Polar Biology

, Volume 27, Issue 5, pp 304–311

Examining natural population growth from near extinction: the case of the Antarctic fur seal at the South Shetlands, Antarctica

  • R. Hucke-Gaete
  • L. P. Osman
  • C. A. Moreno
  • D. Torres
Original Paper

DOI: 10.1007/s00300-003-0587-8

Cite this article as:
Hucke-Gaete, R., Osman, L.P., Moreno, C.A. et al. Polar Biol (2004) 27: 304. doi:10.1007/s00300-003-0587-8

Abstract

This study examined the recovery process of an Antarctic fur-seal population, starting from minimal numbers after commercial exploitation to the now largest breeding population in the South Shetland Archipelago, Cape Shirreff and San Telmo Islets. It used direct census data from 20 breeding seasons (including 11 consecutive years) that spanned over 45 years. Since early population estimates, pup production increased at an intrinsic rate of ca. 20% which, during the last decade, dramatically slowed to 4.6%. The population-change trajectory is currently converging into a tightly bounded oscillation around an apparent equilibrium (carrying capacity), which is an order of magnitude lower than those levels before exploitation began. This pattern suggests the onset of an alternative stable state and highlights the far-reaching implications of strong and large-scale perturbations on marine systems.

Keywords

Arctocephalus gazellaPopulation recoveryTime seriesMonitoringExploitationCarrying capacity

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • R. Hucke-Gaete
    • 1
  • L. P. Osman
    • 1
  • C. A. Moreno
    • 1
  • D. Torres
    • 2
  1. 1.Instituto de Ecología y EvoluciónUniversidad Austral de ChileValdiviaChile
  2. 2.Instituto Antártico ChilenoSantiagoChile