Dragonflies and Damselflies

Eighty-one dragonflies and damselflies are known to occur in Germany, and two of them are listed as extinct. Only 7 of the 81 species were recognized in this study as relict species (cf. Sternberg 1998). Coenagrion hylas is extinct in

Table 5 Relict dragonflies and damselflies species in Germany listed in the Habitats Directive

Species

Habitats

Conservation Status (National Report Art. 17, Hab.

Directive

Dir.; Nationaler Bericht 2007)

Biogeographic region

Annex

Atlantic

Continental

Alpine

Damselfly, Coenagrion hylas

II

Extinct in Germany

Siberian Winter

IV

Unfavourable - bad

Unfavourable -

Unknown

Damselfly, Sympecma paedisca

inadequate

Germany (one of the two extinct species in Germany), and five of the remaining six species are specialists of dystrophic habitats. Two species are listed in the Annexes of the Habitats Directive (Table 5). Most of the breeding habitats of these five species (Nehalennia speciosa, Aeshna caerulea, A. subarctica, Somatochlora alpestris, S. arctica) belong to the following habitat types of the Habitats Directive:

• 7110 active raised bogs

• 7120 degraded raised bogs still capable of natural regeneration

• 7140 transition mires and quaking bogs

• 3160 natural dystrophic lakes and ponds.

Although many of the populations and habitats of the relict species are protected by the network of Natura 2000, their conservation status is not good. The main reason is the unfavourable conservation status of their habitat types. In the Atlantic and the Continental biogeographic regions, all four habitat types are considered to have an unfavourable conservation status. Only in the Alpine biogeographic region is the conservation status mostly favourable. The essential threats to these low-nutrient habitats are the intake of nutrients and the exposure level of air pollutants (even by air), the lowering of ground water levels and recultivation of bogs. As a result, the typical poor nutrient water ecosystems and the water chemistry have to be safeguarded, and buffer zones should be created to minimize the inflow of nutrients from surrounding surfaces. The damselfly Sympecma paedisca is endangered in Europe and strongly protected by the EU Habitats Directive Annex IV. It is a relict with a Continental distribution. Beneath moorland habitats such as dystrophic waters more nutrient-rich standing waters were also colonized. Although there are no sites especially protected by the Habitats Directive for this species, many of the populations are found in protected areas in Germany. The conservation status of the species in the Atlantic and Continental region is unfavourable - bad and unfavourable - inadequate, respecitvely, and is unknown in the Alpine region. The number of populations of S. paedisca in Germany is decreasing severely, at least in Lower Saxony and Baden-Württemberg. Besides habitat degradation, climate change could also be one of the reasons for the decline (Ellwanger and Mauersberger 2003).

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