EDGE Community


Project information

[Project name/title]
Predicting distribution and climatic differentiation between Alytes dickhilleni and Salamandra salamandra longirostris


[Project description/overview]
This project aims to identify which environmental and climatic factors are the main predictors for the presence of these species.


Location:
Andalucía, Spain.

Project type:
Scientific research

Relevant EDGE species:
Betic midwife toad (Alytes dickhilleni)

Project members:
Wouter Beukema




Relevant species
56. Betic midwife toad (Alytes dickhilleni) VU

Males carry the eggs wrapped around their hind legs and care for them until hatching.

[Relevance description]
Aims
Predicting the distribution of Alytes dickhilleni and Salamandra salamandra longirostris using environmental and climatologically variables; identify the main predictors for the presence of both species; identify a possible climatological difference separating the two species; investigating the degree of isolation within the subpopulations of Alytes dickhilleni.
 
Project summary
Two amphibians are endemics of the Betic mountains in southern Spain (Andalucía); Salamandra salamandra longirostris in the lower, western part and Alytes dickhilleni in the higher eastern mountains. During this project the distribution and its main predictors will be determined using ecological modelling, a GIS-based technique implemented with Maxent. In favour of their conservation the amount of suitable habitat, degree of isolation (especially for A. dickhilleni) and possible migration of the two species into each others distribution will be investigated.
 
Achievements
The results gained during the research period show interesting differences between both species. The main predictor for the distribution of Salamandra salamandra longirostris identified by Maxent is rainfall in January. Actually, the distribution of this subspecies is predicted the most successfully when using only this parameter. Further, temperatures exceeding 30ºC in August have a negative impact on S. s. longirostris.

Contrary to S. s. longirostris, the main predictor for the distribution of Alytes dickhilleni is most influenced by spring and fall rains, but most by the minimum temperature in September, a yet to be clarified parameter. The distribution of this species is clearly isolated in nine Andalucían subpopulations. Interestingly, these populations all correspond to genetic lineages identified in 1992 by Mario Gárcia-Páris.

Figure Below: Predicted distribution (red) of Alytes dickhilleni in Andalucía separated by unsuitable terrain using the threshold produced by the model. Polygons represent isolated subpopulations within the region.
 
Timescales
Start date: 21 July 2008
Duration: Until early 2009
Project members
Wouter Beukema : Researcher

Wouter is an undergraduate student studying amphibians.

[Member role description]
Other key species
Los Barrios Fire Salamander (Salamandra salamandra longirostris)
 
[Title:] Betic Midwife Toad
[Image caption]
Alytes dickhilleni
[Title:] Study Site
[Image caption]
Andalucía, Spain
[Title:] Project Member
[Image caption]
Wouter
[Title:] Betic Midwife Toad
[Image caption]
Alytes dickhilleni