CALENDAR:
START: MARCH 2020
FINAL: OCTOBER 2020
GOALS:
- Improving the ecological status of three ponds in the custody of Riudarenes:
- Eliminate exotic fish by promoting herpetofauna
- Unclog and recover the depth of the ponds
- Control ruderal vegetation and encourage aquatic vegetation
- Renew the exhibition at the Sils Lake Information Center
BUDGET:
- TOTAL BUDGET OF THE PROJECT: 21.290€
- FINANCERS:
- Departament de Territori i sostenibilitat (Generalitat de Catalunya)
SUMMARY:
The region of La Selva has a close history with water, as its particular orography with an extensive central plain surrounded by mountains favored the creation of numerous rivers, ponds and wetlands. The pond turtle (Emys orbicularis) and a wide variety of amphibians proliferate in this environment. Evidence of this is that La Selva is considered an "Area of Special Interest for Reptiles and Amphibians" by the "Spanish Society of Herpetology". Unfortunately, there is very little left of that aquatic environment today. Changes in land use, mainly due to the acquisition of land for agriculture, built-up areas and infrastructure, have reduced the presence of wetlands to small scattered and fragmented ponds.
Despite the reduction of this biodiversity habitat, in the plain of La Selva we find the best-preserved pond turtle population in Catalonia, with an estimated population size of about 170 in Riudarenes, and a great wealth of amphibians and reptiles. This is probably due to the fact that the different permanent ponds, temporary ponds, irrigations and streams, form a network of wetlands that have given this population a great resilience to changes in habitats and landscape.
Among the species found in these environments are some protected species that are included in the Annex of Legislative Decree 2/2008 on the protection of animals:
- Pond Turtle (Emys orbicularis)
- Stream Turtle (Mauremys leprosa)
- Water snake (Natrix maura)
- Necklace Snake (Natrix astreptophora)
- Salamander (Salamander salamander)
- Palm newt (Lissotriton helveticus)
- Green newt (Triturus marmoratus)
- Totally (Alytes obstetricans)
- Spurs (Pelobates cultripes)
- Dotted Frog (Pelodytes punctatus)
- Common Toad (Bufo spinosus)
- Running Toad (Epidalea calamita)
- Reineta (southern) (Hyla meridionalis)
Thus, La Plana de la Selva is a space of great value for biodiversity and marshy habitats. Unfortunately, it is not free from pressures that threaten its natural values, and that require monitoring by environmental organizations and local authorities, as well as management and maintenance actions. The main pressures facing the wetlands on the plain of La Selva are:
Drying: In recent years, several ponds have dried up completely, or old permanent ponds have become temporary. The main causes are the increase in drought episodes and their severity, probably framed by a trend of climate change. These episodes are also compounded by overexploitation of the aquifer and dredging of streams and canals, which causes alterations in the aquifer and promotes the drying up of ponds. Examples of this are the Esplet and Can Prats ponds, or the Sils lake itself, which dried up completely last summer. This trend can be very worrying for those ponds in which the flood period is not enough to allow the development of amphibian larvae until they metamorphose.
Clogging: Ponds are usually sinks of matter, meaning that they contain a lot of sediment and organic matter, but they do not come out. This causes the pond to gradually fill up and lose depth and become homogenized. This makes it more vulnerable to drought and reduces the conditions for a greater species richness.
Vegetation growth: Due to the clogging process, in many cases the vegetation that grows around the ponds gradually closes and ends up completely covering the space. The closure of the trees prevents the entry of the sun, and the growth of hedges, or riparian vegetation inside the pond can end up making it disappear.
Invasive species: In many ponds, invasive flora species have been detected that can cause a decline in the quality of the ecosystem. We also find species of invasive wildlife that can harm native wildlife, or even exclude it from space. The case of fish is particularly worrying, as they devour amphibian spawning, making it impossible to recruit people, in addition to the impact they have on the invertebrate community.
To deal with these pressures and preserve the protected species found there, this project aims to improve the ecological conditions of three emblematic pond systems in the Riudarenes area, in order to:
- Favor the population center of the pond turtle in the Mas Vern pond
- Favor the amphibian community of the Can Maidó ponds
- Recover the temporary pond of Can Barrot for the reproduction of amphibians
- Foster society's awareness of wetlands and their biological richness
The project is part of the territorial area of the plain of La Selva, between the municipalities of Riudarenes and Sils. In this area, the Emys Foundation has a network of custody agreements to conserve wetlands and herpetofauna. The actions proposed in this project will be developed in three wetlands included in the Catalog of Wetlands of Catalonia, and which maintain custody agreements with the Emys Foundation: are the ponds of the meadows of Mas Vern (IZHC-05003415), the ponds of Can Maidó (on Turous d'en Bulous, IZHC-05003412) and the small pond of the Can Barrot estate (IZHC-05003410). All three areas are of great value for the conservation of the pond turtle and the amphibian species already described. Lastly, there is an action to disseminate and raise awareness about the wetlands of the Selva plain in Sils, taking advantage of the existence of the Lake Information Center.