Sunday, August 22, 2010

Movement, Molt, and Youngsters

The past few weeks have taken us from mid-summer into the beginning of Fall. Changes abound, and I've been able to capture some of it with my snazzy new camera and lens.

Many migratory species have begun moving south recently. One of the most conspicuous in the yard has been the Black-headed Grosbeak. The male shown above was particularly interesting (to me), as it's the first molting individual that I had ever seen. (They always seem to lay low in mid-molt.) Judging from the head plumage, this individual appears to be a second-year male. This male was around for one day at the end of July and was never seen again. Since then, at least one female has visited on three or four occasions.

More migratory species graced us with their presence earlier in the month. But, of course, this was when I was in between cameras, so I didn't have the opportunity to get photos! Anyway, these transients included an Orange-crowned Warbler and a Western Wood-Pewee. Neither has been observed here since. In addition, a couple of Cedar Waxwings were feeding in the neighbor's apple tree the very afternoon after that shipped off my old camera. This kind of sucked, as I had several nice sun-lit shots against a blue sky. But waxwings are year-round residents, abundant in our neighborhood, and tend to hang out in flocks in that apple tree in the winter. I'm sure that I'll get another shot.

A hatch-year Rufous Hummingbird enjoys our sugar-water feeder.

A slightly overexposed female Anna's Hummingbird enjoys our sugar-water feeder, after fending off multiple Rufous.

Male Rufous Hummingbirds are the deadbeats of the hummer world. They show up here in late February/early March, mate with the females that follow close behind, and then take off after the kids are born. No child support or anything. So that leaves mom and the kids to fend for themselves, and that's exactly what they've been doing here. There have been at least three individual Rufous and at least two Anna's going at it since the beginning of the month. Despite the fact that I have a window feeder on the opposite side of the house, the hummers all tend to "share" the more prominent feeder in the backyard. And when I say share, I mean fight tooth-and-nail. They spend so much energy fighting each other that they pretty much have to suck massive amounts of sugar-water afterwards. Seems like sharing perch space would be a more efficient use of energy, but what do I know. Anyway, it's been both interesting and entertaining. And I will be sad to see the Rufous take off for good next month.

A juvenile male Anna's Hummer (note the partially-colored gorget)

A female Black-headed Grosbeak stops by the nyjer feeder... before realizing that she doesn't like nyjer.

This hatch-year Spotted Towhee stopped by the yard in late July, never to be seen again.

American Goldfinches were still rockin' the breeding plumage up until recently...

... but now the majority of them are all molty and nasty-looking. The seasons are definitely changing.

Late summer molt is exemplified well by American Goldfinches, particularly by the males. As shown above, males lose their brilliant yellow plumage and black cap. Females undergo a less dramatic change, transforming from light yellow/green to more of a light yellow/bronze color. Molt begins in late July and is complete in most individuals by mid-September. American Goldfinches also flock like crazy out here in September and October (50-100 visitors at a time is typical for us). We've already witnessed a sharp increase over the past few weeks, and are now hosting up to 18 at a time. This number will likely triple in a few weeks. I will definitely be purchasing a lot of seed over the next two months. To help with the anticipated demand, I've already put up a second nyjer feeder (left).

Starlings are also beginning to molt into their "speckled" winter plumage, while losing the yellow coloring of their summer bills. This transition is more subtle than that experienced by male goldfinches but, as shown below, juvenile starlings can look rather odd at this time of the year.

This hatch-year European Starling certainly caught my eye. I thought it was a juvenile Flicker at first!

Hatch-year male House Finches slowly molt into their reddish-pink plumage at this time of the year.

A Western Scrub-Jay enjoys a drink on a hot summer afternoon. Water is very important in regions with warm, arid summers.

A Black-capped Chickadee stops in for a peanut on a late August afternoon.

That's about it for now. I'll have another update (and more photos) in a few weeks. And then I'll be getting very busy with work. (Though I'm sure that I'll be able to tear myself away to photograph migrants in October!)

No comments: