PROJECT DESCRIPTION
BACKGROUND
The populations of the endemic Mediterranean fan mussel (Pinna nobilis) have been devastated by a die-off that started in late 2016 in the Western Mediterranean Sea, mainly associated to an infection by the protozoan Haplosporidium pinnae. Since 2016, the disease has spread throughout all the basins of the Mediterranean Sea. Prevalence and subsequent mortality have reached almost 100% in affected populations, causing the ecological extinction of the species in open waters, an unprecedented process in the Mediterranean Sea. The International Union for Conservation of Nature (IUCN) has assessed the species as ‘Critically Endangered’.
Nowadays, the only surviving populations remain in coastal lagoons and deltas, with several thousands of individuals in Delta del Ebro (Spain), Thau Lagoon (France), Venice Lagoon (Italy) and Kaloni and Amvrakikos Gulfs (Greece), whereas only hundreds of individuals remain alive in Mar Menor (Spain), Diana Lagoon (France) and other coastal lagoons, as well as in the Marmara Sea (Turkey). These environments, however, are the most affected by anthropic actions and climate change with regard to the survival of fan mussels in the Mediterranean Sea. These areas are fundamental for the species survival, because they provide a surplus of individuals that could be used for repopulation and experimental purposes.
Therefore, there is an urgent need to preserve the remaining populations, reduce the impacts derived from climate change and direct anthropic actions, and complete the catalogues of individuals and impacts in the reservoirs. Furthermore, some areas have been identified as optimum reservoirs for fan mussels, but repopulation is constrained by the lack of local recruitment. The development of manipulative actions for the movement of individuals among countries is also constrained by the necessity of an international Biosecurity Programme to ensure the security of translocation of individuals. Improving reproduction and maintenance of individuals in captivity is also a need, to ensure a source of specimens that could be used for repopulation, monitoring and further experimentation on the disease and genetic associated factors.
OBJECTIVES
The main objective is to prevent the extinction of fan mussel in the short-medium term.
The specific objectives are to:
- Improve the status of individuals in open waters, optimum sites, and reservoirs, including the monitoring of physico-chemical variables and other environmental conditions potentially associated to the survival of individuals.
- Create an international biosecurity programme for the recuperation of individuals in the field, to be able to share specimens among countries and areas.
- Use the most optimal sanctuary areas for the survival and reproduction of P. nobilis as a management model required for the safe, long-term reintroduction of the species in other reservoir areas.
- Improve the conditions for the breeding of the species in captivity.
- Determine the genetic diversity and genetic factors of disease immunity in fan mussels.
- Develop a treatment to alleviate the effects of the disease in the laboratory, to cure juveniles and improve reproduction in captivity from sick individuals.
- Increase awareness to a global scale, to reduce the possibility of vandalism and illegal collection of the remaining fan mussels, but also to call for broad public collaboration.
- Carry out a socioeconomic study of the impact of the project.
The project focuses mainly on the reservoirs and in the maintenance of individuals for indoor reproduction, since open water populations are missing. In open waters, continuing the protection and monitoring of resistant and hybrid individuals found is also important to safeguard their diversity for future crossbreeding. If no actions are taken, the few resistant individuals found so far will perish after a while without leaving any offspring, and populations in reservoirs will decay, being unable to repopulate if any natural and anthropic factors or the disease kills them.
RESULTS
The project will be undertaken in 32 Natura 2000 sites, with actions for the conservation of the species and its habitat. The area of habitats where loss of biodiversity is halted and reversed are expected to be at least 1 km2 at the end of the project.
Quantified expected results at the end of the project include:
- Monitoring of 2 species improved. Monitoring of Pinna nobilis often also serves to census P. rudis, as well as hybrid specimens between the two species.
- Up to 8 jobs created during the project period.
- To find at least two new resistant individuals in open waters where the disease is assumed to be sure.
- To find at least two new hybrids between Pinna nobilis and P. rudis found at the end of the project. Increasing the resilience in reservoirs.
- Anthropogenic impacts in reservoirs reduced: Expected to find 2,000 individuals at the project end.
- Optimal conditions achieved for keeping animals (30 individuals) in captivity, to allow their proper feeding, reproduction, etc.
- 100 individuals growing under unfavourable conditions translocated and regrouped.
- Different treatments to 30 individuals infected with the protozoan Haplosporidium pinnae successfully carry out, resulting in overcoming the disease.
- One Biosecurity Programme developed for the translocation and manipulation of P. nobilis, applicable to other marine invertebrates at the end of the project.
- At least 3,000 citizens and fishermen informed in priority areas.