Month: June 2019

When no news is good news

Had this been a normal year at St Georges now would be the time we would be watching the chicks make their first tentative, uncertain, often downright dangerous forays into the air. A time of anticipation, excitement and no small amount of trepidation.  Across the country there are Peregrine broods at various stages of development, a few, such as the Cromer chicks are still white and fluffy, the Norwich brood are properly fledged but most of the urban monitored sites have chicks just starting to fledge in the last week – such as the Wakefield pair, where the genes of Sheffield Peregrines live on.  Pop over to their website and Twitter feed to follow their misadventures!

Once the chicks master their aerial skills and can feed themselves they are off on their own and little is known of what happens to them as they disperse from the natal territory but news did come in last week about one of the previous Sheffield youngsters….

Several weeks ago a dead bird had been seen on the roof of a building in Netherthorpe and was reportedly of a Peregrine.  Not the best news given that we have a missing, displaced female Peregrine however we’ve had false alarms before.  Besides not much could be done without photos and a precise location.  News filtered through to two helpful chaps at the council buildings maintenance office, John and Sean, and they arranged for the bird to be recovered.  The bird was indeed a Peregrine.  It had been dead a good while and in a very decayed and mummified state but was still identifiable as a sub-adult peregrine bearing the orange leg ring ‘PRF.’  Sadly this identifies the bird as one of our 3 male 2017 fledglings.

May 18 ringing PRF

PRF being ringed in 2017

This is the first we’ve heard any of the 2017 brood and perhaps on the face of it confirms the old wisdom that no news is good news.  It is with sadness that the first news received about them is bad news but perhaps not unexpected.  The measure of breeding success for any bird species is getting chicks not just to fledge but to get them to breeding age and condition so that they may have offspring of their own and keep the population stable.  Such rates of success in birds of prey vary greatly from species to species but are all quite low when viewed as a percentage of chicks hatched, and are lower than the success rates you may witness from the small birds nesting in your garden.  Small birds will all breed the year after they are born whereas birds of prey take several years to reach maturity, a figure which varies species to species and to some extent from bird to bird but generally the bigger the bird, the longer the road to adulthood.  We can perhaps think of PRF as a having made it to his “teenage” period before his unknown and as yet unexplained end, not far from his place of birth.

The state of decay means that not much can be deduced about his life or death at this stage, there are no obvious signs, but an examination will take place in due course to find out what we can.  He’d obviously been dead for a while but it would appear he lived for perhaps 12 -18 months.  Perhaps he struggled to master hunting adequately?  Collided with something? Was attacked by another bird?  Something else?  There are numerous possibilities and it may not ever be possible to tell given the state of the bird.  For now he is in safe storage at the university and anything learnt will be disclosed here, as and when.  Thank you to Sean, John and colleagues at the council for getting in touch, recovering the bird and passing it on.  They didn’t have to do this and it is very helpful.  It is only with the help and cooperation of ordinary people that we learn more about the birds and have Sheffield Peregrines as a success story.

So not good news but useful news nevertheless.  We have heard back from very few of the fledged birds from St. Georges down the years. As we know a 2014 bird is the breeding male at Wakefield, one of 2016s offspring was found dead 55km away in West Yorkshire as a two year old bird – death unexplained, one of the 2018 chicks was spotted hanging around the Dearne Valley earlier this year as previously reported… and now the deceased PRF.  All birds identified via their rings which shows the value of ringing the birds….  without ringing we would have no idea that any of these birds were Sheffield born Peregrines.  Or looking at it another way, without ringing we would not be able to confirm that the dead bird is not the ousted female as some have speculated and so, as far as we know, she is still out there somewhere.  Which is good news of sorts.

The last photos of Orange PRF, with thanks to Sean.

 

CG 19/6/19

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June 2019 Update

Last time we updated you a month ago there were still ongoing ructions around the nest as the resident male Peregrine and the “new” female (formerly known as “the intruder”) continued to show their dislike and mistrust of one another.    In the intervening period the two birds started to first tolerate and then accept one another to the point where regular bonding could be seen in and around the nest platform.  Further evidence of their establishment as a pair could be inferred by the broody nesting behaviour displayed by the  female, her scraping out of nest depressions characteristic of that we usually see in March just before eggs are laid.  All this augers well for the continuance of breeding at St. Georges, if these two birds stay together then it may well be business as usual nest spring.  The birds have certainly been very faithful to the platform and perhaps have stayed around longer than we might have expected without chicks to rear.  It’s a long time between now and the next breeding season and anything could happen in the intervening period but there’s no doubt that this territory remains occupied. The circle of Peregrine life carries on.

One constant during this period of entente cordiale has of course been the remaining unhatched eggs. Plans are afoot to recover these eggs for examination and analysis at the University of Sheffield Dept of Animal & Plant Sciences as has happened in previous years to any unhatched eggs.

Although the nest has been deemed a failure this year it is still subject to the laws which protect Schedule 1 bird species from disturbance during the breeding season and, as the breeding season is still officially ongoing, the recovery must be done under licence by a trained and permitted person.  Plus there’s rope access to arrange and the accompanying H&S protocols, all to be performed by volunteers in their own time.  Once arrangements are made it is hoped we will be able to share a guest blog here from the team who will be doing the lab work on the recovered eggs, with a further blog later in the year once the results of the egg analysis are known.  Watch this space!

 

There will also be a further blog post here in the next few days regarding other Sheffield Peregrine related news…

Keep Watching.