The BTO Magazine for Ringers and Nest Recorders

LIFECYCLE SPRING 2018 ISSUE 7 BREEDING SEASON RESULTS CORN BUNTINGS MONITORING SWALLOWS

TREE SPARROWS Monitoring for RAS EDITORIAL | Editorial and Contents

Editorial ISSUE 7 SPRING 2018 LIFECYCLE THE BTO MAGAZINE FOR RINGERS AND NEST RECORDERS The BTO Magazine for Ringers and Nest Recorders Welcome to the latest edition of LifeCycle. Spring finally LIFECYCLE SPRING 2018 ISSUE 7 The Ringing and Nest Record schemes BREEDING SEASON RESULTS CORN BUNTINGS MONITORING SWALLOWS arrived here in Norfolk, after what felt like a very long TREE SPARROWS are funded by a partnership of the Monitoring for RAS winter, but the cold weather of a couple of months ago BTO and the JNCC on behalf of the seemed to delay the start of the breeding season. Many statutory nature conservation bodies birds appeared to be late laying this year, which contrasts (Natural England, Natural Resources sharply with the early season in 2017. As usual, this Wales, Scottish Natural Heritage and the Department of Agriculture, Environment issue contains the breeding season results from last year, and Rural Affairs, Northern Ireland). produced from the NRS, CES and RAS data that you Ringing is also funded by The National work so hard to collect each year – our sincere thanks to Parks and Wildlife Service (Ireland) everyone for their contributions to the schemes. Thanks are also due to all of and the ringers themselves. The BTO you who have taken the plunge and embraced DemOn so enthusiastically; supports ringing and nest recording for scientific purposes and is licensed by the to date over 1,400 ringers and nest recorders have logged onto the system. statutory nature conservation bodies to The article on page 30 sets out the NRS functionality now available. We permit bird ringing and some aspects of have two articles this month that highlight the results you can achieve from nest recording. All activities described are systematic recording projects (page 11 and page 18) and another showing undertaken with appropriate licences and how a population recovery project can turn into a successful RAS. If you’ve following codes of conduct designed to ensure the welfare of birds and their nests ever considered being an NRS mentor, the article on page 15 should inspire is not adversely affected. you. And for anyone who has ever run a mile from the hornet in your nest box, the article on page 26 explains just how useful records of other taxa are CONTACT US The British Trust for Ornithology is a charity and how to submit them. dedicated to researching birds. For membership As always, we value your feedback on the magazine and content. If you details please contact: [email protected] would like to share your experiences and expertise by writing or contributing British Trust for Ornithology, The Nunnery, to a future article, we would also love to hear from you. Thetford, Norfolk IP24 2PU Tel: (01842) 750050 Website: www.bto.org Ruth Walker & Carl Barimore Email: [email protected], [email protected], [email protected], [email protected] Registered Charity no 216652 (England & Wales), IN THIS ISSUE . . . no SC039193 (Scotland) LIFECYCLE PRODUCTION News from ringing & nest recording...... 3 LifeCycle is the biannual magazine of the BTO 2017: the earlier the better?...... 4 Ringing and Nest Record schemes. It is freely available on the BTO website. First come, best served?...... 11 Articles in LifeCycle are written by ringers and nest Swallow survival: plugging a gap...... 12 recorders, so please send ideas and contributions to the editors: Novice to mentor: a nester’s journey...... 15 Carl Barimore, NRS Organiser Living on the edge...... 18 Email: [email protected] Ruth Walker, Ringing Surveys Organiser Sowing seeds of a Tree Sparrow RAS...... 20 Email: [email protected] Editors: What RIN do for the other 363 days...... 23 Carl Barimore, Ruth Walker, Richard Broughton and The Special Methods Technical Panel...... 25 Dave Leech. Layout, design, imagesetting and typesetting: What’s in the box?...... 26 Ruth Walker and Mike Toms. A better understanding of risk...... 29 Printing: Swallowtail Print, Norwich. DemOnic nesting.­...... 30 Copy dates: Are terraces a House Sparrows des res?...... 32 Spring edition – 31 December Autumn edition – 30 June ‘Aberrant’ moult: emerging trend?...... 34 Thanks to the proof readers for all their efforts. Cover CES Ringing – the European way...... 36 image: John Harding/BTO Publications...... 38 The views expressed by the Noticeboard...... 39 contributors to this magazine are not necessarily those of the Editors, the Monitoring priorities: Little Owl...... 40 Council of the BTO or its committees. Quotations should carry a full acknowledgement. © BTO 2018

2 – LIFECYCLE Spring 2018 Ringing & Nest Recording | NEWS NEWS FROM RINGING & NEST RECORDING

barn owl how to make it specialist Nestboxes

EASY-TO-USE RSPB RESERVES GUIDANCE CONSTRUCTIONWITH FlUsH RooF DIAGR AMS baRN oWl box the roof of an indoor

NESTBOXES: YOUR COMPLETE GUIDE box does not need Nestboxes DestiNeD to be placeD BUILDING YOUR OWN NESTBOX AND WATCHING to overhang the A recent review of RSPB policy iNsiDe olD FaRM bUilDiNgs caN A PAIR OF BIRDS RAISE A SUCCESSFUL BROOD entrance hole. be less WateRpRooF aND stURDY concerningWILL BRING PLEASURE ringing TO THE WHOLE on FAMILY… reserves stressed tHaN oUtDooR boxes AND THIS BOOK PROVIDES ALL YOU NEED TO KNOW TO GET STARTED. WITH NESTBOXES the value of CES and RAS,A FORWARD but not of eNtRaNce positioN BY WILDLIFE TV place the 150mmm square entrance hole PRESENTER YOUR COMPLETE GUIDE high to stop chicks leaving prematurely. STEP-BY-STEP ILLUSTRATED INSTRUCTIONS FOR pullus ringing, leading to NICKpermissions BAKER CONSTRUCTING PROVEN NESTBOX DESIGNS BY DAVID CROMACK WITH A FOREWORD BY NICK BAKER

PROFILES OF GARDEN BIRD SPECIES THAT cUttiNg teMplate being rescinded for some nest box 12mm exterior grade plywood REGULARLY USE NESTBOXES sheet size: 945mm x 2120mm projects.BOX DESIGNS This FOR LESS COMMON oversight GARDEN VISITORS has now been

PRACTICAL ADVICE ON THE BEST POSITIONS BY DAVID CROMACK corrected;FOR YOUR NESTBOXES if you wish to ring pulli on 460 HOW TO PROTECT NESTING BIRDS FROM CATS FRoNt laNDiNg iNspectioN paNel platFoRM choose the location an RSPBAND OTHER PREDATORSreserve, please follow the glue wooden battens for an inspection panel to the edge to make the based on where the box guidelinesTHE BEST MATERIALS set AND out TOOLS TOin USE the ‘Ringing on platform more stable. will be placed indoors. TIPS ON REPAIRING AND PRESERVING NESTBOXES back 460 RSPBADVICE Reserves’ ON PROVIDING REFUGES article FOR HEDGEHOGS in Issue 3 (spring 600 RooF AND OTHER GARDEN ANIMALS 2016) of LifeCycle. siDe 600

The British Trust for Jacobi Jayne & Company Published by Ornithology (BTO) is an is Europe’s leading birdcare the British Trust for Ornithology independent charity that gathers specialist. Their professional- with the support of evidence of change in bird and grade nestboxes for wild birds BTO RESEARCH GRANTS Jacobi Jayne & Company. other wildlife populations. Used and mammals are found in 900 base widely by Government and other gardens, parks, woodlands organisations, the BTO’s long-term monitoring and public spaces. They are 250x400 600 platFoRM peRcH HiNge optioNs BTOdata sets theringers standard for understanding are the eligiblealso widely specifi ed by architects, to house- apply for a Young barn owls will Hinges on the side of effects of environmental change on Britain’s birds. builders and civil engineers. Find out more at appreciate a place where an inspection panel. Combining the work of professional research www.livingwithbirds.com. Jacobi Jayne is they can stretch out. BTOscientists, Researchecologists and 40,000 volunteer Grantalso the founding sponsorof of upNational Nest to Box £500. birdwatchers around the UK gives the BTO a Week. Organised by the BTO since 1997, this 485 460 Fix nails or screws into wooden battens previously glued into position. unique, impartial and knowledgeable voice in annual event raises awareness of the need to Grantsnature conservation. are Learn more awarded at www.bto.org. create more to nesting spacesprojects for British birds. focusing PRACTICAL EXPERT ADVICE AND IN-DEPTH SPECIES-BY-SPECIES PROFILES | | on all aspects of field ornithology, 118 nestboxes your complete guide nestboxes your complete guide NB_Covers_164001/002164.indd 1 09/02/2018 9:58 particularly those most relevant to NB_Specialist_108-129.indd 118 05/02/2018 16:38 the BTO’s core research activities. such as EURING numbers to enable us contact Nicholas Watts on: Preference is given to research carried to link to other schemes as required. For [email protected] out in Britain, Ireland and other those particularly interested, we will be parts of the Afro-Palaearctic flyway updating initially to IOC version 7.3, CEH POLLINATOR SURVEY and priority will be given to well- and implementing subsequent updates While we appreciate that many ringers designed research projects that are on an annual basis. and nest recorders are already fully likely to produce publishable results. occupied during the breeding season, Projects undertaken by amateurs will NEST BOXES HIT THE MAINSTREAM some volunteers have approached us to be prioritised; however, collaboration Thanks to the very generous support of ask about other opportunities to collect with professionals, including BTO Jacobi Jayne & Company, BTO has just data on patches they visit regularly. staff, is encouraged. The closing date published a new guide to nest boxes, BTO is increasingly working with for applications is 15 December 2018. their construction and placement. CEH to collect data on other taxa; the Find out more at: www.bto.org/about- Authored by Dave Cromack and UK Pollinator Monitoring Scheme bto/bto-research-grants drawing on the expertise captured in (PoMS) seeks the help of volunteers the many previous editions of the BTO to collect data on pollinating insects, a IOC TAXONOMIC CHANGES Nestbox Guide, this new publication group whose conservation status is of The British Ornithologists’ Union will be accessible to a broad audience increasing concern. has adopted the global taxonomy and should see many more nest boxes There are two ways to get involved. of the International Ornithological erected for a range of bird species. The first involves a 10-minute Flower- Committee (IOC) and BTO is The book, which is a softback of 162 Insect Timed Count – anyone can take following suit, recognising the value in pages, is priced at £8.95. Copies can part, at any location where there are pushing towards a global consensus. be ordered from our website www.bto. flowers and insects, and a full survey We plan to align all of our surveys with org/shop or by post or phone. Please guide is provided. A smaller group of IOC, including the Ringing and Nest include £3.95 for post and packing. volunteers is required to help with the Recording schemes. We will be making systematic surveying of random sites the changes in the background in the PULLUS RINGER NEEDED across England, Scotland and Wales. next few months. Most people should A ringer with a pullus endorsement This involves ‘adopting’ a 1-km survey notice very little change, as the main is needed to help with a Tree Sparrow square, meeting on site with a PoMS differences in a British context apply to project near Spalding in South team member and visiting the square a number of vagrants (unless you ring Lincolnshire, monitoring nests and on three further occasions during many Bean Geese!). Note that whilst we ringing pulli. There are currently 170 summer to collect insects with water- will be following the IOC taxonomy, nest boxes, but that will double for filled pan traps. we still intend to take a pragmatic 2019. The ringer will also be welcome If you would like to volunteer please approach to English names. We will, to mist net on site during summer and email [email protected] and visit the of course, be maintaining information winter. For more information, please website for more details.

Spring 2018 LIFECYCLE – 3 ANNUAL RESULTS | 2017 breeding season results

2017: the earlier the better?

As mild weather brought an early start to spring 2017, ringers and nest recorders were hoping that, following two poor breeding seasons in 2015 and 2016, things

didn’t really come in threes. Cutting/BTO by Liz Warbler, Garden Thankfully, 2017 proved to be a much better year for migrants and residents alike, as Ruth Walker, Carl Barimore and Dave Leech explain.

Fewer Garden Warblers were recorded in 2017 than in any previous year since CES monitoring began.

The number of nest records submitted MIGRANT PASSERINES for all of the above-mentioned species, for the 2017 season so far is 44,498, Migrant abundance and survival with the exception of Garden Warbler, with the final number expected to reach As always, there were winners and suggesting that overwinter survival c. 45,000, a slight drop on the totals for losers during the 2017 breeding of adult birds was not the driver of 2016 (46,739), again reflecting reduced season. Three migrant species recorded the increases for Chiffchaff or Reed investment in NRS while we continue through CES declined significantly in Warbler, but may have contributed to focus on DemOn development. The 2017 compared to the five-year mean to the declines in Blackcap and number of CES submissions increased (2012–16) (Table 1). Two, Garden Whitethroat; it is possible that those to 135 in 2017, while the number Warbler and Whitethroat, are long- juvenile Chiffchaffs and Reed Warblers of RAS projects that ran was at least distance migrants, whilst Blackcap which did fledge exhibited high 196. The time and effort put into nest is a short-distance migrant; Garden overwinter survival, helping to swell recording and undertaking CES and Warbler numbers were at their lowest numbers in 2017. RAS every year is phenomenal and since CES monitoring began in 1983 While the long-term trends our sincere thanks go to everyone who and it is interesting to note that all three (1983–2017, Table 1) for all of collected data during 2017. species exhibited significant declines the long-distance migrant warblers In contrast to the previous year, in productivity on CES sites during monitored through CES show a decline winter 2016/17 was relatively dry the 2016 season. That said, numbers in abundance, the trends for Blackcap and mild until late February, when of both Reed Warbler (long-distance and Chiffchaff are both positive. conditions turned stormy. After a dry migrant) and Chiffchaff (short-distance Chiffchaffs have been recorded in and mild start to spring for most of migrant) increased significantly particularly high numbers in recent Britain & Ireland, there were numerous compared to the five-year mean, despite years; the record for the highest number late frosts in the second half of April. a similarly poor breeding performance of adults encountered on CES has May was generally warm and wetter for both in 2016; Chiffchaff was been broken in six of the past seven than average in the south-east but dry recorded in higher numbers than in seasons. The dates on which Chiffchaffs in the north and west. any previous year. The positive results arrived back in the UK have advanced Throughout the summer (June for both of these species were driven by by two weeks since the 1960s, possibly to August), rainfall totals were above particularly large increases in numbers as a result of climate change, leading average in every month and mean in the north, the region in which to them breeding earlier. It is possible temperatures were at or above average; breeding was least impacted by weather that this change in the timing of their June 2017 was the equal fifth warmest during the previous season. breeding has coincided with similar and the sixth wettest June since records Adult survival rates, as monitored advances in the availability of their food began in 1910. through CES, declined significantly resource, contributing to the dramatic

4 – LIFECYCLE Spring 2018

2017 breeding season results | ANNUAL RESULTS

↓ ↓ ↓↓ ↓↓↓

↑ ↑↑ Table 1. National and regional CES results for 2017. For long-term↑↑↑ trends, indicates an increase of <25%, of 25–50% and of >50%, while indicates a decrease of <25%, of 25–50% and of >50%. Percentage changes from the five-year means (2012–16) are also reported for 2017, with significant decreases shown in red and significant increases in blue. ‘*’ denotes a small sample size. Sample sizes are currently not large enough to allow regional survival trends to be produced. See CES website for map of regions.

ADULT ABUNDANCE ADULT SURVIVAL PRODUCTIVITY 2017 vs 1985–2017 2017 vs 2012–16 1985–2017 2012–16 1985–2017 2017 vs 2012–16 Migrants National North East West National North East West

↓ ↓↓↓

Chiffchaff 19 43 17 4 -23 ↑ -5 -35 0 22 ↑↑ ↓ ↑↑↑

↓↓ ↑ Willow Warbler ↓↓↓ 5 9 -19 24 -13 -17 -18 6 -29

Blackcap -8 -8 -4 -14 ↓ -28 27 17 14 64 ↑↑↑

Garden Warbler ↑↑ -20 -14 -18 -30 -27 21 4 17 37 ↑↑ ↑ ↑↑↑

↓ Lesser Whitethroat* -11 -44 -10 0 -45 ↑↑ -24 -29 -11 -50 ↑↑

↑↑↑ Whitethroat -9 -4 -10 -9 -35 ↑↑ 3 -11 -1 25

Sedge Warbler -2 -9 5 -4 ↓ -6 -3 -29 7 0 ↓ ↓↓

Reed Warbler ↑ 5 49 2 6 -16 -1 -34 1 3

Tits ↑↑↑ ↓ ↓↓

Blue Tit -12 2 -16 -20 ↓ -24 53 0 68 108 ↑↑

Great Tit ↓↓ -10 9 -14 -34 -2 35 -1 41 120 ↑↑↑ ↑↑↑

↓ Willow Tit* -40 -39 -50 81 - - ↑ 36 22 95 -

Long-tailed Tit 0 -4 0 4 ↑ -7 19 32 6 38

Other residents ↑↑ ↓↓↓

↓↓ Cetti’s Warbler* 11 154 23 -4 - - ↑ 28 - -10 103

Treecreeper* 29 23 33 42 - ↓ - 1 -9 11 -17 ↓↓

Wren 8 32 1 3 -32 ↑ -11 -37 -4 1 ↑ ↑

Blackbird 2 11 -2 4 ↓ -7 0 -8 -11 21 ↑ ↑ ↓

Song Thrush 6 17 4 -4 ↑ 24 11 53 5 -3 ↓↓ ↑

Robin 16 18 17 8 ↓ -26 -10 -13 -19 14 ↑ ↑

Dunnock 0 3 0 -5 ↑ -20 3 5 -5 19 ↑ ↓↓

Chaffinch ↑ -44 -37 -50 -59 -37 65 101 -17 30 ↓↓ ↑

Bullfinch 14 26 13 3 -12 ↑↑↑ 18 32 11 -2 ↑↑ ↓↓↓

↑↑ Greenfinch ↓↓↓ -52 -58 -46 -56 6 68 135 52 35

Goldfinch -7 -7 -5 -10 - - 17 65 -19 48 ↑↑↑ ↑↑↑

Reed Bunting -7 -10 -8 -1 ↓ -4 -7 -35 -19 42 rise in numbers of almost 300% in the was minor, and had little impact on rates have increased since 2012. In last 35 years. the stable long-term (1990–2017) contrast, results for Nightingale suggest Migrant species monitored through trend, whereas the decline for Swift a considerable drop in survival rates in RAS also exhibited mixed fortunes was more dramatic. Swift survival 2017, with the trend now at its lowest in 2017. The apparent survival rates rates are now far lower than they have point since RAS monitoring began on for House Martin and Swallow been in previous years, though as only this species in 2011. increased in 2017; results for both one site currently contributes to the species have fluctuated over the past trend we cannot assume this reflects Migrant productivity few years, although the long-term the national situation. Pied Flycatcher, Results from NRS indicate that it was trends (1994–2017 and 1998–2017 Whinchat and Wheatear survival rates a significantly early breeding season in respectively) remain reasonably stable. all increased slightly in 2017, with a 2017 for most migrant species (Table Conversely, both Sand Martin and greater increase exhibited by Tree Pipit; 2). Sand Martin laid 12 days earlier Swift survival rates fell in 2017. The the long-term trends are relatively stable than the five-year mean. An increase decline in Sand Martin survival rates for all but Tree Pipit, for which survival in clutch and brood sizes appeared to

Spring 2018 LIFECYCLE – 5 ANNUAL RESULTS | 2017 breeding season results

Some comments that accompanied CES submissions illustrate that it was a mixed breeding season across the country:

Swallow, by Mary Michael Patterson/BTO “Thankfully, it’s been one of the better years, just creeping into the top 10 out of 30. Good numbers of adults and breeding success was quite good. Plenty of tits around, Dunnocks look like posting a record year but not so good for Robins and Bullfinches – both well down on numbers. Willow Tits have never come back after being wiped out by the winter of 2012/13 which is a shame. Some nice species in there such as the Nuthatch and Fewer Swallows fledged per breeding attempt in 2017 than in any previous year since Lesser Pecker.” Dave Hazard, South NRS monitoring began. Yorkshire

“The year started so well but went compensate for low egg-stage survival, and Garden Warbler; as numbers of downhill from June when bad wet possibly resulting from the wet summer both of these species were significantly spells probably accounted for many conditions and the number of fledglings reduced in 2017, it is possible that the nests and young. Generally, migrant per breeding attempt (FPBA) was close increase in productivity was a result species seem to have done even to the average. Swallow was one of the of density dependence, where fewer worse than last year.” David Leat, migrants hit hardest in 2017; despite birds competing for resources results Northumberland laying five days earlier in 2017 and in increased breeding success. Blackcap recording a significant increase in clutch productivity was especially high in the “The year started slowly with low size, it exhibited the highest chick- west of Britain. By contrast, Willow numbers of adults but it has picked stage failure rate and the lowest FPBA Warbler productivity fell in 2017; NRS up as the year went on and we have since NRS recording began; again, wet data show that this species experienced finished with equal second highest weather is likely to have contributed to significantly reduced clutch and brood in last 25 years. Especially high this poor performance. sizes during the 2017 season. numbers of juvenile Chiffchaffs and Chiffchaff and Reed Warbler, Willow Warblers, but Reed Warblers the two migrants to be recorded in PASSERINES AND NEAR-PASSERINES and Sedge Warblers down.” Lynne significantly higher numbers than Resident abundance and survival Lambert, Hertfordshire normal through CES, both laid 10 Although the winter of 2016/17 days earlier than the five-year mean; for was, for the most part, dry and mild, “We had a reasonably good both, this was the earliest average laying more resident species exhibited year but we missed two visits due date recorded. BirdTrack data confirm significant declines than increases in to inclement weather. Most resident that arrival dates for both species were abundance in 2017 (Table 1). Fewer species seem to have done particularly also earlier in 2017 than the historical adult Chaffinches and Greenfinches well but warblers appear to have been average. Spotted Flycatcher, Pied were recorded by CES participants less successful. The highlight of the Flycatcher and Blackcap also registered in 2017 than in any previous year, year was retrapping a Cuckoo that laying dates earlier than average in 2017 with Chaffinch also recording its we ringed during a CES visit in 2013. but none of these warbler and flycatcher lowest survival rate since CES began; Although there were still four pairs species exhibited a significant change the productivity declines exhibited of Turtle Doves breeding within our in FPBA. Indeed, CES results indicate by both during the previous season ringing area, we failed to catch any that it was a relatively average year for may have contributed further. The this year.” Simon Lane, Hampshire productivity, with only three migrants long-term trends for these finches are displaying a significant change. also indicative of significant declines, Productivity was increased for Blackcap mirroring the dramatic declines shown

6 – LIFECYCLE Spring 2018 2017 breeding season results | ANNUAL RESULTS

Table 2. Laying dates and breeding success calculated from 2017 NRS data. Laying dates are given as the number of days earlier or later than the five-year mean (2012–16); productivity figures represent a percentage change relative to the five-year mean. Statistically significant ‘positive’ and ‘negative’ changes are highlighted in blue and red respectively. ‘*’ denotes small sample size (<25 records).

Species Laying Clutch size Brood size Egg-stage Chick-stage Fledglings date (days) (%) (%) survival (%) survival (%) produced (%) Migrants Sand Martin -12.0 3.6 5.9 -4.3 -1.6 -0.3 Swallow -4.8 1.6 -0.7 -1.1 -11.0 -12.6 Chiffchaff -9.5 3.6 5.2 3.1 3.9 12.7 Willow Warbler -1.1 -6.3 -4.4 11.5 -5.0 1.2 Blackcap -5.6 -0.8 -1.1 3.3 -15.9 -14.1 Reed Warbler -9.5 1.9 2.0 -2.1 -0.9 -1.1 Spotted Flycatcher -6.0 -2.3 2.9 3.6 -8.5 -2.4 Pied Flycatcher -4.8 4.8 4.3 1.6 -3.5 2.1 Redstart -1.6 4.5 7.8 6.5 -11.0 2.3

Tits Blue Tit -10.4 5.7 6.9 1.3 3.2 11.9 Great Tit -8.6 2.4 5.0 1.2 4.0 10.5 Long-tailed Tit -5.2 -1.1 -8.5 2.5 5.6 -0.9

Other resident passerines Jackdaw -2.6 5.2 -1.0 1.3 4.5 4.8 Nuthatch -4.3 2.4 3.8 0.0 1.8 5.6 Wren -1.8 -4.8 -2.5 2.0 -0.7 -1.3 Starling 2.4 -7.4 4.4 0.8 3.3 8.7 Dipper -2.8 -1.9 -4.9 -1.4 8.1 1.3 Blackbird -8.3 -4.7 -3.2 -5.8 -2.5 -11.1 Song Thrush -9.8 -2.8 -3.1 -3.9 1.1 -5.8 Robin -4.3 -1.9 -2.1 3.5 -3.9 -2.6 Stonechat -5.0 -1.0 0.3 -4.3 -3.7 -7.5 Dunnock -4.4 -3.2 3.4 -0.1 20.1 24.2 House Sparrow -0.9 -0.4 2.5 -1.5 1.6 2.5 Tree Sparrow -2.6 0.9 0.5 0.1 -4.2 -3.7 Grey Wagtail -3.2 -2.8 2.2 -4.9 -8.5 -11.1 Pied Wagtail -3.6 -0.7 -0.4 -6.1 2.4 -4.3 Meadow Pipit -2.8 0.9 -3.1 -25.2 -19.8 -41.8 Chaffinch -3.0 -2.5 -1.0 3.7 2.5 5.2 Linnet -7.7 -1.0 -3.0 -9.6 0.4 -12.1

Resident non-passerines Stock Dove 0.6 3.7 -0.5 -1.1 6.2 4.4 Woodpigeon -8.5 1.6 1.9 -17.1 7.6 -9.0

Owls and raptors Barn Owl -19.4 2.9 -3.6 -0.6 0.2 -4.0 Little Owl -6.2* 4.8 1.3 -4.6 11.6 7.9 Tawny Owl -3.2* -4.2 -0.9 4.4 0.8 4.3 Kestrel -4.1 2.8 4.5 2.7 1.8 9.2

Waterbirds Moorhen -9.1 -0.8 3.5 -10.3 -34.2 -38.9 Coot -4.6 -10.2 4.3 -39.6 8.0 -32.0

Spring 2018 LIFECYCLE – 7 ANNUAL RESULTS | 2017 breeding season results

Linnet, by Allan Drewitt/BTO Kittiwakes, by Jill Pakenham/BTO; Barn Owl, by Robin Lee/BTO; Barn Owl, by Robin Lee/BTO; Jill Pakenham/BTO; by Kittiwakes,

Puffin Barn Owl Starling

Razorbill Little Owl Linnet

Kittiwake Sand Martin Twite

Figure 1. RAS survival trends. Survival is measured from the year indicated on the graph to the following year: i.e. the figure for 2016 is the survival rate from 2016 to 2017. The dotted lines show the upper and lower 95% confidence limits about the modelled estimate.

8 – LIFECYCLE Spring 2018 2017 breeding season results | ANNUAL RESULTS

through BBS monitoring since the mid- Thrush and Blue Tit representing the RAS ringers also had a mixed year 2000s that have been largely attributed earliest on record for these species in 2017: to the persistent impacts of finch (Table 2). Advanced laying may have trichomonosis. contributed to the successful breeding “It turned out to be an epic RAS Numbers of Blue and Great Tits season experienced by both Blue Tit season for me, with a big increase were significantly lower in 2017, and Great Tit, which fared particularly in the number of adult and juvenile most notably in the south. This again well in the west, driven by increases Starlings. The dry spring almost could be a legacy of poor breeding in clutch sizes and reduced egg-stage certainly played a big part in the performance in 2016, although it is failure rates. Long-tailed Tits also increase, with natural food being possible that the frosts in the second bred significantly earlier than average, harder to come by. I had over 75 half of April reduced the food available and CES results indicate an increase different adults in the garden on 15 for tits. Blue Tits and Chaffinch in productivity for this species too. May alone, with 69 being colour- populations may also have been affected CES data are indicative of significant ringed birds and just six new adults.” by high overwinter mortality, with both increases in productivity for Chaffinch, Peter Alker, Starling RAS, Greater exhibiting a significant decline in their Greenfinch and Bullfinch, all driven Manchester survival rate in 2017. by results in the north. Both Chaffinch Treecreeper, Robin and Bullfinch, and Greenfinch were recorded in lower “Good season here. I caught 98% alongside Chiffchaff, emerged as numbers than ever before, suggesting of the parents of individual nests and, winners from 2017, all increasing that density-dependent factors might be since many were double-brooded, I significantly in abundance; Treecreeper the mechanism underpinning increases rather think that literally only one or numbers are now at their highest since in breeding success; Bullfinch, however, two adults escaped without being CES began. Given that 2016 was a was recorded in significantly higher captured at all; maybe none. Not poor breeding season for Robin and numbers in 2017. that I’m addicted, or anything!” an indifferent one for Treecreeper and Although a number of resident Tony Martin, Sand Martin RAS, Bullfinch, and that adult survival was species exhibited significant declines in Cambridgeshire generally below average, improved clutch and brood size, the only species first-year survival is the most likely to record a significant reduction in “On some days I have a Potter trap explanation for these observations. FPBA was Meadow Pipit, for which permanently set in my garden. Result RAS results demonstrate a large productivity was the lowest on record. this year: c. 100 Starlings, more tits increase in the survival rate for Dipper Robin and Wren productivity also fell and Dunnocks than you can shake a in 2017, with the rate now as high as in 2017; NRS data indicate that the stick at, but no sparrows.” Ray Morris, it has been since monitoring began in average clutch sizes of the latter hit an House Sparrow RAS, Kent 2002, but a large decline for Hawfinch, all-time low. with the rate now at its lowest point. “A very poor year, with very few For the third year in a row, the House birds locally, which seemed to fledge Sparrow survival rate increased, whilst very few nestlings. I have had one Starling rates increased for the second bird reported shot locally, which I’m consecutive season. Following a period hoping is an isolated incident. On a of decline, the addition of data from positive note, it does seem that nearly a second RAS project led to a small Great Tit, by Sarah Kelman/BTO Tit, by Great all the adult Starlings on the small increase in the Twite survival rate in estate where I live have blue darvic 2017, and the long-term trend remains rings on.” Derek Gruar, Starling RAS, stable. Jackdaw and Linnet survival Bedfordshire rates exhibited a small decline in 2017; however, again, the long-term trends “My Swallow population is only just for both species are stable. Despite a recovering from two to three years of decline in 2017, the long-term results intense predation by Magpies (with show an increase in the survival rate for assistance from the odd mouse!); Stonechat. ironically their saviours are three new cats on the yard...!” Richard Facey, Resident productivity Swallow RAS, Glamorgan As was the case for migrants, laying dates were significantly earlier for Great Tits (and Blue Tits) had a successful many resident species; those for Song breeding season in 2017.

Spring 2018 LIFECYCLE – 9 ANNUAL RESULTS | 2017 breeding season results

OWLS AND RAPTORS Many NRS participants reported a After a disastrous breeding season in rain-affected season in 2017: 2016, Tawny Owls bounced back in 2017. The RAS trend shows that “For my Blue and Great Tit boxes the apparent decline in survival rate productivity was the highest ever for calculated through RAS from 2015 MacArthur/BTO Jamie by Tern, Arctic pulli ringed and after fledging the to 2016 was far less severe than was trees were full of roving tit flocks. indicated in the 2016 results, a result of However the flocks soon thinned out birds not being detected because they and were few and far between by had suspended breeding; re-encounter mid-summer. At the end of 2017 my of these birds in 2017 allows the 2016 retraps of fledged Blue Tit pulli was 16 figures to be adjusted. The much- individuals from 132 pulli ringed – the improved breeding season in 2017 led lowest return at 12% for the past eight to an increase in the apparent survival years.” Phil Deacon, Wiltshire rate, which is now as high as it has ever been. This trend is calculated from a “A lot of heavy rain caused most single project, so does not necessarily A RAS trend for Arctic Tern was produced of the Red-throated Diver nests to reflect the national picture. for the first time in 2017. be flooded. Only those on lochs with The survival rate for Barn Owl and relatively small catchment areas and/ Little Owl also increased in 2017. NRS or good outflows survived. A number data indicate that the laying dates for west coast; the long-term trend for this relaid, but the chicks disappeared both species were significantly early species is stable. soon after hatching: lack of small compared to the five-year mean (Table Although there are now four sandeels?” Chris Reynolds, Isle of 2) but that Barn Owl brood sizes were RAS projects on Mute Swan, only Lewis significantly reduced; neither exhibited one has been running long enough a reduction in FPBA, however. Kestrel to contribute to the results and a “This has been the most productive brood size increased in 2017, as did trend was produced for the first time year for the Blue and Great Tits since both brood and clutch size of Peregrine in 2017; while there was a slight I started monitoring the nest boxes although, again, FPBA was average for decline in the survival rate in 2017, in 2007. The large nest boxes have both species. the long-term trend is stable. A trend also been successful, particularly was also produced for Arctic Tern for for the Tawny Owls, Kestrels and SEABIRDS AND WATERBIRDS the first time in 2017 and the results Stock Doves.” Ian Wrisdale, RAS trends were produced for eight show a decline in survival between Northamptonshire seabird species in 2017. The apparent 2016 and 2017, possibly caused by an survival rate for Kittiwake continued outbreak of botulism in the only colony “It was a poor breeding season to show a decline and it is now at its contributing during the 2016 summer. in West Lothian, hampered by bad lowest point for 10 years. The survival The detail in this overview and the weather and a lack of insects.” Chris rate for Eider increased slightly in accompanying tables demonstrates Laurie, West Lothian 2017, though note that results for the incredible amount of information the past 10 years are generated from a supplied by nest recorders and ringers, “A very mixed year for me here single east-coast population and may monitoring changes in fortunes of in Northumberland (and not good not reflect the national situation. The bird populations over time and, vitally, in Mid Wales, where Pied Flycatcher Puffin survival rate remained constant identifying the causes. As ever, we’d chicks were dying as I visited nests between 2016 and 2017, although be very pleased to hear from anyone in early June due to prolonged – ie the long-term trend is suggestive of wanting to participate; email ces@bto. 36–48 hours continuous – heavy a slight decline, while survival rates org, [email protected] and [email protected] rain). Similar continuous and heavy of Guillemot, Razorbill and Shag all respectively for more information. rain here in early and late June saw declined. The Guillemot and Razorbill many first-brood Swallows desert trends are generated solely from west- Further results from the 2017 season can and their second attempts also coast projects, and both species are be viewed on the BirdTrends website: failed three weeks later.” Peter Rose, also demonstrating a slight long-term www.bto.org/birdtrends Northumberland and Wales decline in survival. The Shag trend combines historical data from two The full suite of 2017 RAS results can be east-coast projects with one from the found at www.bto.org/ras-results

10 – LIFECYCLE Spring 2018 Chiffchaffs and Willow Warblers | FIELDWORK

First come, best served?

For migratory birds, the timing of key life-history events is associated with the distance individuals must travel to reach their spring breeding grounds. Long-distance migrants tend to arrive at their spring breeding grounds later than species that make shorter migratory

journeys, and these differences Chiffchaff, Chiffchaff, colour-ringed by Alex Berryman in timing of arrival could have important consequences. These potential consequences became the subject of Jenny Donelan’s MSc study at UEA.

Birds were caught using a mist net set along a woodland path in the bird’s territory; sound lures were used for 10 minutes to catch the males, while females were caught by chance.

During the spring and summer of of males and calls of females. It was well when flying with a big feather in 2017, I undertook fieldwork for my important that I standardised my their beak!) and following them back to MSc dissertation project to investigate sampling effort because this would the nest. Females are very vocal when the consequences of spring arrival allow me to pick up any patterns collecting feathers, which helped a dates for the breeding phenology of occurring in the woodland that season, lot. Once a nest was found I recorded migratory warblers. I asked myself, do and over subsequent seasons if I or its progress and the bird’s subsequent individuals arriving early breed earlier? anyone else were to continue the project nesting attempts. Do they gain access to higher-quality using the same methodology. The findings showed that, in breeding territories? And, if first nesting Once a new bird was found, I general, i) early-arriving males occupy attempts are unsuccessful, are early recorded the exact location of that specific habitats within the woodland, arrivals more likely to re-nest? individual and their date of arrival, which may reflect territory quality, and My study focused on Chiffchaffs and attempted to catch and colour ii) early-arriving individuals do pair and (short-distance migrants) and Willow ring them. Colour-ringing allowed me nest before later-arriving individuals. Warblers (long-distance migrants). to know precisely which individuals This is likely to mean that should those Chiffchaffs and Willow Warblers are arrived when, and allowed me to relate early pairs fail, they should have more closely related and share extremely arrival date to habitat occupancy and time to re-nest, while late-arriving birds similar nesting behaviour and habitat the timing of pairing and nesting; it also may not have this option. My project usage. These two species therefore allowed me to monitor the movement therefore provides an example of the provide an ideal system to measure and of individuals across the woodland. value that systematic recording of the compare the consequences of different I collected pairing data by following number and location of individuals migratory strategies. Specifically, I colour-ringed males and classing an as they take up territories can add assessed whether the spring arrival dates individual as paired once I had observed to a traditional colour-ringing and of the two species influenced habitat them mate-guarding a female. I nest-monitoring study. These findings occupancy, pairing and nesting dates. subsequently monitored paired birds to are currently being prepared for Over a period of four months determine when females began nesting. publication. (March to June) I surveyed the Norfolk I attempted to find nests before, or I would like to thank the Norfolk Wildlife Trust’s Foxley Wood Nature during, egg laying as this allowed me Wildlife Trust, all the volunteers that Reserve for newly arrived Chiffchaffs to calculate the precise clutch initiation helped me during fieldwork and my and Willow Warblers. I walked along dates for these nests and relate this to university supervisory team, Prof Jenny pre-defined woodland paths for a individual arrival dates. Gill, Dr Catriona Morrison and Dr minimum of five hours a day for six I found most nests by watching Iain Barr for their advice and guidance days a week, listening for the songs females pick up feathers (they stand out throughout.

Spring 2018 LIFECYCLE – 11 MONITORING | Swallows Swallow, by Liz Cutting/BTO Swallow, by Liz

“Retrapping ‘my’ adults fresh back from Africa has been a real highlight for me”. Michael Miles

Swallow survival: plugging a gap

One of our most-ringed migrants, the Swallow, is a familiar bird whose appearance heralds the start of summer to many people in Britain & Ireland. In this article Declan Manley, Michael Miles, Geoff Myers, Hugh Pulsford and Jan Riley share their knowledge and expertise on ringing and nest recording this iconic species.

Swallows are one of the few long-distance survival trends is therefore limited. Five RAS migrants to display a positive population projects are currently helping to plug this trajectory, with numbers increasing by gap (one in the Republic of Ireland, one in 50% between the mid-1980s and 2010, Wales, one in western England and two in resulting in the species’ removal from the northern England). These, together with UK Birds of Conservation Concern Amber three historic studies, enable us to produce List. The last five years have witnessed a reasonably robust survival figures back to change in fortunes, however, with numbers the late 1990s but more data would be dropping sharply. The species is well covered very welcome, particularly given the recent by the Nest Record Scheme, with between declines; email [email protected] if you think 2,500 and 3,000 nests monitored annually; you could help. analyses suggest that productivity has been stable over this period. The ringing totals are SELECTING A STUDY SITE equally impressive, amounting to c. 40,000 Swallow breeding populations tend to be individuals a year, but fewer than 10% are aggregated, as suitable nesting habitat is adults and over half of those are caught at limited. Farm buildings typically form roost away from the breeding grounds. good focal areas but it is unlikely you’ll As the BTO Swallow Roost Survey find a complex big enough to support a showed, roost catches can be useful to breeding population large enough to meet explore elements of Swallow ecology, such the RAS criteria (obtaining 30 adult–adult as fattening strategies (Coiffait et al. 2011), recaptures per year). The key to site selection REFERENCE but they are of limited use in generating is to choose areas that are self-contained, Coiffait, L. et al. (2011) survival data. Figures from one of the encompassing all the suitable locations Fattening strategies of authors of this article show that 24 retraps in the immediate vicinity. In this way, British & Irish Barn Swallows and 36 controls have been generated from you maximise the chance that a bird not Hirundo rustica prior to 8,301 Swallow captures at roost, compared encountered in a given year is dead, rather autumn migration. Ringing to 36 retraps from 83 encounters of than merrily raising a brood on a barn next & Migration 26, 15–23. breeding birds. Our knowledge of Swallow door that you don’t have access to, which in

12 – LIFECYCLE Spring 2018 Swallows | MONITORING

turn increases the accuracy of the survival fly straight into the net, even though they TOP TIP rate generated using your data. Combining can see it. Trapping can be particularly Including dog biscuits multiple self-contained sites under the effective as birds exit from doorways or in your ringing kit will banner of a single RAS is not a problem, windows, and a hand-held net may present enable you to befriend but the closer they are to each other the an easier option in some situations (this most farm dogs! better (close enough to exchange birds approach can work well on stable doors between seasons would be the ideal) as the when the bottom door is closed, for environmental pressures, such as weather example). and food availability, faced by each group of Mist nets should always be set with birds are therefore likely to be similar. plenty of bag as Swallows get up quite a speed and tend to bounce out of a very CATCHING FREE-FLYING BIRDS taut net. They are famously easy to extract, One of the best times within the nesting having short legs that they hold close to cycle to catch adult Swallows is when the body when captured, typically lying they are feeding chicks, as both birds motionless in the shelf. Patience is required are at their most active; males are less to catch Swallows as it can take time; frequently encountered when the females however, they are a very tolerant species and are incubating as they tend to stay outside, are not easily disturbed, as one might expect but both sexes can also be caught safely at from a bird that frequently nests close to this stage. Ringing adults throughout the humans. If birds are trying to get back to nesting cycle extends the catching period, the nest, but are put off by the net, it is however, providing more opportunities to best to take it down after 20–30 minutes to catch as many of the adults as possible. It is allow the chicks to be fed. possible that both parents will roost near the nest, so setting a net outside at dawn often PULLUS RINGING AND NEST RECORDING works well, but Swallows can be caught at Ringing pulli can easily be combined with any time of day; if they have small chicks, catching adults and if both are undertaken starting after 10 am will ensure that their simultaneously you maximise the chances offspring have been well fed. Mist nets work to collect valuable data on site fidelity well to catch both adult birds and fledglings. and recruitment. A good-quality ladder is To identify the ideal positioning, watch the invaluable when ringing but a mirror on the birds’ flight lines as they move in and out of the buildings as these tend to be very repeatable. You may need to set up inside sheds or stables, so multiple short mist nets may be of more use than a few longer ones. Attaching guys can be tricky, but sometimes the poles can be jammed against the rafters or roof. Alternatively, if the farmer allows, screwing cup hooks into walls or posts works well. If there is no Wood chicks, by Eric Swallow nest with large other option, heavy artefacts such as troughs or pallets, are useful to guy to or to prop against the pole. If you can, leave a helper outside while you are setting nets, standing a distance away but near enough to stop the birds going in while you set; if it is possible to position the net without the birds knowing you have been inside the building, they often go straight in without looking. If setting outside the building, leave a gap of about one metre at one side; the birds soon find the way in and tend to get caught When approaching a nest for the first time, if the chicks are peering over the on the way out, although occasionally, they rim, they are too big to ring and should be left alone.

Spring 2018 LIFECYCLE – 13 MONITORING | Swallows Swallow chick, by Jan Riley; artificial nest cups, by Hugh Pulsford Swallow chick, by

Artificial nest cups can be made by moulding a mixture of fine sawdust and cement powder, mixed in an approximately 50:50 ratio, with water added until it is the consistency of bread dough, over the inside of a half-sphere of c. 18 cm in diameter (plastic hamster balls work well, apparently!). Apply a thin layer of Vaseline, and then add a layer of the nest mixture 1.5 cm thick. Once dried, the mould can be removed and the artificial cup sawn in half to make two nests.

end of a telescopic pole, or a mobile phone obscured, it is best to put them all back in on the end of a long ‘selfie stick’, can be a the nest simultaneously, heads down, facing great help when wanting to examine nest towards the wall. Put a bag over the top of contents at earlier stages of the nesting cycle. them and gently hold it down for several As with most passerines, the optimal minutes until they settle. time for ringing is when the flight feathers Swallows typically have two broods, are just starting to emerge from the pin (the but the adults move to a different nest, first day they would be coded as ‘Feathers invariably an existing old one, usually Short’ (FS) on a nest record); in Swallows within a few feet of the first; very this typically occurs at eight or nine days occasionally, the same nest is used twice. old. They are easy to handle at this stage Refurbishment of an existing nest, if carried and there is still plenty of space in the nest out at all, is generally limited to the addition cup, which makes them easy to extract and of 10–15 mm of fresh mud to the top of place back inside with no risk of forced the nest wall. Young that fall out of nests fledging. Swallow pulli are very tolerant, can be replaced; if it is unclear which nest however, and can be ringed as soon as the it has fallen from, relocating it to a nest leg is sufficiently developed to stop the ring containing pulli of a similar age and size is sliding off the tarsus right up to the latter usually successful. stages of ‘Feathers Medium’ (FM) (generally HORSE HAIR 5 days and 13 days old respectively, though ARTIFICIAL NEST CUPS If nests are located in be aware that growth rates vary according Occasionally, Swallow nests can be areas with horses, one to weather conditions, availability of food positioned in inconvenient places, such hazard to be aware of and degree of sibling competition and as above a water trough or over expensive is horse hair, which can judgement should always be based on the equipment that can be damaged by their be used in place of the visual evidence at the nest). This flexibility droppings. It might be possible to encourage more typical grass and can be very useful when visiting large these birds to relocate by placing an artificial feather lining. As the colonies as breeding attempts may not be nest cup in a more suitable part of the chicks grow, they can synchronous. building. Attach the cup to a back board become hopelessly Large chicks will sometimes leave the using exterior glue and drill the board in tangled in it, making nest if approached, but they rarely exit the position. Most Swallows will add a further it tricky to remove building and, if flying, will return when left thin layer of mud to the inside of the cup them to ring and alone. If you find yourself in the position before lining the nest. Another benefit of impossible for them to of ringing larger chicks, which can happen artificial nests is that they are slightly larger fledge without human occasionally as the age can be difficult to than natural ones and won’t disintegrate intervention. estimate prior to handling if the cup is part whilst holding five large pulli!

14 – LIFECYCLE Spring 2018 Nest finding| FIELDWORK Scottish moors, by Jonathan Groom Scottish moors, by

Whilst it was great to find the nests of some quite scarce species on the Scottish moors, the significance of how rare nest records are for some of these species was sadly lost on me at the time.

Novice to mentor: a nester’s journey

Jonathan Groom has been passionate about wildlife and birding for as long as he can remember, particularly surveying and monitoring. He developed this interest after undertaking Bird Atlas surveys, knowing that his records contributed to large-scale research projects. Here, Jonathan explains how he got involved in the Nest Record Scheme and why he finds contributing to NRS, and mentoring others, challenging, thrilling and hugely interesting.

I was firstintroduced to the Nest Record it certainly feels like it when I think how Scheme during 2011 and joined up in much has changed since then. My work 2013. I would consider myself to be self- in Scotland (with another well-known taught, in that I was never really formally ornithological charity) involved finding introduced to the scheme. I was given a Golden Plover nests; as a result of tramping fantastic career opportunity to carry out remote Scottish moors, my first three self- field research in Scotland that sparked found nests were Red Grouse, Meadow the interest and showed me a side to Pipit and yes, a Golden Plover (I can’t quite birding that I had not experienced before. remember what order they were). This I was then able to fill in the gaps myself was followed by Teal, Hen Harrier (which with guidance from the various fantastic was passed to a Raptor Study Group for resources that are now readily available to monitoring) and Willow Warbler. all nest recorders. I have also been able to One of my colleagues encouraged share my passion, and what knowledge I us to collect grid references as they were have accumulated, with a few others during completing nest record cards. This planted the last couple of years as a mentor, and it the seeds in my mind and eventually, during has been an amazing feeling to see how they another season of Scottish fieldwork in have grown to love it too. One of them has 2013, I signed up for NRS myself. I got now become my nest-recording colleague, a copy of BTO’s landmark publication, A and together we inspire and support Field Guide to Monitoring Nests, the content each other through each season, making of which I devoured hungrily. I had grand the whole experience even better and ideas that year, but even though you can highlighting how important this individual read all you like, sometimes it just doesn’t support is to NRS. come to you all that quickly. I remember trying to tap for Whinchat and being MADE ON THE MOORS soundly defeated. I saw the fledglings later It all began back in the mists of time during on and realised that I had been way off! 2011. OK, that’s not so long ago really, but This has remained a ‘bogey’ nest for me

Spring 2018 LIFECYCLE – 15 FIELDWORK | Nest finding

ever since. But being in Scotland, my luck take every opportunity to talk birds. I did continue and I managed to record subsequently invited him to join me nesting Snipe, Lapwing, Common Sandpiper, in 2015. I was well prepared and got started Pied Wagtail, Swallow and of course, more early with a couple of new species for me, Meadow Pipits. I realise now just how Long-tailed Tit and Magpie, for which I fortunate I am to have found some of these, enlisted Dave’s help to check the nests. and it was really quite a strange start to my Dave has a massive sense of enthusiasm nesting journey, as I had still yet to record and delight in discovering and learning the ‘basics’ such as Robin, Blackbird, Wren new things. One of his earliest nesting or Song Thrush. experiences was helping me check a Magpie nest, by lugging a heavy wooden ladder BACK TO BASICS some distance along a footpath, followed My journey then took me to the somewhat by some precarious balancing and leaning less wild lands of the West Midlands in with a mirror on a stick to get some pretty 2014, where I settled with a new job in sketchy views! We also found a Long- Shropshire. I was determined to continue tailed Tit nest suspended in brambles over nesting, as well as signing up for local BBS, a steep stream bank, which we somehow WBBS and WeBS surveys. managed to access by forming a two-man It was a slow start for me as I was human chain along the edge of the bank, still exploring my new surroundings, but and inserting a ‘pre-historic’, non-digital I finally managed to connect with the endoscope that I borrowed from work into commoner species and even found a great the nest (I of course fell in the stream on spot for Linnets, which allowed me to one visit, much to both our amusements). practice my tapping skills on something a Despite this rather unorthodox start, in little more straightforward than Whinchat. Dave’s own words: “a bit of precarious I also discovered the Nest Record Forum, balancing just to get a glimpse of the eggs. That an excellent resource for learning from rush of adrenaline and I was hooked!” To this knowledgeable members of the scheme, day, this remains his favourite nest. a way to share your experiences and read I certainly didn’t waste any time in 2015 about the adventures of others. as I also helped with a project which set up Through my new job I befriended a a successful Pied Flycatcher nest box scheme chap called Dave, with whom I would and started checking some Barn Owl nest Golden Plover nest, by Jonathan Groom nest, by Golden Plover

The

16 – LIFECYCLE Spring 2018 Nest finding| FIELDWORK

boxes for a local group. Dave and I ended up having a respectable year, with around 50 nests each, in addition to the nest boxes. Dave proved to be a natural nester, putting in the hours and establishing his

own very productive site on family-owned Jonathan Groom Stonechat nest, by land on the Welsh border with some lovely wooded hillsides. We continued to learn a lot together and during the next two years threw ourselves wholeheartedly into nest recording. We improved our ‘tech’, purchasing proper endoscopes, a range of mirrors of all shapes and sizes, extendable poles and biodegradable marking tape, and I even printed us bespoke notebooks with nest record cards on each page. We came close to 100 nests each in 2016 and then both achieved that milestone in 2017. We hit our 606th nest and 57th species Our first Stonechat nest – the result of patience, teamwork and expert advice. between us by the end of 2017, including such ‘goodies’ as Willow Tit, Spotted Flycatcher and Wood Warbler. We also teamed up to help mentor two volunteers fact that many people, quite rightly, would who took on the monitoring of the Pied be nervous about approaching nests and Flycatchers from 2015 and they are working causing the birds to desert. As nesters, we up from checking nest boxes to becoming know that when it’s done properly, the full nesters as well! risks are minimal; and just providing that reassurance and reminders on the NRS MENTORING Code of Conduct will again be of great help So why be a mentor? I think, purely in for the new starters. terms of looking at the data, even just Perhaps the biggest take-away from our one new NRS member can make a huge nest recording is that Dave and I both felt contribution. Looking at the online NRS that it has increased our understanding of report, I can see that 850 nest records were birds enormously. Not just what they look submitted for Shropshire in 2016. One and sound like, but how they behave, what STONECHATS extra person could easily contribute 50 more different calls mean and how they use the The 2017 season records, which is a substantial increase. If structure and features of their habitat. It culminated in Dave they were to concentrate on a species that also makes common birds like Wrens and and me staking out receives few annual records, then huge Blackbirds, likely often overlooked by many, a Stonechat pair and differences can be made. Some of these interesting and exciting again. using patience and species are actually quite common, for I can’t recommend being a mentor teamwork (and the example only 22 Goldcrest nest records and enough, not just because you’re helping expert advice of a 49 Treecreeper nest records were received in to collect more data for NRS, or because prominent member 2016 for the whole of the UK. you’re introducing people to a fantastic of the Nest Record Having a mentor also makes a huge new experience, but also because you’ll Forum) finally tracking difference to how quickly a new starter get such a great deal of satisfaction from it it down to find our first can get up to speed. As my own example yourself. There’s nothing quite like seeing nest for the species. illustrates, even though there is a wealth of the excitement of someone finding their It was a ‘high five’ knowledge available to read, this only takes first nest, or seeing someone develop into moment, and one you so far. Going out with an experienced a keen nest recorder and sharing the stories which we will no doubt nester will quickly help to show new nesters and adventures of the season with them. always remember the best areas to start looking in, practical As I write this article, the start of the (though I still haven’t demonstrations of techniques and the 2018 season is rapidly approaching and I forgotten about those right sort of gear to use. There is also the genuinely can’t wait! Whinchats!!).

Spring 2018 LIFECYCLE – 17 FIELDWORK | Corn Bunting Corn Bunting fledgling in oats, by Matt York Corn Bunting fledgling in oats, by Matt

Fledglings can be difficult to spot in crops during their first week out of the nest.

Living on the edge

Nest recording is a powerful demographic tool. It provides a direct measure of breeding success which, along with dispersal and survival, help to define population trends. In this article, Rosemary Setchfield, a Conservation Scientist at the RSPB, illustrates how nest record data can reveal important demographic processes that in turn inform conservation management.

So, you are a nest recorder? Maybe you are particularly when pinpointing a nest first the competitive type, trying to find as many time. The key to good triangulation is nests as you can each year? Or maybe you patience and accuracy when making field prefer to concentrate on a favourite species sketches and setting markers. or patch. Have you ever thought about First you require a friendly farmer getting more out of your hard-earned data? who is happy for you to search for nests NEST VISITS Although an extreme example, I would like in his/her fields; always offer to provide Attempting to visit a to show you how a project designed around them a summary report of your findings. nest within the first six nest record data provided important insights Then, you invariably need several early days of nest-building into processes affecting breeding success in mornings watching for evidence of nesting is to be discouraged Corn Buntings, which has helped to inform behaviour. In most years, we find females to ensure at least a an effective conservation solution. OK, rarely lay their first egg before the second partial clutch is present, so we’ve chosen a difficult species, but the week of June. Nest-building is usually a minimising the risk of principles below can be applied to add value week before that, and is often heralded abandonment. If you to projects on any species. by ‘chipping’ calls from the adults and miss nest-building, you intermittent, energetic sequences of song may have to wait more FINDING CORN BUNTING NESTS from the male. than an hour between Corn Bunting nests are reasonably hard Take all the usual precautions when incubation breaks for to find, especially when they occur in visiting nests. Set your marker canes a triangulation line, the middle of cereal crops. The species is carefully along triangulation lines and use although the female remarkably devious, unless you are lucky tramlines to make your way towards the will usually return enough to catch a female nest-building. nest area. The final push into the crop within 20 minutes. Flushing incubating females off nests is not should be conducted with utmost caution. Beware: return to a feasible method of finding nests within We take big, high strides, using bamboo incubation may be crops as they avoid tramlines (tractor canes for balance, to minimise potential delayed or prevented if wheel tracks). You invariably have to resort crop disturbance cues for predators. Use you are within 100 m to triangulation, sometimes over large the canes for parting vegetation, to ensure of the nest site. distances. This is a satisfying skill to master, your next step is nest-free. Take special

18 – LIFECYCLE Spring 2018 Corn Bunting | FIELDWORK

care around fledging, as well-camouflaged INFORMING CONSERVATION SOLUTIONS THANKS chicks crouch in the crop during their first This is the holy grail of conservation This research was week out of the nest. scientists: obtaining results that inform part-funded through an simple and cost-effective solutions for AfBiE (Action for Birds COLLECTING DATA FOR EXTRA VALUE population recovery. Our data showed that in England) partnership We visited nests every three to five days, females selected small crop areas for nesting with Natural England. recording nest data. Through experience, that were especially dense in cereal stems we were able to judge brood age, allowing and, because we also recorded nest distance FIND OUT MORE us to estimate hatching and first-egg dates from the nearest crop edge, we managed to To read more about (the incubation period usually lasts for discover a method for improving breeding the project visit: 12 days, beginning with the penultimate success. Females selected nest sites close to https://ww2.rspb. egg). Nest data alone showed us that early crop edges (15–30 m), where the chance org.uk/community/ nests were more likely to succeed than of nest survival was low, more often than ourwork/b/ later nests, and that warm spring weather expected by chance. No end of head- biodiversity/ was linked to larger clutches and earlier scratching suggested ‘why’ they chose these archive/2016/12/06/ breeding attempts. areas and I finally learnt it pays to ask a research-finds- One way to increase the value of farmer: he told me that seed is overlapped simple-solution- your nest data is to monitor nests within in these areas during crop sowing. Eureka! to-save-our-corn- territories across the whole breeding This fuelled an experiment confirming buntings.aspx season. This can provide important, that double-density seed could attract difficult-to-obtain data on multiple nesting females away from low- brooding attempts. If you are confident survival areas to other parts of the crop. that you are watching the same female, Importantly, our demographic data were record if a second clutch is laid, and follow used to build a population model showing it through until nest completion. So far that, if females were attracted to areas at we have found important patterns in the least 100 m from crop edges using similar probability of females producing a second solutions, enough chicks would fledge to clutch, related to nest habitat quality and allow populations to increase. the date of first-nest completion. Habitat information can also bolster TOWARDS NEST RECORD PROJECTS the value of your nest records. Vegetation If you have the time and enthusiasm, data can reveal what cues females are why not develop a nest recording project seeking for placing their nests. What along these lines? Our results arose from to measure is a tricky one though. We a data set of c. 100 nests in recorded crop height, bare ground each of several years, spread exposure and crop, grass and weed covers across a set of study sites. A before finally finding that total cereal single nest recorder might crop stems in a small area around the manage a single species at nest (25 x 25 cm) was important. This a single site over several information is required from the nest site, years. A consortium of as well as from the surrounding crop area similar-minded individuals for comparison. Of course, you can only could multiply this effort take measurements after the chicks have at other sites and, ‘bingo’, fledged to avoid nest disturbance, and you collect enough data for Setchfield by Rosemary Nest depression in barley, you have to work out how much data you similar types of analysis. need to collect (a friendly statistician is Of course you may need invaluable). And it is not just vegetation to find someone to do the data that are useful. We recorded the number-crunching, but distance between nests and the nearest many researchers or students crop edge, and found that nests closer to would jump at the chance crop edges were more likely to be predated to publish results from good by mammals. Using the exact dates that data sets, and could at least In barley crops, cereal stems are often clutches were laid also showed us that this provide some valuable initial broken around Corn Bunting nests, effect intensified for late-season nests. advice. providing a useful cue.

Spring 2018 LIFECYCLE – 19 RETRAPPING ADULTS FOR SURVIVAL | Tree Sparrows Matt’s RAS site, by Matt Prior

The farming community has also undertaken habitat improvements, including creation of 12 dewponds and the planting of many miles of hedgerows and a huge acreage of conservation cover crops.

Sowing seeds of a Tree Sparrow RAS

In 1999, as Conservation Officer for the Wiltshire Ornithological Society, Matt Prior set up the Wiltshire Tree Sparrow Recovery Project, with assistance from the RSPB. Since then, the project has grown to include over 1,100 nest boxes and 12 major feeding stations across an area of 700 km2. As Matt explains, through years of partnership working, the farming community is now highly engaged with the project, providing seed and, in many cases, filling the feeders.

Well-stocked feeding stations are pivotal strengths of our recovery project is that it to both the species’ recovery and the RAS is undertaken at the landscape scale, and if project. Each consists of large hanging one colony declines, another may be able feeders, seed scattered under hedgerows to prosper. Our retraps have shown how and into conservation crops, or a mixture diminishing colonies have been augmented of all three, depending upon the situation. by nestlings from our boxes that have We ring at these winter feeding sites once dispersed from up to 32 km away. or twice each year to minimise disturbance. The most obvious way to capture adult The recoveries during these sessions tend to Tree Sparrows during the breeding season be of birds ringed as nestlings during the would be by lifting birds off the nest, and previous summer, either from the same site if this were possible, Tree Sparrows would or from other sites up to 12 km away. The be an ideal subject for a RAS project. ringing data produced during these winter Unfortunately, Tree Sparrows are prone ringing sessions have helped us plan where to desertion if lifted off a nest with eggs; to erect new nest boxes and establish more the desertion rate can be as high as 67% feeding stations to expand the project. during early incubation (Kania 1992). Interestingly, during the course of ESTABLISHING A RAS the nesting season I do sometimes touch Having undertaken a fair amount of adults accidentally, especially if they are ringing, we realised that we knew very little nestled down in a deep nest; provided about the age structure or origins of the I withdraw my hand without picking breeding population, which could provide the bird up, I have never experienced a more detailed information about how desertion. The mantle of a Tree Sparrow REFERENCE colonies are formed and sustained. This gives it the perfect in-nest camouflage, Kania, K. (1992) Safety of knowledge is important as Tree Sparrow and I think it is possible that if the adult is catching adult European colonies are known to suddenly disperse or touched, but not handled, it thinks it has birds at the nest. Ringers’ implode; we ourselves have had a colony of managed to hide successfully so it doesn’t opinions. The Ring 14, 5–50. 28 pairs vanish in one year. One of the key desert the nest.

20 – LIFECYCLE Spring 2018 Tree Sparrows | RETRAPPING ADULTS FOR SURVIVAL

The BTO was very keen for us to turn across it; we then catch the birds as they our project into a RAS, having established swarm up and down this hedgerow. The that the sensitivity of Tree Sparrow to average April catch here is 30 Tree Sparrows handling occurred when the bird is in the per session. nest, not near it. The RAS area was selected The second site supports about 300 Tree to be a 250-km2 area of predominantly Sparrows throughout the winter and has a chalk arable farmland within which most of breeding colony of 15 pairs in nest boxes the inter-site movements take place, and the and 10 pairs in natural cavities around a majority of the nest boxes are located. barn, alongside a 1-km hedgerow. This hedgerow has 11 huge feeders situated along CATCHING FREE-FLYING TREE SPARROWS its length, provisioned by the farmer who The most effective ringing sessions have grows his own millet for this purpose. The been in mid April, catching birds at the two barn has a large bramble patch in which the major feeding stations. By this time, most of Tree Sparrows roost at night and also rest in the winter flocks have dispersed and fewer by day. They exit this roost and then sweep of the remaining individuals will move up and down the hedgerow visiting the to other breeding sites, with the possible feeders. We are very lucky that the farmer exception of birds that breed on top of the has allowed us to cut net rides across the hills, which tend to arrive at their breeding hedgerow and the feeders have been sited sites later. First-brood laying dates vary by very near to these. The average April catch five weeks, with many of the earliest sites at this site is 24 Tree Sparrows per session. being about 150 m above sea level and the latest sites being up to 250 m above sea CATCHING AT THE NEST level. We try to focus our breeding-site catching The first site is a huge colony, the main when birds are on their second broods, with wintering flock numbering 350–400 birds, a few sessions in the third-brood period. with 36 pairs using nest boxes, a further The standard approach in the midst of the 30 occupying natural sites and 35 more breeding season is to get to the site at least pairs breeding within 2.5 km. A hedgerow two hours before dawn and, operating of about 150 m in length links the main silently without any light, put nets up in breeding site with a maize silage clamp, front of the boxes, leaving 4–6 m between the prime feeding area. We have sited two the box and the net so as to avoid any large feeders by a gap, halfway along the connection between being caught and the hedgerow, and simply put two 6-m nets nest box. Some birds exit the boxes by flying Nets set between a hedgerow and barn, by Matt Prior

Spring 2018 LIFECYCLE – 21 RETRAPPING ADULTS FOR SURVIVAL | Tree Sparrows

Tree Sparrow Nesting Results 300 2500

250 2000

PIT-tagged Tree Sparrow, by Matt Prior Tree PIT-tagged 200 1500 Number of pairs 150 Number 1000 100 fledged

500 50

0 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

sideways from the box, be successful, but they are even harder to and birds tend to be quite catch for a second time. We were therefore consistent in the route they keen to try a different, passive retrapping take. We notice this as we technique to compare longevities between are going around checking methods. the boxes for nest records For the past two years, we have fitted and ringing, so for certain birds with PIT tags during winter sessions boxes we put the nets at at one colony of 21 nest box pairs situated different angles to intercept the flight lines. in a large rural garden. The landowner then If the site has a feeder, we also put a net up moves two data recorders around the site, by it, or across gaps in hedgerows that are putting them onto boxes when the chicks foraging flight lines. are between four and seven days old. It is vital not to compromise the welfare In 2016, 11 tagged birds used the of the nest box contents and so we plan boxes and in 2017, 14 tagged birds used the session for when the majority of the them, but no birds from the first year were broods are older than four days; all birds still present the following year. We were are processed quickly and the nets in front expecting to find that some birds may use of the feeders are taken down an hour after boxes in successive years so these initial dawn, which then leaves the rest of the results are quite surprising. PIT tagging is day for nest monitoring across the whole not without its pitfalls, however. We have project. These targeted sessions catch, on lost data during downloads and it soon average, eight adults a time, with a bonus became apparent that not enough of the of recapturing lots of juveniles. We have birds are tagged; the only solution is to put been surprised at how fast they disperse, a lot more effort into catching birds prior to with a movement of 2–3 km within three the breeding season. weeks of fledging not unusual. In 2017, 57 In the early years of the project, our only of the adults recorded by the RAS project aim was to conserve Tree Sparrows in our were ringed in our nest boxes and so are of area. With the population ever increasing, known age; of these, 79% were hatched in we are now driven to understand their 2016, 17% in 2015 and 2% in both 2014 population dynamics better and to help and 2013. others with their Tree Sparrow projects. We will therefore be spending many more hours PIT TAGGING trying to catch even more Tree Sparrows Like all sparrows, Tree Sparrows are hard during the breeding season, using a few to catch and net sets have to be cunning to more-imaginative trapping techniques.

22 – LIFECYCLE Spring 2018 Ringing Committee update | COMMUNITY

What RIN do for the other 363 days

I am writing this column a few days after my spring trip to Thetford for the BTO Board and Ringing Committee (RIN) meetings, and while Easter throws rain, snow and an easterly gale at the windows. The Chiffchaff and Sand Martin seen on the coast a few days ago will be having a pretty hard time, tag, BTO fitted Cuckoo with a satellite Peckham the and there’s no incentive to venture outside!

SMTP expertise spans the manufacture, attachment and use of special equipment, as well as avian veterinary experience and knowledge.

These trips and meetings always developments which will require new on the best systems to use before they remind me just how much effort support materials to be provided in the submit their applications. To address and commitment volunteers put future, via the novel routes outlined this matter, we have formed a Tag into the BTO and its activities. The in the paper presented at the latest Attachment Group (TAG), led by Ewan Board members contribute hugely RIN meeting, and the Manual group Weston, whose aims are to collate, to the overall direction of the BTO, will act as a source of advice on these. co-ordinate and provide information and RIN members contribute far The Training group considers the best on the best practice of choosing and more than might be envisaged from ways we can develop ringing training, fitting tags to birds. Already, Ewan has a formal timetable of two committee permits and standards, as we look for provided some advice to two ringers, meetings per year. Most members a new approach to these, and we had who contacted the group concerning are on one or more of the formal or a good discussion on the standards projects on Little Terns and Bali informal subgroups that we have (see required for a pullus endorsement at the Mynas, and the group aims to help any page 24), which involves them in RIN meeting. ringer find the best options for their substantial work between meetings. The Many more ringers provide us with projects. One early proposal is to hold Ringing Standards Select Committee ongoing help, advice and guidance. a workshop that will focus on the best considers and approves new A-permit The Cannon Netting Technical Panel practice and techniques for attaching applications, and deals with any continues to review and advise on this harness-mounted transmitters for disciplinary matters that arise. Richard specialist area, and the Special Methods passerines. They are currently looking Broughton is part of the Editorial Team Technical Panel (SMTP) adjudicates into venues for this workshop, and for LifeCycle, and helps to guide what on permissions for the use of novel hope that it will complement the raptor is published here. Adrian Blackburn, trapping methods and the use of new harness workshop which was held our new elected member (see page technologies in ringing, marking some years ago. They are also open 24), agreed at the spring meeting to and tagging birds (see page 25). We to suggestions for other workshop or help the Bird Observatories Council to welcomed Brian Cresswell, the new forum subjects. adjudicate on awards for the Young Bird Panel chair, to the spring RIN meeting, If you have an interest in or Observatory Volunteers programme. when he outlined his thoughts on the questions about the work of any of The Manual group is advising on future work of the Panel. these groups, do remember that you can the update of the Ringer’s Manual Linked to this, RIN members have email [email protected] and your email will (which is currently being undertaken been aware that whilst the SMTP be forwarded to the appropriate person; by Jacquie Clark and me), and has considers applications to use special they are working hard to help you and already provided new guidance on methods, it has not been simple enough feedback is always welcome. ringing heron and egret pulli. Without for ringers considering using tags and Ian Bainbridge, on behalf of the a doubt there will be more ringing other similar equipment to get advice Ringing Committee

Spring 2018 LIFECYCLE – 23 COMMUNITY | Ringing Committee update

INTRODUCING YOUR NEW RIN MEMBER

ADRIAN BLACKBURN I was born and brought up on an isolated just the course participants seeking training farm in east Lincolnshire and was interested or advancement. in wildlife, in particular birds, from a very During the last 50 or so years, I have early age. Although I have no recollection of been involved in most types of ringing in the event, my mother told me she found me the UK ranging from the usual mist netting inspecting a Woodpigeon’s nest, about 15 to regular visits to Sule Skerry ringing feet up an apple tree, when I was three years seabirds, and monitoring of breeding old. The interest in birds was encouraged owls and raptors in Nottinghamshire and by my primary-school teacher and really Lincolnshire. I trained for a cannon-net took off when I started to visit Gibraltar endorsement in the mid-nineties and Point at the age of 10. It was here that I have been undertaking a long-term study first became involved with ringing; I started of Wigeon in north Nottinghamshire training there in November 1963 under the ever since. I have also had considerable guidance of the warden Barrie Wilkinson. experience of ringing abroad, including I also helped out on several ringing courses visits to Portugal, Mallorca, Senegal, at the same venue run by Bob Spencer, Ken Gambia and Australia. In 2003 I was Williamson and Chris Mead. awarded the Bernard Tucker Medal for In 1969 my career in teaching brought services to ornithological research. me to north Nottinghamshire where I I am still heavily involved with ringing still reside. After my initial experience of and training, although my attendance at training I have always been keen to impart ringing courses is less frequent these days. knowledge and train ringers to a high I am looking forward to representing the standard. Since 1984 I have organised or views and concerns of ringers over the next attended in excess of 50 ringing courses, four years whilst serving on the Ringing mostly in north Nottinghamshire and at Committee, and I will endeavour to Spurn Point Bird Observatory, but also at implement my election pledge to introduce several other venues around the UK. I have greater transparency, openness and always held the view that ringing courses are democracy. beneficial to everybody in attendance, not

Ringing Committee 2018

The Ringing Committee (RIN) supervises the Members hold roles on specific Working Groups (WG) as follows: operation and development of the Ringing Scheme and the Nest Record Scheme. Ian Bainbridge – Chair of RIN, Chair of Training WG, member of Manual WG RIN meets twice a year, in March and Jen Smart – Vice Chair of RIN, member of Tagging WG September. The agenda, non-confidential papers Stu Bearhop and minutes for each meeting are available on the John Black – member of Manual WG ringers-only pages of the website (www.bto.org/ Adrian Blackburn – RIN rep with Young Bird Observatory Volunteers programme ringing-committee). Richard Broughton – member of Programme WG, member of LifeCycle Editorial Board Members are happy to receive correspondence Tony Cross – member of Manual WG at any time throughout the year. Members’ contact Stephen Hunter details are available on the ringers-only pages Ewan Weston – member of Tagging WG, member of Manual WG of the website. Members can also be contacted Kate Clarke – C permit rep, member of Training WG through the RIN email address: [email protected] Ellen Marshall – T permit rep, member of Training WG

24 – LIFECYCLE Spring 2018 Ringing Committee update | COMMUNITY

The Special Methods Technical Panel

BTO is recognised internationally for to the BTO by the Country Agencies The job of this panel is to assess its high standards, and BTO ringers (Natural England, Natural Resources applications from ringers to use so- are justifiably proud of the skills and Wales, Scottish Natural Heritage called ‘Special Methods’; hence the expertise that they develop, both and the Department of Agriculture, name ‘Special Methods Technical in catching and handling birds and Environment and Rural Affairs, Panel’ (SMTP). SMTP mostly collecting robust biometrics and other Northern Ireland). scrutinises applications to attach tags, data. Furthermore, we all care deeply The law on animal research also but Special Methods also include about the birds that are temporarily in applies to some tagging operations. unusual traps or trapping techniques our care during ringing operations. We Compliance with the Animal (Scientific and the taking of some biological owe the same duty of care to birds to Procedures) Act 1986 (as amended) samples. which we attach tags, not only during (ASPA) is regulated by the Animals in The primary criteria used to handling, but after they are released. Science Regulation Unit (ASRU) of the assess applications are based on the We need to be confident that a tag and Home Office. ASRU have delegated to safety of the proposed technique, the its attachment will not unduly affect a the BTO the responsibility for issuing likelihood of the work providing useful bird’s movements, behaviour or survival. licences for tagging and sampling results and the competence of the To reduce the risk of harm to any methods that fall short of the threshold applicant. Where possible (i.e. if the bird, and to ensure that the same high for requiring an ASPA licence; those tagged individuals are likely to be re- standards for ringing and training that cross the lower threshold are still encountered in future) the panel will are also applied to tagging, BTO issued by ASRU. specify a requirement to monitor and controls the fitting of tags by way of As tagging birds is a highly compare tagged with untagged birds. an endorsement to a ringing permit. specialised activity, BTO has assembled Permission to continue using a Special Legally, this enables ringers to undertake a panel of (currently) six individuals Method must be renewed annually, activities otherwise prohibited under with diverse expertise in bird-tagging and a detailed report on activities the Wildlife and Countryside Act 1981 technology, trapping and tagging undertaken will be required each year (as amended), a responsibility delegated methods, and veterinary science. before a renewal is granted.

BRIAN CRESSWELL, CHAIR OF THE SPECIAL METHODS TECHNICAL PANEL There is a pleasing symmetry in hands-on electronics design but am is not the easiest tightrope to walk, with the succession of the SMTP Chair still closely involved in guiding tag the increasing urgency of conservation from Rhys Green to me. Rhys first development. Tracking technology has research, complex, rapidly changing introduced me to radio-tagging when become extremely sophisticated in the technology and the necessity to protect I worked for him 33 years ago. After past few years, with wildlife telemetry individual birds and abide by animal- finishing a biology degree it was my first companies and university departments welfare legislation. Rhys will be a tough ‘relevant’ job; researching Snipe and building myriad devices to monitor act to follow as Chair, but I’ll do my Black-tailed Godwits on the Somerset birds’ movements and behaviour. These best to stay on that tightrope. Levels and Cambridgeshire Fens. In are exciting times in bird tracking. 1985, Rhys recommended me for a job I have always maintained an interest at Biotrack, a company making wildlife in field research, which is what I really tracking equipment, where I’ve been wanted to do after graduating. My ever since. main interest is in Nightjars, which I’ve Back then, I was Biotrack’s only ringed and tracked with friends in Stour employee. Now, 32 years and c. Ringing Group since joining in 1985. I 200,000 tags later, we employ 35 have quite a lot of field experience too, people and have supplied tracking having tagged 26 bird species (and a equipment for over 1,000 species few mammals and fish) either through in 130 countries. I started out my own projects or helping others. My building radio tags, but soon I was favourite projects were on Barn Owls also answering letters (not even faxes and Bearded Tits in the UK, Red-billed in those days, let alone email!) from Curassows in Brazil and American biologists wanting tracking equipment. Woodcock in Louisiana. Later I taught myself electronics and I feel honoured to return to the started designing new radio tags. Now, SMTP as Chair, having been a member as Managing Director, I no longer do of the panel once before until 2015. It

Spring 2018 LIFECYCLE – 25 FIELDWORK | Ecosystem approach to nest boxes European Hornet queen, by Richard Broughton European Hornet queen, by Richard

Although they look fearsome, the large and impressive European Hornet queens are usually quite docile when scouting for nest sites in early spring, when they may appear inside nest boxes. If left undisturbed they may build their paper nests suspended from the box roof.

What’s in the box?

There are an estimated 4.7 million nest boxes in UK gardens (Davies et al. 2009), with many thousands more in parks, woods and nature reserves, representing a vast resource for wildlife and potential nest recorders. The majority of these will be small-holed boxes, aimed largely at tits, and usually made of wood or woodcrete. As Richard Broughton, an Ecologist at the Centre for Ecology and Hydrology explains, it is not just birds that make use of this fantastic resource.

Monitoring of small nest boxes contributes climate change, or to fill in gaps for species around 17,000 nest records per year, which where the current range is poorly known. is about a third of the NRS total. Just under half of these annual nest box records are BUMBLEBEES Blue Tit nests, and another third are Great Bumblebees are increasingly common in Tits, with the remainder dominated by nest boxes meant for birds, and in early TREE BUMBLEBEES Tree Sparrows, Pied Flycatchers, House spring one may lift the lid of a box to find In an era of declining Sparrows, Common Redstarts, Coal Tits a large queen bumblebee resting inside. pollinators, the Tree and Nuthatches, with a smattering of Marsh These early bees are often Buff-tailed Bumblebee, with Tits, Wrens and Willow Tits. Bumblebees (Bombus terrestris), an abundant its distinctive ginger As any nest recorder can testify, however, and widespread species that is expanding thorax, black abdomen birds are not the only occupants of nest northwards into the Scottish Highlands. and white tail, is a boxes. All manner of invertebrates and Queens emerge from February to search for phenomenal success small mammals can be found, including nest sites in old vole or mouse nests, but will story. Having expanded parasites; some are competitors for the also investigate nest boxes and rest inside on across mainland nest box, others just looking for temporary cool days. When disturbed they’ll buzz as a Europe, before arriving shelter. Although some of these potential warning and perhaps fly off clumsily. at Southampton in inhabitants are undesirable from an avian The most frequent ‘nest box bee’ is 2001, they have spread point of view, many are fascinating in their a relative newcomer, however: the Tree rapidly across England own right and some are of great scientific Bumblebee (Bombus hypnorum). This is and Wales, reaching and conservation interest. a species of woodland, parks and leafy Scotland in 2013 and Small mammals and many insect gardens, which habitually nests in tree Ireland in 2014. They groups tend to be greatly under-recorded, cavities (as the name suggests). are still spreading and and so nest recorders are in a position Tree Bumblebees have a particular liking infilling, so records are to contribute useful data to the relevant for nest boxes and are direct competitors important in mapping recording schemes. Such records can have with nesting birds; one with a sting in the their expansion and real scientific value, helping to map the tail! In my Cambridgeshire nest box studies, abundance. expanding ranges of species responding to Tree Bumblebees were able to displace Blue

26 – LIFECYCLE Spring 2018 Ecosystem approach to nest boxes | FIELDWORK

Tits from active nests and take over the box (Broughton et al. 2015). Queens emerge to search for suitable nest cavities just when tits are building or laying, and a tit nest in a dry nest box is just what she’s looking for. The queen will burrow into the nest and buzz aggressively to force the birds to abandon. She will then churn up the material into a dome, burying any bird eggs, and bring in pollen to form into a lump inside on which to lay her own eggs and start a colony. male, by Nadine Mitschunas Bombus hypnorum male, by Nadine Bumblebee Tree A nest recorder gently touching the nest material to feel for cold eggs on a routine check may then hear the queen’s aggressive buzzing from within, which is usually sufficient warning to back off. Tree Bumblebees are very defensive, and once the The Tree Bumblebee is an increasingly common occupant of nest boxes, where it colony is established the workers will guard can take over the nests of tits and other passerines to start its own colony. the nest box entrance, being likely to sting if they are disturbed and may even chase you away for some distance. It is therefore their paper nests in boxes that remained always advisable to check suspect boxes unoccupied by birds (Broughton et al. from a distance and look for bees around 2015). Saxon Wasps are quite common the entrance, especially if a queen was heard in nest boxes on the Continent, and with buzzing on an earlier visit. Other bumblebee climate change and range expansion they species may also take over bird nests in a can be expected to occur more often in REFERENCES similar way, and all are worth recording as British nest box studies. Broughton, R.K. et al. this mostly seems to occur in nest boxes, Nest recorders can help map the spread (2015) Nest-site competition being very rare in natural cavities. of Saxon Wasps through Britain, and between bumblebees possibly into Ireland, although separation (Bombidae), social wasps OTHER INSECTS from other small wasps can be tricky. Tree (Vespidae) and cavity- Other feisty insects likely to occur in nest Wasps (D. sylvestris) and Median Wasps nesting birds in Britain and boxes are various wasps, the most impressive (D. media) can also occur in boxes, as can the Western Palearctic. Bird being the European Hornet (Vespa crabro). Common Wasps (Vespula vulgaris), and Study 62, 427–437. Hornets are also expanding their range from taking photos or specimens for checking by Davies, Z.G. et al. (2009) central and southern England and records experts is recommended. By autumn a wasp A national scale inventory are valuable from all areas. Hornet queens colony will have died off and there are often of resource provision will investigate nest boxes and may begin a dead specimens under the disintegrating for biodiversity within colony by building a paper nest suspended nest within the box. domestic gardens. Biological from the roof, possibly evicting any Conservation 142, 761–771. resident birds. Hornets are not abundant SMALL MAMMALS Hebda, G. et al. (2017) and their conservation status is unclear, so Several small mammals will habitually use Decomposition of nest nest boxes can be useful sources of local nest boxes, particularly Wood Mice. Like material in tree holes and breeding records. Although generally docile, bumblebees, Wood Mice will reorganise the nest-boxes occupied by Hornets may attack if the nest is disturbed. nest material into a ball, often bringing in European Starlings Sturnus The stings are very painful, and if a box is other material such as leaves. Female Wood vulgaris: an experimental opened by mistake the best option is to run! Mice will sleep communally in nest boxes, study. Acta Ornithologica Another wasp to be found in nest boxes and four or five may jump out if disturbed, 52, 119–125. is the small Saxon Wasp (Dolichovespula but single females may also breed inside Maziarz, M. et al. (2017) saxonica), which colonised Britain in 1987 during spring or summer. Microclimate in tree cavities and has since become locally common, Wood Mice are quite arboreal, and can and nest-boxes: Implications but is still expanding its range. This species be found in nest boxes several metres above for hole-nesting birds. Forest seems to like nest boxes too, but in the the ground in woodland and farmland Ecology and Management Cambridgeshire study they only built hedgerows. Overwintering Wood Mice may 389, 306–313.

Spring 2018 LIFECYCLE – 27 FIELDWORK | Ecosystem approach to nest boxes

fill nest boxes with seeds or requires that they remain undisturbed. acorns as food larders; as Brown Long-eared Bats seem partial to many mice don’t survive to Schwegler nest boxes, roosting at the apex of return to their stash, these the roof, but other species are also potential need to be removed before inhabitants. Contacting the local bat group spring if birds are preferred. is advised for help with identification and In Cambridgeshire woods, recording.

Brown Long-eared Bat, by Richard Broughton Bat, by Richard Brown Long-eared up to a quarter of nest boxes checked in March had FLEAS hosted overwintering Wood Finally, it’s worth mentioning a genuine Mice, with evidence of nests problem species associated with nest boxes: or food stores. the Hen Flea (Ceratophyllus gallinae). Many Another fantastic nest recorders will be familiar with seeing mammal that seems to like a horde of fleas surrounding a nest box nest boxes is the Pygmy entrance, waiting to jump onto anything Shrew, which is often found warm-blooded, be it avian or human. Such in boxes fixed at 1–2 m infestations are virtually unknown in natural above the ground, intended tree cavities, and reflect the distinctive for Marsh Tits in my study microhabitat created by nest boxes. A Brown Long-eared Bat roosting in a nest box, woods. Pygmy Shrews also Compared to tree cavities used by small with the long outer lobes of its ears tucked reshape tit nest material birds, which are typically found in living under the wings. into a ball, but can be trees, nest boxes have thinner walls and so distinguished from Wood Mouse activity offer less insulation, but also a much drier by the presence of a characteristic latrine microclimate (Maziarz et al. 2017). This of black droppings in one corner of the is important, as the humidity in natural box. Gently probing the nest often reveals cavities allows nest material to effectively the occupant. Records of species such ‘compost’ over the winter, making tree as Pygmy Shrew, Yellow-necked Mouse, cavities almost self-cleaning and ready for Hazel Dormouse and Edible Dormouse are birds to use again the following spring. particularly valuable to recording schemes, Nest material decomposes at a and the widespread Common Shrew and much slower rate in nest boxes, and Bank Vole may also occur. the microclimate can be so dry that old nests can ‘mummify’. A study of BATS Starling nests found that 98% of plant Bats may sometimes be found roosting material in nest boxes remained intact in nest boxes, and their special protection over winter, compared to only 25% in tree cavities (Hebda et al. 2017). This old material in nest boxes provides habitat for overwintering fleas which then infest broods Where to submit records of other species found in nest boxes in the following year, at levels way beyond that seen in tree cavities. Hornets, wasps and bumblebees: www.bwars.com is an excellent resource for identification and submitting records. CLEANING NEST BOXES Small mammals: www.alerc.org.uk is the network of local Environmental Cleaning out old nest material soon after Records Centres fledging reduces the flea problem, but also Bats: All bats are specially protected and should not be disturbed when removes habitat for overwintering mammals roosting. Advice and contact with local bat groups is available from the Bat and other invertebrates. As a compromise, Conservation Trust at www.bats.org.uk I clean out boxes when the fleas are largely www.brc.ac.uk/irecord is an app and website for submitting and sharing dormant in the old nest, giving other species records of any species to be checked by experts and collated into the a chance to have overwintered. And if I find appropriate national recording system. a bumblebee, Hornet or small mammal www.ispotnature.org is a friendly online community where you can ask for inside then I leave them in peace and make help with identification from photos. a note of it to submit a record.

28 – LIFECYCLE Spring 2018 Safety of ringing | PUBLICATIONS

A better understanding of risk

Any effect of capturing wild birds on their individual welfare, or that of their wider populations, is an important ethical consideration. It also has significant implications for the integrity of the data collected, as Barber Siskin in a mist net, by Lee biases may be introduced if capture and handling bring about changes in behaviour or survival. Ultimately, the benefit of the information accrued when capturing wild animals for study needs to outweigh the potential risk to individuals that are caught. New BTO research, just published, aims to quantify these risks and help us to reduce them.

The study aimed to identify how to make ringing birds as safe as possible.

Wild birds have been marked with mentored and then formally appraised incidence of predation – the single metal rings as part of scientific before they are able to operate largest identified cause of mortality, studies throughout the world for unaccompanied, a process that typically accounting for over 70% of deaths over a century. The data generated by takes several years and involves handling – was seasonal, with risk increasing these studies have provided much- a significant number of birds. during the winter. Mortality rates, needed information on movements, Despite this, there are occasional although very low, varied between demographic processes and individual incidents of capture-related mortality species; the apparent risk was greatest life histories, as well as helping to guide or injury. Defining any threshold of for Bullfinch and Chiffchaff. A similar conservation actions. Understanding ‘acceptable’ mortality in the context of study in North America reported a the welfare implications of such studies research into wild bird populations is slightly higher estimate (0.23%) than is an important part of determining the a difficult and sensitive issue, but it is that found here. Whilst it is important balance between the knowledge gained important that we understand the level to understand and to minimise the from such studies and the potential risk of risk, and its implications for welfare scale of any effects on capture-related to the individuals that are caught. and data quality. mortality or injury, it is unlikely that a The potential effects of fitting rings The study quantified the reported zero mortality rate will ever be possible and electronic devices to birds have mortality rate among common when trapping and handling wild been investigated through a series of passerines recaptured using mist- animals for scientific purposes. reviews and studies. The direct effects nets, from data submitted to the The study also makes a number of of the capture methods themselves, BTO. Factors which may influence recommendations; some of these will though, have received less attention, the likelihood of mortality were also help to refine our guidelines for those with few published studies quantifying investigated, facilitating production of trapping and handling wild birds, while the risks. A new study addresses this improved guidance for those operating others suggest additional opportunities gap by examining 1.5 million recapture mist-nets to capture wild birds. Overall to secure information that could be records of 166 passerine species, mortality rates were low – the average used to better understand risk factors caught using mist-nets operating was 0.11% – with most fatalities and associated mortality. under the British and Irish Ringing reported to have occurred before Scheme. Mist-netting is considered to individuals had been extracted from be safe and effective when carried out the nets, and some may have occurred REFERENCE by experienced, trained individuals, for reasons unconnected with ringing, Clewley, G.D. et al. (2018) Estimating mortality following published guidelines. The e.g. the individual was already in poor rates among passerines caught for ringing with training process is both structured and condition. Juvenile birds appeared to mist-nets using data from previously ringed birds. intensive, with volunteers individually be at greater risk than adults, and the Ecology & Evolution doi:10.1002/ece3.4032

Spring 2018 LIFECYCLE – 29 TECHNOLOGY | DemOn

The ‘Refine Location’ tool allows you to map precise nest locations within an existing ‘General Site’, either by specifying a point on a map or a 10-figure grid reference.

DemOnic nesting

There is no doubt that IPMR played a pivotal role in setting the Nest Record Scheme back on track but, as Mark Cubitt would acknowledge, basing the NRS functionality on the ringing system necessitated some compromise. DemOn gave us the opportunity to tackle some of the issues that arose from this; Dave Leech reports on how we’ve taken it.

Many of the new recruits to the influence the changes in populations saved time by allowing details to be demographic schemes must wonder if sizes monitored by census surveys such defaulted when the site was selected, there was ever a time when DemOn as the BTO/JNCC/RSPB Breeding but also ensured that locations were wasn’t being built. It has been an epic Bird Survey. Over the last decade we’ve consistently identified when re-used journey and it is by no means over been trying to reflect this by increasingly in subsequent years. While this was yet, but with a quarter of a million integrating the two schemes; IPMR very helpful for predictable species, it ringing encounters input into the represented a big step forward in this was less suited to open nesters such system so far exceeding the volume of respect and DemOn takes us still as, to pick a species at random, Reed submissions now received via IPMR further. As in IPMR, adult and pullus Warblers, where the nest would not over the same period, the ringing side ringing data can be entered through the occur in exactly the same place two of the functionality is becoming well- NRS side of DemOn but this process years running. The default habitat established. Development of the nest now works both ways, with nestling values relating to the IPMR ‘Place’ from recording element started much later encounter records entered through the which the record originated would in the process and December 2017 was ringing side of the system automatically still be relevant, but the grid reference the first sight that many of you had generating a single-visit nest record to would need to be edited every time to of it, but there have already been over which subsequent visits can be added provide a precise spatial reference. 8,000 records entered and the feedback via the NRS functionality. As any ringer One of the core concepts of received thus far has been invaluable, so has the potential to create a nest record DemOn is the ability to create very thanks to the 300 nest recorders who in this way, anyone registering for their precise locations while you are actually have taken the plunge so far. T permit will now automatically be inputting the nest record, rather than registered as a nest recorder. having to set them up in advance. This BRINGING IT ALL TOGETHER can be achieved in two ways: As I’ve written many times over the ACCOMMODATING NOMADIC NESTERS • The ‘Add New Location’ button years, the NRS and the Ringing One of the things IPMR did very well allows a nest site at a new location Scheme are really two halves of the was enable details of regular breeding to be specified, either by typing in same whole, providing complementary sites, be they artificial boxes and a grid reference (up to 10 figures, information on the degree to which platforms or natural ledges and crevices, equivalent to the nearest metre, so changes in breeding success and survival to be specified in advance. This not only a big advance in accuracy relative

30 – LIFECYCLE Spring 2018 DemOn | TECHNOLOGY

to the IPMR 6-figure maximum) move nets between a large numbers of is now possible, again alongside fields or clicking on a map. different locations within and between allowing you to record the evidence • The ‘Refine’ button allows a more seasons, will testify. Again, it is possible supporting your estimate. Note that accurate location to be specified to associate captures with very specific this is not a variable that BTO will within a pre-existing ‘General locations without clogging up your incorporate in our annual estimates, site’ (equivalent to over-writing drop-down lists of sites using the ‘New’ as different recorders may use it in the 4-figure grid reference and ‘Refine’ options as above. different ways, but we hope it will be corresponding to the selected useful for your own summaries and ‘Place’ in an IPMR nest record NESTING CSI analyses. Another handy new feature is with a 6-figure grid reference, only While there would clearly be no the ability to record the precise location again to greater accuracy). point in monitoring nests if they all of fledglings sighted away from the nest. For my Reed Warbler nests, I use succeeded, there’s no denying that the latter option, so my ‘General Site’ failures, especially late in the nesting WORK IN PROGRESS at Cranwich acts as an umbrella for cycle, can cause the blood to boil, So that’s the good news; those of hundreds of point locations that relate driving even the most independent you who frequent the DemOn to individual nests, each with its own scientific minds to pointlessly curse User Support Community page on 10-figure grid reference derived in corvids, mustelids, rain or gales. Facebook will doubtless be aware that the field using a GPS. Obviously, I One thing that always frustrated me, there is still work to be done, with the don’t want to see all these in a drop- however, was the lack of capacity to linking between nest records and pulli down menu of locations that DemOn record the evidence allowing you to pin ringed on someone else’s rings causing presents me with in future, as the the blame on the appropriate culprit. particular issues. We appreciate these list would be endless and I’m very I need worry no more; by clicking on bugs are annoying, and we’re working unlikely to ever record another nest the relevant failure code in DemOn, on them as fast as resources allow but, as in exactly the same location. For this you can unlock additional fields that someone who has now entered 400 nest reason, new or refined locations are not allow you to record more information records with pullus encounters into the ‘remembered’ by the system (i.e. not about the putative cause of death or system, I can assure you that DemOn is presented to you as an option in future) disappearance and the evidence that led already a viable alternative to IPMR for unless you specifically ask them to be by you to that conclusion. ringers and nest recorders alike. checking a ‘Remember Location’ box Thankfully, many nests do survive when you create them. and a different suite of fields can be FUNDING Note that all of this functionality is unlocked by clicking on the relevant DemOn development is only possible potentially relevant to ringing activities success codes. Many volunteers have thanks to funding from JNCC, SNH, too, as any RAS participants who asked for the ability to record the BTO, the Garfield Weston Foundation target birds at their nests, and therefore number of individuals fledged and that and volunteer contributions.

New functionality allows you to record additional detail about the causes of nest failure by clicking on the failure code.

Spring 2018 LIFECYCLE – 31 FIELDWORK | House Sparrow boxes Male House Sparrow with nesting material, by Denise Wawman Sparrow with nesting material, by Denise House Male

House Sparrows can’t resist feathers from Silkie chickens and will collect them at any time of year, especially in cold weather, when they have young chicks and use them like a duvet.

Are terraces a House Sparrow des res?

This question crops up frequently in the NRS Forum in various forms, and is one which Denise Wawman has spent the last 12 years trying to answer. In this article, she discusses the nest box preferences of the House Sparrows in her garden on the West Somerset edge of Exmoor, where she rings 100–200 individuals a year for her RAS, now in its eleventh season.

In my garden, House Sparrows have a clear of the compartments, on one occasion preference for a south-facing site and most laying eggs in two of them simultaneously. of them nest under the eaves. The most- House Sparrows raised a single brood in favoured nest style is a messy pile of grass, one of terraces in 2007, a brood in either with a partial dome, on the shelf which end of the west-facing terrace in 2016 and forms the top of an artificial House Martin occasionally put a few bits of nest material nest box. These are impossible to monitor inside before moving elsewhere. There was safely as they are situated close together, more success with the standard boxes, all with adjacent nests at very different stages. on the less-favoured northern aspect of the BOX LOCATION House Sparrow pulli are liable to explode house, with seven broods raised. The Swift If you are a light and it can be difficult to keep control of box and the boxes in the garden were never sleeper, or don’t need chicks in what is essentially an open nest, so used. a regular 4:30 am I was very keen to encourage them to move wake-up call, it might to more accessible housing. OUT WITH THE OLD be best to avoid In late 2016, I decided on a complete putting boxes under NEST BOX DESIGN change of plan, partly triggered by difficulty your bedroom window; My campaign to find the ideal House in finding anyone to foot a ladder on the amorous House Sparrow nest box began with a mixture of few days when pulli needed ringing. All the Sparrows are rather standard 32-mm-hole boxes, a couple of boxes on the house were re-sited just under loud! commercially produced terraces and a Swift opening windows so that they could be box, positioned on the walls of the house reached safely, without having to lean out about 3 m above the ground. I had also too far or use a ladder; this raised the height erected some 32-mm-hole boxes, located at of most to about 4 m. The standard boxes about 1.5–2 m high on the workshop and were arranged in pairs. garden fences. I also modified both terraces while Over the years, the terraces attracted repairing them when they started to come the odd pair of Blue Tits, which seemed apart at the joints. I blocked up the front to get confused and start nesting in all hole, leaving just the two side entrances,

32 – LIFECYCLE Spring 2018 and ringingthepulliwasreally easy. ofthehouse.Checkingboxesthe north late brood inoneofthestandard boxes on and abandonedthesite.Therea wasalso chicks duringaweekend oftorrential rain box. Unfortunately, thispairlosttheir both sidesbefore layinginthesouth-facing builtanestin contained apairthatpartially Theother from thesouth-facingpart. andfledgedthree compartments broods window hadapairthatmadenestsinboth had nests!Theoneundermybedroom poorbreeding season,bothterraces very to holesinbrickwork where theyoftennest. an entrancetunnel;more liketheentrance the box,inchesfrom afew theholetocreate boxes Ialsoplacedablockofwoodinside small forHouse Sparrows anyway. In some divider. Theboxes hadalwaysseemedtoo the box, replacing themwithasinglecentral and removed thetwoexistingdividersin Spring 2018 102; Moor Piece Nature Reserve Nestbox Scheme 102; Nidderdale Birdwatchers 100. RingingGroup106;Norfolk Chris duFeu 105; West Midland Bird ClubBoddenham105; Carstramon Wood 103; Lowe Garth 103; Richard Winship Group 111; CoquetIsland RSPBReserve 111; IainInglis108; 108;John Roberts Treswell Wood IPMGroup107; 106; Spurn Bird North Observatory Craig 115; 115; Calf of ManBird Observatory Keith Seaton 114; Southern EnglandKite Group112; CwmClydach RSPBReserve 111; Ringing Dartford Lyndon 119; &Norma Jeffery George Candelin119; 118; Pitt Gary 117;Stephen Hewitt Jeremy Gates117; Steph Tyler Burge &Felicity 116;Ringing Group126; Alexander Christine Flint125; John Griffin 122; Anne Goodall 122; DanielEva 120; BucksOwl&Raptor Group 120; JimRushforth 120; Group 136; Hughes135; Martin Dave Hazard 135; LewisJerry 133; Barker Garry 132; Doug Simpson 132; Jan Pritchard 130; Tony Davis128; Nunnery 143; RockinghamForest RingingGroup143; Mike Russell140; Paul Slater 138; Wicken Fen Group138; Hubble & Tracey 137; Isle of Wight Ringing 157; BarnOwlProject156; Community Suffolk Peter Johnson 151; RobinHusbands151; Simon Dudhill150; Swaledale RingingGroup148; RayGribble Williams & Thomas 163; AllanDawes162; Jack Daw159; Jim Hodson&M158; Waveney RingingGroup157; Berkshire DownsRinging Group WiltshireNorth RingingGroup175; Caudwell172; Barry Keates &Preston169; Leigh & Tony Kelly 168; AllanHale 165; Pitsford Reservoir 164; Short, Bill Haines185; Pearce Geoff 184; Peter Rose 184; HughInsley182; Derek Spooner 179; South Nottinghamshire RingingGroup178; PaulFenwick 176; 195; Kevin Sayer 194; Ted Cowley193; RSPBGeltsdale nature reserve 193; West CornwallRingingGroup188; AndyLeach 186; Denise Wawman 186; Chew Valley Ringing Station 219; BristolNaturalists’ 209;ManxRinging Group199;Society MidLincolnshire RingingGroup195; Bob&Rob Swann & Bateman228; RingingGroup224;West Norfolk North 221;John LawtonRoberts Simon Cox221; Huddleston& 219;Jackson RingingPartnership Greening235;Ringing Group248; Mervyn Simon Taylor 231; Frank Mawby231; RingingGroup 230; Batty Stanford RingingGroup230;Northumbria Lewis 254;NagsheadRSPBReserve 251; Dave Coker 250;Lancaster &DistrictBirdwatching 250;Newbury Society Lawton 301; John Lloyd288; Myers266; ColinGibson284; DavidOliver Geoff 266; Ronald Turkington 254;Nigel 345; Watts John Hyde 332; David Warden 321; Gwent Wildlife Trust 315; Peter Roe 309; Jonathan Groom307; Neil Carter 381; Cook 368;Fledgemore Henry NestRecording Group365; Shropshire RingingGroup356; Nicholas 438; Louch & Thompson 435; South Manchester RingingGroup416; Kevin Briggs416; John Bell412; Stephen Sorby Breck RingingGroup513; Rye MeadsRingingGroup 466;BirklandsRingingGroup439; Jonathan Lingard Devon NestingCrew544; Thetford Forest RingingGroup527; PaulRoughley537; EastDalesRingingGroup516; & Julie Fenwick 706; Tom Dewdney629; West Wiltshire RingingGroup586;Bowden,Ball& Sheppard 551; South Catrina Young 887; EastKent Wildlife Group838;Merseyside RingingGroup822; Arden RingingGroup739; Noel NRS participantswhomonitored100 or moreactivenesting attemptsin2017 In 2017,despite2016havingbeena access formonitoring. under windows for ease of 4–5 mabove theground, and boxes onasouth-facingwall, I wouldrecommend siting commercial terraces.Instead, advise againststandard have learntsofarIwould different stages. risk ofhavingtwobroods at boxes becausethere isno will probably sticktosingle various entrancecorridors.I of 32-mm-holeboxes with it totestvarious otherstyles window withnoboxes under having asouth-facing replace bothterracesand advantage ofneedingto This year, Iplantotake LOOKING FORWARD On the basis of what I On thebasisofwhatI wood justbeyondtheentrancehole. Modified terrace, showingtheblockof House Sparrow boxes |FIELDWORK LIFECYCLE –33

Linnet nest, by Mike Toms

Modified terrace with nests, by Denise Wawman .

SKILLS | Moult

‘Aberrant’ moult: emerging trend?

Last spring’s LifeCycle (Issue 5) included a photo of a Greenfinch that had moulted primary feathers during its post-juvenile moult. As Stephen Menzie explains, such a bird raises a number of questions: does this arise via a developmental accident or is there purpose in moulting this way? And if the latter, in future will we see a population- level shift towards a more extensive moult which may affect the criteria we routinely use to age that species?

Occasionally, we catch birds that really GREENFINCHES don’t fit the expected pattern of post- PJM in Greenfinches is hugely variable, juvenile moult (PJM) for the species in from birds that moult nothing more on question – and by moult, I’m talking about the wing than the lesser and a few median the purposeful symmetrical replacement of coverts all the way through to birds that feathers, not an individual that has lost a have moulted six or seven primaries, two or handful of secondaries to a bramble bush. three primary coverts, and inner and outer Some really do seem like aberrant one-offs: secondaries (see photos below). Primaries a Blue Tit that has moulted primary coverts; are moulted from P5 or P6 and radiate a Whinchat that has moulted primaries outwards in both directions; for example, and secondaries but not tail or tertials; a moult might progress as follows: P5, P4 Tree Pipit that has moulted the eighth & P6, P3 & P7, P2 & P8, P1 & P9. The greater coverts on both wings but had left primary coverts are not moulted with the all median coverts and a few lesser coverts corresponding primaries, though – indeed, unmoulted. These are just a few examples I have never seen a Greenfinch with fewer that spring to mind from my personal than four moulted primaries that has experience. replaced any primary coverts. Instead, Other unusual moults appear to be once the bird’s primary moult has reached simply the extremes of a ‘normal’ post- a certain point it then starts moulting juvenile strategy – Blackbirds that have its primary coverts in a similar radiating moulted tertials and the inner secondary; pattern to the primaries. There is still a REFERENCE Goldcrests that have moulted the central tail lot to learn about this type of eccentric Kiat, Y. & Izhaki, I. (2017) feathers; and, although it might not seem moult; Kiat & Izhaki (2017) found, for Journal of Avian Biology 48, obvious at first glance, Greenfinches that example, that unmoulted primary coverts 380–386. have moulted their central primaries. corresponded with a rapid primary moult. Photos by Stephen Menzie Photos by

Extremes of Greenfinch moult. The left-hand bird has undergone a very restricted moult. No greater coverts are moulted, and three old median coverts have been retained during the PJM (October, Sweden). In contrast, the right-hand bird has moulted all median coverts, greater coverts, tertials, P3–9, S1 & S3–6 and PC4–6 (October, Cheshire).

34 – LIFECYCLE Spring 2018 .

Moult | SKILLS

during irruptions) and Siskins can also moult primaries during their PJM, although seemingly much less frequently. Away from finches, Reed Bunting occasionally Photo by Stephen Menzie Photo by shows eccentrically moulted primaries and I’ve encountered singletons of Blackbird, Blue Tit and Dunnock that appear to have moulted a central primary or two as part of their PJM. It is unclear if extensive PJMs in some species will become a more widespread strategy in the future. The number of extensively moulting individuals seems to be increasing, but is this a genuine trend or are we just getting better at noticing and recording the moult? Climate change may well be playing a part, either indirectly with temperature acting as a cue or directly by influencing resource availability; it is notable that PJM within a species is generally more extensive in warmer climes, e.g. in Iberia, where presence of moulted primaries in the This Reed Bunting had symmetrically moulted above-mentioned species is often the norm. P6–8 and S6 (September, Sweden). Only time – and continued observation of moult – will tell.

Just how extensive can this moult get? Well, that is a slightly theoretical question, as an unringed first-year bird that has replaced all primaries might well be overlooked and recorded as an adult. Ringing nestlings and catching Photo by Stephen Menzie Photo by juveniles immediately post-fledging could play an important role in assessing this by providing known-age retraps. The available data suggest that the majority of juvenile Greenfinches that undergo PJM moult only a few primaries, therefore it is probably unlikely that young Greenfinches undergoing a complete PJM are being missed. If you do catch a bird that you’re not sure about, the inner and outer primary coverts and the central secondaries will be the most commonly retained feathers or the last to be moulted.

OTHER SPECIES Eccentric moult isn’t limited to This Blue Tit had symmetrically moulted all secondaries, P1–8, and the inner Greenfinches. Ringers in Britain & Ireland primary coverts. Unexpectedly, for a bird with such extensive moult, only the are just as likely to come across Goldfinches central tail feathers had been moulted. This is one of only two individuals that have replaced flight feathers during detected with any primary coverts moulted, out of a sample of c.18,000 birds PJM. Crossbills, too, regularly have a – the other individual had symmetrically moulted five primary coverts but no more extensive PJM (complicated further primaries or secondaries. Both are undoubtedly aberrant individuals showing by their unhelpful habit of suspending it unexpected moult patterns.

Spring 2018 LIFECYCLE – 35 CONSTANT EFFORT SITES | EuroCES Fenékpuszt CES site at Lake Balaton, Hungary, by Katalin Odett Balaton, Hungary, Lukács at Lake site CES Fenékpuszt

Ringers operate CES across Europe. This one, on the shores of Lake Balaton, Hungary, catches good numbers of Bearded Tits and Tree Sparrows.

CES Ringing – the European way

When you are noting down the details of the first retrapped Blue Tit of your CES session at 5 am, you are probably thinking more about a nice cup of coffee than global patterns of environmental change. As Rob Robinson explains, however, each capture of a bird on your CES site is now contributing to a growing Europe-wide database that will help us address some of these pressing conservation issues.

The idea behind CES is a simple one. By to find food, or to avoid cold weather. In catching birds one can get some idea of an attempt to balance these differences their abundance; in years when birds are CES aims for one catch once every 10 commoner they will be caught in greater days or so through the breeding season. numbers. However, just going out and By formalising this schedule, we don’t, for catching some birds doesn’t help all that example, catch more young birds in one much since we don’t catch every bird, so we year because we made more visits later in don’t know how our catch relates to what the season, or more adults, if we made more is actually present; and, of course, the more early visits. effort we put in, the more birds we catch. HABITATS At least most of the time! So some ringers EUROPEAN ENTRY Across Europe, CE sites came up with the idea of trying to make Sites were first operated in Britain using are mostly operated their effort more comparable and repeatable ‘constant effort’ in the late 1970s, but a few in similar habitats resulting in a Constant Effort Scheme, years trialling different set-ups and ideas to Britain & Ireland, initially led by Mike Boddy. By making the meant the programme was not formally with about a third of same amount of effort, changes in catches adopted until 1986 (though enough sites sites broadly being between years should tell us what numbers were able to provide data to enable trends characterised as ‘wet are doing; are they going up or down? to be calculated back to 1983). Like most scrub’ and another other simple ideas, it was quick to catch quarter ‘reedbed’. In TIMING IS EVERYTHING on. Finland (1987) and France (1989) were Britain, we have more But when to catch? In the summer, birds among the first to pick up the challenge, sites in dry/thorn scrub breed at different times, so young Long- and now there are 18 schemes operating than other countries, tailed Tits can be caught in early May, but across Europe, from Portugal to Hungary; whereas other CE young Bullfinches rarely before July, and, Croatia and Switzerland are among the schemes also operate for most species the number of breeding most recent countries to join in. a small number of sites adults caught is highest at the start of the In fairness, we need to note that, like in farmland and garden breeding season. In the winter, things are many good ideas, that of standardising habitats. more complicated still as birds move around capture effort was not exactly new. In

36 – LIFECYCLE Spring 2018 EuroCES | CONSTANT EFFORT SITES

central Europe, three sites (Mettnau in southern Germany, Reit in the north and Illmitz in Austria) started a co-operation in 1972 with the same effort expended at each of the three sites – and what effort! They used 52 nets (albeit each one was only seven metres long) in eight habitats daily through the autumn migration period (July to October). This network was one of the first to pick up on declines of long-distance migrant birds, although because birds were coming from a broad swathe of central Europe and beyond, it was hard to pinpoint where the issues causing the fall in numbers might have arisen.

CES PROTOCOL Most current schemes follow a similar protocol to the British & Irish scheme in dividing the breeding season up into, approximately, 10-day periods, with one catch taken per period. The length of time schemes operate through the season does vary, though. In southern Europe, longer periods of migration mean, typically, only Each dot represents a site that contributes to the analysis; the darker the dot, the nine visits are possible to avoid skewing the longer the site has been operational. results by catching lots of birds that are just passing through. In Sweden and Finland, the season also starts a bit later, but mostly to look at how birds might respond to because northern sites may still be under changing climates. several feet of snow in May! The comparison provided by northern The five species most commonly caught and southern sites can help us understand across Europe will be very familiar to how northern populations may cope with British ringers: Reed Warbler, Blackcap, future changes. Analyses so far suggest Willow Warbler, Blue Tit and Great Tit. that individuals are well adapted to the Reed Warbler tops the list in nearly all conditions currently prevailing on a site, countries (though in Britain & Ireland it even though those conditions might be NIGHTINGALE comes second) with the notable exception of quite different in different parts of Europe; Some of the species Finland, where it has a restricted range. populations as a whole may not be able to commonly caught respond as quickly to new conditions as across continental RESULTS had been thought, however. This highlights Europe might be a little Of course, CE sites tell us not just about the need for local habitat management, unexpected. In France the number of adult and juvenile birds to ensure populations are as resilient as and Spain, Melodious that might be present on a site, but also possible. Warbler makes it into something about how good a breeding As the data set continues to grow, the top 10, as does season each species may have had. The fact so will our ability to tease apart the Nightingale. This is that we recapture individuals also gives us patterns contained within it, improving particularly poignant information on survival. This is valuable our knowledge of the issues facing bird as, whereas we were because then we start to understand some of populations today. We can finish recording able to produce a the processes that drive population change the details on that Blue Tit and enjoy national CES trend for (is it number of young fledging, or the our first coffee, knowing that our early Nightingale until 2001, propensity for birds to die that causes overall morning efforts help, in a small way, our now it is caught (in numbers to increase or decrease?). So far, understanding of how to make the world a small numbers) on data from CE sites have been used primarily better place for our birds. only a handful of sites.

Spring 2018 LIFECYCLE – 37 PUBLICATIONS | Delivering scientific outputs from the data you collect

Using your data

This feature highlights some of the scientific papers that have been produced using the data that you collect through the Ringing Scheme and the Nest Record Scheme. Pied Flycatcher, by John Harding/BTO; Wood John Harding/BTO; by Pied Flycatcher, Warbler & Whinchat, by Edmund Fellowes/BTO & Warbler

NO EFFECT OF GEOLOCATORS ON IDENTIFYING NEST PREDATORS OF NEST MONITORING BEST PRACTICE PIED FLYCATCHERS WOOD WARBLERS FOR WHINCHATS

Geolocators are proving an increasingly British Wood Warblers have undergone Nest recorders are always careful to popular method of studying migration. a serious decline over many decades minimise disturbance so as not to These relatively cheap devices record and are now largely restricted to upland influence nest outcomes and bias the information, about light levels and woods. Nest predation has been mooted data they are recording. The very act time of day, which can reveal the as a possible factor in their decline, and of visiting a nest has the potential bird’s location during migration this study monitored 434 nests in Mid to influence bird behaviour and once the device has been retrieved. Wales, Devon and the New Forest to could leave clues to attract predators, Miniaturisation of geolocators means examine breeding success in relation and so it is vital to understand and that they can now be fitted on small to vegetation and nest concealment. minimise these risks to ensure safe and passerines, using a Rappole harness, Half of the nests (51%) failed to fledge reliable nest studies. To address this but understanding the possible negative any young, mostly due to predation question, researchers studying breeding impacts of geolocators on welfare is (42% of all nests). Cameras at 144 Whinchats on Salisbury Plain split essential. This study looked at the nests showed that the major culprits their nest sample into two groups of effects of fitting 0.32-g tags on male in all regions were birds, particularly high- and low-intensity nest checks Pied Flycatchers in Devon. Short-term Jays and Buzzards, and avian predators to compare the nest survival rates. impacts were assessed by comparing the accounted for 45% of predation. They found that the survival of nests rate of nestling feeding visits by tagged Badgers, small rodents (including Grey examined every two days during the egg males and a control group of untagged Squirrel) and Foxes were the most phase was no different to that of nests birds with a similar capture history, significant mammalian predators, and that were checked only from a distance while long-term effects were measured two nests were predated by Adders. so as to avoid disturbance until the by comparing the return rates and Nests were slightly more successful expected hatching date. Furthermore, arrival dates of both groups of males in when situated among greater ground nest checks during the nestling period the following spring. The researchers cover but vegetation management was disrupted adult feeding visits for a found no differences between groups thought unlikely to have a strong- maximum of only 20 minutes, which in relation to any of the potential enough effect on predation to assist was considered highly unlikely to impacts monitored. They conclude Wood Warbler conservation, except affect chick survival. The researchers that fitting lightweight geolocators to in extreme cases of sparse cover, e.g. conclude that visiting nests every two small passerines can be safe, but that resulting from over grazing. In the New to three days had a negligible effect tagging studies of new species should Forest, where grazing pressure is severe, on Whinchat breeding success, but incorporate a control group to test for the probability of nest predation was stress the importance of minimising potential problems. high enough (72%) to threaten local disturbance in nest studies wherever populations. possible.

Bellamy, P.E. et al. (2018) Nest predation and the influence of habitat structure on nest predation of Bell, S.C. et al. (2017) No short- or long-term Wood Warbler Phylloscopus sibilatrix, a ground- Border , J.A. et al. (2018) Nest monitoring does not effects of geolocator attachment detected in Pied nesting forest passerine. Journal of Ornithology affect nesting success of Whinchats Saxicola rubetra. Flycatchers Ficedula hypoleuca. Ibis 159, 734–743. 159, 493–506. Ibis doi: 10.1111/ibi.12574

38 – LIFECYCLE Spring 2018 Adverts, courses and conferences | NOTICES

Noticeboard

ADVERTS 2018 TRAINING COURSES

RINGING OPPORTUNITY IN PORTUGAL Experienced ringers are needed to Further details of ringing courses for current ringers can be found on the ringers-only ring during autumn migration with A pages of the BTO website. Further details of NRS courses can be found on the website Rocha in the Algarve. A or C ringers at: www.bto.org/nrs-training are welcome from 1 Sept until 15 Nov 2018 to ring mainly migrating passerines as well as resident species. Trainees may Further details of bird identification and survey techniques training courses run by the come if accompanied by an A-permit BTO can be found on the Events pages of the BTO website at: www.bto.org/news- holder. Ringers are responsible for their events own travel costs and are asked to pay a reasonable charge for accommodation and full board if required (www.arocha.pt/ Ringing Courses en/centre/accommodation/). Contact Marcial Felgueiras: [email protected] 26–29 July: Chew Valley RS Ringing Course, nr Bristol / Contact: Bob Medland - FULLY BOOKED RINGING OPPORTUNITY IN GAMBIA 1–5 August: Icklesham Ringing Course, East Sussex / Contact: Gary Clewley Ringing opportunity for experienced A or C ringers in the Gambia on a one- or 9–12 August: Sandwich Bay Bird Observatory Ringing Course, Kent / Contact: Ian two-week trip from Nov to Mar. To apply, Hunter email: [email protected] 7–10 September: Gower Ringing Course, Swansea / Contact: Kelvin Jones POTTER TRAPS FOR SALE 13–16 September: Isle of Wight RG Ringing Course – for all ringers (including Two sizes (12” & 16”) also Chardonneret experienced trainees) / Contact: Anthony Roberts and other traps on request. Please contact John Mawer on 01652 628583 or via email [email protected] CONFERENCES

16–18 November: Scottish Ringers’ Conference, Carrbridge, Inverness-shire 7–9 December: BTO Annual Conference, Swanwick, Derbyshire

THE 2018 CES VISIT PERIODS

Visit First Date Last Date No of Days 1 Thursday 3 May to Saturday 12 May 10 2 Sunday 13 May to Wednesday 23 May 11 CONTACTS 3 Thursday 24 May to Saturday 2 June 10

Nest Record Scheme: [email protected] 4 Sunday 3 June to Wednesday 13 June 11 Ringing Scheme: [email protected] 5 Thursday 14 June to Saturday 23 June 10 Constant Effort Sites: [email protected] 6 Sunday 24 June to Wednesday 4 July 11 Retrapping Adults for Survival: [email protected] 7 Thursday 5 July to Saturday 14 July 10 Colour ringing: [email protected] 8 Sunday 15 July to Wednesday 25 July 11 Ringing data submissions: [email protected] 9 Thursday 26 July to Saturday 4 August 10 Licensing (general): [email protected] Schedule 1: [email protected] 10 Sunday 5 August to Wednesday 15 August 11 Special Methods: [email protected] 11 Thursday 16 August to Saturday 25 August 10 Ringing sales: [email protected] 12 Sunday 26 August to Wednesday 5 September 11

Spring 2018 LIFECYCLE – 39 Monitoring priorities: Little Owl Although unlisted on the Birds of Conservation Concern due to its status as an introduced species, Little Owl numbers have declined by 57% since Breeding Bird Survey monitoring began in 1995. Read on to find out how you can help our smallest owl species. Little Owl, by Prashant Meswani/BTO Little

CURRENT KNOWLEDGE be more successful than trying to attract readily to nest boxes, their breeding Little Owl numbers have undergone the species to a previously unused area. territory size (35+ hectares) means that a steep decline since the mid-1980s. Recent research has shown that Little a successful project will require a large Evidence identifying the cause of the Owls respond well to sound lures, study area. They are, however, easy to decline in the UK is sparse; however, so this method can be used to locate catch as they tend to remain in the box demographic data from across Europe territories and guide placement. Little when it is checked. Currently, there is suggest declines may be linked to falling Owls will use large boxes with a 70-mm only one active RAS on Little Owl; 61 rates of juvenile survival, possibly hole, or chimney-type boxes, but prefer of the 66 adult Little Owls ringed in due to loss of habitat and changes in boxes with a tunnel-style entrance and 2016 were ringed through this project. farming practices. Current British a dark nesting chamber, which can be Additional projects would therefore demographic information comes created via the use of baffles. Boxes can help to provide a better understanding from limited geographical areas and be sited at any height providing it is of survival rates on a national scale. generally involves small sample sizes, free from predation and interference by although there is a large-scale project in humans or grazing cattle. In the past Project Owl Lincolnshire. five years, between 150 and 200 nest We plan to use funds from the BTO records have been received each year for Owl Appeal to improve our knowledge HOW CAN YOU HELP? Little Owl, with between 340 and 500 of Little Owls, to increase the amount Erect nest boxes pulli ringed annually. of demographic data collected and the Little Owls will use nest boxes in areas geographical range of local studies. The where natural cavities are scarce. As it is Start a RAS Appeal is going well but we have some a sedentary species, placing a box in an Little Owl is a priority species for RAS. way to go to reach our target. Find out area with a known territory will usually Although this species can take quite more at www.bto.org/project-owl

` CBC/BBS index UK 1966­–2016 Fledglings per breeding attempt Laying date 1966–2016 400 1966–2016 130 3 300 120 2

200 1 110

0 100 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 1970 1980 1990 2000 2010 1970 1980 1990 2000 2010

Graphs shown are taken from the BirdTrends report (www.bto.org/birdtrends), where results from the Ringing Scheme and Nest Record Scheme are published annually.