Study

Recovery of the green toad Bufo viridis Laurenti, 1768 on coastal meadows and small islands in Funen County, Denmark

  • Published source details Briggs L. (2003) Recovery of the green toad Bufo viridis Laurenti, 1768 on coastal meadows and small islands in Funen County, Denmark. Deutsche Gesellschaft für Herpetologie und Terrarienkunde, 14, 274-282

Actions

This study is summarised as evidence for the following.

Action Category

Create ponds for green toads

Action Link
Amphibian Conservation

Manage grazing regime

Action Link
Amphibian Conservation

Translocate toads

Action Link
Amphibian Conservation

Restore ponds

Action Link
Amphibian Conservation
  1. Create ponds for green toads

    A before-and-after study in 1989–1997 of 23 created and 25 restored ponds within coastal meadows on nine islands in Funen County, Denmark (Briggs 2003) found that pond creation and restoration, along with terrestrial habitat management, significantly increased a green toad Bufo viridis population. Overall, the population on the islands increased from 1,112 to 3,520 toads over the seven years. Numbers were similar on islands with just pond creation and restoration (1,020 to 952) and increased on the two where cattle grazing was also reintroduced (92 to 2,568). Overall, pond occupancy increased from 23 to 51 and the number of ponds with successful breeding increased from nine to 15. In 1989–1997, ponds were created or restored by removing plants and dredging. Cattle grazing was reintroduced to 73 ha of coastal meadows and abandoned fields on two islands. Populations were monitored annually in 1990–1997 during 2–3 call and visual surveys and dip-netting surveys. One population was also monitored in 1987–1989.

     

  2. Manage grazing regime

    A replicated, before-and-after study in 1989–1997 of coastal meadows and abandoned fields on two islands in Funen County, Denmark (Briggs 2003) found that the green toad Bufo viridis population increased significantly following reintroduction of grazing to fields, along with pond creation and restoration. The population increased from 92 to 2,568. Pond occupancy increased from 10 to 29 ponds and ponds with successful breeding from four to seven. In 1989–1997, cattle grazing was reintroduced to 48 ha of coastal meadows and abandoned fields. Four ponds were created and eight restored by removing plants and dredging. Populations were monitored annually in 1990–1997 during two or three call, visual and dip-net surveys. One population was also monitored in 1987–1989.

     

  3. Translocate toads

    A before-and-after study in 1986–1997 of five ponds on coastal meadows on Avernako island, Denmark (Briggs 2003, Briggs 2004) found that there was a significant increase in green toad Bufo viridis population following translocation of eggs, along with pond creation and restoration and reintroduction of grazing. The population increased from 20 in 1988–1990 to 920 in 1995–1997. Pond occupancy increased from one to seven and the number of ponds with breeding success increased from zero to five. In 1989–1997, one pond was created and four restored by removing plants and dredging. Cattle grazing was reintroduced to 25 ha of coastal meadows and abandoned fields. In 1994–1995, a total of 14,500 eggs were translocated to four of the ponds. Populations were monitored annually in 1990–1997 during two or three call and visual surveys and dip-net surveys.

     

  4. Restore ponds

    A replicated, before-and-after study in 1989–1997 of 25 restored and 23 created ponds on nine islands in Funen County, Denmark (Briggs 2003) found that there was a significant increase in the green toad Bufo viridis population. Overall, the population on the islands increased from 1,112 to 3,520 toads over the seven years. Numbers were similar on islands with just pond creation and restoration (1,020 to 952) and increased on the two where cattle grazing was also reintroduced (92 to 2,568). Overall, pond occupancy increased from 23 to 51 and the number of ponds with breeding success increased from nine to 15. In 1989–1997, ponds were created or restored by removing plants and dredging. On two of the islands, cattle grazing was also reintroduced to 73 ha of coastal meadows and abandoned fields. Populations were monitored annually in 1990–1997 during two or three call and visual surveys and dip-netting surveys. One population was also monitored in 1987–1989.

     

Output references

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