Friday, 22 November 2013

Up the tower in the sunshine

A quick visit up the tower this afternoon (22nd) in bright sunlight found both adults sitting on the lettering of Jurys Inn. It must be quite a few degrees warmer there than on the east side of the cathedral tower which goes into shade very early in the day in winter. It was also probably more out of the wind too!
South face of Jurys Inn seen from the tower top
with both peregrines just visible as dots on the 'Y' and 'N'
Prey remains were few and far between on this visit. The only thing visible was a headless duck teal on the south side of the tower on top of one of the 'grotesques'. You may just be able to see the speculum on each wing - a small patch of green feathers with white bars above and below them.
View looking vertically down to the pavement and parked cars 200 feet below the tower
The teal is lying on the 'bottom' of the downwards-facing grotesque with its white bars 

on each speculum clearly visible.
This angled view taken by holding the camera out through the bars shows a winged grotesque (the central one of three) in the foreground and the one with the teal beyond. The stonework on this side of the tower is slightly different from that on the east, across which the 'pud' cam looks. The ledge is not so broad as on the east side.
Teal remains just visible on the further grotesque
On the ground below the tower were a few small feathers and one moulted peregrine feather. Peregrine flight and tail feathers are very distinctive as you can see below:

Nick B (DWT)

Friday, 8 November 2013

Fly by night.....and teal and woodcock updates

A quick trip to the top of the tower today (8th November) hoping to find some prey remains looked like being a bit of a wash out (it was raining too by the time I got up there).
There was very little on the roof (someone had been cleaning up I suspect) and also the tops of the 'grotesques' on which the peregrines often sit and leave prey remains were also almost devoid of anything except for the head of a teal - well out of my reach.
However tucked away in the lead spout at the far end of the east side (as seen from the 'pudding' camera that looks across the ledge), there was the corpse of a recently taken wader.
I managed to pull it out and quickly identified it from its size, grey colouring and wing pattern as a knot, a small wading bird.
Left wing of knot showing its wing bar
Knots breed in the arctic but travel south in autumn. British estuaries and bays such as the Wash, Morecambe Bay and the Severn Estuary host thousands of knot (and other arctic waders) during the autumn and winter.
The knot's leg  (tarsus) and foot
This is a common and widespread species occurring in North America as well as Europe and Asia.
In summer the breeding birds turn red underneath which explains their american name - red knot. It's scientific name is Calidris canutus, named after King Canute who famously tried to defy the incoming tide. These waders run along the tide edge and hence the connection.
The link below shows a knot in winter plumage in flight so the wing pattern can be compared:

http://ibc.lynxeds.com/photo/red-knot-calidris-canutus/flight

(More photos and videos of knots can be found at http://ibc.lynxeds.com/species/red-knot-calidris-canutus and on a BBC site at http://www.bbc.co.uk/nature/life/Red_Knot )

The corpse did not smell but wasn't completely fresh so I would guess it was caught the night before last (5th-6th) but obviously I can't be sure. I've not checked to see yet it that ties in with any observations reported to the blog.
Knot are very rarely seen on the ground in Derbyshire and since they migrate at night, I would be confident that this bird flew over Derby after dark perhaps on its way from The Wash to the east to somewhere on the west coast - an easy overnight journey for such a bird. Sadly for the knot, it didn't make it.....
We have recorded knot as prey here at Derby before on eight occasions (this being the ninth) and I recall the species has also been found at Coventry in the West Midlands.
UPDATE 10th November: screenshots taken by Phoebe last night showed a female teal as prey. This small duck is regularly on the menu (except in summer). The photo below shows the green speculum feathers and some of the white bars above and below them:
Pair of wings from a teal found a few years ago at the cathedral
Other prey remains found recently included wood pigeon, woodcock, starling, little grebe, feral pigeon and the knot of course.
Update 12th Nov: a woodcock that had flown into a Derby window and broken its neck was made available to me yesterday. Here are some photos of this beautifully plumaged bird. It is considerably larger than the knot and much heavier too...so more of a meal for a peregrine.
Woodcock - what wonderful plumage!
Unlike knot and other waders, woodcock are entirely nocturnal birds, feeding at night in wet meadows and marshes where they probe for worms with their large straight beaks. Before dawn they fly into woods and settle on the woodland floor, superbly camouflaged among the fallen leaves and the vegetation. Probably something like 100,000 woodcock fly to the UK from Russia, Eastern Europe and Scandinavia to spend the winder with us. Some have been satellite tagged so we know exactly where those birds were breeding.
Many get shot or have accidents while migrating or on arrival here (like this one). A relatively very few are taken by peregrines.
As you can see, woodcock are very dark birds, have no wing bar (unlike the knot) and therefore look quite different when seen on the web cams.
Nick B (DWT)
Ps. The adult male was on the nest ledge when I arrived and the female on Jurys Inn. No sign of a third bird.