Skip to content

Research at St Andrews

GPS tracking reveals rafting behaviour of Northern Gannets (Morus bassanus): implications for foraging ecology and conservation

Research output: Contribution to journalArticle


Matthew Ian Daniel Carter, Samantha L. Cox, Kylie L. Scales, Anthony W. J. Bicknell, Matthew D. Nicholson, Kelly M. Atkins, Greg Morgan, Lisa Morgan, W. James Grecian, Samantha C. Patrick, Stephen C. Votier

School/Research organisations


Capsule:  Three quarters of tracked Northern Gannets (Morus bassanus) at Grassholm gathered in rafts around the colony, concentrated within a recently designated at-sea Special Protection Area (SPA), but rafting was not correlated with foraging effort.
Aims:  To investigate the incidence, distribution and foraging implications of Northern Gannet rafting behaviour in waters adjacent to a large colony.
Methods:  Using bird-borne global positioning system (GPS) loggers we reconstructed at-sea movement and used a speed filter to identify rafting behaviour within 10 km of the colony. We mapped the spatial distribution of rafting events from 160 breeding individuals over 5 years, and investigated the relationship between foraging effort (trip duration and total distance travelled) and the presence/absence of rafting.
Results:  On average, 74% of tracked birds engaged in rafting. Of the 381 foraging trips analysed, rafting was recorded on 237 (62%). Birds were more likely to raft on outbound (224 trips, 59%), than inbound journeys (38 trips, 10%). Presence/absence of rafting did not correlate significantly with foraging trip distance or duration nor with duration of nest attendance. The majority of rafting was concentrated in a 2-km radius around the colony within a recently designated seaward SPA extension. Birds showed low individual repeatability in rafting, although there was lower variation within, than among, individuals.
Conclusion:  Our results show that rafting is important for breeding gannets on Grassholm, and a recently designated at-sea SPA encapsulates the core distribution of rafting. Rafting did not appear to be correlated with foraging behaviour. Given the dearth of literature on rafting and the wealth of GPS tracking data for seabirds, we suggest that similar research be conducted elsewhere to further elucidate the ecological and applied significance of this behaviour.


Original languageEnglish
Pages (from-to)83-95
Number of pages13
JournalBird Study
Issue number1
Early online date10 Feb 2016
Publication statusPublished - 2016

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by author

  1. Marine protected areas show low overlap with projected distributions of seabird populations in Britain and Ireland

    Critchley, E. J., Grecian, W. J., Kane, A., Jessopp, M. J. & Quinn, J. L., Aug 2018, In : Biological Conservation. 224, p. 309-317 9 p.

    Research output: Contribution to journalArticle

  2. Understanding the ontogeny of foraging behaviour: insights from combining marine predator bio-logging with satellite-derived oceanography in hidden Markov models

    Grecian, W. J., Lane, J., Michelot, T., Wade, H. M. & Hamer, K. C., 6 Jun 2018, In : Journal of the Royal Society Interface. 15, 143, 9 p., 20180084.

    Research output: Contribution to journalArticle

  3. Man-made structures and Apex Predators: Spatial interactions and overlap (MAPS)

    Grecian, W. J., Masden, E. A., Hammond, P. S., Owen, E., Daunt, F., Wanless, S. & Russell, D. JF., Jan 2018, INSITE.

    Research output: Book/ReportCommissioned report

  4. Search and foraging behaviors from movement data: a comparison of methods

    Bennison, A., Bearhop, S., Bodey, T. W., Votier, S. C., Grecian, W. J., Wakefield, E. D., Hamer, K. C. & Jessopp, M., Jan 2018, In : Ecology and Evolution. 8, 1, p. 13-24 12 p.

    Research output: Contribution to journalArticle

  5. Intrinsic and extrinsic factors drive ontogeny of early-life at-sea behaviour in a marine top predator

    Carter, M. I. D., Russell, D. J. F., Embling, C. B., Blight, C. J., Thompson, D., Hosegood, P. J. & Bennett, K. A., 14 Nov 2017, In : Scientific Reports. 7, 1, 14 p., 15505.

    Research output: Contribution to journalArticle

Related by journal

  1. Factors determining the frequency and productivity of double brooding of Barn Owls Tyto alba

    Jackson, P. & Cresswell, W., 2017, In : Bird Study. 64, 3, p. 353-361

    Research output: Contribution to journalArticle

  2. Nest site selection and patterns of nest re-use in the Hooded Crow Corvus cornix

    McIvor, G. E. & Healy, S. D., Sep 2017, In : Bird Study. 64, 3, p. 374-385

    Research output: Contribution to journalArticle

  3. High site fidelity in Northern Wheatears Oenanthe oenanthe wintering in Africa revealed through colour marking

    Blackburn, E. & Cresswell, W. R. L., 2016, In : Bird Study. 63, 2, p. 284-288

    Research output: Contribution to journalArticle

  4. Vegetation structure influences foraging decisions in a declining grassland bird: the importance of fine-scale habitat and grazing regime

    Murray, C., Minderman, J., Allison, J. & Calladine, J., 2016, In : Bird Study. 63, 2, p. 223-232

    Research output: Contribution to journalArticle

Related by journal

  1. Bird Study (Journal)

    Will Cresswell (Editor)

    Activity: Publication peer-review and editorial work typesEditor of research journal

  2. Bird Study (Journal)

    Will Cresswell (Member of editorial board)
    2001 → …

    Activity: Publication peer-review and editorial work typesEditor of research journal

ID: 249951432