Differences in the time budget of the Greater White-fronted Goose (Anser albifrons) in grasslands and arable fields at an important spring stopover site in central Europe

Abstract

Changes in the management and productivity of farmland affect foraging behaviour in migrating birds. Crops are increasingly being damaged (and farmers are sustaining ever greater economic losses) as a result of large flocks of waterfowl feeding on them. To investigate the differences in the time budget shared between natural grasslands and arable lands, migrating Greater White-fronted Geese (Anser albifrons) were filmed using digiscoping equipment at a spring stopover site. Four types of activity were noted in connection with habitat types, bird age, position in the flock and flock size. Foraging was the most common activity in both habitats, but was more common in the grasslands than on arable land. The mean times spent on vigilance, resting and other activities were also significantly different between the two habitat types. GLM analysis showed that young birds spent more time foraging than adults but revealed no differences in foraging times between the age categories in grasslands and arable land. In the latter, geese were more vigilant at the edge of a flock and rested more frequently in its centre. No such differences were found in the grasslands. Only resting time was adversely affected by flock size. These findings, which demonstrate that White-fronted Geese are flexible in their use of food resources, could be useful in agricultural management planning in the light of increasing conflicts with farmers.