Journal Article

A refined fish consumption model for lactating Cape fur seals (<i>Arctocephalus pusillus pusillus</i>), based on scat analyses

Silvia Mecenero, Stephen P. Kirkman and Jean-Paul Roux

in ICES Journal of Marine Science

Published on behalf of ICES/CIEM

Volume 63, issue 8, pages 1551-1566
Published in print January 2006 | ISSN: 1054-3139
Published online January 2006 | e-ISSN: 1095-9289 | DOI: http://dx.doi.org/10.1016/j.icesjms.2006.06.005
A refined fish consumption model for lactating Cape fur seals (Arctocephalus pusillus pusillus), based on scat analyses

More Like This

Show all results sharing these subjects:

  • Environmental Science
  • Marine and Estuarine Biology

GO

Show Summary Details

Preview

A refined fish consumption model for lactating Cape fur seals in Namibia during the eight-month lactation period, which allows for spatio-temporal variation in the diet as determined by scat analyses, has been developed. Previous estimates of prey consumption by Cape fur seals have been based mostly on coarse diet composition models. Sensitivity analyses showed that the energetic requirement and mass of lactating females (bioenergetic variables), as well as the energetic density of prey (diet variable), contributed most to the uncertainty in consumption estimates. Uncertainty in the remaining input variables had minimal effects on the estimates of food consumption. The consumption of commercial prey (horse mackerel, hake and pelagic fish) was greatest by the colony at Cape Cross. The model estimated that a female of average mass 55 kg ingested, on average, 11% of her body mass per day. This model is easily applied to other age/sex classes of the seal population. It permits improvement of the estimates of prey consumption by seals, which are useful for assessing levels of competitive interactions between seals and fisheries or other predators, or the impacts of seals on prey species.

Keywords: Cape fur seal; fish consumption; lactating females; model; Namibia; scat analysis; spatial variation; temporal variation

Journal Article.  10436 words.  Illustrated.

Subjects: Environmental Science ; Marine and Estuarine Biology

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.