Suffolk Birds 1999 Part 1

CO

o

s M

Incorporating

a review of birds in Suffolk in 1999

Brtyöon

West Area Recorder: North-East Area Recorder: Colin Jakes, Richard Waiden, 7 Maltward Avenue, 21 Kilbrack, BURY ST. EDMUNDS, BECCLES IP33 3XN NR349SH Tel: 01284 702215 Tel: 01502 713521 E-mail: cjjakes@supanet.com E-mail: walden1@supanet.com

Watf

South-East Area Recorder: Brian Thompson, 42 Dover Road, IPSWICH IP3 8JQ Tel: 01473 726771 E-mail: brianhilli@aol.com

Gl. Yarmouth

a Frittoti lafca

NORTH-EAST AREA Halas worth

BJythboigh

Southwoid

livarmara

Minsmffre PramNn gham

North Warren I I . A We bui gh

WEST AREA Gippmg Vbí* ySOUTH-EAST

AREA

Woodb'»dg« Orlordn«»!

Ipíwtch R

M»werqaie is«»'»d

StOur

Sudbu'v

Hjidie»?* Raydon IOWC

All'*o Wntrr l«n<l<tii*rr1

SUFFOLK BIRDS VOL. 49 Incorporating a review of birds in Suffolk in 1999

Editor

G Lowe

Published by SUFFOLK NATURALISTS' SOCIETY

2000

1

Published by The Suffolk Naturalists' Society, c/o The Museum, High Street, Ipswich IP1 3QH Š The Suffolk Naturalists' Society 2000 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior permission of the Copyright owners.

The SNS is a Registered Charity No. 206084.

ISSN 0264-5793

Printed by Healeys, Unit 10, The Sterling Complex, Farthing Road, Ipswich, Suffolk IP1 5AP.

2

CONTENTS Page Editorial Gary Lowe Review of the Year Gary Lowe The Caspian Gull in Suffolk Brian Small The Breeding Bird Survey in Suffolk Gary Lowe The 1999 Common Nightingale survey in Suffolk Andy Wilson and Mick Wright Systematic List 1999 Appendix I: Category D species Appendix II: Category E species (escapees) Appendix III: List of non-accepted records List of Contributors Gazetteer Earliest and latest dates of summer migrants Erratum: Orwell WeBS counts 1998 Rarities Report Gary Lowe A Guide to Recording Birds in Suffolk Landguard Bird Observatory, 1999 Michael James Regional Review Gary Lowe Suffolk Ringing Report Tony Hurrell & Mike Marsh

5 6 12 22 26 29 135 135 138 139 140 142 143 144 150 153 158 163

List of Plates Plate No. 1.

2.

3.

4.

5.

Facing Page Barnacle Geese Derek Moore 40 Great White PĂŠlican Derek Moore 40 Sooty Shearwater Andrew Easton 40 41 Eurasian Spoonbill Derek Moore Greater White-fronted Geese Clive Naunton 41

Plate No. 18. Black-headed Gull Alan 19. Little Gull Alan Tate 20. Dingle Marshes Derek 21. Common Wood Pigeon 22. Eurasian Wryneck Alan

Tate Moore Alan Tate Tate

Facing Page 88 88 89 89 104

Greater Scaup Alan Tate Ruddy Duck Alan Tate White-breasted Moorhen Paul Holmes White-tailed Eagle Clive Naunton

48 48 48 49

23.

24.

25.

26.

Pallid Swift Roh Wilson Northern Wheatear Alan Tate Wood Lark Alan Tate Yellow Wagtail Alan Tate

104 104 105 105

10. Peregrine Falcon nest-box Gary Lowe I I . Osprey Derek Moore 12. Northern Lapwing Derek Moore 13. Sanderling Martin Turner 14. Gulls at Sizewell Gary Lowe 15. Yellow-legged Gull Andrew Easton 16. Ruff Alan Tate 17. Ivory Gull Derek Moore

49 49 72

27.

28.

29.

Sedge Warbier Alan Tate Common Starling Derek Moore Pied Flycatcher Alan Tate

105 128 128

72 73 73 73 88

30.

31.

32.

33.

Common Rosefinch Paul Holmes Common Linnet Alan Tate Common Crossbill Alan Tate Eurasian Jay Alan Tate

128 129 129 129

6.

7.

8.

9.

F r o n t cover: Ivory Gull Martin Turner The Copyright remains that of the photographers

3

Notice to Contributors Suffolk Birds is an annual publication of records, notes and papers on all aspects of Suffolk orni thology. Except for records and field descriptions submitted through the county recorders, al material should be original. It should not have been published elsewhere or offered complete or ii part to any other journal.

Authors should carefully study this issue and follow the style of presentation, especially in rela tion to references and tables. Where relevant, nomenclature and order should follow Dr K. H Voous's List of Recent Holarctic Bird Species and use of English names should be as in the BOU's 'Checklist of the Birds of Britain and Ireland' (Sixth Edition, 1992).

If typed, manuscripts should be double-spaced, with wide margins, on one side of the paper only.

They must be in the final form for publication: proofs of longer papers are returned to authors, but alterations must be confined to corrections of printer's errors. The cost of any other alterations may be charged to the author. It is possible for papers to be submitted on computer disk: contact the Editor initially for advice.

Photographs and line drawings are required to complement each issue. Suitable photographs ot birds, preferably taken in Suffolk, should ideally be in the form of 35mm transparencies. A payment of ÂŁ10 will be made to the photographer for each photograph published and ÂŁ5 for each drawing. Every possible effort will be made to take care of the original photographs and artwork.

However, photographers and artists are reminded that neither the Editor nor the SNS can be held responsible in the unlikely event that loss or damage occur.

Authors may wish to illustrate their papers, but this will be subject to the illustrations being of the standard required by the Editor and the decision on such matters will rest with him or her. Material submitted for publication should be sent to the Editor no later than March 1st of each year.

Authors of main papers may request up to five free copies of the journal.

Suffolk Ornithological Records Committee:

Chair: Stuart Ling Area County Recorders: Colin Jakes, Brian Thompson, Richard Waiden.

Secretary: Vacant.

Other Committee Members: Steve Bubbs, John Cawston, Richard Drew, Trevor Kerridge, Gary Lowe, Rob Macklin, David Pearson, Steve Piotrowski, Malcolm Wright.

ADDRESSES Papers, notes, drawings and photographs: The Editor (Suffolk Birds), The Suffolk Naturalists' Society, c/o The Museum, High Street, Ipswich IP1 3QH. Records'. See inside front cover.

Suffolk Ornithological Records Committee - correspondence: The Secretary, SORC, c/o The Museum, High Street. Ipswich IP I 3QH.

4

EDITORIAL As you will see from the cover, the Report for 1998 was judged the best produced that year in the British Birds competition. It is a great honour as the standard of reports is now very high. This would not have been achieved without a lot of work by many people. Usually, the acknowledgements get left until the end of this part of the Report; I think it would be appropriate this year to put them at the beginning. The authors of the sections of the species' accounts are always to be congratulated on their work but this year especially so; continued problems with the computer records meant that the data presented for interpretation to the authors were, in some cases, virtually indecipherable! Despite their valiant efforts, there is the real possibility that some errors have crept in - only time will tell. As usual, this Report would have been much poorer without the invaluable work of Philip Murphy. Thanks also to the three recorders, Dick Walden, Brian Thompson and Colin Jakes. Mike Gaydon at Healeys was as helpful as ever. Thanks also to Steve Piotrowski and John Grant and to Brenda, my partner, for her help and support. Finally, thanks to all those who sent in records, especially the RSPB, SWT, EN staff, the WeBS organisers and those individuals who sent in survey data covering the more common species.

Not wishing to rest on our laurels, this year's Report introduces some further changes. The report on rarities is in a different format. Rather than merely reproducing the submitted descriptions of the discovery and identification of a range of rare birds, it begins with an overview of the year. Selected species are then looked at in more depth. There are also changes in the species' accounts. The categorisation of species now more closely follows the British Ornithologists' Union (BOU) lists, as explained in the introduction to the species' accounts. It is interesting to note the number of species which are included in several categories; for instance, both Chaffinch and European Greenfinch, as well as being recorded as genuinely wild (Category A), have also been recorded as escapees and are, therefore, also in Category E. Other species included in Category E are much more bizarre: a White-fronted Bee-eater Merops bullockoides may just about be understandable but a Snowy Sheathbill Chionis alba?

Other noteworthy features include a comprehensive, nay, ground-breaking paper on Caspian Gull by Brian Small and a paper by Andy Wilson and Mick Wright of the BTO on how Suffolk featured in the national Common Nightingale survey. Back by popular demand after their introduction last year are the review of the year and the look at news from neighbouring counties. On top of that, old favourites such as the Landguard and ringing reports are still there.

Unfortunately, despite all this, the Bird Report still remains incomplete. It is sad to note that both the number of people participating in the Breeding Bird Survey (BBS) and the overall number of observers contributing records are down. This contrasts with the higher sales of last year's Report. One has to assume that anyone reading this Report has an interest in the birds of Suffolk.

If that extends to active birdwatching then you have no excuse for not sending in records and participating in at least the BBS survey. It may be a bother but unless you do, you are letting down everyone else who does and everyone who reads this Report expecting it to be a comprehensive account of the birds in Suffolk in 1999. I am aware of several important records that are going to be lost because the observer has not submitted a description (and in some cases, not even the record!). The Suffolk Ornithological Records Committee (SORC) has again revised the list of species for which descriptions are required (County Rarities). There are now fewer than ever and it is the belief of the Committee that only those species where identification difficulties exist are included. Note that submitting records is now even easier as all the Recorders are on e-mail, as detailed inside the front cover.

Gary Lowe, Boyton.

E-mail: garv.lowe@talk21 .com

5

Suffolk Bird Report

1999

REVIEW of 1999 The year was very wet, the wettest since 1987 in some areas. The spring was warm but raii dominateti in June and the late-summer period. There was a brìef speli ofhot weather in August.

In terms of variety of species, 1999 was a very disappointing year. There were just 263 specie; recorded. This compares with 265 in 1998, 267 in 1997 and a bumper 272 in 1996. Despite thc low total there was a certain quality about some of the birds seen; Pallid Swift, Pallid Harrier ani Ivory Gull were all additions to the Suffolk list and there were also some encouraging breedini reports.

January A soutlì-westerly airstream dominated early in the month bringing mild weather. There fol lowed a brief speli of colder weather mid-month before the warmer weather returned. Tempera tures reached 13C (55F) on January 25th in the south-east of the County and on 20th Wattishan Airfield recorded the wärmest January night for 16 years. The month was snowless and largel) dry. Whilst Suffolk was enjoying unseasonable conditions, much of Scandinavia and parts of Rus sia were experiencing the coldest weather for 100 years. Unfortunately, this did not lead to am weather-related inßuxes of birds.

As usuai, there were high numbers of Red-throated Divers off the coast; over 2300 were counted off Thorpeness on 8th. Several Black-throated Divers were also present, its was a good year for the species with the highest annual total in Suffolk since 1987. It was, however, a pooi year for both Slavonian and Black-necked Grebes, with few reported during the year. High numbers of E u r o p e a n Golden Plovers were on the Blyth Estuary early in the month; 6000 on lsl equals the County's largest recorded gathering. There was something of an influx of E u r o p e a n Shags during the month, staying for the early part of the year, with reports widespread along the coastal strip. There were also good numbers of H o r n e d L a r k s in the County; a flock of 75 on Orfordness was the largest reported since 1973.

Bar-tailed Godwits and Red Knot Peter Beeson

Review of 1999 February It was a month of contrcists as cold and mĂźd weather alternated. The coldest days were 8th and 9th, when snow feil and temperatures only reached 3C (38F). The highest temperatures were reached on 19th when 14C (57F) was recorded, I3F above the long-term average. The month was generally dry. There was afunnel cloud reported at Great Finborough on 7th, an apparently increasing phenomenon in this country.

The main feature of this month was the awesome spectacle of huge numbers of gulls off the coast. Thought to be attraeteci by large shoals of sprats Sprattus sprattus, some of the counts were remarkable: 30000 Black-headed Gulls, 12000 Black-legged Kittiwakes, 12000 Mew Gulls and 300 G r e a t Black-backed Gulls. Remarkably, during the month there were also high numbers of several of these species roosting inland at Lackford WR, such as 2000 Mew Gulls and 180 G r e a t Black-backed Gulls. In addition, several Iceland and Glaucous Gulls were also present along the coast. There were further record counts of Pied Avocets in the Aide/Ore area. A Ring-necked Duck was found on the Orwell Estuary during a WeBS count on 2Ist. March March was a warm month, with temperatures exceeding the average on 21 days. Spring arrived on lOth when temperatures soared to 17C (62F) and daily totals of 10 hours sunshine were reported from several places.

As in recent years, there was a notable passage of C o m m o n Buzzards along the coast. The numbers were well up on previous years with one estimate of 50 birds passing through during the month. A G r e e n - w i n g e d Teal, the North American equivalent of the Common Teal, which has recently been recognised as a separate species, was at Minsmere for part of the month.

Aprii April was sunny and dry. Nearly 230 hours of sunshine were recorded during the month, making Suffolk, along with Essex, the sunniest place in Britain during the month. Measurable rain only feli on nine days during the month. Temperatures exceeded the average on 20 days, the wärmest being 5th when 18C (64F) was reached. Initially, winds were from the south-west, changing to northerly for a period mid-month. A major depression hit the area on 20th, bringing gale force winds and rain.

Perhaps because of the largely settled weather, the passage of waders was very poor; numbers of most species were well down. The weather may also have explained the very early C o m m o n W h i t e t h r o a t at Nunnery Lakes, Thetford, on 8th; the earliest record since 1989. The same day a C o m m o n Cuckoo was reported at Lackford WR. The earliest-ever Artic Tern in Suffolk was seen on 6th and the secondearliest Spotted Flycatcher, on 15th. A White Stork at Blythburgh on 5th was the sole record of that species in the year as was a Black Kite at Minsmere on ^14th. A E u r o p e a n Serin at Landguard was the first of two for the site, the only records in Suffolk during the year. Two C o m m o n C r a n e s were seen in the Minsmere area on two dates, 17th and 27th. A Blackcrowned Night H e r o n was at North Warren from 2Ist to 30th. It was a good year for G r e a t Bittern, with increased numbers at the main breeding sites and others reported elsewhere.

Great

1

Bittern

English Nature

S uffolk Bird Report

1999

May May meant dry and warm weather in 1999 with lots of sunshine and above-average tempera tures on 21 days in the month. An anticyclone gave way to a depression centred on France oi 4th, which resulted in chilly north-easterly winds and torrential rain. Generally, rainfall was be low average for the month. A south-westerly airstream dominated for much of the rest of th> month apart from a period of north-easterly winds in the third week. Temperatures reached 21( (70F) on 19th and a peak for the month of23C (74F) on 28th.

The first of seven Roseate T e r n s during the year was recorded this month, the highest annua total this decade. A T e m m i n c k ' s Stint at Mickle Mere on 15th and 16th was the first inland re cord since 1995. A Terek S a n d p i p e r was at Minsmere on 27th and 28th. The first of five Marsl W a r b l e r s seen in the County during the year was at Landguard on 19th; the same site hosted .

Red-breasted Flycatcher on 19th. An Alpine Swift spent the evening of 28th over Lowestoft On the same day a Hoopoe was at Dunwich, the only record of the year. There were only twi records of E u r a s i a n Wrynecks during the year; one this month inland at Lackford WR and om in September. Several Bohemian Waxwings lingered, one remaining at Kelsale until May 10th The month, though, belonged to raptors: on 8th, a E u r o p e a n Honey-buzzard (the first of eigh: during the year) was seen at Kessingland and a M o n t a g u ' s H a r r i e r was at Westleton Heath; ; Red-footed Falcon was at Minsmere on 27th and, best of all, a Pallid H a r r i e r , the first recordeii in the County, flew over Suffolk WP, Bramford, on 7th.

June June began with a day of unbroken sunshine, light winds and a temperature of20C (68F) but deteriorated rapidly.

A thunderstorm crossed the County on 2nd, followed by a week of showery weather. A shallow but slow moving depression on 7th gave torrential rain and more thunderstorms. Another storm struck on 12th, this time accompanied by abnormally low temperatures; only 15C (59F) in many parts. The remainder of the month was unsettled as depressions came from the south-west. For the third consecutive year the June rainfall total was above-average (in Ipswich the rainfall total was more than double the average). Rain fell on 19 days in the month. Not surprisingly, flooding was widespread in the County.

In a topsy-turvy month, a Bohemian Waxwing remained at Kessingland until 7th, the latest County record and Great Cormorant Ring Ouzels were seen on 13th and 26th. A C o m m o n English Nature Rosefinch, one of three reported during the year, was singing at Walton, Felixstowe, early in the month. The second and final record of the year of M o n t a g u ' s H a r r i e r was a bird at Westleton Heath on June 6th. A P u r p l e H e r o n was at Minsmere from 16th to 20th and a Rosy Starling was at Hollesley on 20th and Trimley St Mary the following day. Good numbers of M a n x Shearwaters seen during the month helped produce a record total for the year. However, most species had settled down to breed and there were some very favourable reports. The first confirmed breeding of C o m m o n Buzzard this century was received; G r e a t Black-backed Gulls bred (unsuccessfully) on Orfordness, the first Suffolk record; N o r t h e r n Pintails bred at a coastal site, the first successful breeding since 1951; D a r t f o r d W a r b l e r s continued their increase both in numbers and sites; the breeding population of G r e a t C o r m o r a n t s grew and both Little and G r e a t Crested Grebes showed some stabilisation in the decline of the breeding populations. A

8

Review of 1999 national survey of C o m m o n Nightingales established that a far higher number than expected bred in Suffolk, enough to rank it second nationally for this species. It was also a good year for Spotted Crakes; five calling maies were reported from three sites, the best breeding data since 1987. In addition, Short-eared Owls bred on Havergate Island, raising three young, the first confirmed breeding in the County since 1987. On the down side, Little T e m s had another disastrous year and reported numbers of breeding Grey Partridges were well down.

Jull The thunderstorms and torrential rain continued for the first week of July; another funnel cloud vi 'as seen, over Saxmundham, on 7th. Thereafter the weather was dominated by anticyclonic conditions and the month was generally wann and sunny apart from strong south-westerly winds on 2 Ist. Rain only feil on nine days and rainfall totals were below average. Temperatures exceeded the long-term average of2ÌC (70F) on 25 days, reaching 28C (82F) on 24th and 30th.

Further encouraging breeding reports included a continued increase in the numbers of Blacklegged Kittiwakes breeding on Sizewell rigs and a further increase in the M e d i t e r r a n e a n Gull population to seven pairs, since the first successful breeding in 1995. There was also a strong possibility that Firecrests bred at a site in the north-east of the County; this would be the first time in Suffolk since 1988. There was a sériés of reports of C o m m o n C r a n e in the west of the County, probably referring to one wandering bird.

August The hot and humid conditions continued into early August. Temperatures generally reached 32C (90F) in the west ofthe County and touched 35C (95F) at Mildenhall. The temperatures triggered vigorous convection and resulted in frequent thunderstorms and downpours of tropical intensity. A south-westerly airflow meant that the remainder of the month was cooler although still affected by storms. Some notably high rainfall totals resulted, such as 141 millimétrés (5-54 inches) in Ipswich, the highestfor the month since 1916. There was short period of northerly to easterly winds around the 25th. Yet another funnel cloud was observed, at Henham on 9th. The solar éclipsé on 1 Ith was partially obscured by thin, high cloud but still visible.

As would be expected the month belonged to waders and seabirds. There was an influx of C u r lew Sandpipers, exemplified by a high count of 50 at Orfordness on 29th. A M a r s h S a n d p i p e r was at Trimley Marshes on 3Ist and there was a good passage of Wood Sandpipers. A Rednecked Phalarope at Liverniere Lake on «2Ist was one of five during the year and only the second inland record of the cenStury. There was the now expected build-up of Little Gull numbers at ¡Benacre Broad ! during the month and the start of a good passage of Long-tailed Skuas, leading to I the second-best jever County anNorthern Fulmar and shearwaters Mark Cornish 9

Suffolk Bird Report 1999 nual total. A Cory's Shearwater, one of two during the year, was off Southwold on 28th.

The peak count of Eurasian Spoonbills for the year was 15 on 29th. There was a brief flurry of passerine interest on 12th, when a Yellow-breasted Bunting was found at Landguard but this was eventually determined to be an escapee. The only Icterine Warbler record of the year was of one ringed in Tunstall Forest on 8th. The first of only three Red-backed Shrikes, ail juvéniles, recorded during the year was at Easton Bavents on 30th, making 1999 the worst-ever year in Suffolk for the species.

September An anti-cyclone centred to the east of Britain resulted in warm conditions at the beginning of the month. The temperature reached 27C (80F), warmer than both the Canary and Balearic Islands at that time. However, the weather broke down from 13th, and fréquent torrential downpours and the occaPallas's W a r h l p r Stuart I ine sionai thunderstorm dominated the rest of the month. Particularly heavy rain around 15th was associated with the tail-end of hurricane Floyd. The corn bined rainfall for August and September exceeded 280 millimétrés (11 inches), the highest recorded for 150 years.

Wader interest continued from August with a Buff-breasted Sandpiper at Tinker's Marshes or 22nd. There was an obliging Eurasian Dotterei at Minsmere from 16th to 18th and up to foui Pectoral Sandpipers present in the County, part of a national influx that had begun in July There were some good numbers of other wader species also present with, for example, over 10( Common Snipe at Minsmere on 24th. Numbers of Little Egrets continue to increase and peaked in the County this month. Autumn passage of raptors included a remarkable seven Eurasian Marsh Harriers moving south off Southwold on 9th. A Eurasian Penduline Tit was at Minsmere on 29th.

October Much of the month was sunny and warm. Nearly 150 hours of sunshine were recorded in some areas and the average temperature was exceeded on a remarkable 23 days. The warmest day was on lOth, with a temperature of21C (70F). The reason was a major anticyclone, initially centred over Scandinavia, later moving to the east of Britain. This kept Atlantic fronts at bay for much of the month and measurable rain fell on only 10 days. High winds were recorded on only four days in October, notably on 24th as a deep and complex depression brought south to south-easterly winds gusting to nearly 96 kilométrés per hour (60 mph).

Predictably, passerines featured more heavily in the reports for this month. A Dusky Warbler was at Corton on 22nd and 23rd and average numbers of Pallas's Leaf W a r b l e r were reported; it was a poor year, though, for Yellow-browed Warblers, with few reported. Interestingly, a Common Whitethroat was seen at Oulton Broad on the late date of 30th, completing a long season for this species. A Cory's Shearwater off Southwold on 15th was also a late record. The highlights of the month were the discovery of a White-tailed Eagle at Covehithe on 26th and an influx of Pallid Swifts on 31 st. The eagle was one of several in the country in the autumn and it

10

Review of 1999 remai ned in the County until the New Year. The swifts remained only one day but at least two birds were involved.

November In the first week of the month the weather was dominateti by a depression tracking across the County from the south-west.

Then an intense anticyclone dominated leading to north to north-westerly winds and a cold Speli. Temperatures were parlicularly low from 17th to 23rd, when day-time readings of 6C (42F) were the equivalent of-2C (28F) when wind-chill was included. After 23rd southpesterly airstreams again dominated.

Strong northerly winds on 7th, associated with the arrivai of the anticyclone, produced a massive movement of birds off the coast. Over 500 Little Gulls (the highest ever day-total for the County), 3400 Black-legged Kittiwakes, and 17 Pomarine Skuas were recorded. In addition, 50 skua sp. passed Thorpeness that day, most of which were thought to have been Arctic Skuas.

Also on 7th, three Common Cranes passed over Benacre. Numbers of Common Wood Pigeons passing south were well down on 1998 but Landguard still recorded 7860 on 3rd. There were plenty of Black Scoters offshore during the month and into December. There were few records of Smew; the only one for the second-winter period was recorded this month. Other duck records included an unexpected inland report of two Long-tailed Ducks circling Nunnery Lakes, Thetford, on 24th, a species which has been scarce even on the coast in recent years. A very late Osprey was seen at Thorington Street, flying along the River Stour on 9th, completing a record annual total of 48 in Suffolk.

December The year ended with unsettled weather. alternating between mild and cold spells. Snow, brought by cold north-westerly winds, feil on 15th. There were several storms bringing gale-force winds; one towards the end of the month led to the loss of electricity supply for 5000 homes over Christmas and the toppling of many trees. However, there were also spells of sunshine throughput the month.

The star-turn of the month, an Ivory Gull found at Aldeburgh on 7th, was a very unexpected record. It remained until 3Ist, attracting many admirers during its stay. The Black-headed Gull â&#x20AC;˘ roost at Lackford reached 20000, approaching the high number seen on the coast earlier in the year. What with 1500 Lesser Black-backed, 700 Mew and 150 Great Black-backed Gulls you have to wonder how they all managed to squeeze in. Back at the coast, there was a movement of Little Auks on 5th. when 21 passed off Southwold and 10 Pomarine Skuas were off Covehithe on 3rd.

Gary Lowe, Boyton.

S uffolk Bird Report 1999

Caspian Gull Larus cachinnans in Suffolk - identification and status Brian Small In Britain, it is generally agreed amongst those who watch gulls, if not yet by the British Orni thologists' Union Records Committee (BOURC), that the Herring Gull Larus argentatus comple: is actually represented by a number of species: Larus argentatus/argenteus, known as Herrinj Gull; L michahellis, Yellow-legged Gull; L cachinnans, referred to as Caspian Gull; and 1 (argentatus) smithsonianus, American Herring Gull. Other species which have been claimed bu not confirmed as occurring in Britain can also be placed within the Herring Gull complex: L ar menicus - Armenian Gull; L vegae - Vega Gull, and L mongolicus - Mongolian Gull. There art two further races, heuglini and taimyrensis which are variously treated as sub-species of Herrinj Gull (Grant, 1986) or Lesser Black-backed Gull L fuscus (BWP) but which are likely to be ; separate species, known as Heuglin's Gull (sometimes as Siberian Gull).

Recent advances in identification skills, increasing experience of a wider variety of (sub-) spe cies, and more sophisticated taxonomic techniques are likely to result, firstly, in the British Bird; Rarities Committee and BOURC accepting that Caspian Gull has occurred in Britain, then in the BOURC assessing (and probably confirming) the elevation to species level of the following, al of which occur in Suffolk (but don't hold your breath).

• •

•

Herring Gull L argentatus argenteus, breeding in NW Europe (Britain, the Netherlands ano northern France), and argentatus, breeding in Fenno-Scandia and east into Russia.

Yellow-legged Gull L michahellis, breeding west from Turkey, through the Mediterranear región into the Atlantic, the Canary Islands and Azores (as atlantis), north along the western coast of Portugal and France (sometimes described as further poorly defined sub-species).

Breeding now occurs in the Netherlands and Britain (although they are currently readily hybridising with Lesser Black-backed Gull L (fuscus) graellsii). In western France it is beginning to displace Herring Gull as the dominant species.

Caspian Gull (also known as Pontic or Steppe Gull) L cachinnans, breeding north from the Black and Caspian Seas towards Moscow, and east through the 'Steppe' región (as barabensis) where it meets Mongolian Gull L mongolicus.

Speculation surrounding the impending taxonomic changes has engendered a great deal of interest in Britain. Within Suffolk, this and the ringing programme on Orfordness, in which colour rings, legible in the field, have been attached to the legs of Herring and Lesser Black-backed Gulls, have led to more detailed study of large gulls over the last two or three years. I have spent virtually all of my last two years' birding time watching gulls in the Southwold and Blythburgh area, and have made detailed observations particularly around the pig fields and estuary at the latter locality. The following discussion looks at the structure, moult, mantle tone, and behaviour of Caspian Gull, based in particular on my experiences in Suffolk, Israel and Europe and the current literature. A number of 'video-grabs', taken through a telescope, also ¡Ilústrate the article; they are not of photographic quality but show the features discussed.

There are three main recent references for the identification of cachinnans, namely Garner and Quinn (parts I and II, 1997), lonsson (1998) and Bakker (2000), and for more detail on aspeets of moult, distribution and identification these are essential. The first two articles deal in detail with adults, leaving younger birds with more superficial treatment; the last concentrates on the immature plumages, illustrating the advances made recently. Other references, e.g. Harris, Shirihai and Christie (1996) are actually ambiguous, in as much as it is sometimes difficult to tell which (sub-) species they are dealing with and even imply that immature birds are inseparable, as indeed does Grant (1986) - the illustrations by Harris et al look like michahellis and the text contradicts the

12

The Caspian Gull in Suffolk more recent (and correct) papers. f i shall concentrate on the identification of those Caspian Gulls 1 have seen in Suffolk, most of them in winter. Although structure is often the first pointer towards a Caspian Gull, plumage détails, supported by moult and behaviour, are ultimately of more importance in correct identification, I would suggest that any acceptable description needs to deal with the first two in great détail.

Status of Caspian Gull in Suffolk Its grouping with Yellow-legged Gull has obscured the occurrence of Caspian Gull in Suffolk. I am of the opinion that the BOURC's delay in dealing with the issue has engendered a general indifférence amongst birders about its identification and occurrence. An examination of past 'Yellow-legged Gull' records in Suffolk throws up strange patterns which do not necessarily follow those of other counties: Suffolk records have previously tended to fall in the late-autumn and winter periods which can be compared, for example, with Essex, where numbers peak in late summer and early autumn. These anomalies are hard to understand; certainly, my sustained efforts in 1999 have produced a sériés of records that closely follow those of Essex.

At one stage the SORC put the assessment of records into a state of limbo, in which records were pended until greater knowledge threw more light on them - John Cawston's efforts in Suffolk have slowly turned the tide. In hindsight, and with recent increases in the understanding of the complexities of the identification of the group, this was probably correct. Nevertheless, records for most years were accepted.

The récognition of cachinnans in Britain is a recent phenomenon, and may indicate that we have overlooked them, in the past. More probably the records reflect the increase in gull populations coupled with improved skills. Confirmation that Caspian Gull was being seen in Britain Carne with Martin Garner's ground-breaking article in British Birds (1997), and records in Suffolk promptly followed.

My observations at Blythburgh indicate that numbers of Yellowlegged Gulls peak in the autumn, and decrease fairly rapidly thereafter (coinciding with the departure f f Lesser Black-backed Gulls).

They appear again in small numbers with the return of Lesser Black-backeds in mid to late FebTuary. Caspian Gull may be slightly less regular in winter than Yellowlegged, but is more distinctive and l a s i e r to identify.

Caspian Gull appears to winter annually on the River Blyth and the fiearby pig fields in small numbers. , Firs,.summer caspian Gull So tar it is apparently rare in other areas of Suffolk. From the records, I suspect that some may arrive from mid-August, but then continue inland to other sites. Single-day records in late January and early February may be those exiting inland sites to Jhe North Sea. I would also suspect that, as the returning adult from 1998/1999 shows, some might recur annually. Observer awareness (or lack of it) is stili hindering its true status. It is a majestic and, once known, distinctive gull and hopefully in the near future more birders will start lo find them in other parts of the County.

The first fully described record of a Caspian Gull in Suffolk was of a third-winter at Lackford WR in December 1998. Since then there has been a sériés of records, principally from the

13

S uffolk Bird Report

Cachinnans, September 9th, 1999. Note P9 (second outer) is missing; P10 (outer) is about to be shed.

• • • •

1999

Argentatus, September 11th, 1999. Note P10

is ol&

P8 and

Pg are

growing

The post-juvenile head and body moult in autumn makes michahellis resemble Herring Gul more closely, whilst cachinnans remains relatively white-headed and -bodied; The presence of moulted wing-coverts in late first-calendar year birds excludes argentatus; First- (or second-) winter gulls on which the head and body are virtually white in Februar) March are worth looking at closely, but may not always be cachinnans'.

On second-summer Caspian and Yellow-legged Gulls in spring and early summer, there ii sometimes at least one new grey tertial and some grey wing coverts. On the second-summei at Blythburgh pig fields in July 1999 the whole of the median coverts were grey (as was th. mantle), forming a band across the rest of the very bleached wing. Herring Gull usuali) shows immature-looking tertials and wing coverts, until its moult later in the year.

Wing-tip pattern of adults The pattern of black and white of the outer primaries on adult Caspian Gulls is relatively well documented (cf. Jonsson, 1998 and Garner and Quin, 1997). The pattern of the outer primaries iquite similar to argentatus with the extent of black being restricted and white more extensive The longest, outermost primary (PIO) has, typically, black along the outer edge of the feathei crossing it as a narrow band near the large white tip, and a long pale-grey tongue runs along th inner web. Sometimes the white tip meets the tongue and sometimes it has small black notchenear the tip. See plates 4. and 5.

4. Adult Caspian Gull, Blythburgh, January 5th, 2000.

5. Near-adult Yellow-legged Gull, Southwold, November 22nd, 1999.

Behavioural characters The iong-call' display posture is described as being like that of an albatross Diomedea sp., with the head thrown back and the wings outstretched. On rubbish tips and on the pig fields cachinnans is aggressive, often adopting this posture towards other gulls - they do seem to like lifting their wings more regularly than other gulls.

16

The Caspian Gull in Suffolk

Summary of Important Features Without repeating too much of the previous sections dealing with structure, the following sumDiarises the key features to look for when identifying cachinnans of ali ages .

Juvenile Caspian Gull Crucial features are structure, but especially detailed examination of plumage.

Size, structure and behaviour This structural description stands for all ages.

The head is proportionately quite small and pear-shaped, showing the characteristic 'snouty' look of cachinnans, which is further enhanced by the long and slim bill. I liken it to that of a Slender-billed Gull La rus genei. The nape may appear to have a slight crest, or square shape.

• The ehest is high and proud, extending onto a rounded belly.

• The wings and body are long, with the fiat back lacking the more prominent tertial-step of argentatus and the primary extension stretches well beyond the tail tip. The primaries themselves look thin.

• When swimming, the wing points are held high, making it look like a large phalarope Phalaropus sp.

• When standing, the legs are very long compared with argentatus (in flight almost reaching the tail tip). From the front they appear thinner. The feet also look big.

• In flight, cachinnans takes on a much more commanding appearance: long and broad wings produce a strong flight, with the wings looking more pointed than juvenile argentatus. The neck is longer and the breast seems to 6. First-winter Caspian Gull, Blythburgh, bulge.

February 2000.

The long legs of this bird are remarkable, as is the Plumage whiteness of the head and body in comparison E There are subtle but clear distinguishing with the first-winter Herring Gull to the left and the I satures which, alongside the structural feasecond-winter Herring Gull to the righi. l a r e s , are very important.

I Head Compared directly with juvenile argentatus, the head is notable for being much paler. Virtually unmarked white from a distance, sparse and fine brownish-grey streaks are visible on the rear crown and ear coverts (tightly around the eye, highlighting narrow eye crescents). These marks strengthen onto the nape and hind neck. The lores and area around the bill are unmarked.

I Mantle a n d scapulars From a distance these are an even-faded sepia-grey (the colour of wet mud). Closer to, they appear ali neatly fringed with a thin cream-white edge, totally lacking any notching, similar to that of a juvenile Mew Gull L canus. There may be newly moulted scapulars, showing as black diamonds with broad white tips near the neck or as black bases connected to narrow sub-terminal anchor marks by a black shaft.

• Wing coverts Similarly marked to the mantle, with sepia-grey centres and neat off-white fringes, which become darker on the marginai coverts. The median and greater coverts are more broadly tipped whitish. The inner greater coverts show characteristic internai pale markings, similar to some graellsii - this marking is totally différent from the strongly notched inner greater coverts of argentatus and michahellis. When very fresh, the remaining •

17

S uffolk Bird Report

• •

•

•

•

•

1999

greater coverts are tipped broadly off-white, which extends up the outer edge, narrowiti towards the base and towards the outer wing. The overall effect of the mantle, scapulars an coverts is, from a distance, that of an even-brownish-grey.

Tertiais Contrastingly black, with neat white edges (thumbnails) at the tips, but occasioi ally also with faint internal marks near the tip.

In flight the upper wing seems generally quite pale with two darker wing bars formed by ti dark bases and pale tips of the median and greater coverts. These contrast with the blac secondary bar. The inner primaries are paler than the outer forming a pale window, muc paler than that of graellsii and michahellis.

U n d e r p a r t s Unmarked white, but on the breast sides and narrowly along the flanks thei are usually brownish blotches or crescents. Head on, these may form a broken pectoral barn but are stili distinctly whiter than argenlatus and most graellsii. The undertail coverts ar sparsely marked with neat black diamonds or crescents.

Underwings A very distinctive feature, and at the present state of knowledge thought to be diagnostic of cachinnans, is shown in flight: the underwings are almost entirely white. There may be extremely faint barring on the axillaries, some marginai coverts and tips of median and greater underwing coverts, but in most views they appear virtually unmarked. The underside of the remiges, particularly the primaries, are silvery or white, appearing translucent with only 7 the tips of the outermost primaries being • First-winter Caspian Gull, Blythburgh.

The same bird as the darker, forming a thin dark bar along the Precedin9 piate. rear edge of the outer wing.

Tail and tail coverts A distinctive feature, likened to that of Rough-legged Buzzard Buie lagopus, is that the rump and uppertail coverts are virtually unmarked white, with only sma black spots or bars noted near the tips of the longest upper- and undertail coverts respec tively. The tail is basally white, but shows a broad black tail band and white tip. On the uf per edge there is usually a small amount of narrow barring near the black, and there is, whei fresh, also a broad white edge to the outer tail feather enclosing the black.

Bare p a r t s Structurally different (as described above), and the colour of the legs is subtl different; i.e. a paler orange- or yellow-flesh, brighter than argentatus.

First-winter Caspian Gull Again, striking structural differences are one of the first clues to the identity of cachinnans, is the markedly white head and body.

a:

Plumage Identification characters (aside from structure) which identify first-winter and first-summei Caspian Gull are as follows.

• •

Bill Long and slim; ali dark, but sometimes with a lighter greenish or pinkish base; ne marked gonydeal point.

Head Usually clean white but not always unmarked. Importantly, the head is always whitei than michahellis and argentatus, but not always whiter than graellsii. A neat half collar ol dark marks forms a shawl, extending onto the mantle.

18

The Caspian Gull in Suffolk a i

k n e

9. First-winter Yellow-legged Gull, Southwold, December 1999.

8. First-winter Caspian Gull, Blythburgh, March 2000.

Note the very white head and body of cachinnans, with a small head on a large body, a long fine Pili, black tertials and contrasting dark/light greater covert bar. On michahellis, following a body moult, the head and body are more streaked, particularly around the eye. The mantle/scapulars are strongly marked with anchor shapes, and the greater covert bar contrasts less with the rest of the upper wing. Of interest, also, is the very early moult of michahellis, where the tertials, inner greater coverts and some median/lesser coverts are new - this is much too early for argentatus and more contrastingly patterned than the new, but greyer coverts of cachinnans. Not visible here are the less marked white upper- and undertail coverts of cachinnans and broad black tail band, compared with the neat black diamond spots on the uppertail coverts, chevrons on the undertail coverts, and narrower black tail band of michahellis. Other structural features would be: the shape of the head - finer and more 'snouty' on cachinnans, more angular on michahellis; the legs - longer and thinner on cachinnans, stronger and marginally shorter on michahellis (I would say that both are longer-legged than argentatus, and both have pater, flesh legs).

•

U n d e r p a r t s Virtually unmarked white, although some faint dark Spotting or barring maybe visible on the upper flanks.

> • I

Mantle and scapulars Largely plain grey with some black spots and bleached areas. Some scapulars show a pattern of a large black basai diamond joined to a very narrow dark crescent near the tip.

Wing coverts The best character would be the greater coverts whose dark base and pale tips form dark and light bands across the wing, contrasting with increasingly worn, even pale biscuit-coloured, median and lesser coverts. From January onwards there may be a few new black-centred coverts (ruling out argenteus). A contrasting dark carpai mark is noted on the closed wings and especially when the wings are opened.

Tertials Black, becoming faded . Pattern of pale tips are stili visible.

Tail and tail coverts Prominent black tail band highlighted by white base and white, unmarked upper- and undertail coverts, although the latter are sometimes marked with obscure small crescents.

Underwing Very white with, on some, faint brown barring on axillaries and on marginai underwing coverts. The whiteness extends right across the remiges, with a dark trailing edge to the wing tip.

• ]

• • • •

Second-winter and -summer Caspian Gull .

An observer should be immediately struck by the structure; the head and bill shape should be really quite remarkable. Very long-winged and, in flight, very broad-winged, with a long neck and feet that reach virtually to the tip of the tail.

19 J

Suffolk Bird Report

1999

Plumage • • •

• • • •

Head a n d u n d e r p a r t s These are white. In early winter there is a half-collar of dark spots o the rear neck, but this is unmarked by summer M a n t l e A mid-grey, darker than Herring Gull and equal to a third-summer michahellis, wit a mixture of dark marks in early winter, but totally grey by spring or early summer.

U p p e r - w i n g coverts Again a mix of new grey (usually median and some greater) and darl centred coverts. By summer the coverts are very faded, almost white, with new coverts form ing a grey band across the inner wing.

Tertiais Faded black with whitish tips, some moult to adult-like grey.

U n d e r w i n g White. Distinctively, the underside of the primaries are also very white wit much less black than on michahellis and argentatus. Some show a white mirror on PIO. Tail White, often marked by a broken tail band.

B a r e p a r t s The bill is remarkably long and quite streng and noted as pale creamy-yellov (sometimes pinkish-yellow in early winter) with a broad black band near the tip. The legs ar long, slim and pale yellow-flesh - more orange coloured than on Herring Gull. Eye, dark.

Third-winter Caspian Gull By its third winter, Caspian Gull has fourth-generation feathers, and looks intrinsically like ai adult. Close observation will usually reveal immature feathering on the marginai, lesser and inne greater coverts. The bare parts are also duller than on adults with more black on the bill.

Plumage •

•

• •

•

•

H e a d This seems smaller, finer and whiter than on surrounding Herring Gulls, lacking th latter's bulky feel and usuai fairly prominent streaking. In winter, it has a half-collar of spars dark streaks on the hind neck, but the underparts are wholly white.

Mantle, scapulars and wing coverts Generally grey like the adult, but signs of immaturit; can sometimes be seen on the marginai coverts, forming a dark leading edge to the wing. In ner greater coverts are slightly paler with faint brownish marks.

Tail This has a vestigial tail band of isolated black marks.

Underwing The underside of the wing is white apart from restricted black near the tips of the outer primaries. This is very distinct from argentatus and michahellis, as is the prominent white mirror on PIO, which is indistinct or absent on Herring or Yellow-legged Gulls of the same age.

Tertiais These may be largely adultlike but some may have black ovai spots at the base.

Bare parts The bill is slim. pale milky-yellow, becoming richer in 10. Third-winter Caspian Gull, Blythburgh, January colour in the late winter. It has a neat 2000. Note small white head with minimal streakdark band near the tip, sometimes ing on the nape and thin greyish legs. In flight this bird was very white on the underwing, and the with a red 'shadow' on the distai part black marks on the tail, just visible here, formed a of the lower mandible. Legs are neat but broken tail band. longer than argenteus and subtly finer, but notably pale grey becoming pale flesh-pink on the feet (argenteus may occasionali) be grey-pink). The eye seems very small and dark compared with the pale iris and surround ing smudgy area of Herring Gull.

20

The Caspian Gull in Suffolk

Adult winter Caspian Gull In late winter this age becomes perhaps the most difficult to identify. Up until this time the majority of Herring Gulls have streaking on the head (usually quite heavy), whilst Caspian Gull and Yellow-legged Gull are unmarked (or virtually so). Key features are structure and plumage détails, in particular head and bill shape, tone of mantle and a detailed note of PIO pattern.

Usually a very large gull, with a long primary projection. The head is small with the crown typiŒlly rounded, a slight crest noted on some occasions when at rest - when the head is lifted up it is very like a Mew Gull. The bill and legs are long, the bill being particularly noteworthy.

Plumage •

•

•

•

•

Head Virtually unmarked white at ali ages.

By early September a few brownish streaks may be just visible on the hind neck and above the eye. The remainder of the underparts are white.

Mantle The mantle tone is frequently very close to that of Mew Gull. In direct comparison with argenteus Herring Gull it is darker and alongside michahellis it is paler or equal in tone.

Tertiais These have narrow white tips and are held fiat against the body giving a flat11. Adult Caspian Gull, Blythburgh pigfields, January 2000. backed appearance.

Primary moult A little later than michahellis in my experience, matching that of Herring Gull. In early August an adult has the outer two primaries faded black with PIO having a whitish inner tongue, a white mirror and narrow sub-terminal band. By September, PIO is still retained, P9 is just beginning to grow; P8 is virtually fully grown. The typical pattern of PIO for Caspian Gull is described previously.

Bare parts Bill colouration changes from a green-yellow in July to a more grey-green colour

by September and pale or even richer yellow by mid winter. The eye often appears dark in comparison with argentatus, but may appear pale in close views. The legs are long, thin and coloured flesh; only very rarely are they yellow.

Brian

Small,

Southwold.

References Bakker, T., Offereins, R„ and Winter, R„ 2000. Caspian Gull Identification. Birding World 13:2, pp.60-74. (ferner, M and Quinn, D, 1997. Identification of Yellow-legged Gulls in Britain, British Birds 90: 25-62 (Pt. I),

British Birds 90:369-383 (Pt. II).

Qrant, P, 1986. Gulls, a guide to identification, Poyser, Calton ® r r i s , A, Shirihai, H, and Christie, D, 1996. Macmillan

Birders

Guide to European

and Middle

Eastern

Birds, Macmillan, London.

Jonsson, L, 1998. Yellow-legged Gulls and yellow-legged Herring Gulls in the Baltic, Alula 3/1998: 74-100 Shirihai, H, 1996. The Birds of Israel, Academic Press, London Websites Martin Reid

www.martinreid.com - armenicus, michahellis, cachinnans

Bob Lewis

www.bway.net/~lewis/birds/gulls.html - argentatus, michahellis

S e v e Hampton

www.west.net/~dj/gulls.htm - michahellis,

cachinnans,

Rudy Offereins www.geocities.com/RainForest/Jungle/7550

21

barabensis,

armenicus

S uffolk Bird Report

1999

THE BREEDING BIRD SURVEY Introduction This is, essentially, the second part of the paper that appeared in the Suffolk Bird Report (SB Vol. 48. Please refer to Vols. 45 and 47 for more détail on the BBS in Suffolk. To produce mea ingful data from the survey relating to Suffolk, at least 100 tetrads should be covered. Unforl nately, we are far below that number. The simplicity of the methodology (two visits along d fined routes) means that most birdwatchers can participate. A glance at the contributors' list eli where in this Report shows that there are many more than 100 active birdwatchers in the Coum A list of the participants in the BBS is appended to this paper. If your name is in the list of co tributors but not in the BBS list, then it should be!

As before, caution should be exercised in reading too much into an analysis of the data. T sample size is stili too small and the period of the survey, too short to be able to confidently a sess trends.

Coverage Despite appeals in previous Reports, it is sad to report that the number of squares covered 1999 showed a decline from the previous year. Only 39 tetrads were covered compared with • in 1998 and 42 in 1997.

Results By far the highest number of species was recorded in 1999, at 113 (103 in 1998). The previo¡ highest was 105 in 1996. The lowest was the 91 species recorded in 1996.

Strangely, coupled with the high number of species recorded, there appears to have been i increase in the numbers of many of the birds recorded. The reasons for this are unclear.

The format for more detailed examination of the results from the Suffolk squares follows t from last year. That is, the remaining five species included on the red list of Birds of Conserv tion Concern are discussed, along with other species arbitrarily chosen as being of interest.

Without access to a detailed statistical analysis of the data the following is based, by necessit on simple principies. Ideally, only the squares that were surveyed in three or more years shou be included in the analysis. This would prevent an unusual resuit in one square biasing the resuit Unfortunately, that has not been possible and the analysis is based upon the whole of the resul for each year. As more squares become surveyed the effect of any bias will become less marked Each species is examined in terms of two simple measures. Firstly, its distribution, shown ; the percentage of the total squares surveyed in which it was recorded. Secondly, its a b u n d a n c shown as the mean of counts across ali the squares in which it was recorded. These are shown t means of a table; the data are that from the Suffolk squares only. The limitations of the sma sample size must always be borne in mind when interpreting the data.

• G r e y l a g / C a n a d a Goose The national BBS survey results for the period 1994-98 indicated a 25% increase in the nun bers of Canada Geese and a 31% increase in the Greylag Goose population. The results for 199 showed a large increase in Greylag numbers (47% more than in 1998) and a decline in Canac

22

The Breeding Bird Survey Gòose numbers (6% less than in 1998). Nationally, figures for the period 1994 to 1999 show a 100% increase for Greylag Geese and an 18% increase for Canada Geese. This divergence was n©t reflected in the results from Suffolk; the relative proportions of the two populations have remained broadly stable.

• Eurasian Sparrowhawk The Eurasian Sparrowhawk has certainly seen a considerable change in fortune over the past 40 ytars. From the nadir of the mid-1960s, numbers have recovered extraordinarily well. The past 20 years of national CBC survey results show a 294% increase. The Garden Bird Survey, organised by the BTO, shows nearly a 50% increase in gardens over the same period. The national results of the BBS survey, which only cover the period 1994-99, show a more stable picture.

There was actually a decline of 2% in the 98 99 94 95 year 1998-99 but over the whole period — mean count -%age of squares Mere has been an increase of 1%. In Suffolk, both distribution and abundance show wliat seems to have been a decline in the mid-period with a late recovery. Overall, the results indicate a stable population over the period, in line with national results.

• Northern Lapwing (Amber List) jt seems stränge to think now that the Northern Lapwing was once such a common breeding bird that its eggs were collected for the table. National figures show a 49Ve decline over 11 years, with the BBS slowing an 18% decline over the five-year ptriod to 1998. There was a further decline in 1999, giving an overall 20% decline for the period 1994-99. Strangely, the results for Suffolk do not appear to give such a - m e a n count - a — % a g e of squares clcar-cut picture. Although numbers have continued to decline, distribution went up in 1999.

•

European Turtle Dove (Red List) This is a species that has been used as another high-profile example of the plight of formerly common species. National survey rlsults have indicated that a retreat from the north and west of its range. Recent research has indicated this may partly be due to a shorter breeding season caused by intensive farming (British Wildlife 11:3, 208). National BBS results show a steep decline of 9% between 1998 and 1999 with an overall decline of 18% for the period 1994-99. The Suffolk results clearly indicate a decline, which appears to be worryingly steady.

94

95

96

97

98

99

-%age of squares — .— mean count

23

Suffolk Bird Report 1999 •

Common Wood Pigeon There have been some very high counts of this species in recent years, particularly in the autumn (see Suffolk Birds 48:95). BBS survey results in Suffolk seem to indicate an increase in numbers.

This is also supported by other surveys. The Garden Bird Survey indicates a 53.4% increase in garden records over the period from 1970 to 1990.

This figure is remarkably similar to the 55% in%age of squares - mean count crease indicated by the CBC results over the same period. However, the national BBS figures show no change between 1994 and 1999 and onl; marginal increase over the last year of the survey.

• Song T h r u s h (Red List) Song Thrush is another of the species used to highlight the decline of familiar garden birds. In fact, its position seems to be improving according to the national results. Over the period 1994-98 there had been a decline of 1% in its population according to the national BBS results but an increase of 6% over the year 1998-99 has meant an overall recovery of 6% for the period 1994-99.

94 95 96 97 98 99 Results in Suffolk appear to agree, showing a re-%age of squares —< — mean count covery over the past few years. This may be attributable to greater success in gardens (see Systematic List, later in Report).

• Eurasian Tree Sparrow (Red List) National CBC results show that Tree Sparrow numbers have dropped by an incredible 87% over the past 20 years. Data from the Garden Bird Survey indicate a less dramatic decline; relatively they have become seven times more numerous in gardens. This clearly shows the value of gardens both as refuges and feeding areas. According to 94 95 96 97 98 99 the national BBS results, 1999 was a good year — %age of squares —< - mean count for this species. An increase of 21% over the 1998 figure meant a turn around from a decline of 8% over the period 1994-98 to an increase of 119! over the period 1994-99. In Suffolk, the da are not clear, possibly as a result of the small sample.

• Common Bullfinch (Red List) National CBC results show a 62% decline in numbers over the past 20 years. As with mai other species, the decline has been less steep in gardens, as shown by the Garden Bird Survey, 5 35 S 30 • where there has been a 14.5% decline over the 4 . " " A c § 25 same period. National BBS results add no com3 É §" 20fort, showing a 28% decline in the population o 15 V / between 1994 and 1999. However, the decline * — • — ^ & 10- . between 1998 and 1999 was less severe, at 1%. In * 5Suffolk, this slight improvement appears more 0 — i — i — — i — i — marked. Hopefully this signals further improve94 95 96 97 98 99 ments in the future. %age of squares mean count

\

24

i -

/

The Breeding Bird Survey •

Yellowhammer National survey results show this to be a declining species; a 60% decline in population according to CBC results over the past 20 years, and a 16% decline in the period 1994 to 1999 according to national BBS results. The déclinés are such that it is suggested in some quarters that Yellowhammer should leap from the Green List straight to the Red List of mean count %age of squares Birds of Conservation Concern on the next revision. Against this the national BBS results showed a stable population over the year 1998-99 and the Suffolk results appear to agree.

•

Corn Bunting (Red List) Another species which, although clearly in severe decline, showed some signs of recovery in 1999. From 1994 to 1998 the national BBS results had shown a decline of 42% in the population. A recovery of 28% over the year 1998-99 has cut that to a 26% decline.

Again, the Suffolk results appear to tally, showing a recovery in 1999.

-- 1

%age of squares -

- mean count

Summary The Common Bird Census used to be the only practicalable method of monitoring the population of common bird species. Since the introduction of the Breeding Bird Survey the corrélation of the results from the two surveys have been checked. The BTO is now confident that the BBS can not only deliver meaningful results but is a much simpler method and, as a conséquence, the CBC has recently been dropped. Hopefully this paper demonstrates that, not only will participation contribute to the national results, it also gives an insight into bird populations here in Suffolk.

If you want to become involved contact either Mick Wright (tel.01473 710032; e-mail: nd|ckwright@talk21 .com) or Richard Bashford at the BTO (tel.01842 750075). <Miry Lowe, Ayton.

Fieldworkers 1999 G Albon, K Aveling, A Banister, G Bigg, D Blamire, M Buckingham, S Carmichael, S Clarke, P Cloke, J & A Garstang, J Glazebrook, A Gooding, T Gray, A Gretton, S Jarvis, B Lockhart, G Lewe, J MacGuire, S Marginson, T Oliver, G Oram, W Patrick, G Siriwardena, T Sivyer, D Spender, B Thompson, D & J Toomer, J Turner, J Walshe, A Wilson, G Woodward, P Vincent.

REFERENCES: • e a d . , C . 1999. Wildlife Reports, British Wildlife 11(1), 52-54 & f i (3), 206-208.

Noble, D.G., Bashford, R.l. et al. (1999) The Breeding Bird Survey 1998. BTO.

25

Suff Olk Bird Report

1999

THE 1999 COMMON NIGHTINGALE SURVEY IN SUFFOLK Andy Wilson and Mick Wright The Common Nightingale Luscinia megarhynchos was known to be in decline in Britain 1 much of the second half of the 20th Century, being virtually lost as a regul채r breeding species parts of the English Midlands (Gibbons et al 1993, F체ller et al 1999). In 1999 the British Tri for Ornithology (BTO) co-ordinated a national survey of the Common Nightingale, the first sir.

1980.

The History of the Common Nightingale in Suffolk The status of the Common Nightingale in Suffolk reflects the variations in numbers across Bi ain over the last 100 years or so. Described as "common everywhere" in 1884 (Babington 188 86) and "common in suitable places" in 1932 (Ticehurst 1932), there were signs of increasi numbers during the 1930s followed by a decrease since the 1950s (Payn 1978). D체ring the 19 Common Nightingale Survey, 367 singing males were found in Suffolk, 7.7% of the national i tal of 4,770 males (Davis 1982). The majority of these birds were found in the coastal belt a the south of the County with only 34 singing males in the Breck and Fens and very few in mi Suffolk (Brown 1981).

The Suffolk Bird Reports do not indicate that there has been a major change in the status of tl species in the County since the 1980 survey. The number of singing males reported fluctuat between 122 and 218 per year between 1981 and 1992 with no discernible trend, although t 1997 report did suggest that Common Nightingales were becoming more localised in distributi in the County. Numbers appear to have fallen slightly at Minsmere where counts have fluctuat between 20 and 38 singing males during the 1990s compared with a record total of 62 males 1989. Numbers have also dwindled at Bradfield Woods (R F체ller pers comm.) and Wolv Wood but, in contrast, there was a steady increase at North Warren from 11 males in 1991 to in 1997. However, it is impossible to draw conclusions about the status of the Common Nighti gale across Suffolk from these counts, as they give no indication of numbers away from the: important nature reserve sites.

Results of the 1999 Survey During the 1999 Common Nightingale Survey, all sites where Common Nightingales were i corded during the years 1988 to 1997 were visited, along with those where Common Nightingali were located in 1980 survey. No less than 881 singing males Common Nightingales were four in Suffolk in 1999, a total 140% higher than that for the 1980 survey. As in 1980, the main coi centrations were in the east and south of the County, with other concentrations in the Fens an Breck in the northwest but rather few in southwest, central and north Suffolk. The largest propo tionate increases were in the Brecks/Fens (an increase of 267%) and the north and northeast (u from 6 in 1980 to 39 i 1999).

Area 1980 total 1999 total % change Records were receive 1980 to 1999 % from no less than 22 Coastal Belt 144 297 +106 tetrads in 1999 (see maf Breckland and Fens 34 +267 125 and 78 parishes - aroun South and southeast 162 364 +124 one quarter of all parishe Central 21 56 +166 in the county. The bei North and northeast 6 39 +550 parishes for the Commo Population changes between 1980 and 1999 in areas of Suffolk Nightingale in 1999 wer (see Brown 1980).

26

The Common Nightingale

Survey

Distribution of singing male Common Nightingales by tetrad, 1999

I

r

1

Westleton (64 singing males). Dunwich (40), Bentley (30), Hadleigh (28), Walberswick (28), Blvthburgh (24), Layham (24) and Sutton (24). Further inland, the parishes along the Breckland/ Fen edge also held good numbers with 15 at Red Lodge, 14 at Eriswell, 11 at Mildenhall and nine at Lakenheath. The best sites included Dunwich Forest where 44 singing males were located (compared with only one in 1980), Minsmere (29 males - about average for recent years), Aldringham Common/The Walks (18), Red Lodge Common/Warren (17), North Warren (14), Cit-off Channel (14), Foxhall Heath (12) and Market Weston Fen (12).

• Habitat Use Scrub is by far the most important habitat for the Common Nightingale in Suffolk, probably d S T 6 S ° t h a " e l s e w h e r e i n t h e s o u t h o f England (Füller et al 1999). Almost half (46%) of all Common Nightingale territories located in Suffolk in 1999 were in scrub with a further 9% in f ^ x ' ^ e r o w s - m a n y of which are overgrown or abandoned hedges. Many of the Common Nightinr g J e s now found in Dunwich Forest are in scrub regenerating in areas flattened in the great storm oft 1987. Common Nightingales also appear to have colonised recently developed scrub in other L » a s > such as on the banks of the Cut-off Channel along the eastern edge of the Fens. Coppiced Jwoodland is relatively scarce in Suffolk and only 28 birds were found in such habitat in Suffolk in 1999. A further 227 were found in mixed and deciduous woodland and 83 in carr or willow scrub.

Diseussion JThe 1999 survey has revealed that Suffolk supports a much larger population of Common Nightingales than was previously thought. Allowing for overlooked birds, the late Brian Brown

27

Su ff Olk Bird Report

1999

estimateci than the population was well over 400 singing males in 1980 (Brown 1981). Natio ally, it was estimateci that 36% of Common Nightingales were missed in the 1999 survey (Wilsi et al in prep.); it is therefore likely that more than 1000 singing males were present in Suffolk 1999. While some of the apparent increase in numbers can be accounted for by colonisation new habitats, there is little evidence in Suffolk Birds of any significant change in status in t County over the last two decades. This suggests that the much larger numbers recorded in 19' were due, in part, to more comprehensive coverage. In both Essex and Kent, more Commi Nightingales were located in 1999 than in the earlier survey although these increases were not ( the same scale as that reported for Suffolk. It is clear from the national results that the Commi Nightingale's range is continuing to contract in England but that there is little evidence of a i duction in numbers in eastern seaboard counties from Norfolk south to Sussex.

At the present time, the Common Nightingale appears to be thriving in many parts of Suffol although its distribution is still constrained by the availability of suitable dense thickets, be th in scrub, carr or woodland. It will be very interesting to see what the next few years hold for ti species. The most pessimistic scenario is that the range contraction from the west will contini so that eventually Common Nightingales will be lost even from some strongholds in the ea including Suffolk. At the other extreme, it is possible that the apparent increase in numbers Suffolk in recent years spells the start of a change in the fortunes of this long-declining bird England. The Common Nightingale is a climatically-sensitive species and climate change w undoubtedly have an effect one way or the other here at the northern edge of its European range

Acknowledgements Many thanks to the Common Nightingale Survey participants, who are too numerous to list full, plus ali those who submitted casual records of Common Nightingales in 1999. The Con mon Nightingale Appeal was funded by generous support for the B T O ' s Common Nighting; Appeal.

Référencés Babington, Rev Dr C. ( 1884-1886) Catalogue ofthe Birds of Suffolk.

Brown, B J . (1981) The Nightingale in Suffolk - 1980. Suffolk Birds 1980, 35-36.

Davis, P.G. ( 1982) Nightingales in Britain in 1980. Bird Study 29:73-79.

Füller, R.J., Henderson, A.C.B, and Wilson, A.M. (1999) The Nightingale in England Problems and prospects. British Wildlife 9:221-230.

Gibbons, D.W., Reid, J.B. & Chapman, R.A. (1993) The New Atlas of Breeding Birds in Britai and Ireland: 1988-91. T. & A.D. Poyser, London.

Payn, W.H. (1978) The Birds of Suffolk, Ancient House Publishing, Ipswich.

Ticehurst, C.B. (1932) A History ofthe Birds of Suffolk.

Andy Wilson and Mick Wright, British Trust for Ornithology.

E-mail: andv.wilson@bto.org mickwright@talk21 .com