Skip to content

Research at St Andrews

The development and use of a method to fill time gaps in migration counts: seabird conservation applications.

Research output: Contribution to journalArticle

DOI

Abstract

In some conservation situations, there is a need for estimates of numbers of seabirds migrating past a specific site, such as sites of proposed offshore wind farms. Migration counts from points strategically located on the coast can be a reliable and effective method of reaching this goal. We propose a consistent and statistically robust method for estimating such numbers by generalized additive modeling of the numbers passing during periods when counts are interrupted. This procedure has the advantage of accounting for the effects of covariates, such as wind, on the counts in a flexible manner, potentially increasing accuracy and precision. We develop a reliable method of estimating precision, based on a parametric bootstrap, and applied a sensitivity analysis to our models to test their accuracy. We demonstrate the method with three species of seabirds migrating through the Strait of Gibraltar. Estimated numbers of the Northern Gannet (Morus bassanus) are similar to the estimated Atlantic population that winters in the western Mediterranean Sea, while for both Cory’s (Calonectris diomedea) and Balearic (Puffinus mauretanicus) Shearwaters they are greater than the current population estimates. These results have important implications in conservation and highlight the necessity for reestimation of the latter two species’ global population. Potential sources of biases include the constraint on detectability due to distance and the possibility of double counting due to local movements. To avoid overestimates, we suggest that values imputed for the gaps in counts be conservative.
Close

Details

Original languageEnglish
Pages (from-to)513-522
JournalCondor
Volume114
DOIs
Publication statusPublished - 2012

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

View graph of relations

Related by author

  1. Estimating group size from acoustic footprint to improve Blainville’s beaked whale abundance estimation

    Jorge, P., Marques, T. A., Mouriño, H., Thomas, L., Moretti, D., Dolan, K., Claridge, D. & Dunn, C., 31 Jul 2019, (Accepted/In press) In : Applied Acoustics .

    Research output: Contribution to journalArticle

  2. Decline towards extinction of Mexico's vaquita porpoise (Phocoena sinus)

    Jaramillo-Legorreta, A., Cardenas-Hinojosa, G., Nieto-Garcia, E., Rojas-Bracho, L., Thomas, L., Ver Hoef, J. M., Moore, J., Taylor, B., Barlow, J. & Tregenza, NI., 31 Jul 2019, In : Royal Society Open Science. 6, 7, 11 p., 190598.

    Research output: Contribution to journalArticle

  3. Population-level consequences of seismic surveys on fishes: an interdisciplinary challenge

    Slabbekoorn, H., Dalen, J., de Haan, D., Winter, H. V., Radford, C., Ainslie, M. A., Heaney, K. D., van Kooten, T., Thomas, L. & Harwood, J., Jul 2019, In : Fish and Fisheries. 20, 4, p. 653-685 33 p.

    Research output: Contribution to journalArticle

  4. Distance sampling in R

    Miller, D. L., Rexstad, E., Thomas, L., Marshall, L. & Laake, J. L., 9 May 2019, In : Journal of Statistical Software. 89, 1, 28 p.

    Research output: Contribution to journalArticle

  5. Estimating effective detection area of static passive acoustic data loggers from playback experiments with cetacean vocalisations

    Nuuttila, H. K., Brundiers, K., Dähne, M., Koblitz, J. C., Thomas, L., Courtene-Jones, W., Evans, P. G. H., Turner, J. R., Bennell, J. D. & Hiddink, J. G., Dec 2018, In : Methods in Ecology and Evolution. 9, 12, p. 2362-2371

    Research output: Contribution to journalArticle

Related by journal

  1. Integrating aerial and ship surveys of marine birds into a combined density surface model: a case study of wintering Common Loons

    Winiarski, K., Burt, M. L., Rexstad, E., Miller, D. L., Trocki, C., Paton, P. & McWilliams, S., 2014, In : Condor. 116, 2, p. 149-161

    Research output: Contribution to journalArticle

  2. Black-capped Chickadees select spotted knapweed seedheads with high densities of gall fly larvae

    Templeton, C. N., May 2011, In : Condor. 113, 2, p. 395-399 5 p.

    Research output: Contribution to journalArticle

  3. Breeding strategies of a socially monogamous neotropical passerine: extra-pair fertilizations, behavior and morphology.

    Carvalho, CBV., Macedo, RH. & Graves, J. A., Aug 2006, In : Condor. 108, 2, p. 579-590 12 p.

    Research output: Contribution to journalArticle

  4. Large-scale movements and habitat characteristics of king eiders throughout the nonbreeding period

    Phillips, L. M., Powell, A. N. & Rexstad, E. A., Nov 2006, In : Condor. 108, 4, p. 887-900 14 p.

    Research output: Contribution to journalArticle

ID: 5285890