Data from: Assessing the effect of predator control on an endangered goose population subjected to predator-mediated food web dynamics

1. Assessing the effectiveness of conservation actions to halt population
declines is challenging when confounded by other factors. We assessed
whether culling of red fox, a predator currently increasing in the
sub-Arctic, contributed to recent recovery of the critically endangered
Fennoscandian population of Lesser White-fronted Goose Anser erythropus,
while controlling for potentially confounding food web dynamics. 2. Using
19 years of data, 10 before and 9 after the implementation of annual red
fox culling, we estimated the effect of this action on annual performance
of the goose population. We corrected for the potentially confounding
effects of cyclic rodent dynamics and semi-domestic reindeer carrion
abundance, both of which are expected to trigger predator functional and
numerical responses, as well as for annual variation in spring phenology.
3. Goose reproductive success fluctuated in synchrony with the rodent
cycle and was negatively related to abundant carrion. When accounting for
these aspects of food web dynamics, there was no evidence for an effect of
red fox culling on reproductive success. There was, however, a tendency
for fox culling to increase adult survival. 4. Our analysis suggests that
goose performance in their breeding area is influenced by fluctuating
offspring predation, mediated by mainly natural (rodents) and partly
anthropogenic (semi-domestic reindeer) dynamic components of the food web.
5. Synthesis and applications. The effect of a decade-long red fox culling
on goose reproductive success and survival is currently uncertain. This is
despite the fact that predation drives reproductive success through
changes in rodent and reindeer carrion abundance. New management actions
may consist of regulation of reindeer herd sizes and/or removal of
carcasses to reduce the subsidizing effect of reindeer carrion on
mesopredators. Getting robust evidence regarding the impact of red fox
culling on population recovery depends on continuing research to
disentangle food web dynamics and efficiency of management actions.