I completed my last ringing session of the winter in April. Despite the excessively wet and windy conditions over the winter period, I managed six mist-netting sessions at Woeful Lake Farm and a further session at Stones Farm. The site at Woeful Lake Farm consists of arable fields with a large area of cover crop and mature hedgerows. The site at Stones Farm is an old quarry surrounded by arable fields with grassy field margins and mature hedgerows. The quarry has a sheltered grassy area surrounded by scrubby bushes and trees. Both sites have been fed with seed throughout the winter. The site at Stones Farm has very good numbers of Yellowhammer, Linnet and Reed Bunting and looks to be a promising addition to the project next winter.
The table below summarises the birds caught for the first time and those recaptured throughout the winter period.
|Great Spotted Woodpecker
The numbers of Linnet and Yellowhammer caught increased towards the end of the winter. This is because natural food supplies diminish as winter progresses and birds gather at areas where food remains – in this case where we provided supplementary seed. The relatively warm winter this year may have reduced the size of winter flocks – although there was a flock of up to 80 Linnet using the site this year, this is considerably smaller than the flock of several hundred present in previous years.
Examination in the hand revealed that the Yellowhammers and Linnets caught were a relatively even mixture of adult birds and first year birds (i.e. birds born in the 2015 breeding season). Previous studies and ringing recoveries have shown Yellowhammers in particular to be sedentary, with similar breeding and winter distributions and few long distances movements of birds. The capture of first year birds therefore indicates that Yellowhammers have bred successfully in the area last year and in the future it should be possible to look at changes in the proportion of adults to first year birds as an indicator of changes in breeding success.
To date I have only had one recovery of a ringed bird by a third party. A Great Tit ringed in December was recaptured by another bird ringer in Sibford Ferris (Oxfordshire) on 31 March 2016, a movement of 31km. It is unusual for a Great Tit to move as far as this but first year birds, such as this one, are known to be more likely to disperse than adults.
A more detailed report of the project so far can be found in the NCOS newsletter, and please continue to look out for colour ringed Corn Bunting (yellow with black characters) and Yellowhammer (dark blue with white characters) on the Sherborne Park Estate.
Turtle Dove Richard Tyler
This Saturday (16th April) sees the African Bird Club AGM at the Natural History Museum in London. There are half-a-dozen associated talks, and the event is open to members and non-members alike.
Of particular interest to us here in the Cotswolds is a talk on Turtle Doves in their wintering grounds in Senegal by Niki Williamson. Fewer and fewer of these birds visit the UK in summer. They are now scarcely seen in Gloucestershire and no longer breed in the county at all.
Curlew Richard Tyler
And closer to home, don’t forget our own AGM this Weds (13th April) at the Farmers Arms, Guiting Power at 7:30. Our guest speaker is Mike Smart, the county’s previous BTO rep, on ‘The Decline of the Curlew’ – very topical with members of the Society involved in the RSPB Curlew survey at the moment.
Last autumn, NCOS kindly provided me with a grant to help set up a farmland bird ringing project on the National Trust’s Sherborne Park Estate. The Estate has good numbers of farmland birds present in both the breeding season and over-winter, including red-listed species such as Corn Bunting Emberiza calandra, Yellowhammer Emberiza citronella, Linnet Carduelis cannabina and Skylark Alauda arvensis. The project’s aim is to increase understanding of population changes and local movements of farmland bird species over the medium term to help us make conservation management plans for the Estate. I hope to achieve this by a combination of regular winter ringing sessions and nest monitoring in the breeding season.
Ringing birds is very weather dependant as mist nets cannot be used in windy or wet conditions and so there have been limited opportunities to get out so far this winter. However, I have fed the site since October and managed a number of short sessions, which have proved useful to observe bird behaviour and optimise catching methods. A flock of up to 100 Linnet has been building, and good numbers of Chaffinch Fringilla coelebs with smaller numbers of Greenfinch Chloris chloris, Goldfinch Carduelis carduelisi, Reed Bunting Emberiza schoeniclus and Yellowhammer have also been present, and I have so far ringed a number of these species as well as commoner generalist species. As winter progresses and natural food supplies diminish, I hope numbers will build further.
To maximise the data obtained by the project I will be colour-ringing any Corn Bunting and Yellowhammer caught, as both species perch prominently in the breeding season and so should be easy to re-sight. If any NCOS members are out walking on the Sherborne Park Estate, please check these species for colour rings and report them to CotswoldsCR@outlook.com. Corn Bunting colour rings are placed on the left leg and are yellow with one letter and two numbers engraved in black. Yellowhammer colour rings are also placed on the left leg and are dark blue with two letters engraved in white.
Peregrine and young – Dave Pearce
The Painswick Bird Club is one of the smaller wildlife groups in Gloucestershire. Possibly they are squeezed for membership by the Cheltenham Bird Club to their north and Dursley Birdwatching and Preservation Society not far to the south. They have some interesting talks, though, and guests are welcome there at the Painswick Town Hall.
Last night Steve Watson of the Gloucestershire Raptor Monitoring Group and South West Peregrine Group gave a lively and intriguing talk on Peregrines. Steve is a long-standing (obsessive?!) Peregrine watcher with a fascination for their physiology: just how does this bird manage its high-speed stoops and the huge G-forces when it manoeuvres? How does it focus on its prey, near or far? And what weaponry has it evolved?
Steve’s observations centre on the RSPB site at Symonds Yat. This is a sheer cliff face in the Forest of Dean where you can see great views of the birds in flight, and Steve showed some video clips of this. To complement this, he invited Dave Pearce to say a few words about the Christ Church Peregrines at Cheltenham. The footage Dave has is more restricted but more detailed, with egg-laying and nest behaviour more in evidence that flight.
(The title for this piece became obvious once Steve mentioned that aPeregrine had been seen near Painswick church tower, which is just across the road from the Falcon Inn and the bowling club of that name!)
New Bridge Lane
We have an outdoor meeting at Bourton-on-the-Water gravel pits this Sunday. The winter wildfowl are beginning to come in, and the Red Kite are increasing. Meet up at the Rissington Road lay-by at 9a.m. We’ll probably have a look at the marshland near New Bridge Lane as well (see photo). Likely to be muddy.
There are also a couple of good indoor meetings in the area (or in Gloucestershire at least). Most, I think, are a couple of pounds for non-members.
On Thurs 5th November Painswick Bird Club host a joint meeting with the Gloucestershire Naturalists Society at Painswick Town Hall (7:30). Jim Almond the wildlife photographer talks about Bird Reserves of the north Norfolk coast – a hot-spot if ever there was one.
On Fri 13th November Gloucestershire Naturalists Society’s speaker is Chris Sperring MBE (Hawk and Owl Trust) on British Owls, their natural history and conservation. This is at Watermoor church hall (no.4 on map), Cirencester at 7:30.
The next day members of Gloucestershire Wildlife Trust hold their AGM at the University of Gloucestershire (Park Campus) in Cheltenham. Adam Hart, Professor of Science Communication is the keynote speaker there.
We also have an indoor meeting at the Farmers Arms, Guiting Power on Fri 27th November for a skittles evening.
Barn Owls at six-and-a-half weeks
On last month’s expedition to ring a brood of Barn Owls we found another barn containing a nest-box that no-one had been aware of. Closer inspection revealed three newly-hatched chicks. As they were reckoned to be about one, three and five days old, they were too young to be ringed that day.
We came back nearly six weeks later and found an adult (which immediately slipped away) and two well-grown chicks. Don’t ask what had happened to the third…
A. ringing the elder one
D. retrieving the chicks in cotton bags
These chicks were slightly less advanced than the other brood when we ringed them – see how much down they still have compared to these.
M. who was supervising (Barn Owl ringing needs a Schedule 1 endorsement to the ringing permit) looked up the wing measurements in the tables, and pronounced the birds to be between 44 and 46 days old. This agrees very well the estimate of one to five days old when we first found the brood. It also suggests, unsurprisingly, that it was the youngest sibling that did not survive.
Young Barn Owls Tom Beasley Suffolk
After 2014’s massive year for Barn Owl breeding, 2015 has been miserable. M reckons he has inspected 40 boxes in the whole county this year and ringed one single chick!
A retrieving the chicks
Better news, though. A box near Sherborne contained a very young chick and three eggs at the beginning of July.
Several weeks later there were three well-grown young, just past the ‘ugly’ stage and shedding their juvenile down whenever they moved.
Measuring to estimate the age
All three were ringed and measured. Incredibly (to me at least) you can age the chicks pretty accurately by measuring the seventh primary feather’s length and looking it up in guru Colin Shawyer‘s tables.
M weighing a chick in the bag
Weighing was also a surprise – the older the chick, the lighter they are.
They reach their maximum weight in the nest and slim down to flying
weight as they develop.
As the main website can no longer be updated news items will appear here on the Blog.
Normal service will be resumed as soon as we have decided on the new design and content and rebuilt the site.
As some of you may have noticed the website has not been updated this month. Unfortunately (or fortunately – depending on how you look at it) the software that supports the editing has been upgraded and (you knew this was coming didn’t you?) no longer works with the template used to build the site. The site will therefore have to be rebuilt.
The good news is that it should work better on mobile devices (iPhones, iPads and the like*) and we know that we do get visitors who use these.
It also gives us the opportunity to redesign the site – so if there are things you would like to see let us know using the ‘info‘ address.
Any thoughts by the end of September please.
*other computer and communications equipment are availble!)
Hen Harrier – Richard Tyler
Gloucestershire Raptor Monitoring Group is holding a Raptor Id Day on common British birds of prey on Sat 20th June.
It takes place at the International Centre for Birds of Prey, Newent and will include not just info but a chance to see various species flying and close up.
The day costs £15 and numbers are limited, although there are a few places left at time of writing. Booking is via the Glos Raptors online shop.