NatureScot Commissioned Report 897: Population viability analysis of the Sula Sgeir gannet population

SNH Commissioned Report 897 front cover

NatureScot licenses the annual harvest of gugas – young, pre-fledged northern gannets – on Sula Sgeir.

A population viability analysis of the island’s gannet population was carried out in light of concerns about its sustainability at the current level of licensed harvesting. The aim was to work out the size at which the annual harvest would adversely affect the long-term viability of the breeding population.

To assess the impact of varying levels of harvest, the model used:

  • known estimates of demographic parameters – i.e. breeding success, survival of different age classes
  • an estimate of immigration

The analysis shows that the current level of harvest is unlikely to affect the long-term sustainability of the Sula Sgeir northern gannet population.

Published: 2016
Pages: 27

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Publication 2016 - NatureScot Commissioned Report 897 - Population viability analysis of the Sula Sgeir gannet population

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