De Bosbeekjuffer (Calopteryx virgo) in de omgeving van Winterswijk Heeft een zeldzame beeksoort geprofiteerd van herstelmaatregelen?

This article describes the population trends of Calopteryx virgo in several streams in the Winterswijk area (Gelderland), in the Eastern part of the Netherlands. From the mid 1970s a strong decline of the species was observed. The decrease can be attributed to decreasing water quality. Since the mid 1990s the species has recovered and has recolonised its historic distribution area. The increase can be attributed to several restoration measures, improving the ecological quality of the streams. These measures focused both on water quality and stream morphology.