The decline of the WillowTit in Britain

Alex l. G. Lewis, Arjun Amor, Elisabeth C. Chormon ond Finn R. P Stewort

ABSIMCT Numbers of the BritishWillowTit montonus kleinschmidti have decreased dramatically in recent decades.This paper outlines the three main hypotheses for the decline - increased competition, increased predation and changes in habitat availability - and describes the fieldwork and analyses undertaken to try and understand its cause.The results so far are not conclusive but indicate that the loss of young, damp woodland may have been important. Possible positive management strategies are suggested.

Introduction the first study to observe such a high number of Ronge ond habitot natural nests in Britain and thus provides an The British race of the Willow Poecile insight into the species'breeding ecology. montanus kleinschmidti is found in England, Willow Tits remain in their territories from Wales and parts of southern Scotland, including their first breeding year and start to sing in Dumfries & Galloway and North Lanarkshire lanuary when the weather is good (Maxwell (Clyde). The species as a whole is found 2007). Between April and May, they excavate a throughout much of the Western Palearctic and nest hole in dead wood. The most frequently east through northern Asia as far as fapan, where chosen tree species in the Midlands study area it is found largely in boreal forest with were willow Salix spp. (n=20), E\der Sambucus (Snow 1954; Alerstam et aL 7974; Snow & niger (n=70) (plate 21 1) and Silver Birch Betula Perrins 1998; Sellers 2002). A recent study in pendula (n=16) (plate 212),bttt nests were also northern Finland (Sitrczyk et a\.2003) showed found in Alder Alnus glutinosa (n=3), Hawthorn that in a 'mosaic forest landscape', Willow Tits Crataegus monogyna (n=2), Hazel Corylus preferred mature woodland (and pine bogs) and ayellana (n=2), Wild Cherry Prunus ayium avoided young stands. In Britain, however, the (n=1) and a (n=i). The nest hole is species is associated almost exclusively with excavated in either a dead tree or a dead part of early successional habitats such as those found a live tree, or occasionally in a felled trunk (p1ate along river valleys, overgrown flooded gravel- 213). Wiilow Tits can nest successfully in a trunk pits and wet woodland (Snow & Perrins l99B). with a diameter as small as 5 cm (measured at the part of the trunk corresponding to the base Breeding ecology of the nest chamber), although the mean Three separate but related studies of Willow Tits diameter recorded was 12 cm. were commissioned by the RSPB and took place Willow Tits line their nests with material such in 2005 and 2006, and form the basis of this as feathers, hair, thin strips of bark and review. One of these was carried out in the the fluf$' seeds from the heads ofbthrsh Typha Midlands (South Yorkshire, Derbyshire and (plate 214). The female incubates for approx- Nottinghamshire) and involved the location and imately 14 days (Maxwe1l 2007). Of 56 nesrs observation of 56 Willow Tit nests during the studied, it was possible to inspect only 20 trvo breeding seasons (Lewis unpubl.). This was internally (with an endoscope; plate 215) so that

386 . o Erirish 102 July 2009 . 386-393 The decline of the Willow Tit in

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l-2a Willow Poecile 2l 3. Tit montonus nests in Elder Sombucus niger (21 I ), Silver Birch Betuto pendula (212) and a felled Hawthorn Crotoegus monogyno (213), Nottinghamshire, April 2006.

clutch size could be determined. Clutch size was remain in the breeding territory all year roulrd. + found to be 8.8 0.4 (mean + I s.e.) and this was The few ringing reco\reries for this species not related to tree diameter (as measured above). support the finding t1.rat Willow Tits are In all cases, other than that described in Lewis & sedentary (but that juveniles in late summer or (.2007), Daniells i rvas impossible to calculate autumn will occasionally move more than 5 km; brood size and number of fledglings owing to: Sellers 2002). (i) the way that the chicks were invariably sitting on top of one another inside the chamber; and Populotion status (ii) the need to avoid excessive disturbance that An analysis of Con"rmon Birds Census (CBC) and prolonged viewing may have caused. Breeding Survey (BBS) data has shorvn that After the eggs hatch, the chicks remain in the the British Willow Tit underwent a drarnatic nest for approximately 18 days (plate 216). Once decline of880/o betrveen 1970 and 2006 (Eaton et fledged (plate 217), they remain in the al. 2008). Ringing data provide further evidence of immediate area for up to 20 days, while they a substantial population decline (Perrins 2003). In continue to be fed by both parents (Maxwell fact, of all the species mor.ritored adequately by the 2007). At the end of the breeding season, British BBS, the Willow Tit showed the greatest decline Willow Tits differ from their European (77o/o,1994 2007; Risely et a\.2008). The Repeat counterparts ir-r that they do not form gregarious Woodland Bird Survey, which looked at social groups, neither rvith conspecifics nor with population changes in woodland habitat only, also other tit species (Perrins 1979; Sellers 2002), and recorded a severe decline, of 7070 between the mid

. . British Eirds I 02 Juty 2009 386-393 387 The decline of theWillowTit in Britain

1980s and 2003/04 (Hewson efaL 2007). As well as losing a nest hole following its completion can a reduction in numbers, the Willow Tit has result in breeding failure. Between 1995 and suffered a marked contraction in its range in 2000, Maxwell (2002) monitored 30 Willow Tit Britain and has been iost entirely from many pairs using both natural nests and nestboxes. He counties (Gibbons et al. 1993 Smith er al. 1993). lound lhat only ten ofthese pairs were success- Owing to its population decline, the Willow Tit fu1. Of the 20 unsuccessful pairs, 18 had their appears on the UK's 'Red list' of birds of nest cavity taken over by Blue Tits and two by conservation concern (Eaton ef al.2009) and is a Great Tits. Blue and Great Tit populations have priority species in the UK Biodiversity Action increased in the UK between 1970 and 2006 Plan. However, despite the decline in numbers and (B1ue Tits by 33o/o and Great Tits by giolo) range contraction, Willow Tits still appear to be (Eaton ef al. 2008). Consequently, interspecific doing well in parts of the Midlands. Consequently, competition for nest-sites may have increased much of the recent work has focused on these and contributed to the Willow Tit's decline. apparently stable populations. Predotion

Potential threots t o Willow Tit populotions Once a nest hole has been excavated and lined, Research into the decline of the Willow Tit has Willow Tits can still be noisy around their focused on three hypotheses: increased breeding site, leaving them vulnerable to competition, increased predation and habitat detection by Great Spotted Woodpeckers change. Dendrocopos major, whrch are accomplished at extracting prey from rotten wood (Wesolowski Competition 2002; Fuller et aI.2005). This species will destroy The excavation of a nest hole can be a noisy a Willow Tit nest with ease and take the eggs or activity, as both birds often call repeatedly to chicks (Lewis unpubl.) (plate 218). Willow Tits each other. Typically, the process is also visually are single-brooded and if predation occurs at obvious as it involves much physical activity and the chick stage, the pair is extremely unlikely to continual production of small wood chippings. breed again that year. Even if predation occurs at An excavating Willow Tit pair is thus vulnerabie the egg stage, the pair will have limited resources to detection by competitively superior Blue (of time and energy) for another attempt. Cyanistes caeruleus and Great Tits Parus major.If Numbers of Great Spotted Woodpeckers have either of these species finds a Wil1ow Tit nest increased dramatically in the UK (by 3l4o/o ho1e, they can oust the occupants with little between 1970 and 2006; Eaton et al.2008), and difficulty (Maxwe1l 2002). Excavating a nest hole Willow Tits may have suffered a corresponding is a time- and energy-consuming process and increase in predation rate.

Hobitot Willow Tits are traditionally associated with damp, scrubby arers in Britain (Perrins 1979; Snow & Perrins 1998). Despite the steep pop- ulation decline, they can still occur dt relatively high densi- ties in some brownfield sites and disused gravel-pits, where such habitat is often charac- teri:tic (plate 2 l9) (Lewis unpubl.). However, these disused industrial sites have : become less common in ! recent decades, having been e lost to (for example) urban development and agricultural 2 I 4. EightWillowTit Poecile montonus chicks in a nestbox,Wiltshire, May clearance (Ban 2005.The bedding is made up of feathers and thin strips of bark. et aI.1993).

388 Eritish Birds 102 . July 2009 . 386-393 The decline of the Willow Tit in Britain

This apparent wasteland does not have the same unoccupied patches represent unfavourable perceived biodiversity value as more established habitat; in areas which are sparsely popuiated habitats such as woodland (Mortimer er al. owing to factors other than habitat (such as 2000) and the loss of large areas of such scrub predation), many favourable sites may be unoc- could be driving the Willow Tit's deciine. cupied and thus wrongly classified as unfavourable. A large number of habitat vari- Iesting the hypotheses ond exploringthe ables were quantified (inciuding tree diameter, couses ofthe decline tree-stem density and tree species composition, Data analysis canopy cover, soil-water content, dead-wood Siriwardena (2004) showed that the major abundance and vegetation cover at varying decline in Willow Tit numbers had occurred in height bands) in both occupied and unoccupied woodland and farmland, and that populations sites, and in areas within each occupied site in wet habitats had remained stable. In addition, where Willow Tits were present and absent. no significant negative relationships were found The large-sca1e study (Lewis et aI.2007) took between the abundance of Willow Tits and place throughout central, southern and eastern numbers of Great Tits, Blue Tits or Great England. It aimed to determine whether nine Spotted Woodpeckers over the same time period woodland sites that were known to have been (apart from between Willow Tits and Great abandoned by Willow Tits (five years or more Spotted Woodpeckers on farmland; see below). previously) differed from nine that were still Siriwardena (2004) concluded that further occupied, in terms of competitor numbers, research, particularly into the possible role of predator numbers and/or habitat. The numbers habitat in the species' demise, was needed, of Blue Tits, Great Tits and Great Spotted prompting the RSPB to undertake the three Woodpeckers were recorded and habitat research projects described here. In addition to measurements taken. These measurements were the Midlands breeding study, a small-scale study taken around past or present Willow Tit was carried out to investigate Willow Tit locations rather than throughout the wood, in habitat selection by comparing occupied and order to ensure that the habitat sampled was in unoccupied woods in an area of north a relevant area. Nottinghamshire with a relatively high density In terms of habitat, both of these studies of Willow Tits. This project also looked at showed that occupied sites had a significantly differences in habitat within indivrdual woods, higher soil-water content than unoccupied or between occupied and unused areas. A separate, abandoned sites. In addition, the small-scale larger-scale study tested the competition, study showed that occupied sites were of a predation and habitat-change hypotheses outlined above, by comparing woods that had been abandoned by Willow Tits with those that were still occupied. These two studies used the same basic fie1d methodology, but at different geographical scales.

The smoll- ond lorge-scole studies The small-scale study tLewis et al. in press) was carried out in north Nottinghamshire. in o o an area of 18 x 26 km where d Willow Tits still occur in good Iq numbers. The apparent stabil- .v ity and relatively high densiry 2 1,5. An endoscope is used to inspect the contents of aWillowTit Poecile oi Willow Tils in this region montonus nest at Bennerley Marsh, Nottinghamshire, May 2006. One person increases the probability that is directing the fibre-optic tube while the other views the chamber contents.

. Britjsh Birds I 02 July 2009 . 386-393 389 r significantly earlier successior-ral stage (defined The Midlonds study by a combination of factors indicative of tree age, Results from the Midlands study showed that, of including tree diameter and canopy height) than the 56 Willow Tit nests monitored over two unoccupied sites. Furthermore, Wil1ow Tits breeding seasons, breeding success was high tended to be found in most young patches of with only 17 nests (30%) failing. Breedir.rg woodland but rvere also present in older patches success was similar between the two breedir-rg if these patches had moist soils. However, they seasons (2005: 660/o X lo/o (n=24),2006:72o/o + were almost completely absent from older, drier B% (n=32)). woods. In addition, unoccupied sites tended to predation caused ten of the 17 failures (seven at have more coniferous trees. Within occupied the chick stage and three at the egg stage). There woods, Wil1ow Tits were located in areas with was no evidence of any of these pairs re-nesting iess Bracken Pteridium aquilinum and more following predation. Only one nest failure was cover between 2 and 4 m in height - the mid- due to mammal predation (by a Weasel Mustela level understorey. The large-scale study found no nivalis;Lewis & Daniells 2007), and no failures differences in numbers of Blr-re Tits, Great Tits due to ousting by competitors were recorded. and Great Spotted Woodpeckers between The cause of failure for six nests was unknown. occupied and abandoned sites. I nterp retotio n of results The sma11- and large-sca1e srudie: pror ide quantitative \upport for the observalion that Wiliow Tits in Britain select early successional deciduous woodland and that they are often associated with damp habitats (Snow & Perrins 1998). Their prefer- ence for damp woodland (that with a relatively high soil- sater content) was shown in both studies and for early successional woodland in the snall-scale study. The fact that <' ! abandoned sites tended to be o €.! drier than occupied sites suggests that drier sites are either less likely to retain their Willow Tits or that they have become drier and lost them as a result. In the small-scale study, measurements of tree diarneter lrom occupied site> showed that, according to Forestry Commission yield models, stands between 15 and 25 years old had the highest probability of occupancy. Both studies also

.2 supported Siriwardena's (200a) finding that Willow J Tits have declined dramat- ically in woodland and 216 Poeci/e montonus & 217. A colour-ringedWillowTit bringing farmland but not in damp caterpillars back to chicl

. 390 British Birds I 02 luly 2009 . 386-393 The decline of theWillowTit in Britain species' association with young, damp woodland better in) habitats which support iower are currently being investigated (see below). population densities of this predator. Such sites may offer greater nesting The results do not show that the Great opportunities: willow and birch are more likely Spotted Woodpecker has been instrumental in to occur in greater cluantity in damp conditions the Willow Tit's decline. However, an increase in while higher rates of timber decay in such areas woodpecker numbers within the Willow Tit's may facilitate nest-hole excavation. Sr-rch preferred habitat would be 1ike1y to increase conditions may also present Willow Tits with predation rates. Moreover, although no overall lai ourable leed ing opport uni Lies. relationship was found between the \,\,'illow Tit's Neither study was able to establish the reason decline and the Great Spotted Woodpecker's for the Willow Tit's decline with certainty, but increase between 1970 and 2005, Siriwardena the finding that abandoned sites were (2004) did find a significant negative significantly drier than occupied sites provides relationship between the two species orr perhaps the strongest clue that the drying out of farmland sites. Willow Tit habitat ir.r farmland woodland could be driving the species'decline. areas usually consists of small, scrubby It is impossible to quantift the decline in early woodlands, orchards or hedgerows and Amar successional, damp woodland over the last few et al. (2006) showed that Great Spotted decades; no figures exist for either past or Woodpecker numbers had increased by 440o/o in present coverage (UK Wet Woodland small farm woods over the past 20 years (eight Biodiversity Action Plan wwwukbap.org.ul<). times more than in other broadleaved woods). Hower.er, various factors known to contribute to The same study showed that the probability of the loss of such woodiand (such as the lowering an increase in numbers of the Willow Tit's most of water tables, pollutior-r from agricuitural run- significant predator was higher in younger off and climate warming) are all known to have woodlands - the Willow Tit's preferred habitat. increased in recent years (UK Wet Woodland Nonetheless, in the large-scale analysis no Biodiversity Action PIan). difference was found in Great Spotted \;\&y do Wiilow Tits prefer young, damp Woodpecker abundance between woods woodland? Early successional woodland occupied and abandoned by Willow Tits. supports proportionately fewer Blue and Great Tits; for example, Smart er al. (2007) showed Ongoing ond future reseorch that Blue Tits were more abundant in older Investigations into habitat selection by Willow woods, which contain more natural cavities for Tits are ongoing and have now been extended to nest-sites. Competition for nest-sites is not new, cover more of the UK. Establishing consistent but mav well have increased in recent vears as habitat preferences across a wide area should populations of Blue and Great Tits have grown. Although no direct link was found between abundance oI oLher liL species and the Willow Tit decline (Siriwardena 2004), competi- lors may.till be influencing the Willow Tit's selection of habitat. Great Spotted Woodpeckers were the main nest predator olWillow Tits in the Midlands study. This woodpecker requires trees with a minimum diameter of ercavation lB cm for nest .e (Smith 1997) and young ! woodland will thus support lower densities (Kosihski 2006). Willow Tits may 2 I 8. Willow Tit Poecile montonus nest in willow So/ix destroyed by G reat S potted Wood pe cker D e n d rocop os mojor, Ogston Res e rvo i r, D erbys h i re, therelore select (or survive May 2004. All the chicks were eaten and the nest abandoned.

. Eritish Birds I 02 July 2009 . 386-393 39t of a structured survey) and such an assessment should be undertaken before and after any intervention.

lnterim manogement recommendotions Wet features Willow Tits are traditionaliy associated with wet woodland and the comparative studies showed that more Willow Tits o: were found at sites with a ! high soil-moisture content. Features such as ponds and Daneshill 219. Gravel-pits, Nottinghamshire, April 2006, a site where streams should therefore con_ several pairs ofWillowTits Poecile montonus stili breed successfully. tribute to making a site more improve our understanding of whether habitat favourable as Willow Tit habitat. loss has been responsible for driving the decline. Once the characteristics of suitable Willow Tit Young trees habitat are more clearly understood, it will be Willow Tits are traditionally associated with critical to establish whether a shortage of such early successional woodland and have been habitats exists where declines have been most shown to favour sites with trees between 15 and evident. If habitat is abundant, then other 25 years o1d. Managing an area to include factors must be responsible for the decline and substantial areas of such trees should enhance woodland management will not help. However, the prospects for Willow Tits. if a lack of suitable habitat appears to be instru- mental in the species'decline, such management The protection of brownfield sites lvill be crucial. Further analyses of key BTO data Brownfield sites in the Midlands often support (such as that from Constant Effort Sites and the high densities of Willow Tits, possibly because Nest Record Scheme) are also being undertaken such areas often support young trees and to improve understanding of any demographic waterbodies. These areas have minimal changes linked to the species'decline. protection from development and are therefore There are also several key areas relating to constantly at risk of being lost. As well as Willow Tit ecology that are worthy of further supporting Willow Tits, such areas provide study. Although the species appears to favour habitat for other Red-listed species such as the damp scrub and woodland, the reasons for this Br"rllfinch Pyrrhula pyrrhula, Turtle Dove remain unclear. As outlined above, this may Streptopelia turtur and Reed Bunting Emberiza reflect the physical structure of such habitat schoeniclus. Protection of such areas will help to resulting in reduced competition and/or nest maintain key populations of Wi11ow Tits. predation. However, it also may be related to food availability. Until more is known, in Nestbox plocement * o red herring? particular about the species'diet throughout the Neslbores are often put up in an attempt to year, establishing the importance of such habitat increase Willow Tit abundance and/or breeding will be difficult. success in an area. However, there is no evidence Given the current gaps in knowledge, the to suggest that dead wood is a limiting factor: no efficacy of any habitat management measures difference in dead-wood abundance was found (such as provision of nestboxes, creation of wet between sites that had been abandoned by features and/or cultivation of areas of scrub) Willow Tits and those occupied by them (Lewis must be monitored carefully. A good estimate of et a\.2007).A survey ofthe River Clyde showed the number of Willow Tits at a site can be that the number of Willow Tit pairs had obtained by playing a recording of their call and declined by 50% between 2000 and 2003, yet no song at specific points throughout the site sl.rortage of dead wood was found (Maxwell (although this should be carried out only as part 2007). Recent habitat-related studies of

392 Brirish Birds I 02 . july 2009 . 386-393 The decline of the Willow Tit in Britain woodland have also shown that, overall, the n British wood and bird popuLat ons derlved from the RepeatWoodland Brd Survey./bls 149 (Supp.2): l4-28 dead-wood resource has ir-rcreased (e.g. Amar er Kosihsk, Z 2006 Factors affecting the occuTTence of aI.2007). A reduction in dead wood is therefore M ddle Spotted and Great Spotted Woodpeckers n unlikely to be the cause of the species' decline. If deciduous forests a case study from Po and. Ann. Zool. Fennici 13: L 9B-2 0. there is local concern that dead wood is lacking, Lewis, A. J G., & Daniells L. J. 2007. Weasel predating be measured (see Lewis ef al. the resource should Willow T t nest. Brit Birds I OO: 757. 2007) and compared with that of the occupied & - 2009 Second excavation causes WillowTit nest sites in the north Nottinghamshire population farlure Brit Buds la7: 15 146. A Cord j-P ec, D., & ThewL s R. l'1. 2007. Factors known Aman , where the availability of dead wood is influencing Willow Tit site occupancy: a compar son of not to be a problem. abandoned and occupied woods /bis 149:)05-713. , Dan ells, L.,Tay o; E, Gnce, P, & Smith, K. n press. Acknowledgments Factors nfluenc ng patch occupancy and wthin patch hab tat use in an apparent y stable popu ation of British Thrs study was funded by the Royal Soc ety lor the WlllowTits (Poeci/e montonus k/einschmidti). Bnd Study. Protection of Brds, Natural England (through the Action 2002. Nest-site competit on wrth Blue Tits and for Brrds n England Partnersh p) and Forestry Max"we , l. GreatTts as a possib e cause of declines in WillowTit Commission Engand.We are ertremely grateful to Ken numbers: observations n the Clyde area. Smth ofthe RSPB for guidance and a the landowners G/osg Nol )4:41 50 and managers who a lowed us access to thelr land 2007. Wlllow T t. n: Forrestei R. W, Andrews, . throughout the three year study.We aso thank Dane J., - lYclnerny, C.J., 14urray, R. D. YlcGowan, R.Y, ZonfrilLo, Cord -Piec, Laura Daniells, Derek Gruan Chris Hil Erica B., Betts, lY.W,lardine, D. C., & Grundy D. S (eds.). Morey, .lacqui Weir and Davld Wood for help wth the Ihe Birds of Scot/ond. SOC,Aberlady. fe dwork and all the volunteers who generousLy gave up Ylortimer S. R.,Turnen A. J., Brown,V K., Ful er: R. 1., Good t me to support the proledr n a variety ol ways. J E G., Bel,S.A.,Stevens, PA., Norris, D, Baled, N., & Ward, L. K.2000. Ihe Notrre ConservdtlonValue ofScrub References ln Bdtcin. JNCC Research Report 308, Peterborough. -[, Alerstam Nrlsson, S G., & U fstrand S. 974. N che Perrins, C. M. 1979. British lts. Collins, London d fferent ation dur ng w nter n woodland birds in 2003.The status ol Marsh and W llowTits n the UK southern Sweden and the island of Gotland. - Bnt. Blrds 96:4lB 476 Orkos 25:32 330. Risely, K., Nob e, D. G. & Bai e, S. R. 2008. The Breeding Amai:A., lewson, C Y,Thew s, R. ['1., Smth, K.W, Fu en Bird Survey 2AA/.BTa Research Report 50B,Thetford. R.J., Lindsell,J., Conway, G., Butle6 S, & lYacDonald, Se ers, R. f1.2002.Wil owTit. lnrWernham, C V,Toms, ['1. A. 2006. What's HopPening to ourWoodlond Birds? lY. P, Marchant I. H., CLarl<,1.A., S rwardena, C. M., & Lang term chonges in the populotions of'woodlartd birds Bai e, S. R. (eds,). The Mtgration Atlas: rnovements of the RSPB/BTO Research Report, Sandy/Thetford. birds of Brttain ond lreland. Poyse; London. Barn C.1., Bunce, R.G. H. Carke, R.T, Fu er: R. lY., Furse, S ffczyk, C., Brotons, L., Kangas, K, & OreL , M. 2003. Home [1 1.,Gi espe, M. K.,Groom, G. B. Hallam,C.J, fange sze ofW]lowTits: a Tesponse to winter habtat Hormung, M., loward, D, C. & Ness, lY.l. 1993. loss. Oeco/oglc 36:635 61). Countryside Survey 1990. Departrnent ofthe S r wardena, G, 2004. Poss ble ro es of hab tat, cornPetit on Env ronment, London. and avan nest predaton in the decline oftheW low Eaton, lY,A., Brown,A. [, Nobe, D. G., lYusgrove,A.]., T r Porus montanus in Britaln. Btrd Study 5 : I 93 202. S., Hearn, R. D., Aebischer: N. J., G bbons, D. W, Evans, A., & Smart, J.,TayLo; E., Amar: A. Smith K., B erman, Gregory R. D. 2009. Birds of Conservat on Concern 3: Carpente;J., Grice, P, Currie, F, Smithers, R., Fu ler: R., & the populaton status of b rds in the United Kingdom, Hewson, C. 2OO7 Hobitot Associations of Vy'oodland Channel lslands and lsle of Man. Brit. Blrds 02r Birds: implications for woodland morngement fur declining 296 34t. specles. RSPB Research Report No. 26, Sandy.

Balme[ D. E., Burton, N., Grrce PV, [lusgrove, A. J., Smth, K.W 997. Nest ste selecton of the Great -, !earn, R., HiLton, G., Leech D. Nobe, D. G. Ratcliffe, Spotted Woodpec

Alex I. G. Lewis and Elisabeth C. Charmsn, Conservation Science, RSPB' The Lodge, Sandy, BedJbrdshire SG19 2DL Arjun Amar, RSPB-Scotland, Dunedin House, 25 Ravelston Terrace, Edinburgh EH4 3TP Finn R. P. Stewart, The School of Biology, The [Jnit'ersity of Nottingham, University Park' Nottingham NG7 2RD ri\

393 British Birds I 02 ' July 2009 ' 386-393