Journal of Marine Sciences / 2011 / Article / Tab 2

Research Article

An Approximate Bayesian Method Applied to Estimating the Trajectories of Four British Grey Seal (Halichoerus grypus) Populations from Pup Counts

Table 2

Estimates (mean and 95% credibility intervals) of the total size of the grey seal populations in each region before breeding in 2007. The results for the two models are given along with those from simple (equally weighted) model averaging and applying the uniform prior across the two models. The numbers in italics are the equivalent estimates calculated from the best fitting state space models contained in the 2008 report of the UK Standing committee on Seals [18].

Model2007 Regional Population (in thousands, mean value, and 95% CIs1)
North SeaOrkneyInner HebridesOuter HebridesTotal2

Density dependent pup survival20.9 (16.4–25.7)46.1 (35.6–58.0)8.0 (5.9–10.7)34.3 (27.0–42.0)109.4 (84.8–136.4)
17.1 (10.6–25.9)60.9 (40.9–93.5)8.3 (6.5–10.5)31.3 (24.0–39.1)117.6 (89.1–168.9)

Density dependent fecundity24.1 (19.7–29.0)124.6 (102.2–151.1)24.7 (18.3–34.2)69.6 (57.0–86.0)243.3 (190.8–277.9)
27.2 (20.7–38.2)103.0 (79.5–142.9)21.4 (16.5–32.1)88.1 (67.0–143.0)239.7 (188.8–356.2)

Model averaged22.5 (17.1–28.3)85.4 (37.2–146.2)16.4 (6.2–32.3)52.1 (28.1–82.5)177.3 (88.5–289.2)
20.5 (11.1–33.6)75.4(40.4–130.0)12.9 (6.5–27.2)51.2 (23.8–111.5)160.1 (84.5–304.5)

Uniform prior22.5 (18.0–27.3) 85.78 (45.8–131.3)16.3 (8.0–27.7)52.1 (33.1–74.3)176.8 (104.6–260.8)

1All the CIs include uncertainty in the population sex-ratio.
2The CIs are estimated conservatively by summing those of the individual models.

We are committed to sharing findings related to COVID-19 as quickly and safely as possible. Any author submitting a COVID-19 paper should notify us at to ensure their research is fast-tracked and made available on a preprint server as soon as possible. We will be providing unlimited waivers of publication charges for accepted articles related to COVID-19. Sign up here as a reviewer to help fast-track new submissions.