John Calladine



Senior Research Ecologist, BTO Scotland 


Responsible for managing, developing and undertaking research projects relevant to Scotland, in particular the development of BTO Scotland’s portfolio of studies related to forest and moorland management.  


BSc (Hons) Ecology, University of Lancaster, 1979-1982
MSc (by research) ‘Colony attendance, nest site selection and breeding performance in the Herring and Lesser Black-backed Gull: implications for conservation management’, 1993-95. 
Honorary Lecturer in the School of Biological & Environmental Sciences, University of Stirling (since 2005) 

Research Interests/Responsibilities 

  • Direct and extensive experience of working on a range of applied conservation research and survey projects.
  • Extensive experience of interpreting survey results and reviewing for applied conservation purposes.
  • Involvement with practical land management issues and how they influence nature conservation interests.

Recent and current studies include: (i) long-term monitoring associated with moorland management; (ii) the bird communities in new native-type woodlands; (iii) bird-habitat relationships and the influence of restructuring the interface between conifer plantations and moorland and other aspects of plantation management; (iv) the development of survey methods for the monitoring of Short-eared Owls and for birds of alpine habitats in Scotland; (v) bird communities in short-rotation forestry energy crops; (vi) population changes in breeding waders on machair; (vi) reviews of the populations of predatory birds and the ecology of urban gulls in Scotland; (vii) studies on the winter ecology of some seed-eating birds; and (viii) studies on upland habitat selection by breeding Whinchats.

Other Information

An active bird ringer
Honorary Lecturer in the School of Biological & Environmental Sciences, University of Stirling (since 2005) 

Selected publications

Murray, C., Minderman, J., Allison, J. & Calladine, J. In press. Vegetation structure influences foraging decisions in a declining grassland bird: the importance of fine scale habitat and grazing regime. Bird Study.

Calladine, J., Bray, J., Broome, A. & Fuller, R.J. 2015. Comparison of breeding bird assemblages in conifer plantations managed by continuous cover forestry and clearfelling.   Forest Ecology and Management 344: 20-29.

Calladine, J., Humphreys, E.M. & Boyle, J. 2015. Changes in breeding wader populations of the Uist machair between 1983 and 2014. Scottish Birds 35: 207-215.

Calladine, J. 2015. Multi-scale associations with habitat, land use and change: Opportunities and limitations for Whinchats Saxicola rubetra in the uplands of Scotland.  In Bastian, H-V & Feulner (eds) Living on the edge of extinction in Europe.  Proceedings of the first European Whinchat Symposium, LBV Hof, Hembrechts. Pp 205-212.

Henderson, I., Calladine, J., Massimino, D., Taylor, J. & Gillings, S. 2014. Evidence or contrasting causes of population change in two closely related, sympatric breeding species the Whinchat Saxicola rubetra and Stonechat Saxicola torquata in Britain. Bird Study 61: 553-565.

Fuller, R.J. & Calladine, J. 2014.  Landscape transition through natural processes: implications for biodiversity of tree regeneration on moorland. BOU proceedings - Ecology and conservation of birds in upland and alpine habitats.

Calladine, J., Pakeman, R.J., Humphreys, E., Huband, S. & Fuller, R.J. 2014. Changes in breeding wader assemblages, vegetation and land use within machair environments over three decades. Bird Study 61: 287-300

Calladine, J., Critchley, C.N.R., Baker, D., Towers, J. & Thiel, A. 2014. Conservation management of moorland: a case study of the effectiveness of a combined suite of management prescriptions which aim to enhance breeding bird populations. Bird Study 61: 56-72.

Calladine, J., Bielinski, A. & Shaw, G. 2013. Effect on bird abundance and species richness of edge restructuring to include shrubs at the interface between conifer plantations and open moorland. Bird Study 60: 345-356..

Burton, N.H.K., Banks, A.N., Calladine, J.R. & Austin, G.E. 2013. The importance of the United Kingdom for wintering gulls: population estimates and conservation requirements. Bird Study 60: 87-101.

Calladine, J. & Morrison, N. 2013. Diurnal and nocturnal ranging behaviour by moorland breeding Short-eared Owl Asio flammeus in Scotland. Bird Study 60: 44-51.

Calladine, J. & Bray, J. 2012. The importance of altitude and aspect for breeding Whinchats Saxicola rubetra in the uplands: limitations of the uplands as a refuge for a declining, formerly widespread species? Bird Study 59: 43-51.

Calladine, J., du Feu, C. & du Feu, R. 2012. Changing migration patterns of the Short-eared Owl Asio flammeus in Europe: an analysis of ringing recoveries. Journal of Ornithology 153: 691–698.

Calladine, J. 2011. Seasonal variation in the apparent abundance of breeding birds in arctic-alpine habitats in Scotland: implications for their survey and monitoring. Bird Study 58:27-36

Calladine, J. & Morrison, N. 2010. The ranging behaviour and habitat selection by three Hawfinches Coccothraustes coccothraustes in late winter in Scotland. Ornis Fennica 87: 119-123.

Calladine, J., Garner, G., Wernham, C. & Buxton, N. 2010. Variation in the diurnal activity of breeding Short-eared Owls Asio flammeus: implications for their survey and monitoring. Bird Study 27: 89-99.

Fuller, R.J., Humphreys, E.M., Wilson, J.D., Hoccom, D. & Calladine, J. 2010. Changes in the breeding wader populations of the machair of the Western Isles, Scotland, between 2000 and 2007. Bird Study 27: 121-124.

Banks, A., Burton, N, Calladine, J & Austin, G. 2009. Indexing winter gull numbers in Great Britain using data from the 1953 to 2004 Winter Gull Roost Survey. Bird Study 56: 103-119.

Calladine, J. & Wernham, C. 2009. Extensive monitoring of rock ptarmigan Lagopus mutus in Scotland: a pilot to test the efficacy of using volunteer surveyors for monitoring arctic-alpine birds. Avocetta 33: 217-224.

Calladine, J., Garner, G., Wernham, C. & Thiel, A. 2009. The influence of survey frequency on population estimates of moorland breeding birds. Bird Study 56: 381-388.

Calladine, J., Humphreys, E.M, Jardine, D. and Strachan, F. 2009. Forestry thinning in commercial conifer plantations has little effect on breeding bird abundance and species richness in northern Scotland. Bird Study 56: 137-141.

Harris, C.M., Calladine, J.R., Wernham, C.V. & Park, K. 2008. Impacts of piscivorous birds on salmonid populations and game fisheries in Scotland; a review. Wildlife Biology 14: 395-411.

Park, K.J., Graham, K.E., Calladine, J. & Wernahm, C.V. 2008. Impacts of birds of prey on gamebirds in the UK: a review. Ibis 150: 9-26.

Calladine, J., Wernham, C. & Robertson, D. 2006. The ranging behaviour of some granivorous passerines on farmland in winter determined by mark-recapture ringing and by radio-telemetry. Ibis 148: 169-173

Calladine, J.R., Park, K.J., Thompson, K. & Wernham, C.V. 2005. Review of urban gulls and their management in Scotland. Report to the Scottish Executive.

Park, K.J., Calladine, J.R., Graham, K.E., Stephenson, C.M. & Wernham, C.V. (2005) The impacts of predatory birds on waders, songbirds, gamebirds and fisheries interests. A report to Scotland’s Moorland Forum. BTO Scotland & Centre for Conservation Science, Stirling.

Calladine, J. 2004. Lesser Black-backed Gull. pp 226-241 in: Mitchell, P.I, Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds) Seabird Populations of Britain and Ireland. T.& A.D. Poyser, London.

Calladine, J. 2002. Herring Gull. pp 369-372 in: Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds) The Migration Atlas: Movements of the Birds of Britain and Ireland. T. & A.D. Poyser, London.

Baines, D., Warren, P. & Calladine, J. 2002. Spatial and temporal differences in the abundance of black grouse and other moorland birds in relation to reductions in sheep grazing. Aspects of Applied Biology 67:245-252

Calladine, J., Baines, D. & Warren, P. 2002. Effects of reduced grazing on population density and breeding success of black grouse Tetrao tetrix in northern England. Journal of Applied Ecology 39: 772-780.

Aebischer, N.J., Browne, S.J. & Calladine, J.R. 2001. An update on population trends, breeding ecology and migration of British turtle doves. pp 20-32 in: Kassinis, N. & Panayides, P. (eds) Status, Management and Conservation of the Species Alectoris, Black Francolin, Thrush, Quail and Turtle Dove in the Mediterranean Region. Game Fund Service, Ministry of Interior, Nicosia.

Baines, D, Blake, K. & Calladine, J. 2000. Reversing the decline: Case studies of black grouse conservation in Great Britain. Cahiers d’Ethologie 20: 217-234. Proceedings of European Black Grouse Conference, Liege, September 2000.

Calladine, J., Baines, D. & Warren, P. 2000. Moorland restoration in the north of England: a conservation initiative for Black Grouse. Cahiers d’Ethologie 20: 521-532. Proceedings of European Black Grouse Conference, Liege, September 2000.

Calladine, J., Buner, F. & Aebischer, N.J. 1999. Temporal variations in the singing activity and detection efficiency of Turtle Doves Streptopelia turtur: implications for surveying. Bird Study 46: 74-80.

Calladine, J. 1997. A comparison of Herring Gull Larus argentatus and Lesser Black-backed gull Larus fuscus nest sites: their characteristics and relationships with breeding success. Bird Study 44: 318-326.

Calladine, J. 1997. The detection efficiency of color-banded Herring Gulls Larus argentatus and Lesser Black-backed Gulls Larus fuscus at the breeding colony: practical implications for the determination of adult survival rates. Colonial Waterbirds 20: 41-46.

Calladine, J. & Harris, M.P. 1997. Intermittent breeding in the Herring Gull Larus argentatus and the Lesser Black-backed Gull Larus fuscus. Ibis 139: 259-263

Calladine, J., Buner, F. & Aebischer, N.J. 1997. The summer ecology and habitat use of the Turtle Dove: a pilot study. English Nature research report No. 219.

Wanless, S., Harris, M.P., Calladine, J. & Rothery, P. 1996. Modelling responses of herring gull and lesser black-backed gull populations to reduction of reproductive output: implications for control measures. Journal of Applied Ecology 33: 1420-1432.

Calladine, J., Harris, M.P., Taylor, S. & Wanless, S. 1995. The status of the Eider on the Isle of May and other Forth islands. Scottish Birds 18: 1-10.

Harris, M.P. & Calladine, J. 1993. A check of the efficiency of finding colour-ringed Kittiwakes Rissa tridactyla.  Ringing and Migration 14: 13-116.

Calladine, J., Dougill, S., Harding, N. & Stroud, D.A. 1990. Moorland birds on the Campsie Fells, Touch Hills and west Ochill Hills, Stirling: Habitats, distribution and numbers. Forth Naturalist and Historian 13: 3-69.

Contact details

Email john.calladine [at]
BTO Scotland
School of Biological & Environmental Sciences
Cottrell Building, University of Stirling
Stirling FK9 4LA
Telephone: 01786 466 560
Fax:  01786 566 561