Starting/ending date: 01/03/2019 – 30/04/2021
Total financing: 24,900.00 €
National project 
Dr Stamatis Zogaris, Inland Waters

Schinias in Marathon, located 40 KM from Athens, was established as a National Park in 2000. It was initially created under the pressure of the need to build a new rowing reservoir facility for the 2004 Olympic Games. Before the site was designated for this Olympic sport, the Schinias wetland did not have any degree of institutionalized distinction as a “protected area”. Today the situation of the wetland is very different and much of the wetland has partially recovered from severe degradation; it is a designated Natura 2000 protected area. The wetlands of Schinias cover about 480 hectares, along with the Olympic rowing reservoir that is directly connected to the rest of the wetland. The creation of the Schinias Reservoir (​​75 hectares) from the spring waters of the adjacent Makaria Spring and the channeling of part of the water in the former degraded swamp revived the ecological value of formerly partially drained wetlands. Despite the positive aspects, there are serious water management problems and these negatively impact biodiversity.

Since 2009 mass fish deaths have been reported at the overflow weirs near the new reservoir. These fish deaths (many tons of eels in 2016) also impact the population of the endemic Marathon Minnow (Pelasgus marathonicus). The weirs that allow overflowing spring waters into the wetland from the reservoir attract the fish in large numbers because aquatic conditions drastically change in summer and autumn (dissolved oxygen levels drop and salinity rises). This periodic degradation of aquatic conditions causes mass fish kills and stress throughout most of the wetland.

This project is a collaboration among the Fisheries Department of the Region of Attika, the Schinias National Park Management Body and HCMR. Τhe purpose of the 26 month research was to deal with the extensive fish-kill phenomena particularly impacting the European eels in Schinias-Marathon National Park. Through the investigation of environmental conditions and specialized ichthyological research, it included the design of technical solutions (a fish-pass) as well as the development of technical methods for mitigating damage to the fish populations and monitoring the phenomenon.