Coopers Hawk (accipiter cooperri)

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sat Dec 01, 2018 2:15 pm

This video has got some interesting footage of a juvenile Coopers hawk bathing.

https://youtu.be/5yNHg8GCwgc

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Thu Dec 13, 2018 4:56 pm

Dec 12 - I again had a brief sighting of an adult Coopers today, flying overhead a couple of streets north of the park.

Dec 16 - on my way back from xmas bird count, I had a brief sighting of an adult around 5pm a couple of blocks S of the park flying across the road between some industrial buildings, maybe looking for pigeons.

Dec 25 - around 11am I spotted a Coopers roosting on a light standard beside the road about 50m N of the church (a main block N of the park). It was interesting that a northern (abieticola) RT that has been around for a few weeks now was also roosting on top of the church at the same time.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Fri Dec 21, 2018 7:42 pm


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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Jan 07, 2019 6:21 pm

This is an article on a possible Coopers hawk-northern goshawk hybrid.

https://adventuresinmothland.wordpress. ... Ouxx8wel6w

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Feb 04, 2019 10:14 am

Feb 4 - today at noon I had my first sighting in a while, of an adult Coopers up on top of the church, present for perhaps 10-15min.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Tue Mar 12, 2019 6:03 pm

Mar 11 - this morning I went out to the park at about 6:15 for the first time to look for activity, at about 6:45 I did have a Coopers glide into the park from the west entrance, and glide around eastward for a bit, before turning and heading towards the daycare yard and trees towards the S edge of the park. I couldn't tell if it stopped at all, when I walked over to look I couldn't see anyone in the trees. So I'm not positive if this was one of the residents or not.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sun Mar 17, 2019 8:48 pm

Mar 15 - I went out to the park at ~7am to check on activity, and there was already one Coopers sitting on a tree branch in the area at the S edge of the park, and both adults were present (although I could only hear the other's vocalizations from some where off to the right closer to the building). The visible bird had some type of food, so it's possible there was a delivery. After several minutes there were more vocalizations from the other bird, and the visible one flew off to the right to the park edge and out of sight.

https://www.youtube.com/watch?v=tm2sgITHI-M

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Tue Mar 19, 2019 7:13 pm

Mar 19 - today there was noticeable activity in the park, passing by the park at about 9:30am, I noticed both adults perched together in the area close to the existing nest:

Image

The female appeared to be just roosting while the male was going back and forth a couple of times and trying to break off sticks, so this was the first definite nest building activity I have caught thus far

Image

Image

Going by the park again around noon time, the female was still sitting in the same area, so this is also a sign of increasing presence in the park over just short pre-dawn activity.

At ~6:30pm another check had the female once again roosting around the same area, with the male flying past from the park edge, heading in her direction. He did not appear to stick around, but there were quite a bit of vocalizations.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Thu Mar 21, 2019 5:10 pm

Mar 21 - Both yesterday and today, checking the park when passing by both early in the day (~9:30 am) and late afternoon (around 5:30pm) there was adult presence (female) in the trees in the vicinity of the nest. This is indicating that the female is spending substantial amounts of time in the park area now.

Mar 22 - This morning at ~10am, when walking along the sidewalk just off the W entrance of the park, an adult flew low over the road and into the park going past the nest tree and further on, but upon checking there was no sign of either adult in the trees, so it did not stop to roost on this occasion. This evening the park was empty.

A recent article on urban accipiters.

https://www.allaboutbirds.org/seeing-mo ... agination/

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Mar 25, 2019 6:35 pm

Mar 24 - I visited the High Park Coopers territory early in the morning to look for courtship activity, and found the adults vocalizing close to last year's nest tree. There was a brief copulation, followed by the female leaving, although periodically she was continuing to vocalize from different locations close by the same stand of trees. I did see the male break off a couple of sticks and fly them up into last year's nest.

I saw my local female briefly a little later in the morning, and around noon time after going out, I found an adult up on top of the church north of the park.

Image

Image

Mar 25 - my local female was again roosting in the park around the nest area at around 9am.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Thu Mar 28, 2019 7:55 pm

Mar 27 - I was able to check the park fairly early at around 7:15am, and both adults were roosting near the nest, the male did make two or three trips back and forth to break off small sticks and fly them up to the nest during the time I was watching.

Mar 28 - Around 9am one adult was roosting near the nest, interestingly I spotted another accipiter a few minutes later farther up a block further north from the church, but I don't know whether one of the residents would normally wander up that far.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sun Apr 07, 2019 5:26 pm

Apr 4 - I went out to the park at about 9:15am, I did not see the female in the typical spots near the nest tree, but then I heard some whaaa vocalizations coming from further back, along the N edge of the park. I found the female roosting fairly low in a branch of the small trees/bushes along the N edge right beside the N walking path exit to the park.

Image

In high resolution it appeared that the female may have eaten recently, as there was some blood on the feet and a bit around the edge of the beak. She continued periodically make whaaa calls which are her typical vocalization when communicating with the male, although he was not anywhere in sight. However she may either have been making calls to request food delivery, or she may have been able to see him somewhere in the distance. However the male did not make an appearance during the period I was there. However the shots of the female also did yield a useful piece of information, the middle toe on the left foot above has somewhat of an unusual/bulbous shape, as if perhaps an old healed fracture or some other injury to the toe. Upon going back and reviewing other shots of the female from last year, this shot from almost exactly a year ago shows the same kind of unusual shape to the middle left toe. This is pretty good confirmation that it is the same resident female in the territory.

June 22 2018:
Image

Footage of the female vocalizing:

https://www.youtube.com/watch?v=TlYyId7bVzw

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sun Apr 07, 2019 5:31 pm

Apr 6: Going out in the morning around 8am, both adults were in different branches of the nest tree below the nest. I hoped to get close shots of the male especially for identification purposes, but before I could return with my camera the male flew up briefly to the nest, and then flew to one of the usual roosts just away from the nest tree. The female took some interest in a squirrel which was moving around high in the nest tree but did not make any other moves toward it.

Later in the afternoon around 1:15, I found both adults roosting together near the common perch, and after some quick vocalizations from the female the male moved and I was able to observe copulation. As was the case last year the male is markedly smaller than the female, which is often the case with Coopers:

Image

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Thu Apr 18, 2019 7:22 pm

Apr 16 - I have not been able to check the nest for the prior week, but on checking the nest area in the morning, both male and female were roosting together close to the nest area. The nest structure appears to have been added to visibly.

Apr 17 - in mid morning, I caught the female briefly on the nest poking around in the rim before flying back off to the trees.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Thu Apr 25, 2019 4:49 pm

Apr 21 - I saw the adult female sitting on the nest for the first time in the morning in incubation position, which is likely at least a sign of impending egg laying, but might or might not be a definite indicator of actual laying.

Apr 23 - I did not see the female on the nest either of the times I checked, on one occasion she was roosting in one of the usual spots nearby the nest tree.

Apr 24 - In the morning, I saw the female just flying from off the nest from the west direction up into the nest. She appeared to be rummaging around in the bowl during the time I observed. Later in the day she did again appear to be in an incubation position.

Apr 25 - in the morning about 8:30am the adult female was on the nest, standing upright at the edge of the bowl, but did not seem to be overtly sitting. Shortly thereafter she flew off the nest low over the houses immediately N of the tree, and she was vocalizing, it could have been some delivery or arrival by the male. This evening around 5pm she was again in the nest in the same upright position, but not in overt incubation position.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Apr 29, 2019 4:21 pm

Apr 29 - I am now tentatively pretty confident that incubation has started, yesterday and today I have been consistently seeing the female on the nest after several checks during the day. Yesterday both male and female were present in the morning (around 7:00am), and later in the morning at about 11:30am. The female was on nest in the early evening at around 6pm.

Today the female was on nest at ~9:30am, and was also on nest when I went by at ~5pm and 6:30pm, but the male was not around. It was raining and temperatures have been relatively cold today so it would make sense for her to be on nest if there are eggs.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Thu May 09, 2019 6:59 pm

May 9 - I have been regularly seeing the female on the nest in incubation as normal for the past couple of weeks, and occasionally seeing the male as well. Today around 3pm I went by the park and sighted an adult on the nest flat in incubation position, then walked to the other E end of the park and spotted what appeared to be the male in the big oak tree in the NE corner, pulling at a fairly large prey item (it looked completely deplumed but appeared to be roughly robin-sized).

https://www.youtube.com/watch?v=EN87CEJjmvI

I watched the adult working on this prey and consuming parts for approx 10 min before I left for an errand. Returning briefly about 15min later the adult was from the tree, but both adults were close to the nest (one roosting across from the nest tree, the other in the nest. So probably after finishing processing the prey item it was brought over for the female but I didn't see the delivery.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Wed May 15, 2019 5:32 pm

May 10 - In some of the wet and somewhat cold weather that's been around quite a bit this spring, I found the male roosting near the nest and looking pretty bedraggled in the rain:

Image

May 13 - in addition to seeing the female in the nest consistently, I sighted the male in early evening again roosting across from the nest tree presumably after a recent visit or food delivery.

May 15 - Early evening, the female was in nest and the male roosting in his usual spot across from the nest tree.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Wed May 15, 2019 5:59 pm

There was also been a very interesting nesting situation at another territory in Colonel Samuel Smith Park, down on the lakeshore, right now there is a pair nesting in a deciduous tree in the NE corner of the park. The unusual aspect is that both nesting birds are SY birds (still in juvenile plumage).

Female:
Image

Male:
Image

This is a highly unusual situation, breeding SY females are not common, but are known in Coopers hawks, but SY males are rare. There is some data on this in Robert Rosenfield's book

https://www.hancockhouse.com/collection ... 5218945069

In the Wisconsin long term study described, only 2% overall of nesting attempts involved a SY male, it is also interesting that the occurrence of SY males also seemed to be strongly biased towards a relatively new colonizing population that is growing. On the surface this seems unlikely to be the case for CSSP since Coopers hawks have been a common nesting bird in the city for a substantial period of time.

There have also been reports that are unconfirmed that there might be a second pair of breeding adult birds in the park, as well as possibly a third pair. If either of these are present it would also make the density of nesting territories very high for this park.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sat May 25, 2019 9:03 pm

It appears perhaps unfortunately that the nesting attempt at CSSP park has ceased, at least for the time being. However there is still presence by the pair and some interesting behavior.

- 05/17 a visit to the nest area didn't seem to have the female visible on the nest, although on many nests it can occasionally be hard to see an incubating female if she is flat on the nest and her angle doesn't allow her tail to be easily visible sticking out over the side.

- 05/19 At 09:15, the nest again did not appear occupied, but after a short time near the nest area some kik calls were audible by the SY male. He was spotted in a tree fairly close to the nest.

Image

Over the next 10-15min, the male did show behaviors of flying occasionally to different tree branches and pulling at them, attempting to break off, consistent with typical nest building behaviors.

Image

Image

One flight was observed possibly carrying a stick to a conifer on the opposite side of the big bowl/depression directly west of the nest tree (approx 30m away), where glimpses of what presumably was the female were visible without a clear view. However some vocalizations which were likely copulation were heard from the tree shortly afterwards.

05/20: At ~06:35, the nest again did not show any sign of occupation, but within 5-10min some kik calls from the SY male were audible from adjacent trees. Searching the trees did locate the SY female, with deplumed (appeared to be passerine) prey which she was consuming. Within seconds the SY male flew in from some nearby location and copulated with the female.

Image

The male left after copulation, and the female eventually flew into a conifer on the near side of the large bowl (closer to the nest tree, within 10m). However any new nest structure was not clearly discernable in these trees.

05/23: At 07:00, nest empty, and only caught one kik vocalization and a brief flight of one of the SY birds flying down the large bowl in a southward direction.

05/24: 06:15, from passerine alarm calls, the SY male was located in the vicinity of the nest site, again engaged in stick breaking behaviors (moving periodically to different tree branches and twisting with beak),

Image

After several attempts a very long branch was flown away in a southern direction to another small bowl filled with mainly deciduous, and a couple of coniferous trees, which is ~150-200m south and slightly east of the prior nest tree. Finding the SY male in these trees, there was a very small start of a nest construction in one deciduous tree, with the male bringing sticks to it.

Image

Image

So it appears that the initial nesting attempt (which certainly seemed to have the female in genuine full incubation for a noticeable period of time) was abandoned for unknown reason. Presumably abandonment occurred sometime around Apr 17, consistent with other reports from other park birders. Perhaps some reasons could be:

1) Human disturbance: under normal circumstances territories in the area have always seemed to be very tolerant of human activity, so just ordinary presence presumably would not cause this unless there was something especially different about this female's behavior. There have been some concerns expressed about potential drone activity nearby, as one drone operator was observed fairly close to the nest (although not flying directly near it), this was on 05/21, but it leaves open possibility there could have been other previous drone flying. Whether this would affect them to the point of abandonment is unknown.

2) Egg predation by nearby mammalian predators, there are quite a lot of squirrels in the trees immediately surrounding the nest tree, although a squirrel seems less likely to be able to predate eggs from a Coopers female (other than perhaps factoring in that the bird would be nature of being SY be relatively inexperienced). More likely a scenario would be raccoon, as these are definitely present in CSSP and are seen in the area near to the nest.

3) An inability of the SY male to provide food deliveries serious enough to cause nest abandonment. There doesn't seem to be any significant indication of this though, and the fact that food deliveries certainly seem to be continuing from the male post-abandonment certainly suggest his hunting is at least adequate. The biggest hunting burden that might be difficult for the SY male would presumably occur after hatching as opposed to before.

It also seems clear that the nesting abandonment has not resulted in departure from the territory, and the pair have gone back to a number of courtship behaviors, it remains to be seen if there is a full nest construction or not. I don't know if they would actually progress again all the way to egg laying (other pairs in the general geographical area would be getting close to hatching in the next week or so, so they would be several weeks late). If they did so, would they be able to successfully rear young hatched a full month later than the normal window, also being SY birds, is also unclear.

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Jun 17, 2019 6:05 pm

Some recent observations:

05/31: At about 9am, the male was already on bare branches just across from the nest, with the female incubating, there was no evident food exchange in progress, male was simply roosting and preening.

Image

After several minutes of preening the male made a very short flight into the maple trees just behind and to the left of the roosting spot. He seemed to make two or three short partial flight/hops onto nearby branches within the maple tree. A quick walk around to the other side of the park to see if he could be spotted from the other side didn't yield anything.

Upon returning around to the other side, the male seemed to have a food item that he slew over to a separate tree branch spot about 10m on the east side, by 09:15 the female now had the food on this branch. It seemed possibly like the male could have been hunting for passerines in the branches of the maple tree, although with a method I had not seen before. But it also seemed surprising that if he had made a capture he could have entirely deplumed the prey in the short time (maybe a couple of minutes) taken to walk back around from the other side. However after further observations I believe the male may instead by caching food items on one or more of the tree branches on a couple of spots near the nest. This would also be something not observed before.

Image

After consuming quite a bit of the food, the female with a noticeable crop. Subsequent to this there was no indication of the food being brought to the nest though, so this would be likely indicative that no hatching had yet occurred.

Image

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Jun 17, 2019 6:38 pm

06/09: From several false alarms over several days of seeing the male around the nest and hoping to catch an actual food exchange which might confirm food being brought to the nest, I finally got definitive sign of a feeding. However from the female's behavior (especially high sitting position and subtle indicators of posture on the nest) I strongly suspect there would have been hatching sometime in the several days prior (which would be consistent with likely laying dates and prior hatching dates), but without feeding as a definitive indicator it is hard to pin down.

17:00 - the male arrived in the vicinity of the nest and made a kik announcement call, which this time did prompt the female to leave the nest and eventually make a food transfer. After several minutes of walking around trying to get a better vantage point, several minutes later, the female did return to nest, and the male did also come back to the nest tree, roosting just off and under the nest bowl. However initially the female seemed to be just crouching/lying on the nest, it wasn't evident she had brought the food back and was actually going to initiate a feeding. After a couple of minutes the male hops up to just above the bowl, there are some kek vocalizations, and then the male leaves.

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

However, by 17:07, after the male leaves, the female is there visibly pulling off food pieces and offering them into the bowl, although any hawklets are not large enough to be visible over the rim. But this seems to indicate the female did bring the food back but did not initiate feeding right away for some reason.

https://www.youtube.com/watch?v=UZYFtKEGV-A

At one point shortly after the feeding commences, the male comes back into the edge of the nest (which is itself quite uncommon generally over the years during a feeding), it looks like he may also have had another prey item in one talon, although it's difficult to see behind leaves. He then departs and it is difficult to tell if he leaves the food item behind (which would also be a pretty unusual behavior) or takes it with him again. After a number of minutes of feeding the female finishes and settles back down on the nest.

https://www.youtube.com/watch?v=arHXD8Fv3ug

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Jun 17, 2019 7:49 pm

06/14: 17:51, the male arrived in the park from the east carrying a food item, and again there was a rather interesting sequence of interaction that seems quite different than the typical pattern from previous years. After walking around and coming back to the nest side, the male appeared to have food at one of the nearby bare roosts. However, upon initial checking of the roosting male, the food wasn't clearly visible in his talons and he wasn't consuming or processing anything, so it was not initially clear if he'd cached the food or had it. However, after a couple of minutes, some kik calls were clearly audible (although not picked up as well by the mic) in the trees quite close to the right. This led me to suspect I had the adults reversed, and it was the female who had come down to roost. However this suspicion was reversed when the adult making the kik call came in and was clearly the female from sheer size difference, at which point she claimed the food which was still sitting nearby, and the male immediately retreated. This is also a rarity, with the female making a kik type call.

By 18:07, the female did bring the food back to nest and began to feed. On this feeding at least one hawklet was just visible popping up at the edge of the rim from time to time, but not clearly enough to determine how many. But the hawklet appeared to still be in full white down. After several minutes of feeding, the female flew off nest, still carrying some remainder of the food to the nearby trees, but it is unclear if she went to consume or possibly stashed the remaining food in the trees.

By 18:16, the male flew to the nest, where the female in quick succession flew to a tree immediately beside the nest tree, then up to the nest displacing the male, and returned to brooding, whereas the male returned to original roost.

https://www.youtube.com/watch?v=ZB-NpYJVPEs

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sun Jun 23, 2019 4:42 pm

06/21: approx 18:20, there was already a feeding in progress on the nest when I arrived at the park entrance, observing the feeding and just taking still shots, there were two hawklets much more clearly visible reaching up as food was offered. These two were definitely noticeably larger and could be seen much more easily when not lying down lower in the bowl.

Image

Approximately 20-30min later, there was again food brought in (but unclear where the food exchange or delivery occurred), although it was quite brief, and just setting up to record only caught the female just finishing, and actually flying off with a still substantial prey item. Since there was a recent feeding that was likely fairly substantial, it seems possible the hawklets were not as hungry on this occasion and the female ceased feeding early. She flew the prey somewhere into the nearby trees but it was not possible to see whether she consumed the prey or not. However she did not stay off nest for more than a couple of minutes, which may suggest she did not consume, or entirely consume such a large piece of prey. This is another item of circumstanial evidence that suggests they may be at times caching prey in the nearby trees. Upon her return to the nest, one of the hawklets did get up much higher and was standing near the rim, if a bit unsteadily at times. The hawklet visible did seem to be still fully in white down, although there may be pin feathers developing underneath.

https://www.youtube.com/watch?v=eCFfCySMsy8

06/22: approx 3:50pm there was a nice long feeding in which there were good looks at two hawklets reaching up for food, these two heads were the only ones visible participating in the feeding, so this appears to be very good confirmation once again that there are two hawklets in the nest this time, if there were a third hawklet it would certainly have been visible during the feeding.

https://www.youtube.com/watch?v=oQme46yqGRs

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Jul 01, 2019 1:35 pm

06/26: Further development of the hawklets, around noon time there was a feeding in progress on the nest, with both hawklets nicely visible and at times standing up fairly high to face the female and grab pieces of food. One of the hawklets stands up and lets off a slice, and there are definitely pins visible on the primaries and secondaries, although still a lot of down still present. Approx 3 min into the feeding, one of the standing hawklets has quite a substantial crop.

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

Approx 4pm I was able to observe another feeding, but without any footage. But overall food deliveries seem to be fairly regular through the day.

Standing hawklet showing some development of the secondaries.

Image

06/30: Another feeding with some decent footage of the hawklets, there is some evident loss of down and pin feathers becoming more visible, but at this point both seem a fair amount away from complete growth. Again approx 2:30 into the footage there is a good view of the extended wing.

https://www.youtube.com/watch?v=mzOQrpNhrG4

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Jul 08, 2019 5:20 am

07/01: I was fortunate enough to catch the adult female very low in the nest tree only about 10 feet off the ground which allowed for some good close footage.

https://www.youtube.com/watch?v=5MmIIwAFMFc

https://www.youtube.com/watch?v=_yvhM_HvU3Y

Image

07/02: Some very interesting observations, in early evening around 7:45pm, the male flew in from west of the park and landed in tree close to the nest carrying a sizable food item. However he did not make an audible kik call, although the female did fly down from the nest tree and swooped down low, but not to where the male was, she seemed to land somewhere low out of sight behind the houses and trees immediately east of the nest tree. After about a minute, the male flew the food directly up into the nest himself and started feeding both hawklets. This is something I have not witnessed before, and was not evident until it was clear from the footage that several minutes into the feeding, the female came back, paused briefly beside the bowl, then came in and displaced the male. Interestingly, she also took the remainder of the uneaten food herself and flew off with it instead of continuing the feeding. This is the first time I have gotten clear evidence of the male attending the nest and feeding in this way without the female. There did not seem to be any announcement vocalization, or typical exchange sequence with the female. I'm uncertain how unusual this type of behavior actually is.

https://www.youtube.com/watch?v=UNn1tBTyKt0

After the feeding was completed, the hawklets did start doing and flapping and wing exercising, with the female coming back up and landing in the adjacent branches. Since this return was within a couple of minutes of departure, it again seems likely she did not simply consume it but may have cached some remainder:

https://www.youtube.com/watch?v=29bLSrChsSc

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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Mon Jul 08, 2019 5:34 am

07/04: Catching a brief feeding on the nest, as well as the hawklet activity after the feeding provided good views of the feather development, with increasing loss of down and good emergence of all the primary and secondary flight feathers:

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

https://www.youtube.com/watch?v=8q-ZJjRoH3s

Image

Image

Image

07/06: First confirmed branching of one of the hawklets, with one of them having moved at least a short distance out of the nest bowl and along one of the supporting branches:

https://www.youtube.com/watch?v=YYeV3FLOWY4

07/07: In the morning, around 10am, and later close to noon, I observed two more occurrences where the male clearly appeared to be doing feeding on the nest, with the female nearby, but not participating. In these cases I did not observe any of the sequence leading to the male going to the nest, as in both cases he was already on the nest and feeding when I arrived. However in both cases as he conducted the feeding, the female was roosting visible nearby in the nest tree where she has often been roosting in the past couple of weeks. Other than making repeated whaa vocalizations, in seeming general response to the male's presence, she did not participate in the feedings.

However, later at approx I observed the male do a quick touch and go landing on the nest and drop off a food item for the hawklets to self-feed on, this marks the first occurrence of self-feeding thus far.

https://www.youtube.com/watch?v=pa0e4TEqQrg

ostrich
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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Thu Jul 11, 2019 6:54 pm

07/09: I was able to witness another interesting entire sequence in the evening, at 18:25 I observed the male fly into the park from the west and land nearby to the nest. The female was roosting in one of her favorite spots in the close tree just beside the road. The male did not make any audible kik call but the female did start making periodic whaa calls in response to the male. After about a minute or so the male again flew directly to the nest without interacting or any participation by the female and started a feeding. Both hawklets were in or close to the nest bowl when the male arrived, but one moved out along a nearby branch and did not seem interested in the feeding.

18:29 - the male then flew out of the nest and landed on the far side of the same tree the female was in, with it not being entirely clear whether he took the food with him or not. But it seemed that he likely did not. At 18:35 he suddenly returned to the nest, and this time grabbed the food item and again flew back to the same tree with it. However there was no food exchange with the female or any direct interaction this time either, other than whaa calls. By 18:39 the male moved again with the food item to another higher branch actually even closer to the female, but then at 18:41 he flew a third time to the nest carrying the food item which he dropped this time for the hawklet to self-feed on.

https://www.youtube.com/watch?v=FPTOex62M5c

Male with the food item, which appears to be part of some kind of bird.

Image

07/10: Both hawklets were showing significant increases in activity level outside of the nest bowl, moving quite a few times, on a few occasions with a fairly long flapping/jumping movement to different branches. On this occasion the female exhibited some less "passive" behavior for the first time in quite a while, flying at one point into the nest with some food and conducting a feeding herself. The male did not seem to be around, but I did not see the female's arrival, it is possible she did not exchange with him but arrived with food she had hunted.

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

07/11: Early in the morning around 7am the hawklets were already quite active and well above the bowl. At least one had reached the very uppermost branches of the nest tree but I did not see any indication of either off the nest three through the day however. There were some light rainstorms in the early afternoon, and the wind picked up quite substantially in late afternoon, which perhaps discouraged them a bit as in the evening both had returned to the nest and were pretty much hunkered down in the wind.

In the early evening I did witness the female behaving more typically and less "passively" again, the male arrived and landed in one of the frequent roost spots with a food item. Although I did not hear a kik, the female started making whaa calls, and suddenly flew right to the male's roost and displaced him quite aggressively from his perch, presumably to claim the food item, forcing him to make a sudden evasive flush when she arrived. I did not determine though what she did with the food.

ostrich
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Posts: 68
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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sat Jul 20, 2019 6:34 am

07/12: I am putting down July 12 as the first confirmed fledging, as I found one of the hawklets around 08:30 in the tree beside the road which is close and slightly NW of the nest tree. This tree is the same one the adult female has been regularly roosting in. The second hawklet was not immediately visible but I could not confirm whether the second was definitively fledged or not. The fledgling was actually reaching and pulling at leaves on the tree with its beak which is not a common behavior.

https://www.youtube.com/watch?v=FtdUKpsQ0EY

Image

Later in the day around 15:24 I again found a fledgling in the adjacent tree which is just SE of the nest tree inside the park.

Image

The second hawklet was in the nest tree and still moving around quite a bit, but also often hanging around right around or in the nest. And still without a confirmed sighting off nest.

Image

Image

ostrich
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Re: Coopers Hawk (accipiter cooperri)

Post by ostrich » Sat Jul 20, 2019 6:55 am

07/14: I finally was able to get a confirmed sighting of the second hawklet off the nest, although I suspect it could easily have been off before that. Around 06:55 after the arrival of an adult in the area, I spotted the second hawklet flying and vocalizing from the area just east of the nest tree and actually flew directly across the road into a pine tree on the opposite side. That is an unusual pattern as I've never seen them move in that direction during the post fledging process before. Generally they move primarily deeper into the park. I believe the fledgling (which I also think is the larger and likely female) was following an adult and food begging, as an adult subsequently flew out of the pine tree and back to the roost tree beside the nest. The fledgling was roosting in the pine tree for several minutes and despite the food begging seemed to have a good crop.

Image

An interesting sequence then ensued, as the fledgling then flew back across and landed close to the still roosting adult. It moved right up beside the adult and continued whistling food begging calls, despite its large crop, at one point being almost beak to beak with the adult. Unfortunately I was only able to get still shots of this behavior, once I was able to get my tripod to try to film the adult had left.

Image

A little later in the morning I found both fledglings in the nest tree with the larger one still making a lot of whistling vocalizations. This individual is very reminiscent of an fledgling from 2014 which was also large and almost certainly a female. That bird stayed longer than the other two fledglings, and was very persistent and aggressive in its food begging vocalizations.

https://www.youtube.com/watch?v=_BJNKPw2riU

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