The natural range of the yellow-bellied toad in the Netherlands is restricted to the southernmost part of the province of Limburg, east of the river Meuse. It was quite common until the 1960s, when the species was found in 80 ponds. Nowadays the yellow-bellied toad is present in the marl quarries ‘Groeve ’t Rooth’ and ‘Julianagroeve’ and at Gerendal, Berghofweide and Wahlwiller (an introduction using animals from Groeve ’t Rooth). There are some occasional observations around these populations. In 2005 yellow-bellied toads were introduced in the marl quarry ‘Groeve Blom’ and in 2006 in the gravel quarry ‘Meertensgroeve’. The total Dutch population centres around 100 and 350 (sub)adults.
The yellow-bellied toad is listed on the Red List as critically endangered. It is strictly protected under Dutch legislation, the Bern Convention (Annex ii) and the Habitats Directive (Annex ii and iv). The range of the yellow-bellied toad decreased by 79% since 1950. Main causes of decline are intensification and increased extent of agricultural practices. Many ponds, steep-sided embankments, shrubberies, unmanaged farm yards and other extensively used areas of land have disappeared or have been tidied up. Lowering of the water levels also played a major role. Pioneer waters on road tracks, in marl quarries and around villages became less and less common. This process started in the 1950s. Quarries have long been important substitutes, and still are, but are less used and therefore suffer from vegetation succession. Animals have been caught for pet trade. There is much experience concerning habitat management, especially of water habitats, in the Netherlands. Only extremely pioneer water types (temporary shallow ponds) seem to function as breeding waters. Due to intensive management numbers are growing in recent years, but the yellow-bellied toad definitely remains the most critically endangered amphibian in the Netherlands.
Laan, R.M., Delft, J.J.C.W. van, Bosman, W.
- Creemers, R.C.M. & J.J.C.W. van Delft 2009. De amfibieën en reptielen van Nederland 9. Nationaal Natuurhistorisch Museum Naturalis, KNNV Uitgeverij & European Invertebrate Survey-Nederland, Leiden.