This pond, located in the saltworks of San Pedro del Pinatar, has undergone many changes in recent decades, even being in the early eighties the focus of attention of developers for its urban development. However, the progress in the declaration of protected areas and the protection of the natural environment has allowed this pond to reach our days with a certain naturalness and state of conservation. At the beginning of the 1990s, the Coterillo pond was proposed by the regional administration as a research pond, maintaining a certain connection with the Mediterranean, and highlighting among its main functions “to ensure the maintenance of the populations of spanish toothcarp (Aphanius iberus)”, a small endangered fish with a reduced distribution at regional level. Finally, the difficulty in the management and maintenance of this pond led to its isolation, drastically increasing the salinity of the environment and leading to the local extinction of the spanish toothcarp in 2012.
Recovery of the Coterillo pond within the framework of the LIFE SALINAS project.
The ecological and environmental recovery of the Coterillo pond and its surroundings is part of action C2 of the LIFE SALINAS Project. In order to achieve the proposed objectives, the project proposed the incorporation of this pond in the initial phases of the water circuit of the saltworks, thus ensuring the maintenance of a permanent sheet of water and a salinity ranging between 40 and 60 g/l, ideal environmental conditions for spanish toothcarp populations.
On the other hand, the nesting habitat available for the waterbird community has been increased and improved, reinforcing and extending the pre-existing islands and creating new salt marshes. In addition, an attempt has been made to encourage the nesting of the common shelduck (Tadorna tadorna) by installing specific nesting boxes for the species, which are integrated into the substrate of the islands and motes.
How is biodiversity responding?
Since the beginning of the project, the LIFE SALINAS technical team has been carrying out biological monitoring work in the salt ponds, with the aim of evaluating the response of the biodiversity to the actions carried out and thus assessing their success. In this sense, bird censuses and sampling of spanish toothcarp and aquatic macroinvertebrates are carried out in the Coterillo pond.
After the execution of the works of action C2, at the end of 2020, the biodiversity response seems to be very positive. The recolonisation of this pond by spanish toothcarp individuals from other ponds in the salt circuit took place a few weeks after the water surface was restored, and their reproduction and the establishment of their populations were observed in subsequent months.
The community of aquatic macroinvertebrates, a key fauna component in the trophic structure of these ecosystems, has been enriched, and species of aquatic coleoptera, such as Nebrioporus ceresyi, Ochthebius corrugatus or Enochrus bicolor, have also been detected as indicators of quality in saline environments.
The response of the avifauna has not yet been significant, although we expect that with the progressive development of the ecosystem and the naturalisation of the environment, the breeding population of waterbirds will increase.
The results obtained so far are encouraging, forecasting a good evolution of biodiversity in the Coterillo pond in the coming years. It should be noted that this action is of a permanent nature, as the inclusion of the Coterillo pond in the salt circuit will allow maintaining its water supply and the stability of the environment beyond the period of action of the LIFE SALINAS Project, ensuring in turn the maintenance of the spanish toothcarp populations, and of biodiversity as a whole.