Camassia Natural Area
This 23-acre suburban patch of goodness in West Linn, Oregon, is bordered by a noisy freeway and a high school on two sides, while quiet residential neighborhoods rim the rest.
This story begins on 6 April 2022, when I visited this nature preserve to check on the bloom of the camas lily and hopefully locate a few migrating songbirds when a Cooper's Hawk flew in and began calling loudly near what looked like the start of a nest, and ends 95 days later with a handful of chicks displaying their readiness to start venturing beyond the comfort of their roost.
I visited daily at twilight during the first weeks of the nest's progress to record the reported vocal hand-off of prey by the male at dawn without success. Then, strangely enough, during the third week, I finally became acquainted with the male as it flew silently into the picture with a small sprig in its bill and offered it to the female, which she rejected.
The best part of my early morning visits was the dawn song of Hutton's Vireo, the chorus of multiple Swainson's Thrush, and Bewick's Wren fledglings nearly getting under foot.
Hutton's Vireo - usually difficult to photograph.
An opinion I base on personal experience, and the few images that accompany reports of this species compared to other commonly occurring birds in the area.
Swainson's Thrush - also camera shy.
Recently fledged Bewick's Wren - a first for me.
The combination of close views of the vireo, thrush, and wren made for a great morning as I waited in the rain for the hawks to interact.
Brooding is messy - the female preparing to accept food from her mate.
The first thing I learned about the parents' behavior sixty-eight days into my observation was how they share prey. On 12 and 14 June 2022, the male handed off to the female, who returned to the nest, ate and or rationed about half the game, then flew back to the hand-off perch and left the remains for the male in a semi-concealed location.
The second lesson learned on a short visit to the site on 16 June was about the protective nature of the male. When he arrived at one of his regular hand-off perches and began calling to the female who failed to respond, I noticed a crow and turkey vulture circling low over the nest. A few minutes later, the male chased off the potential intruders, delivered his catch to the female, and stood by while she ate and fed the chicks.
18 JUNE 2022 was the first day the female took significant time away from her brooding duties. During my two-hour visit, she was off the nest three times. The first, for 15 minutes, then six minutes, and finally 27 minutes. She also hauled away the remains of a carcass. All of this tells me the chicks have matured to the point they can maintain their body temperatures independent of the surrounding conditions.
The offspring would begin showing themselves soon.
Looking forward to the weeks ahead . . .
I attribute my third lesson about this pair of hawks to a recent online discussion about Red Crossbill being right or left-footed, without which I would not have noticed the male of this pair seemed always to carry prey in his left talon while the female brought food and fed her young from her right foot.
The fourth thing I learned about Cooper's Hawks is that nestlings' are blue-eyed in stark contrast to their parents, whose eyes are red.
My stakeout location was on a developed trail which was a blessing but also challenging because most passers-by were naturally curious and wanted to talk about what I was watching.
6 JULY 2022 marked the three-month anniversary of this project, and I was rewarded with a surprise. While the two oldest chicks actively tested their flying skills, which was great, a FIFTH CHICK, pictured on the right, emerged to steal the show by joining its siblings up on the edge of the nest. The lack of barring on the upper central portion of its breast compared to the older siblings gives it away as the youngest of the clutch!!
9 July 2022
I am calling it a day, as they say, now that all five chicks appear ready to leave the nest on a moments notice.
Fittingly for a good bye the female flew in and stayed perched 12 to 15 feet directly above me while I recorded the video below, gathered up my gear and walked out of the preserve.