Sunday, 14 December 2014

TRUMPETER SWANS in Suffolk and a review of their status in UK
























This pair of TRUMPETER SWANS were discovered at Boyton Marshes in Suffolk yesterday (13 December 2014) and were still present today keeping to the edge of a 70-strong herd of Mute Swans. Both birds were unringed, with one showing traces of orange iron ore on its head - a feature often associated with recently-arrived Whooper Swans from Iceland. They have also arrived following a particularly deep Atlantic low from North America and Canada that crossed the northern isles of Scotland.

These two birds follow a number of records of this species in Britain, most notably the following -:

1) An adult was at Keyhaven Marshes (Hampshire) on 25 February 2001 before moving to the nearby Test Valley at Horsebridge on 19 April. It then relocated to Stocksbridge Water Meadows, where it remained until 27 April.

2) A pair visited Bowling Green Marsh RSPB, Topsham (South Devon) on 15-18 February and 3-10 March 2005. A single adult then moved to Apex Pit, Highbridge (Somerset) from 31 March 2005 to 19 February 2006, with a further adult present in Somerset from 21 January 2006 until the present day.

In Northamptonshire, about a dozen escaped from a private wildfowl collection at Apethorpe Hall in late 1989, the birds although pinioned travelling down the River Nene to Willow Brook. They were seen at Yarwell in March 1990 and at Tansor GP, where 2-3 adults remained until 21 April 1999. They bred in 1997, successfully rearing a single cygnet - thus far, the only such breeding of this species in the UK. Tansor GP then became a private fishery with all monthly WeBS counts ceasing (many thanks to Bob Bullock and Mike Alibone for this information).

At least 27 others have been recorded but generally as escapes from neighbouring collections, several of them private. At one time, they were passing hands at £2,500 per pair but more recently, prices have dropped and as little as £450 can now secure a pair.

According to the US Fish and Wildlife Service, the Trumpeter Swan's historic breeding range extended in a wide band from the Bering Sea east through almost all of Canada and south to Missouri, Illinois and Indiana. However, hunting pressures and habitat loss early in the 20th Century pushed the dwindling population almost to the brink of extinction. With the arrival of European people to the United States, Trumpeter Swan feathers, quills, down and skins were quickly commodified, being used for everything from the manufacturing of pens to powder puffs and bedding. By 1932, the US population outside of Alaska was estimated to number just 69 birds.

Today, the central Alaskan population numbers some 15,000 birds and winters from southeastern Alaska along coastal British Columbia south to the mouth of the Columbia River on the southern border of Washington State. Although migratory, this population is relatively short-distant in movement. Away from Alaska, Trumpeter Swans are found in mixed migratory/non-migratory populations across the Great Basin region of Alberta, Washington, Oregon, Nevada, Wyoming, South Dakota and Minnesota (known as the Interior population) while a further 2,000 or more reside in Canada. A most recent population survey suggested 1,469 individuals in the Interior in September 1997.

Over the last decade, various reintroduction programmes have been initiated along the East Coast, centred primarily around the Great Lakes region. As many as 800 birds are now established in the southern part of Ontario but their movements are largely sedentary or short-distance.

The 2010 Census

A comprehensive count took place in the summer of 2010 resulting with the Central, Mississippi and Atlantic Flyways achieving respective totals of 9,809 and 9,236 individuals, increases of up to 111% on 2005 figures. Of the 9,809 birds counted, 7,154 were adult and 2,655 sub-adult.

Trumpetings online www.trumpeterswansociety.org

The Trumpeter Swan restoration programme in Ontario http://www.bconnex.net/~smorel/trumpet/trumpeter1999.html

Ohio's Trumpeter Swan Restoration Project - first year's summary
http://www.taiga.net/swans/publications/16th_conf/16th_conf_toc.html


Migration Trumpeter Swans Induced http://www.bconnex.net/~smorel/trumpet/induce.html

Wednesday, 26 November 2014

The first ISABELLINE WHEATEAR for County Durham and Cleveland and the identification of late autumn first-winters




A 'wheatear' was first seen on the beach at Seaton Snook (County Durham/Cleveland) by a novice birdwatcher on Saturday 22 November 2014 but after it was subsequently seen next day by local guy Gary Flakes (who sensibly tweeted as such on his twitter feed), top county birders Chris Bell and Tom Francis visited the site expecting to find a Desert Wheatear. What they both didn't expect to find was they they were faced with a very pallid, long-legged, long-billed and staunchly upright individual - very quickly confirmed as County Durham's first-ever ISABELLINE WHEATEAR!!

The bird was showing exceptionally well on the sandy beach, either side of the end of Zinc Works Road in Seaton Carew, and remained on view until dusk on the Sunday allowing some 25 or so local birders to connect. Despite a clear and frosty night, it survived until next day and was still present on Wednesday 26th when I finally decided to make the pilgrimage.

Being a first-winter, the bird was surprisingly 'warm' for an Isabelline Wheatear, being tinged with warm buff in the flanks, and quite sullied on the underparts with some colour on the supercilium. Such individuals are quite tricky but this bird can be safely distinguished from Northern Wheatear on a number of characters, most noticeably the black alula feathers contrasting with the much paler upper wing coverts and rest of the wing, the broad black tail band, the long, pointed bill and in flight, the pale underwing. Supplementary characters include the thin supercilia extending behind the eye, the broad, dark, well-defined loral area, the pale ear-covert patch and the lankier appearance.

Additionally, often considered diagnostic (eg, by Lars Svensson & Keith Vinicombe) is the relative position of the primary tips - the wing tip of both species being formed by P3 and P4, which are similar in length. On the closed wing on Northern, the spaces between the primary tips at rest gradually become wider towards the wing-tip, with the space between P5 and P6 and P4 and P5 being similar in length (and quite long). On Isabelline, however, and illustrated in some of my images that follow, the space between P5 and P6 is distinctly LONGER than the space between P4 and P5.