Alma Amphibia Pond

Amphibians are the most threatened group of vertebrates on the planet, and it is estimated that between 40% and 50% of their species would be included in some category of threat of extinction of the IUCN (Reference 1 and Reference 2). This post is therefore about ponds and amphibians.

Between 1980 and 2004, 91% of the deterioration in the conservation status of amphibians was explained by habitat loss and diseases. Since 2004, 39% of the deterioration of the amphibian situation is explained by the effects of climate change (reference 1). At least 500 amphibian species have seen a marked decline in their populations due to chytridiomycosis, which would probably have also caused the extinction of 90 of these species Reference 3).

Within this sad global scenario, the situation of amphibians in Spain is no exception: wetlands are shrinking and losing more and more wetlands, the presence of American red crab (Procambarus clarkii) makes it impossible for some amphibian species to survive, diseases such as chytridiomycosis (caused by the fungus Batrachochytrium dendrobatidis) give rise to mass deaths (Reference 4), etc.

Being very aware of this situation, at Ideas MedioAmbiental we collaborate with the Alma Amphibia Project with the intention of helping locally to improve the habitat for amphibians in the municipality of Almansa (Albacete).

As part of this collaboration, in November 2022, the construction of an artificial pond was proposed. The initiative was very well received and more than 40 people of different ages, from children to “younger children”, enthusiastically helped to prepare the pond.

Ponds and amphibians

With a pick, shovel, rake... interspersing several layers of PVC and geotextile canvas, accumulating stones, and installing a small hunting mesh fence (which allows the passage of foxes, garduñas, hares, rabbits, squirrels, etc.) together we managed to build the pond in the surroundings of Rambla de Tobarrillas.

The activity, with a clear nature of education and environmental awareness, was completed by encouraging, especially the youngest, to build nest boxes for different nocturnal birds of prey (owl, common owl and owl) and small forest birds as parishes. Some of these boxes were hung around the pond.

Would that small body of water help amphibians in the area? Would wild boars arrive soon and destroy the bottom of the pond? There were diverse opinions, from moderately optimistic to very pessimistic. Willing to find out what would happen, photo-trapping cameras were installed and we also visited the pond periodically.

Overcoming pessimistic forecasts, during the first six months the pond became naturalized little by little, changing the color of its waters to a “eutrophied” green, with the presence of tiny algae and also observing invertebrates such as those of the genus Notonecta who were swimming in the pond.

Predictably, the accumulation of water attracted many birds and some mammals, although we couldn't see a trace of amphibians.

Red squirrel (Sciurus vulgaris) visiting the edge of the pond.

Common Hawk (Accipiter nisus) perched next to the pond.

And so May 2023 arrived, with the pond maintaining a fairly “decent” level of water, without being destroyed by wild boars. Then, on a night with good ambient humidity, when we checked the pond... we found five adult specimens of runner's toad! The toads of this species (Epidalea calamita) were singing and very “excited”. For the first time, amphibians were detected in the pond and it seemed that they could reproduce there!

Specimen of a runner's toad (Epidalea calamita) inside the pond during the night.

At the beginning of June, with great joy we were able to see waters full of thousands and thousands of tadpoles of various sizes. It seemed very clear that the running toads had found a suitable environment in the pond.

Thousands of small running toad tadpoles on the banks of the pond.

And finally, on June 18, we were able to record the most precocious tiny running toads, which had completed their metamorphosis from tadpole to a sapito of less than 1 cm.

Newly metamorphosed running toads move along the edge of the pond.

A complicated life awaits them and many will become valuable food for other animals, but there are thousands and thousands of them, so we trust that this “r” reproductive strategy will be effective and that several of the tiny running toads will end up growing to a good size, and why not? , return in 2024 to reproduce themselves in the pond built with the efforts of so many good volunteers.

References:

1. Luedtke, J.A. et al. (2023). Ongoing declines for the world's amphibians in the face of emerging threats. Nature 622, 308—314. https://doi.org/10.1038/s41586-023-06578-4

2. González-del-Pliego, P. et al. (2019). Phylogenetic and Trait-Based Prediction of Extinction Risk for Data-Deficient Amphibians. Current Biology 29 (9), 1557-1563. https://doi.org/10.1016/j.cub.2019.04.005

3. Scheele, B.C. et al. (2019). Amphibian fungal panzootic causes catastrophic and ongoing loss of biodiversity. Science 363, 1459-1463. https://doi.org/10.1126/science.aav0379

4. Species profile Batrachochytrium dendrobatidis in the Spanish Catalogue of Invasive Exotic Species MITECO.

5. Alma Amphibia Project. https://www.facebook.com/proyectoalmaamphibia/

6. https://www.youtube.com/@dr.bioblogocanal7975

Fernando Martínez, Biodiversity