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USGS · 70175576

Adaptive harvest management for the Svalbard population of pink‐footed geese: 2016 progress summary: Technical Report from DCE – Danish Centre for Environment and Energy, No. 86

Fred A. Johnson·Jesper Madsen
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Abstract

This document describes progress to date on the development of an adaptive harvest management strategy for maintaining the Svalbard population of pink‐footed geese (Anser brachyrhynchus) near their agreed target level (60,000) by providing for sustainable harvests in Norway and Denmark. This report provides an assessment of the most recent monitoring information (1991-2015) and its implications for the harvest management strategy. By combining varying hypotheses about survival and reproduction, a suite of nine models have been developed that represent a wide range of possibilities concerning the extent to which demographic rates are density dependent or independent. These results suggest that the pink‐footed goose population may have recently experienced a release from density‐dependent mechanisms, corresponding to the period of most rapid growth in population size. Beginning with the 2016 hunting season, harvest quotas will be prescribed on an annual basis rather than every three years because of the potential to better meet population management objectives. Based on updated model weights, the recent observations of population size (74,800), the proportion of the population comprised of one-year-old birds (0.138), and temperature days in Svalbard (20), the optimal harvest quota for the 2016 hunting season is 25,000. The large increase in quota compared to that during first three years of AHM reflects stakeholders’ desire to reduce population size to the goal of 60,000, recognizing that population size remains relatively high and above-average production is expected in 2016 due to a warm spring.

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Fred A. Johnson, Jesper Madsen. 2016. Adaptive harvest management for the Svalbard population of pink‐footed geese: 2016 progress summary: Technical Report from DCE – Danish Centre for Environment and Energy, No. 86. https://pubs.usgs.gov/publication/70175576

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