Ecology Letters (2010) 13: 597–605 Abstract Intensification or abandonment of agricultural land use has led to a severe decline of semi‐natural habitats across Europe. This can cause immediate loss of species but also time‐delayed extinctions, known as the extinction debt. In a pan‐European study of 147 fragmented grassland remnants, we found differences in the extinction debt of species from different trophic levels. Present‐day species richness of long‐lived vascular plant specialists was better explained by past than current landscape patterns, indicating an extinction debt. In contrast, short‐lived butterfly specialists showed no evidence for an extinction debt at a time scale of c. 40 years. Our results indicate that management strategies maintaining the status quo of fragmented habitats are insufficient, as time‐delayed extinctions and associated co‐extinctions will lead to further biodiversity loss in the future.

Habitat fragmentation causes immediate and time‐delayed biodiversity loss at different trophic levels