Barn Swallow Welfare and Farm Building Conservation

Barn swallows are declining across the UK as traditional farm buildings are renovated, converted or demolished, removing the nest sites that their colonies depend on.

Key Facts

UK barn swallow numbers have declined by approximately 40% since the 1970s, driven by loss of nest sites and invertebrate prey depletion
Swallows nest almost exclusively in accessible farm buildings, requiring open access through spring and summer
Each breeding pair can raise 2-3 broods per season — loss of nest sites has immediate population-level welfare impact
Swallows are long-distance migrants travelling to Sub-Saharan Africa each autumn, facing hazards along the entire flyway

Welfare Considerations

Barn swallow welfare is concentrated in the breeding season, where successful nest site retention determines reproductive output. Conversion of farm buildings to residential use almost invariably destroys swallow colonies through access restriction — even where nests are legally protected, access point blocking eliminates future use. Ghost farms, where livestock have been removed but buildings remain accessible, retain swallow populations. Swift and swallow nest access bricks can be incorporated into building renovations at minimal cost to maintain nesting opportunities.

What You Can Do

Retain access points to farm buildings used by swallows before and during the March-August breeding season
Incorporate access bricks or external nest cups into any building renovation affecting established swallow colonies
Maintain farmland invertebrate populations through reduced pesticide use to support swallow foraging
Report breeding swallows to BTO BirdTrack to contribute to annual population monitoring