Monday, 16 December 2013
Ringing return and a case of cannibalism
I was recently contacted by Jacob O'Neil who is a professional Falconer and trainee ringer who, whilst undertaking a visit to Watford came across not 1 but 2 juvenile/immature peregrines.
Furthermore he also managed to get some photos of both birds and after observing behaviour thinks they may be in the early stages of bonding looking like Tiercel and Falcon going on size difference.
Thanks go to him for contacting me.
It is unusual that at this early age they appear to have come together, I know that they are not from the same brood as one is showing a green ring and is likely one of the brood from London that John Black from NaturalEngland and I ringed on May 20th.
With Jacob’s photo I can see a green ring with white numerals; I know Sussex use green but if I remember correctly they use black numerals?
Hopefully this is correct, if so it is a London bird and came from a brood of 4, 2 males and 2 females, the trick now is sexing it and identifying which male or female it is, it’s hard to tell from the photo but it has the look of a female. Jacob had similar thoughts as well after seeing the 2 birds together, if this is the case it should be either ‘AL or AJ’.
Hopefully id can be confirmed but it is a good story as I always wonder where they end up, or indeed if they survive there first winter, whatever happens this juvenile has made a good start.
This rather sadly concerns a juvenile from the same brood and is not such a good news story, although it is nature and as such you can’t label it as horrific, it is sad, prey is taken daily although cannibalism it seems is a rare event.
The following owes much these days to the density of peregrines in and around London, prime sites are contested and it seems that prime foraging areas with plentiful prey species are being contested as well.
I am referring to Rainham RSPB and concerns an adult Falcon taking and eating a male juvenile which was witnessed by 2 independent observers whom I know well.
Below is the account of David Smith who observed it through a telescope relatively closely.
Whilst birding at Rainham Marshes yesterday morning [9/12/13] at about
nine o'clock I noticed an adult female Peregrine sitting on top of one
of the pylons that they regularly use. When I picked it up in my scope I saw
that she was feeding on a bird most of it had already been eaten but one
leg and part of one wing were still left, on closer inspection I was surprised
to see that the leg looked very much like a Peregrines leg that had
a green ring on it I couldn't tell if it was left or right as I was watching
the leg came loose from the rest of the carcase and fell to the ground
after watching for ten minutes the bird flew off in a northerly direction
with the remains of its prey. I walked round to the base of the pylon 
to look for the fallen leg but the vegetation was quite thick and I couldn't
Since then I have visited to search for the leg also to see which male juvenile it was, it was either ‘AD or AN’ but as Dave says the vegetation is horrendous and it must have gone through and is unlikely to be found. Added to this, Foxes, Mice and Rats and its probably gone unfortunately.
What is unusual is the direction she left and also the fact that she took the prey with her, I am presuming she was going to her ‘core’ site to stash the remains. If that’s the case she is not territorial on site but it could be that the Reserve is on the very fringe of her territory and overlaps with 2 other pairs who also regularly use it.
I can’t see the mother of the juvenile taking and eating her own young even if it was long gone, I know they do recognise their own young, even the following year having witnessed it with other pairs.Allthough not welcomed back with open arms they are loosely tolerated by some pairings.
In regard to the 2nd pair that also use the site, if it was the Falcon from there, she would have flown in a different direction to stash the prey, knowing the nest site locations helps a lot, she’s not going to stash it anywhere where Crows can get at it.
It all points to a new female which is using the site and coming in from another direction, she is now being seen pretty regular on site and as yet I don’t know if she has a mate. If you recollect the old pairing succumbed, the Tiercel was killed flying into a fence and a little while later the Falcon disappeared.
Whatever scenario fits it is an unusual occurrence that may have started off as the juvenile possibly flirted or tried to bond with her even if it is early days, it could be that she saw him off and somewhere along the line it became deadly and she saw him as prey.
As we know they don't take carrion so I would have to presume she indeed took the little chap herself.