Coopers Hawk (accipiter cooperri)

Hawks, Condors, Goshawks

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ostrich
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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sat Jul 20, 2019 7:33 am

07/18: I have again observed some proning behavior now from the hawklets, mainly it seems from the smaller (and likely male) individual. The larger female although off nest tree frequently now, still seems to be using the nest itself or the branches very close to the nest as a resting area. Over the past several days I have seen the adults using the nest to do food drops and allow the fledglings to self-feed. In one case interestingly the hawklet was proning in a crotch in the SE tree from the nest, this is a spot where there are a few sticks laid in the crotch, which may have been from nest building early in the system. In the latter case the hawklet was in a tree close to the NE corner of the park border and also near to the surrounding backyards. So this is a progression a little farther from the nest tree.

https://www.youtube.com/watch?v=E1O3kWMV-go

07/19: At approx 8am, after walking around the park and not spotting anyone, I found one fledgling in the roost tree N of the nest, this time I think the female. After a short flight it landed on top of the roof of a house immediately N of the nest and the roost tree. It hopped/walked along the roof several times, and subsequently flew a bit farther N to some of the further trees/houses.

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Later in the day approx 15:15 there was an interesting sequence, one of the adults (I suspect the male, but I was not positive) was already roosting beside the nest tree with food. It was waiting for a few minutes without any obvious reaction from fledglings who were not in sight in the nest tree or immediately nearby. The adult then flew to the east and low along the line of bushes that border the house that forms the border of the park S of the nest tree, where there are also some dense foliage and trees. There were some vocalizations from at least one fledgling immediately, somewhere in those trees. However after a minute or two the male flew back from the same area and back to a low branch in the nest tree, still with the food. The adult was followed by one fledgling but it did not land at the adult or take the food, it landed in branches nearby but stayed there. After another couple of minutes the adult flew back to the original tree, paused there again, and finally flew back around the bushes to the area SE. At this point there were very loud vocalizations from the other fledgling probably meaning it was able to obtain the food. However I was unable to spot exactly who and where they ended up with the food.

This appeared to most likely be the adult trying to entice the fledglings to come directly to a location to get food from an adult, in contrast to doing food drops in a static location like the nest.

https://www.youtube.com/watch?v=msPnJ3HpQGI

ostrich
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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sun Jul 28, 2019 7:11 pm

07/20: One of the fledglings was quite close in the lower branches of the nest tree.

https://www.youtube.com/watch?v=aiPhZnadvXo

07/21: This time the larger female fledgling was down in the lower part of the nest tree and resting.

https://www.youtube.com/watch?v=mP3sqJpkLiA

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07/22: At ~13:30, both fledglings were right near the entrance to the park across from the nest tree. After a couple of minutes an adult (likely the male) came in from the direction of the nest tree and dropped off a food item on one of the branches, which one of the hawklets immediately hopped over to try to grab. For about a minute or so the first hawklet looked at the food but did not appear to try to eat much of it. Then it seemed to lose interest and move away, at which point the smaller male hawklet moved in and took possession of the food.

The second hawklet did spent a couple of minutes consuming some of the large food item, but it too stopped eating and left it while there was still a substantial amount left. A piece that fell on the ground looked quite old and dried without much visible blood, which perhaps suggests it could have been an older cached food that had been retrieved by the adult. If that is the case, the young did not seem overly interested in it.

https://www.youtube.com/watch?v=RtwRdN54Hig


ostrich
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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Fri Aug 02, 2019 9:08 pm

07/24: Fledgling hiding in the tree branches along the NW border of the park.

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I observed an interesting sequence, starting with the male in the lower part of the nest tree around 19:15, after several minutes he suddenly reacted to something he spotted, and the adult female came flying right into where he was perched and rather aggressively flushed him from his perch making loud whaa calls, but the male did not have any food. Immediately subsequent to this, he flushed from his new perch right on the tail of a songbird he initiated a pursuit of. When I walked over to where he had gone in the adjacent trees, he apparently made a capture although I did not see the actual catch. However he did have a prey item and was consuming it.

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07/26: At around 9:50 I was fortunate enough to catch both fledglings together in the stand of trees and bushes in the middle of the park that has been a favorite spot in previous years. Both juveniles perched right beside each other, allowing for a decent comparison shot. The apparent larger size on the one on the left strengthens my feeling that she is female and the other male.

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07/29: 12:30, I was able to get some good shots of the adult male in the central treed area although the fledglings did not seem to be around at the time.

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08/02: I observed at least one fledgling outside the border of the park for the first time today, as I was walking out of the N entry to the park along the adjacent N-S street, suddenly one Coopers went past me flying north up the street, followed by one of the fledglings which was whistling intensely and then landed in a tree about 20 yards north of the park border. I could not tell whether it was the other juvenile or a parent that it was chasing, but I suspect a parent considering how loudly it was food begging.

In the evening around 20:15 I found both fledglings in a tree along the path down from the nest tree, and both were making periodic jumps and flaps to different spots in the adjacent trees, with a lot of alarm calls coming from nearby passerines. One of them flew without my seeing them, but the other flew to the very NW corner, where I caught a brief sight of it stooping aggressively and chasing a cottontail rabbit, which it did not capture. However the fledglings seem to be acquiring more aggression and are making attempts to hunt on their own.

ostrich
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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Wed Aug 14, 2019 9:14 am

There has been progressively greater activity of the fledglings both in and out of the park, with the fledglings spending more and more time both further from the nest in the corners of the park, and sighted on the streets adjacent (about 100-150m N of the border of the park).

Aug 3: In the morning (at 08:00) both fledglings were moving around quite a bit from the NE corner of the park around to the NW side, one landed in a backyard immediately beside the N entrance to the park.

Fledgling showing nictitating membrane:

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Later in the day around 6pm I was fortunate enough to find the adult male in the central tree in the park, and got a good look at the left eye. This showed the same unusual dark blotch that I had observed last season, so this should be good confirmation now that both adults are the same individuals as last breeding season.

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Several minutes later he ended up flying the food he had to one of the large trees in one of the NE backyards, and one of the fledglings ended up with it.

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About an hour later, one of the fledglings on a low branch in the same area:

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Aug 4: In the morning around 8am both fledglings were again quite active in the NE area of the park, with one fledgling ending up with food, but it was unclear whether it had a delivery or had obtained the item itself. Flying from the trees along the E border over to the N border with part of the food item, it appeared to be the remains of a robin:

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On a daily basis, especially in the early morning through about 9am, and in the early evening until dusk the fledglings have tended to be in the park and active, potentially chasing things, or chasing each other, as well as roosting and making whistling vocalizations for the parents.

Aug 9: In the morning starting around 8am, one of the fledglings was active and making some swooping flights potentially practicing locking on prey.

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Some significant action started around 08:15, as a group of 4 or 5 crows came into the park and instead of proceeding through, ended up stopping in the area along the S edge of the park. This sparked a sequence of interactions with at least one and perhaps both of the Coopers fledglings, with the crows landing in different spots and making a lot of harassing caw vocalizations, along with some flights which looked to be intended to harass and discomfort one of the roosting Coopers, by passing close and occasionally following the Coopers to a new roost. In response, there were also at least three or four direct pursuits by the Coopers of one of the crows, tail chasing and perhaps attempting to capture, but without doing so. The interactions were occurring over a period over approx 45min, with some breaks. Both the crows and the Coopers interacted in several areas, from the trees in the S area, over to the N border of the park, and finally to the trees relatively close to the nest area. Finally the crows appeared to gather and move off to the west of the park.

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Aug 11: In the morning both fledglings were doing quite a bit of chasing each other on the ground as well as some chasing flights. One fledgling interestingly was jumping up and down grasping a broken branch on the ground perhaps as practice grasping and striking. There were also some attempts by both fledglings to chase/harass squirrels in the NE area, although neither made any contact.

https://www.youtube.com/watch?v=V0dDC4S-Q4g

Aug 13: Around 11am, one fledgling flew into the trees close to the nest area from the S and settled into one of the common perch trees. This was the only sighting on this day, and there appear to be quite a lot of robin fledglings and other birds starting to move through and enter the park. This may indicate that the Coopers are not present nearly as much.


ostrich
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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Thu Aug 22, 2019 7:41 pm

Aug 17: In the morning I found one of the adults roosting near the nest area, it was raining out and the adult just appeared to be idle enduring the showers. There was not any sign or vocalizations of either of the fledglings that might food beg from the adult which suggests they weren't around. About 30min later I spotted an adult (quite possibly the same one but not certain) sitting on a light pole about 700m NE of the nest area. I have not had any further sightings of either fledgling in several days now so I am expecting they have dispersed.

Aug 23: I spoke to a gentleman who lives on a street not far NE of the park which also borders on the local high school property, and who has bird feeders in his front yard. He told me that he observed an adult Coopers and had some pictures of it (presumably one of the territory adults) that had captured a pigeon and was depluming and consuming it. Apparently the adult stayed roosting in the trees for a couple of hours after consuming the pigeon.

ostrich
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Joined: Mar 12, 2018

Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Wed Oct 16, 2019 4:53 pm

This is a wonderful video absolutely chock full of top notch information on the Coopers, quite a bit of these same findings are also part of Dr. Rosenfield's book which Hancock House just published.

https://www.youtube.com/watch?v=nLj_R30ZKaA

I was told by the author that the hardcover version has a few tidbits of information that the softcover doesn't.

https://hancockwildlife.org/hancock-hou ... pers-hawk/

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