A new release of fartet fish (Aphanius iberus) in the Natural Area of ​​the Mouth of the Guadalhorce River, with the reintroduction of 350 copies from the Center for Breeding and Conservation of Endangered Fish (CECCPA) in Los Villares, Córdoba.
The action, promoted by the Ministry of Sustainability and Environment, seeks strengthen genetic diversity and consolidate the most relevant nucleus of this species in Andalusia, in coordination with that of the Adra Lagoon, from the parents of the only one natural Andalusian population located in the Adra river basin (AlmerÃa).
Reintroduction in the Guadalhorce area
The Malaga enclave, of artificial origin but of great value For biodiversity, it is home to several bodies of water with variable salinities depending on rainfall and the coastal aquifer, which provides an ideal setting for the species at different times of the year.
Since 2017 they have been released in this space more than 5.200 fartets, creating a macronucleus in the large lagoon and, to a lesser extent, in the old river. Regular releases have avoided genetic bottlenecks and have contributed to maintaining viable populations under changing environmental conditions.
Ecological advantage over gambusia
The fartet is characterized by its high resistance to hypersaline environments and high temperatures, which allows it to compete with an advantage against the invasive species Gambusia (Gambusia holbrooki)While gambusia does not tolerate salinities above 35-37g/L, the fartet can withstand concentrations of up to 140 g / L.
The pressure of the Gambusia has historically displaced the fartet to marginal areas; however, the high salinity habitats of the Guadalhorce favor the native species, a problem that sometimes leads to the elimination of an invasive fishIn summer, specific episodes of eutrophication and oxygen deficiency in stagnant areas, so work is being done to improve water quality.
Scientific criteria and work phases
The reintroduction follows the guidelines of the IUCN, prioritizing water bodies where salinity limits the expansion of the invader and improves the fartet competitionThis habitat selection is supported by physicochemical analysis and ongoing technical monitoring.
The program began by consolidating a founding nucleus in the eucalyptus lagoon and, once stabilized, extended the presence of the species towards the north of the old river, increasing the number of points with suitable conditions.
Among the management measures, the team studies the regulation of contributions from the Guadalhorce River to stabilize salinity ranges, in addition to reinforcing the aquatic vegetation and ensure riparian refuges that promote shelter and reproduction.
Challenges and next steps
Challenges such as the Gambusia control In certain lagoons, there are signs of adaptation to salinities higher than those recorded in the past, which requires adjusting management actions.
Future success requires a long-term vision based on research, continuous monitoring and coordination between administrations, breeding centers and technical staff, whose work has been key to avoiding genetic bottlenecks and sustain the population.
In addition to its status as an endangered species, the fartet plays a ecological function useful: contributes to the natural control of mosquito larvae, with positive effects on nearby urban areas during the warmer months.
With this new release of 350 copies, the Board's program advances in the consolidation of the fartet in the Guadalhorce, supported by scientific criteria, adaptive management and a collaborative network that has already allowed the reintroduction more than 5.200 individuals 2017 since.
