Nest Density of the Black-headed Gull in Relation to Vegetation

Black-headed Gulls at Ravenglass (Cumbria) show a marked preference for nesting in the cover of marram, which is however replaced by nettles after several years of fertilisation of the dunes by the birds' guano. The marram recovers some years after desertion of nettle areas, and shifts within the gullery are always from nettle-grown to new marram sites.