De toename van de Vuurjuffer (Pyrrhosoma nymphula) in het westen van Noord-Holland

Pyrrhosoma nymphula is a very common dragonfly in the east and south of The Netherlands, but until 1998 the species was largely absent in the west. The species has been present in the coastal dunes in the south of North Holland Province since the early 1990s. Pyrrhosoma nymphula has shown a strong increase in this area, and appears still to be expanding. The species appeared further north in North Holland in 1999, and has increased ever since, occurring in the dunes and also in garden ponds. In the spring of 2001 a regional campaign has held to assess the distribution of Pyrrhosoma nymphula in the north of North Holland, adding many new records. It is difficult to say how Pyrrhosoma nymphula reached the area. Perhaps it expanded from the south, aided by wind and using garden ponds as stepping stones. However it may be, Pyrrhosoma nymphula has in three years become common in the north of North Holland. Further south, along the coast of South Holland and Zeeland provinces Pyrrhosoma nymphula seems to be less abundant, although records are increasing. It will be interesting to see whether Pyrrhosoma nymphula will remain present along the Dutch coast and whether she will expand further.