Critical components in the dynamics of a barnacle goose colony: A sensitivity analysis. Norsk Polarinstitutt Skrifter 200:81 – 89

The considerable increase in arctic goose populations over the last decades has induced large ecological and economical impacts on the environment. When planning how to alleviate some of these problems, environmental managers will need background information on the behaviour and dynamics of arctic goose populations. In this study the demographic parameters which have the strongest effect on population growth are assessed. Sensitivity/elasticity analyses were performed on an eight-year data set of a newly established barnacle goose Branta leucopsis colony in Kongsfjorden, Svalbard. The work included measurement of the sensitivity of the population's growth rate to changes in different demographic parameters and of how relative changes in different demographic parameters influence relative changes in population growth rate (elasticity analysis). An evaluation was made of which demographic parameters were most responsible for the variation in population growth the last eight years. The results from these analyses demonstrated that adult survival rates and late gosling survival were the most important factors determining changes in the colony's growth rate, followed by early gosling and egg survival. Juvenile survival rates had less effect on the population growth rate, whereas clutch size had the least effect. Results from the elasticity analyses showed that a proportional change in adult survival rates will have an impact on the growth rate 2.1 times greater than a proportional change in any of the other demographic parameters measured. During the las