound of a Red-wing singing immediately recalls memories of my childhood to my mind.
The same warm front that enticed the first moth out of hiding last Wednesday brought with it the first Red-winged Blackbirds. They’d shown up at my mom’s, an hour or so south of us, last weekend so I knew it was just a matter of days before they arrived here. Red-wings, like all blackbirds, are diurnal migrants. They roost, often in large flocks (especially in the fall), overnight and then move during the first half of the day. They put down by the afternoon so they have some time to forage before going to rest at night again. When I went out for my afternoon walk with the dogs on Wednesday, and all during it, I watched for Red-wings without seeing any. It was only upon returning to the house that I heard the distinctive chuck of a Red-wing in the trees by the feeders (the photo above is a record shot of that bird). Spring has officially arrived.
The next day, Thursday, we got our first grackle. I have no similar associations of grackles with spring, other than that they’re usually on the tail of the Red-wings (who nearly always arrive first by a few days). Just the one so far, that I’ve noticed. On Saturday, Dan spotted a pair of Pine Siskins at our feeder, and today, a Purple Finch. Dan said he’s seen siskins around all winter, in low numbers, but they must hunker down by the time I’m out for my walk with the dogs in the afternoon; I haven’t seen one since December. Ditto on the Purple Finch.
All of these birds are temperate migrants, moving a short distance south of their breeding range to slightly milder regions – though not necessarily a whole lot milder, as some blackbirds and grackles do spend the winter in Ontario, along the shores of the lower Great Lakes. The siskins and finches winter around here, but many travel farther south, beyond our border; their movements aren’t really migrations proper as they’re more food dependent and vary from year to year, but they often follow similar timing when they happen. The individuals we saw this weekend may represent some of these returning, rather than locals, though we can’t really tell.
As far as the two blackbird species, the timing of their return tends to be with the first warm fronts that bring spring-like temperatures to a region. They can get by on seed, but they’re also insect-eaters when there’s insects to be had. If you see Red-winged Blackbirds sticking their bills into cattail heads, for instance, they’re actually looking for small moth caterpillars that spend the winter there, rather than gathering fluff or eating the seeds.
I don’t have a photo of the first Red-wing from last year, but the first grackle seems to have showed up on March 21 (or at least, I have seven photos of a grackle from that day, and I pretty much never photograph grackles except the first one to arrive because it’s so exciting). So it might be he’s a little ahead of schedule. The date I have in my head for the arrival of Red-wings is March 15. This is carried over from my home where I grew up, too, which is more southern than where I live now. I don’t really have any data to back this notion up, but it does seem to me that the blackbirds being back already is earlier than normal. That first one last week was on March 7.
There is some concern about climate change causing the timing and pattern of bird migration to shift. Many birds use temperature cues rather than day length to know when to migrate. Before humans arrived on the scene, birds and the food they depend on had evolved together so that everybody’s life cycles were all carefully timed. Birds would arrive back from migration timed just right to be able to set up territories, build nests and incubate eggs so that the insect population that they depend on to feed their nestlings peaked just as the eggs started hatching. Early nesters who come back too soon because they’ve been fooled by abnormal weather patterns risk their own survival (should the weather turn foul again – this is especially dire for birds like swallows that catch their food on the wing) and/or that of their nestlings (if there’s not enough food available yet when they hatch).
My mom posted about this and talks about it in a little more detail. She also includes a link to a CBC radio broadcast on the topic, which happens to interview some Canadian birders and biologists I know personally. Worth a listen if you’re interested.