Coopers Hawk (accipiter cooperri)

[ostrich]

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.







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]

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



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]

There is some interesting content here on Coopers breeding season in Seattle;

https://www.youtube.com/watch?v=J1UjuI3wEt4

Some other Coopers related material:

https://robandtheanimals.blogspot.com/2 ... uy9_Nu2TSY

https://www.facebook.com/FieldGuidesPod ... 0325258929

https://amornithnews.org/2017/12/13/urb ... neighbors/

http://blog.aba.org/2015/07/the-how-and ... hawks.html

http://www.startribune.com/cooper-s-haw ... fresh=true

[ostrich]

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



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.



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.



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.



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]

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:





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.



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.



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



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:



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.



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.







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]

https://www.krqe.com/news/albuquerque-m ... YM1OA15p3M

[ostrich]

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]

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/

[ostrich]

After quite a long time without seeing any Coopers around the area, this afternoon just outside the park I saw a Coopers glide by overhead heading into the park and dive down as if perhaps pursuing something. When I walked over to find the bird roosting in a tree along the NW area of the park, it was a juvenile.



At the same time, directly across the street from the edge of the park was another unexpected visitor, a merlin that was perched on top of an antenna.

[ostrich]

Today I came across an adult Coopers approx 800m or so NW of the park area, sitting on a light pole beside the road. It's conceivable this bird is one of the territorial adults but it is of course hard to be sure.

https://www.youtube.com/watch?v=tlbfUmtR9s4

[ostrich]

This young Coopers had a bit of adventure in an indoor mall:

http://www.providenceraptors.com/2020/0 ... ce-arcade/

[Philjo56France]

Superb photos and videos Ostrich. and

[ostrich]

Feb 2 - I had a sighting of an adult Coopers high on top of an antenna on top of an apartment building which is ~800m east of the park area. It's not as common to see the Coopers up on those very high perches -that same building is one I've seen RTs on a number of times.

[ostrich]

Feb 22: I came across one of the High Park Coopers, close to their nest area from two years ago (but apparently not used successfully last year). This bird seems to have a small distinctive abrasion across the front of the beak.

[ostrich]

Mar 5 - I got my first adult back in the Silverthorn territory about 6:30am in the morning, there was one adult making a couple of kik announcement calls from a tree in a yard just off of the NE corner of the park. After roosting there for a few minutes it suddenly flushed into the park and started chasing a passerine and ended up heading out the N end of the park. I walked out and back around to the SE entrance to the park, and noticed the adult was back and roosting in a tree just near the entrance. I did not see any sign of a second adult yet, but it appears that at least one (likely the male is back on territory).

Mar 2- At Colonel Samuel Smith park, I scouted out an area near the Big Bowl for possible activity after the juvenile pair that attempted to nest there last year. I did spot one individual in a tree just off the small bowl (which is directly across from the Big Bowl), it flew past towards the Big Bowl, but I lost sight of it and did not see a second adult.

Mar 4 - I checked a second area at Colonel Sam, along the north creek wetland, and heard an adult making kik vocalizations towards the south end of the wetland. A young juvenile RT landed in a tree nearly across the path, and the Coopers reacted by flying at it and flushing it, and then chasing it out of the area, a clear territorial behavior. So this is solid evidence of a territory nearby (but again not a second adult on this occasion).

[ostrich]

Mar 11: I went out early in the morning in the park to check for activity, and I heard some vocalizations coming from the trees just near the N entrance to the park. I saw one Coopers fly across over into the lower trees immediately across from its perch, after which it subsequently flew over into the conifers along the NE edge. After hopping around a number of times among the conifer branches, it then moved to the adjacent large deciduous tree. The interesting part is that this bird appears to be a juvenile female:



The juvenile bird continued to make periodic kek vocalizations, and after a couple of minutes an adult male flew in and perched lower in the same tree. So it appears that there is for the present a new female in the territory.



While the adult male roosted nearby, the female continued to move a couple of times to different trees and making quite loud vocalizations, it seemed to be working hard to get the attention of the male, although not with that much obvious response.

After leaving the park for approx 30min, I came back and found the juvenile female roosting in a tree in the yard just beside the E entrance to the park:



Finally, she flew off her perch and over several of the houses and ended up back on a pole just outside the park entrance for a couple of minutes:

https://www.youtube.com/watch?v=N7eV06ZWIEk

Mar 17 - I was out in the park at approx 7:20am, and shortly found the adult male making some kik calls along the N edge of the park. I then spotted the juvenile female in the large tree just at the NE edge, she was reaching down to her feet and brushing back and forth with her beak, so she might have been just finishing off a food delivery from the male. She was responding to the male's vocalizations so they appeared to be interacting. This suggests that this female is indeed going to be sticking around in the territory, barring the previous female showing up and getting into the territory again.

https://www.youtube.com/watch?v=f7m4l-SHGOM

[ostrich]

Nov 12: I had my first sighting of a Coopers in the local area since the spring, just E and a bit N of Silverthorn Park. This adult was perched in a tree in the front yard of a house right at the edge of some open fields which are part of the local high school E of the park. This house has a number of bird feeders in the front yard and often has quite a few pigeons, as well as passerines and squirrels around. The Coopers was clearly watching the feeders.

Several minutes afterwards it flew down to some other trees bordering the backyards farther E.



https://www.youtube.com/watch?v=lu6mV8xvcso

Nov 26: Just walking back to my building just immediately S of the park at around 4:30pm, some passerines flashed past some of the trees near the building and then a Coopers passed right by and flew past the N side of the building and then into the park. I was able to locate in some of the trees towards the middle of the park close to the N entrance and it had made a capture and was consuming it. However it then flew off with the prey and I lost track of it. However this is more indication that there are certainly Coopers active around the area, the first clear observations I've had of that since the merlins have been in the area.

[ostrich]

Nov 29: In the early afternoon I had an interesting sighting, there were two Coopers soaring together over the south end of the park, they were reasonably high and did not appear to be hunting, but were more or less circling around and flying as a pair. This suggests there are at least two different individuals in the area, and their behavior could be an early male-female or courtship type interaction.

Some time later after seeing both hawks continue flight out of sight out of the park area, I did hear kek vocalizations coming from somewhere close to the building at the SW corner of the park. I was not able to find where the vocalizing bird was - however it also is a hint at interactions between the pair, as usually individuals on their own rarely vocalize.

Dec 1: In the morning around 9am I again found an adult Coopers roosting in the same trees near bird feeders bordering the athletic fields just E of the park. This is a good indication at least one individual is regularly hunting these feeders.



https://www.youtube.com/watch?v=klS9SJjkVKs

Dec 4: I had a brief sighting of a Coopers in early afternoon passing across the road just a bit further E from the same spot, passing across the road from S to N, and down through other backyards that border additional sidestreets in the same area. So the bird likely was also hunting other spots in and around there.

[ostrich]

Dec 17: Another sighting of an adult near the same bird feeders.

[ostrich]

Dec 25, another sighting of an adult, which flew into some trees approximately 30 yards away from the same feeder area and then left.

[JudyB]

I’m guessing you haven’t seen a resident pair here before, so this may be a new territory? It will be interesting to see how they make it their own.

[ostrich]

I’m guessing you haven’t seen a resident pair here before, so this may be a new territory? It will be interesting to see how they make it their own.

These birds I'm spotting near the feeders are mere seconds as the Coopers flies from the center of the Silverthorn Park territory, so it's reasonable to assume they are part of that territory. Whether they will resume using it as a nesting area after last season's hiatus will be interesting to see (but there was one other similar hiatus back in 2016 I think).

[ostrich]

Jan 10: I got a sighting of two Coopers in the area of the feeders by the athletic fields, once flew into some trees just across the street, and while it was there a second one came in, and seemed to swoop through where the first was, it was hard to see what interaction there was, but there were some vocalizations. Then the 2nd one that had come in kept going to the west out over open field and roughly towards the park.

Jan 11: Around early afternoon there was one individual perched in the trees in close to the same area.

[ostrich]

02/28: I was out in the park early, around 6:40am and was able to catch individuals in the park for the first time thus far this spring. I observed one adult individual that was making kik calls in the NW corner of the park. Over several minutes it moved to different spots along the north edge of the park after approx 30 seconds of making kik calls.

After it moved to one of the large trees in the NE corner, a second Coopers that also appeared to be adult came in and ended up flushing it from its perch (but I do not believe there was any food or food exchange). From there both birds ended up in the trees along the S edge of the park, and then back to the NW corner over a couple of minutes. Finally they left the park out of the N edge.

[ostrich]

With the Silverthorn Coopers hawks not nesting in the park the past two years, sightings of individuals have been much more infrequent, however yesterday some loud calls by blue jays pointed out an adult Coopers at the N edge of the park (from size it looked likely to be adult male).

[ostrich]

Unfortunately so far there has been no obvious sign of presence or nesting activity in Silverthorn Park, so it appears likely the territory is no longer active again. I have sighted individuals in the area occasionally so there is still presence but I don't know exactly where they are.

04/01 There was an individual not far NE of the park.



The hawk was being followed around and harassed a fair bit by a crow. I've seen quite a bit of crow activity in the neighborhood so there might be a crow territory somewhere.

[ostrich]

The Coopers hawk pair at Colonel Samuel Smith park seem to be preparing for nesting, over the past week they have definitely been constructing a new nest in a deciduous tree at the SW edge of the little bowl area, which is in the NE corner of the park. It's definitely been added to in the last week, and yesterday morning the male was continuing to fly sticks up to the new nest, along with mating. But it did not appear eggs have been laid yet.

[ostrich]

An interesting situation has arisen in a territory I was able to find earlier this spring - this territory is in Martin L. Dobkin Park, which is roughly 3km west of the Silverthorn Park territory. The park borders the property of two schools, which have some athletic and other fields, and two separate wooded areas on either side. I had checked the area in early April, as the wooded areas looked like good potential nesting areas, although I was not aware of any past presence there.

On April 6, I located two adults in the wooded area on the west side of the park, there was a nest structure under construction in a tall deciduous tree. Both birds were in full adult plumage.

Male:



Adult female:



Some footage of the pair:

https://www.youtube.com/watch?v=HAkZfoH2T_M

On a couple of occasions between April 6 and April 20, I'd checked the area and observed the adults on some occasions both in the original area in the west side of the park, but also working on an alternate nest being constructed in the trees on the east side. By Apr 20, the pair had clearly chosen the latter nest site, as the female was observed in incubation position on the nest.

On Apr 30, I visited the nest site on the east side in early evening at approx 18:50. Walking towards the nest area I was able to spot the female on nest. Around 18:53 I spotted another Coopers flying towards the line of trees near the nest from behind me and landing in a tree approx 20m from the nest tree. I initially assumed this would be the territorial male coming in perhaps to make a food delivery or visit the nest area. However, upon approaching the new bird I was surprised to discover a bird in juvenile SY plumage, and from general build and size the impression was a female.



At 18:55 the adult female was still present on the nest, despite the SY (female?), but the territorial male was not around. However she behaved like potentially she had noticed and reacted to the presence of the SY individual.



Although I did not unfortunately see the actual interaction as I was attempting to walk to a better vantage point, but between 18:56 and 19:00 the SY female had apparently displaced the adult female from the nest, the latter having landed in a tree nearby, while the SY female stood in the nest, looking inside briefly and perhaps taking an interest in the contents. After several minutes the SY female left the nest. By 19:07 the SY bird had apparently left, and the adult female was still off nest, but periodically making whaa calls. I don't know if those were possibly intended to attract the attention of the territorial male for assistance in resisting this intrusion, but no other adult was present while I was there.

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

On May 1 I was able to see that the adult female was still present and on the nest, however I quickly found that the SY female was also sitting again near the nest area.



After this I did witness the SY female flying up towards the nest and try to enter and presumably displace the adult female again, the adult stood up and reared up and the SY bird stopped short of landing on the rim and subsequently flew off to the other end of the park. So at this point it seemed clear this SY bird was indeed actively trying to usurp the territory and/or the nest.

By my check on Apr 2 however, there was no longer any sign of the adult female on the nest or nearby - nor was the adult male in evidence. The SY female was still present and I observed her bringing a stick up to the existing nest, https://www.youtube.com/watch?v=AfQHODD-Pqc

On Apr 3 and Apr 5 I have observed the SY female on both days also apparently working on a minimal nest structure in a different tree across the wood from the original (abandoned) nest. When bringing sticks to this new nest, this SY female has made audible kik calls a couple of times after landing. This is a less common call for females to make but they will occasionally do so.

On Apr 5 from approx 07:15 - 07:55 there was no presence in either the nest area or the wooded area on the W side.

- at approx 07:55 the SY female arrived in the east wooded area with a faint kik vocalization upon arrival.
- at ~08:00 the SY female broke off and flew a stick up to the small/initial nest structure, making clear kik vocalizations on the first flight up to this structure. From 08:00-08:15 the female continued building activity on this nest, periodically breaking off branches and flying sticks up a total of 8 times, along with a few occasions of sticks being dropped or abandoned before being placed. There were no vocalizations upon later stick deliveries after the initial one.
- at ~08:30 the SY female flew one stick up to the abandoned initial nest and again made a kik vocalization upon doing so. Then she left the nest to roost in a tree along the N edge of the wood. No adult birds were observed in the area during this period.

https://www.youtube.com/watch?v=ps9Jh4NwBuY





Standing in original nest

[JudyB]

Interesting behavior indeed, ostrich - thanks for posting it here. I don't know much about coopers hawks so am extrapolating from eagle behavior, but I am wondering if something happened to the territorial male. I don't know if he'd challenge a female, but if they were eagles, he'd likely come in to protect the nest so the female who was nesting could go after the young female. Please let us know what happens next.