Nesting Goshawk and predation of Sparrowhawk

I think we need a break from Grosbeaks so now something completely different 😀

I wrote earlier about four breeding species I spent time with during the spring and summer and promised that I would write about them over the winter. I began with Red-throated Diver and now is the turn of Goshawks.

Two pairs of Goshawks breed in Maridalen and one of these breeds in area with a fair amount of human activity and they seem to be at ease with this this. I also know that Goshawks breed in parks in Berlin so knew that the species can breed amongst us but I was none the less very surprised when I found another pair (not in Maridalen) which were breeding VERY close to people. This pair seems to be newly established with the nest not particularly large and no sign of other nests in the area (a well established pair will have more than one nest to choose between). I reported the pair to a biologist in the Oslo City Council who I know records all known raptors nests. This nest was new to him although he did have a report on file from 2019 that in hindsight could have indicated breeding in the area. The nest was above what looks to be a well used fire place and was sandwiched between two paths which must be used by hundreds if not thousands of people every day. Why the hawks would choose to nest here is a bit of a mystery to me but proximity to lots of prey (pigeons and crows) may be a factor.

I discovered the nest due to the calls of the young which were audible many hundreds of metres away and which also makes the fact that the nest had not been discovered (reported) previously very surprising. When I first discovered the nest I could see there was a single half grown youngster and within two weeks (by end of June) the young were standing on branches by the nest. I only ever saw three young with certainty but there would appear to have been four which is very good going! The young remained in the area around the nest for over a month after they had first clambered out of the nest and made so much noise that I could see that the more observant passers by noticed them but it was still amazing how many people seemed completely oblivious to these large birds which were often just metres from the path and making a heck of a noise!

Finding this pair so close to people was very interesting but what most fascinated me was seeing what they were eating. The young stayed close to the nest begging loudly for food for around a month (much longer than I have noted at the nests in Maridalen) and although I never witnessed a food delivery I heard a couple of times that it was happening and saw the aftermath. The adults would bring in food and it looked as though it was dropped in a couple of areas as these had lots of remains. Hooded Crows were clearly a popular (or perhaps easily obtained) food item but the real surprise was seeing that three Sparrowhawk nestlings had been delivered! I found the remains of two on the ground one of which was just the legs left whilst the other had only been just started on and my pictures and video of a youngster tearing into something show that that was also a Sparrowhawk. I assume all had come from the same nest but wonder whether they were taken in one go or if the adult returned again and again to the nest. I posted a video of this on Twitter and then was shared lots of other videos of Goshawks raiding nests of much larger birds including Ospreys https://www.youtube.com/watch?v=TugfA0c1Ep8 and Booted Eagles https://www.youtube.com/watch?v=cyroMtoKvCg

And read this very interesting Twitter thread from Alex Lees https://mobile.twitter.com/alexander_lees/status/1414543954922680320

During the course of the winter I will write about the two remaining scarce breeders: Honey Buzzard and Great Grey Owl so don't change channel 😀

the Goshawk (hønsehauk) nest when I discovered it

a downy youngster

13 days later and the young whilst not full grown have lost their down and clambered out of the nest

the bird on the right is still in the nest

another 9 days and the young are still close to the nest but are flying around

another week gone but the young are still in the same area around the nest and are very noisy and are not bothered by humans

here a youngster is eating a juvenile (nestling) Sparrowhawk (spurvehauk) which can also be seen in the following video

and here the remains of a further two Sparrowhawks

this one had hardly been touched

while only the legs were left on this one

a close up of the larger corpse showing the bill but the flesh around it had been eaten

the next day there were just feathers and the odd leg left. Whether this was all the work of the Goshawks or if animals had also helped out is unknown

 

a Hooded Crows (kråke) leg which appeared to be the commonest prey item delivered to the young

this youngster was still around the nest and calling nearly 2 months after the first birds had clambered out of the nest