Ringing: February 2015
Friday 27th February
A very quiet day with just 9 new birds – 8 Starlings and 1 Great Tit, plus 11 re-traps.
DON’T FORGET – YOU CAN CLICK ON THE PHOTOGRAPHS TO ENLARGE THEM.
Wednesday 25th February
Rain early on meant that we did not set the nets up until 10am, however we had a good ringing day and did not eventually finish until 5.30pm, having processed 58 birds, 26 new and 32 re-traps.
New birds were 8 Starlings, 5 Fieldfares, 4 Chaffinches, 3 Greenfinches, 1 Wren, Robin, Mistle Thrush and House Sparrow. This was a good catch of Fieldfares which we don’t get to grips with very often and most of the ringers were pleased to get to process these lovely
birds on the day. Unexpected were 2 Mistle Thrushes, probably a pair – the female was new and was starting to show a brood patch and the male had been ringed previously.
We also had a re-trap Sparrowhawk that had only been ringed a few weeks previously and a female Reed Bunting that had been initially ringed as a 5F on 24th February 2011. This means that she hatched in the spring/summer of 2010 and is now 5 years old. The male Sparrowhawk was hunting Reed Buntings so she must keep her head down to beat the BTO record longevity for this species of 9 years.
MISTLE THRUSHES are by far the largest of the thrushes and are very early nesters, which is why today’s female has already moulted off some of the feathers on her underside to produce a bare patch of skin, with a patchwork of blood vessels, called a ‘brood patch’. This will enable her to efficiently incubate, transferring body heat directly onto the entire clutch of 4-5 eggs.
They are usually double-brooded – the eggs hatch after only 13-14 days and young leave the nest, just able to fly, at a staggering 14-16 days. This amazing rate of growth and development is typical of all passerines. Look out for the pale young birds, once they have become independent and when they can often be encountered, gathering in small noisy flocks in late spring and summer, showing off their tell-tale exaggerated upright stance.
Males have been singing their strident, far-carrying song since before Christmas, proclaiming their territories and attracting females from the highest trees, and the male caught today is possibly the bird that we have heard for some time around the Observatory.
There has been a breeding population decline since the 1970s and the British population now stands at 160,000 pairs. The Mistle Thrush is a mostly sedentary species with some northern birds moving south in the autumn.
Sunday 22nd February
19 new birds: 7 Starlings, 6 Chaffinches, 2 Mallards, 1 Reed Bunting, 1 Great Tit, 1 Robin and 1 Greenfinch.
Wednesday 18th February
A fine, warm day with 59 birds processed and 33 new birds: 9 Starlings, 7 Chaffinches, 4 House Sparrows, 4 Greenfinches, 2 Redwings, 2 Goldfinches, 1 Robin, Blue Tit, Great Tit, Reed Bunting and Blackbird.
Once again Starlings feature heavily, with large flocks around the Observatory, sometimes creating interest for a local Sparrowhawk. Birds are getting ready for the breeding season in many ways as we are hearing regular song from many species and many are moving into their breeding plumage and sometimes showing bright colours.
Male Starlings are looking literally brilliant at the moment, with green, blue and purple iridescence showing on their contour feathers and wing coverts and with bright yellow bill and pale blue base, plus their chattering, whistling, clicking song they must be irresistible to the females. They are very easy for us to sex now as the female has a pink/buff base to her
yellow bill in contrast to the male with his blue bill base (easy to remember – ‘blue for boys and pink for girls’). The male also has a dark iris and the female’s is pale and the long and the elongated feathers on the throat are extremely long and glossy on the male. The two birds photographed together today show all of these features perfectly.
At the end of the winter it becomes increasingly difficult to determine the age of some species as the young birds have moulted even more feathers into their adult plumage and some feather detail is lost due to wear. If all adult Starlings had tails as clear as the one in the photograph, we would have no problems. The wide and obvious fawn edging to each of the broad tail feathers and the broad black pattern curling into a point is diagnostic of this bird being an adult.
Sunday 15th February
A good day’s ringing with 38 birds processed including 26 new birds. 11 Starlings, 4 Chaffinches, 3 Long-tailed Tits, 2 Great Tits, 2 Fieldfares, 1 Reed Bunting, Goldfinch, House Sparrow and Greenfinch.
We have done well with Fieldfares over the last few weeks. Fieldfares are widespread throughout Britain in winter with an estimated population of 680,000 birds. Ring recoveries show that our winter birds mostly come from Scandinavia and Finland, with the majority from Norway and that they do not usually return to the same areas each year, but with around 20% that do so.
Although we think of Fieldfares feeding on crops of winter berries along hedgerows and gardens, a major source of food is also the earthworms and many invertebrates that they glean from grassland and some agriculture. Further inland in the County huge flocks make for apple orchards, where windfall and un-harvested crops can litter the ground for months. This year has been fairly mild with the ground freezing for only short periods, which is why we are seeing them in our area taking an abundance of earth worms and invertebrates. Although they feed on the ground they always fly noisily, making their ‘chack-chack’ calls and up into the tops of the highest nearby trees in order to digest their meals.
Saturday 14th February
A lovely sunny day for maintenance and a lot was achieved once again with the added assistance of a chain-saw. The last work party of the winter will be next Saturday after which ringing will benefit and the reserve’s plants should flourish. A bonus at the end of the day for some was a Black-headed Gull caught in the crow trap.
Although large numbers of Black-headed Gulls winter around our coasts, many also spend the winter inland with huge roosts recorded on some reservoirs and large flocks feeding on pasture, playing fields and agriculture, the latter benefitting particularly from the sudden glut of invertebrate food exposed briefly during autumn and spring ploughing.
Friday 13th February
No ringing today due to strong winds and rain. Vida’s homemade ginger crunch was delicious however.
Wednesday 11th February
Just 13 new birds today with 42 re-traps. 3 Starlings, 2 Goldfinches, 2 Blue Tits, 1 Collared Dove, Dunnock, Robin, Chaffinch, Greenfinch and Reed Bunting.
Tuesday 10th February
51 birds processed with 28 ringed. New birds were 7 Starlings, 5 Chaffinches, 4 Goldfinches, 3 Fieldfares, 2 Blackbirds, 2 Reed Buntings and 1 Robin, Redwing, Great Tit and Yellowhammer. The more unusual birds for us were Fieldfare, Redwing and Yellowhammer.
Yellowhammer is another farmland species declining due to the increasing intensity of cereal production. The reduction in winter food availability and a decline in springtime invertebrates would be the major factors leading to poor breeding success and low survival rates. We are fortunate to still see fairly reasonable populations of breeding and winter populations of Yellowhammers, which have almost disappeared from other parts of Kent.
Monday 9th February
A much busier day with 51 birds processed – 19 new birds and 32 re-traps. One of the Goldfinches re-trapped was not one of ours but a control of a bird ringed elsewhere in Britain. Once our details are submitted to the BTO we will eventually receive details of where it is from.
New birds were 12 Starlings, 1 Stock Dove, 1 Reed Bunting, 1 Great Tit, 1 Chaffinch, 1 Yellowhammer, 1 Fieldfare and 1 Corn Bunting. The Fieldfare and Corn Bunting were new for the year so with the control and some birds that we only occasionally handle, this was an interesting day.
Corn Buntings are highly sedentary birds with a very fragmented distribution and we are fortunate that we have a small population around us here throughout the year, although we rarely catch them. This is a species whose numbers have fallen dramatically over recent years with agricultural intensification and their breeding population in Britain now stands at only 11,000 pairs. The population declined by 90% between 1970 and 2010, and we have seen a contraction of their winter range by 27% since the BTO 1981/84 Winter Atlas. During this time they have ceased to breed in Ireland.
Their fragmented distribution shows clusters on chalk soils from Dorset to Cambridgeshire, on the coast from Kent to Suffolk and on low-lying arable farmland from the Fens north to Durham. Causes for this severe decline are probably down to many factors, but they would certainly include the switch from spring to autumn sowing of cereals which has reduced the winter availability of weed-rich stubble, while the changes in cropping could have reduced the number of birds raising a second brood and productivity will have been affected by the intensity of pesticide use.
Corn Buntings generally form flocks outside the breeding season and feed on the ground very often on the seeds of cereals. In spring and summer they will take invertebrates. The female constructs the nest which is situated on the ground in usually quite thick grass or plants and she mostly feeds the young with some help from the male who spends a great deal of his day singing his jangling song from an exposed perch. Great to watch is his aerial display on slow hovering wings and when he descends he dangles his long orange/pink legs and feet in an exaggerated performance.
Sunday 8th February
21 birds processed today – 9 new and 12 re-traps. New birds were 2 Starlings, 2 Chaffinches, 2 Goldfinches, 2 Reed buntings and 1 Dunnock.
Wednesday 4th February
22 birds processed today – 7 new and 15 re-traps. New birds were 2 Starlings, 2 Reed buntings, 1 Robin, 1 Great Tit and 1 Chaffinch.
Monday 2nd February
11 new birds and 42 re-traps today and the first Monday ringing back in the Whitehouse for quite a while.
New birds: 1 Collared Dove, 2 Blackbirds, 2 Starlings, 1 House Sparrow, 2 Chaffinches, 1 Greenfinch, 1 Goldfinch, 1 Yellowhammer.
Re-traps included varying numbers of Dunnock, Robin, Blackbird, Blue Tit, Great Tit, Starling, House Sparrow, Chaffinch, Greenfinch and Yellowhammer.
The House Sparrow is a very widespread breeding species in Britain and Ireland with an estimated population of
5.1M pairs. This may seem difficult to believe considering the well-known rapid decline of 69% in this species between 1977 and 2010. Numbers seem to have stabilised in recent years and the species may also be increasing. This seems to be borne out by the regularity and apparent increase in birds ringed at The Observatory.
Populations of House Sparrows were affected in both rural and urban situations. Low first year survival rates, connected with reduction in winter food supply caused by agricultural intensification, are probably key factors affecting rural populations. In towns and cities, reduced breeding performance has probably been more important, owing to reductions in the availability of invertebrate prey, air pollution and lack of nest sites as building techniques change and ‘old-style’ buildings disappear.