Skip to content

Research at St Andrews

Estimating Annual Pup Production in Grey Seal Breeding Colonies

Research output: Book/ReportCommissioned report


Jason Matthiopoulos, John Harwood

School/Research organisations


Estimating pup production from aerial survey data is the best way of estimating grey seal population size. We have developed a parsimonious model to describe fecundity, pup mortality and loss, pup moulting and departure during the breeding season. To deal with possible misclassification we combined this with a model of the observation process. We have Monte-Carlo Markov-Chain techniques to fit both models. This computer-intensive approach affords considerable flexibility and future expandability to the process model, enables us to support the model with independent information on its parameters in the form of priors, get feedback by directly estimating these parameters in the form of posteriors, and explicitly deal with uncertainty in parameters and predictions. We present preliminary results from an application of this approach to simulated data. This validation exercise demonstrates that despite containing 30 parameters, the model can be fitted successfully to relatively sparse data. The results quantify pup production and provide insights about the demographic processes taking place during the breeding season. We discuss extentions of this methodology and its application to real data from grey seals and other seal species.


Original languageEnglish
PublisherUnknown Publisher
Publication statusPublished - 2003

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

View graph of relations

Related by author

  1. Bio-energetic modeling of medium-sized cetaceans shows high sensitivity to disturbance in seasons of low resource supply

    Hin, V., Harwood, J. & de Roos, A. M., 13 Apr 2019, (Accepted/In press) In : Ecological Applications. In press, e01903.

    Research output: Contribution to journalArticle

  2. Understanding the population consequences of disturbance

    Pirotta, E., Booth, C. G., Costa, D. P., Fleishman, E., Kraus, S. D., Lusseau, D., Moretti, D., New, L. F., Schick, R. S., Schwarz, L. K., Simmons, S. E., Thomas, L., Tyack, P. L., Weise, M. J., Wells, R. S. & Harwood, J., 12 Sep 2018, In : Ecology and Evolution. Early View, 13 p.

    Research output: Contribution to journalReview article

  3. A simulation approach to assessing environmental risk of sound exposure to marine mammals

    Donovan, C. R., Harris, C. M., Milazzo, L., Harwood, J., Marshall, L. & Williams, R., Apr 2017, In : Ecology and Evolution. 7, 7, p. 2101-2111 11 p.

    Research output: Contribution to journalArticle

  4. Approaches to Understanding the Cumulative Effects of Stressors on Marine Mammals

    Tyack, P. L., Bailey, H., Crocker, D., Estes, J. E., Francis, C. D., Harwood, J., Schwacke, L., Thomas, L. J. & Wartzok, D., 2017, Washington DC: National Academies Press. 146 p.

    Research output: Book/ReportCommissioned report

  5. Monitoring population-level responses of marine mammals to human activities

    Fleishman, E., Costa, D. P., Harwood, J., Kraus, S., Moretti, D., New, L. F., Schick, R. S., Schwarz, L. K., Simmons, S. E., Thomas, L. & Wells, R. S., Jul 2016, In : Marine Mammal Science. 32, 3, p. 1004-1021

    Research output: Contribution to journalArticle

ID: 453917