The grasshopper warbler is a secretive migratory songbird whose UK population has declined over 50% since the 1980s due to habitat loss on breeding and wintering grounds.
Grasshopper warblers returning from sub-Saharan Africa face declining suitable breeding habitat in the UK. Drainage of wetlands and improved grassland management removes the tussocky, rank vegetation they need for nesting and foraging. In poor habitat, breeding productivity is low and adults expend greater energy searching for nesting sites and invertebrate prey. Climate change is altering the phenology of their insect food base in ways that may cause mismatch with chick rearing requirements.