Focus species: Natterjack toad

Epidalea calamita formerly Bufo calamita

Natterjack toad, © Andreas Meyer, karch

The knowledge of various experts was included in the selection of the amphibian species.


  • Characteristics
    • Body 5-7 cm long, females and males similar in size.
    • Short hind legs, locomotion therefore rather mouse-like
    • Upper side of body whitish with olive marbling
    • Dorsal midline clearly yellow (rarely absent)
    • Often red-orange tubercles on upper side
    • Legs more distinctly olive marbled
    • Females darker green-olive coloured
    • Iris yellow-green, pupil horizontal-elliptic
    • Ear glands (parotids) clearly visible, parallel
    • Underside whitish
    • Throat skin of male blue-violet coloured, can be inflated to almost body-size throat bladder
  • Voice
    • Males call with a metallic “ärrr-ärr”.
    • Usually calls directly at the water’s edge
  • Habitat
    • Originally a pioneer species on gravel and sand banks of free-flowing rivers.
    • Puddles left by floods provide ideal conditions for spawning.
    • Today in places where temporary small bodies of water are repeatedly created: Gravel pits, sand and clay pits, quarries, weapons sites, construction sites and landfills.
    • During the day they hide under boards, stone slabs, bricks or in holes in the ground.
  • Breeding
    • The mating season begins in mid-March and lasts until August, peaking at the end of April/May. Males call at dusk, usually standing directly at the water’s edge. If a conspecific is spotted, it is pursued and grabed. Males are also grabed by other males. To get away, they make a defensive sound and defend themselves with their hind legs. When mating with a female, in the best case, after a few hours she lays a one- or two-row spawning line with several thousand eggs, which are inseminated by the male at the same time, in shallow water.
    • Natterjack toads lay their spawn in small temporary bodies of water that can warm up considerably and harbour few enemies. Tadpoles can develop quickly (3-6 weeks) if the water does not dry out prematurely.
  • Distribution
    • Southern Spain, France, Belgium, the Netherlands, Luxembourg, Germany, Denmark, the Czech Republic, Poland, western Russia, England, Ireland.
    • Switzerland: only on the northern side of the Alps at lower altitudes.
    • Relatively common until 10 years ago, currently suffering drastic population decline
Landkarte zur Illustration der Verbreitung der Kreuzkröte
Distribution of the natterjack toad in Switzerland, red: data as of 2000, orange: data before 2000, © info fauna – CCO/KOF, swisstopo
  • Endangerment and conservation measures
    • Red List status (Switzerland): endangered (EN)
    • Rare amphibian species in Switzerland
    • Because its natural habitat, the floodplains, has been destroyed or altered by the lack of natural water dynamics, the species is dependent on man-made pioneer sites such as quarries. However, these are very unstable.
    • Protection of suitable habitats such as pits and quarries
    • Artificial creation of temporary water bodies
    • Planning and creation of entire chains of pioneer habitats that are regularly restored to their initial state
    • Creation of original natterjack toad habitats by restoring river and lake level water dynamics