Pond restoration on Bornholm


This study is summarised as evidence for the following.

Action Category

Restore ponds

Action Link
Amphibian Conservation
  1. Restore ponds

    A replicated, before-and-after study in 1983–1985 of 23 restored ponds on Borholm, Denmark (Fog 1988) considered that 14 were successful and two failed. European tree frogs Hyla arborea were found in 10 ponds. There were large tree frog population increases in two ponds, moderate increases in five, no change in one and declines in two ponds post-restoration. One of the failures was due to pollution, another to ducks and restoration had changed the community in a third pond. In 1983–1985, 23 ponds were restored on private land, primarily to improve European tree frog populations. Restoration involved activities such as dredging and tree cutting.


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