Ecological barriers shaping fuel stores in barn swallows Hirundo rustica following the central and western Mediterranean flyways.

Analyzes whether the distance to be covered across ecological barriers can be considered as a factor affecting pre-migratory fuel stores in barn swallows. Energy stores during the post-breeding phase at roost sites in Italy and Spain; Correlation between the wide of ecological barriers and an average index of energy stores for each roost site; Population-specific variability of fuel stores.