Individual study: Re-introduction of the fire-bellied toad Bombina bombina in Southern Sweden
Andren C. & Nilson G. (1995) Re-introduction of the fire-bellied toad Bombina bombina in Southern Sweden. Memoranda Societatis pro Fauna et Flora Fennica, 71, 82-83
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Release captive-bred toads
A replicated, before-and-after study in 1982–1993 in Sweden (Andren & Nilson 1995) found that released captive-bred fire-bellied toad Bombina bombina metamorphs established populations at seven of 10 sites, with some populations increasing over three years. By 1993, toads were found in 75 ponds. Numbers of ponds with calling males decreased from 26 in 1990 to 15 in 1993, although numbers calling increased to 80. Metamorphs were recorded at 0–10 ponds. The total minimum population size varied from 150 to 300. In 1982–1984, eggs from Denmark were raised to adults for breeding. Over six years, captive-bred larvae were released into net cages in ponds at 10 sites, each with 2–15 suitable breeding ponds. Some eggs were raised to metamorphs before release, all metamorphs were set free in ponds. Toads were monitored in 1990–1993.