The Need of Evidence-Based Management: the Case of the of the Lesser White-Fronted Goose in Northern Norway

an overall positive effect of management. However, in Arctic ecosystems, factors such cyclic small rodent populations and fluctuations in ungulate carrion availability can determine strong variation in annual predation pressure and in turn affect geese recruitment and survival. Using 19 years of data, we investigated to what extent red fox culling contributed to the recovery of the population. Specifically, we evaluated whether fox removal had the expected positive effect on LWFG reproductive success, while taking into account those factors outlined above that may confound the effect of the management action. We predicted LWFG breeding success to fluctuate synchronously with the rodent cycle due to an apparent facilitation mechanism. We also expect that increased availability of reindeer carcasses sustain foxes during the harsh arctic winter and enhance their survival, especially in years with deep snow that makes small rodents less accessible. Thus, we predicted lower reproductive success in years with high carcass abundance, due to an apparent competition mechanism. Moreover, we used these relationships to assess the relative impact of fox culling program. We found a strong positive effect of rodent density on geese breeding success, as well as a negative effect of the yearly amount of reindeer carcasses. However, there was no evidence in the data for any positive effect of fox culling. These results are relevant for the conservation of the LWFG population. Overall, this study emphasize the importance of scientifically evaluating the effectiveness of management actions by taking into account all the potential confounding factors.