Colony habitat selection by Little Terns Sternula albifrons in East Anglia: implications for coastal management

Abstract

Little Terns Sternula albifrons are unusual among UK seabirds in that a large proportion of the population breed on mainland beaches in East Anglia. Relative sea-level rise means that such habitats are under threat in this region, and so we quantified colony habitat selection of beach nesting Little Terns in order to inform habitat restoration and creation initiatives. Random 1 km sections of beach were selected and the presence or absence of a Little Tern colony within each was related to physical (substrate type, height and width), biotic (vegetation cover, predator activity) and anthropogenic (disturbance) characteristics using logistic regression models. Little Terns positively selected for beaches with vegetation cover and negatively for those with high disturbance levels. They showed no selection according to width and height or Red Fox Vulpes vulpes presence, even though these are likely to affect flood and predation risk respectively. Red Foxes were found to be widespread on beaches irrespective of tern colony presence, and so movement of tern colonies will not always result in predator avoidance. Little Tern habitat creation needs to be integrated into coastal management plans in order to safeguard their population from the combined threats of relative sea-level rise, predation and disturbance.