Crested Caracaras — A Family Portrait, Part IV — How They Grew

on original post here /may enlarge any image by clicking on it. Click again for a detailed view.

In less than two months the two infant Caracaras progressed from bits of fluff about the size of table tennis balls to fully fledged birds weighing about a kilogram.

Their rate of growth was so rapid that their appearance seemed to change visibly from one day to the next.

Today, I’m posting a series of six images that I made of the youngsters — a sample of dozens of portraits that I made of them — covering a timeline of just over a month. Not to repeat a cliché, but in this case the images say more about the young Caracaras’ development than my commentary possibly could.

I made this first image on May 8, 2021, and I estimate that the nestling in the image would have been about three weeks old at the time. It had not begun moving around the nest, and it was still covered with fluffy “chick down.” At this point of its development it was helpless and utterly dependent on its parents for food and protection.

One week later, on May 15, and the youngsters have started to interact. They’ve shed much of their chick down and have started to grow in juvenile plumage. You may notice that these young Caracaras are colored differently than the adults. The young birds will only gradually lose their brown and taffy color scheme as they mature and will not display fully adult plumage until they are about three years old. Notice that on the young birds the bare facial skin is pink whereas on the adults it is yellow-orange.

May 22, and the young Caracaras have begun to stand and walk. They’re now about half the size of adult birds and their proportions are beginning to assume those of adults. They’ve almost entirely shed their chick down. The youngster on the left side of the image has a noticeable pinkish bulge on its upper breast. That bulge is the bird’s “crop,” which is a kind of fore stomach in which the bird stores undigested food. It is not visible when empty, but swells considerably when it is full.

As of May 31, the youngsters are almost adult-size and have attained the proportions of adult birds. It’s now just a question of growing in flight feathers and strengthening their wing muscles, and these birds will be able to fly.

It’s now June 6, and flight training has begun. The young Caracaras are now fully fledged, although their flight feathers still need to fill in a bit. They are adult-size birds. They are very restless and are taking short flights from their nest to the arms of the nest Saguaro.

June 7, and this is one of my final images of the now almost-fledged young birds. They were now flying back and forth to the nest cactus’ arms and practicing their landings. Their flight feathers had completely filled in.

I returned for a final session with these birds a couple of days later and the nest was empty. They had successfully fledged and now faced the dangerous and exciting process of learning how to fend for themselves. Adult Caracaras stay with their young for up to three months after they fledge, so it will be September before the juveniles are finally on their own.

Tomorrow, I’ll post about how and what the parents fed their offspring.

Images made with a Canon R5, Canon RF 100-500mm f4.5-7.1 IS L zoom lens+Canon RF 1.4x telextender, M setting (auto ISO), settings varied.

Related

Crested Caracaras — A Family Portrait, Part II — The “Mexican Eagle”June 15, 2021

Crested Caracaras — A Family Portrait, Part IJune 14, 2021With 1 comment

Crested Caracara — Return Of A FreebooterNovember 6, 2019With 2 comments

One Reply to “Crested Caracaras — A Family Portrait, Part IV — How They Grew”

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