Butterfly and Moth Welfare and Habitat

Butterfly and moth populations have declined dramatically in the UK, with habitat loss, pesticide use and climate change creating welfare challenges for billions of individual insects that depend on specific food plants and conditions.

Key Facts

Three quarters of UK butterfly species have declined in abundance or distribution since the 1970s
Moths have declined by 33% in abundance in Britain since 1968, with larger declines in southern England
Caterpillars of specialist species are completely dependent on specific food plants — loss of food plants means starvation and death
Light pollution disrupts moth navigation, feeding, mating and migration, causing disorientation and death
The UK Butterfly Monitoring Scheme has documented butterfly population trends since 1976 using transect walks

Welfare Considerations

The welfare implications of butterfly and moth decline are significant even under considerable uncertainty about the richness of insect experience. Caterpillars that starve because their food plant has been eliminated from the landscape, moths that circle light sources until exhaustion, and butterflies that cannot complete migration due to habitat gaps all face conditions that, if experienced, would constitute suffering. The precautionary principle suggests that the mass death and deprivation of food, shelter and mate access experienced by declining insect populations deserves moral attention even before the question of insect sentience is fully resolved.

What You Can Do

Plant butterfly and moth food plants specific to your region including nettles, bird foot trefoil and wild marjoram
Reduce or eliminate light pollution from your property to protect nocturnal moths
Participate in Big Butterfly Count and moth recording schemes at www.butterfly-conservation.org
Create diverse wildflower habitat in your garden or green space to support caterpillar food plants
Advocate for pesticide reduction and pesticide-free zones around key butterfly and moth sites