The ferreret, the management of a critically ill species


This study is summarised as evidence for the following.

Action Category

Remove or control viperine snakes

Action Link
Amphibian Conservation

Release captive-bred Mallorcan midwife toads

Action Link
Amphibian Conservation
  1. Remove or control viperine snakes

    A before-and-after study in 1991–2002 of Mallorcan midwife toads Alytes muletensis in Mallorca (Román 2003) found that abundance increased at one of two sites after removal of viperine snakes Natrix maura. At the site with intensive control over three years, no snakes were seen from 1997 and larval toad counts increased from 1,300 in 1991 to 2,200 in 1999. Control was not considered successful by the authors at the second site due to the large snake population and more open habitat. Viperine snakes were controlled by capturing intensive one site in 1991–1993 and by capturing less intensively at the second site in 2002.


  2. Release captive-bred Mallorcan midwife toads

    A before-and-after study in 1985–2002 in Mallorca (Román 2003) found that captive-bred Mallorcan midwife toads Alytes muletensis released as larvae and adults established breeding populations at 12 of 15 sites. Between four and 721 larvae were counted per site in 2001 and 4,000–5,000 were counted at one site in 2002. Two of the three populations failed because of predation by viperine snakes Natrix maura. From 1985, captive breeding was undertaken by a number of national and international centres. Adults (0–387/site) and larvae (0–227) were released at 15 sites over one to nine years in 1985–1997. Populations were surveyed in 2001.


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