Dijkstra, K.-D.B., K. Mostert, J.-W. van Velzen & R.H. Witte, 1988. Recent developments in the dragonfly fauna of the dunes of Holland and Zeeland. Brachytron 3(1): 15-29. The coastal dunes are isolated from the species-rich habitats on sandy soils inland by a belt of relatively inhospitable polders with peaty and clay soils. They also form an almost unbroken natural corridor through which dragonfly migration is possible, whilst the sea is a barrier that forces migrants from the east to settle. Remarkable invasions, colonizations and vagrancies by Odonata during the last five years along the Dutch coast, excluding the Wadden Sea islands, are listed. There were large invasions of Lestes barbarus, Aeshna affinis, Sympetrum danae, S. flaveolum and S. fonscolombii, all of which reproduced in the area subsequently. Sympecma fusca, Lestes dryas, Ischnura pumilio, Pyrrhosoma nymphula, Brachytron pratense, Aeshna isosceles, Libellula depressa, Crocothemis erythraea and Leucorrhinia rubicunda bred successfully. All of these species were either new in this sense, or had been absent for many years. Calopteryx splendens, Lestes virens, Hemianax ephippiger, Gomphus vulgatissimus, Somatochlora metallica and Leucorrhinia pectoralis reached the region as vagrants, thus proving they are capable of reaching new habitats when these are created. Habitat restoration, increasing observation intensity, prevailing weather and expanding ranges are discussed as factors to explain the new records. Most of the treated species appear to have reached the area with the help of easterly winds and fine weather. Habitat restoration has principally created opportunities for pioneer species and those adapted to fluctuating water levels. It is suggested that permanent, mesotrophic lakes should be restored in order to bring back species that are extinct in the dunes, like Cordulia aenea and L. pectoralis.

, , , , , , , ,
Brachytron

CC BY 3.0 NL ("Naamsvermelding")

Nederlandse Vereniging voor Libellenstudie

Klaas-Douwe B. Dijkstra, Kees Mostert, Jan-Willem Van Velzen, & Richard H. Witte. (1999). Recente ontwikkelingen in de libellenfauna van de Hollandse en Zeeuwse duinen. Brachytron, 3(1), 15–29.