Journal of Ornithology

, Volume 147, Issue 2, pp 254–259

Migration Watch: an Internet survey to monitor spring migration in Britain and Ireland

  • Stephen R. Baillie
  • Dawn E. Balmer
  • Iain S. Downie
  • Karen H.M. Wright


The arrival patterns of summer visitors to Britain and Ireland were monitored from 2002 to 2004 using large numbers of birdwatching lists collected by Migration Watch, an Internet-based survey. Records were only accepted from registered observers, and procedures for data validation were implemented. We show here how data on the frequency of occurrence from birdwatching lists can be analysed to estimate the timing and duration of the migration period. Aerial insectivores showed clear species-specific arrival patterns, with sand martins arriving first, followed in succession by swallows, house martins and finally swifts. Wheatears showed two peaks of arrivals, one for the British population and one for passage migrants from Greenland. The progression of arrivals from south to north and variation in arrival timing between years were also demonstrated. The method offers considerable potential for studying migration phenology at large spatial scales, and within Britain and Ireland it is now being applied throughout the year within the BTO/RSPB/BWI BirdTrack project. It could potentially be implemented at a continental scale, at which it would provide an important tool for measuring the growing impacts of global climate change on bird populations.


Internet-based surveys Phenology Spring migration Species lists 


  1. Crick HQP, Dudley C, Glue DE, Thomson DL (1997) UK birds are laying eggs earlier. Nature 388:526CrossRefGoogle Scholar
  2. Crick HQP, Sparks TH (1999) Climate change related to egg-laying trends. Nature 399:423–424CrossRefGoogle Scholar
  3. Fewster RM, Buckland ST, Siriwardena GM, Baillie SR, Wilson JD (2000) Analysis of population trends for farmland birds using generalized additive models. Ecology 81:1970–1984CrossRefGoogle Scholar
  4. Harrison JA, Allan DG, Underhill LG, Herremans M, Tree AJ, Parker V, Brown CJ (1997) The atlas of Southern African birds. Birdlife S Afr vol 1:XliiiGoogle Scholar
  5. Hudson R (1973) Early and late dates for summer migrants. BTO Guide 15. British Trust for Ornithology, TringGoogle Scholar
  6. Huin N, Sparks TH (1998) Arrival and progression of the swallow Hirundo rustica through Britain. Bird Study 45:361–370Google Scholar
  7. Mason CF (1995) Long-term trends in the arrival dates of spring migrants. Bird Study 42:182–189CrossRefGoogle Scholar
  8. Newson SE, Woodburn RJW, Noble DG, Baillie SR, Gregory RD (2005) Evaluating the breeding bird survey for producing national population size and density estimates. Bird Study 52:42–54Google Scholar
  9. Riddiford N, Findley P (1981) Seasonal movements of summer migrants. BTO Guide 18. British Trust for Ornithology, TringGoogle Scholar
  10. Robinson RA, Learmonth JA, Hutson AM, Macleod CD, Sparks TH, Leech DI, Pierce GJ, Rehfisch MM, Crick HQP (2005) Climate change and migratory species. BTO Research Report 414. British Trust for Ornithology, ThetfordGoogle Scholar
  11. Southern HN (1938) The spring migration of the swallow over Europe. Br Birds 32:4–7Google Scholar
  12. Sparks TH, Bairlein F, Bojarinova JG, Hüppop O, Lehikoinen EA, Rainio K, Sokolov LV, Walker D (2005) Examining the total arrival distribution of migratory birds. Glob Change Biol 11:22–30CrossRefGoogle Scholar
  13. Walther G-R, Post E, Convey A, Menzel A, Parmesan C, Beebee TJC, Fromentin J-M, Hoegh-Guldberg O, Bairlein F (2002) Ecological responses to recent climate change (review). Nature 416:389–395CrossRefPubMedGoogle Scholar
  14. Wernham CV, Toms MP, Marchant JH, Clark JA, Siriwardena GM, Baillie SR (eds) (2002) The migration atlas: movements of the birds of Britain and Ireland. T & AD Poyser, LondonGoogle Scholar

Copyright information

© Dt. Ornithologen-Gesellschaft e.V. 2006

Authors and Affiliations

  • Stephen R. Baillie
    • 1
  • Dawn E. Balmer
    • 1
  • Iain S. Downie
    • 1
  • Karen H.M. Wright
    • 1
  1. 1.The NunneryBritish Trust for Ornithology (BTO)NorfolkUK

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