Zoltán Szalóky, Ágnes Maroda, and Péter Sály, fish ecologists of the ELKH Centre for Ecological Research (CER), have been conducting fish population surveys for the third year as part of the Centre's Public Utility Monitoring project, with the professional collaboration of Balázs Tóth (Duna-Ipoly National Park Directorate) and Attila Mórocz (Duna-Dráva National Park Directorate). At the end of June, near Mohács, the researchers caught numerous zingel juveniles with a body length ranging from 32 to 42 mm, originating from this year's reproduction. This is a delightful surprise as this native fish species, which is highly protected in Hungary, is rarely encountered.
Zingel juveniles originating from this year's reproduction on the body length measuring tray (Photo: Zoltán Szalóky)
Zingel (Zingel zingel) is a highly protected, bottom-dwelling native percid fish species in Hungary, distributed throughout the catchment basin of the Danube and Dniester rivers. Its body is elongated and spindle-shaped, with an inferior mouth, and its scales are deeply embedded in the skin, known as ctenoid scales, which give it a rough texture when held, similar to other percid fish. The typical body length of adult individuals is between 20 to 30 cm. It feeds on invertebrates and smaller fish in the gravelly, sandy, and fast-flowing riverbeds of large rivers. Breeding occurs during the spring warm up of waters in March and April. As it usually resides in areas away from the shore, it is only occasionally encountered during scientific fish population surveys conducted along the Danube's inshore habitat. If spotted, it is mostly in the form of juveniles or adult individuals.
Zingel juveniles (Photo: Zoltán Szalóky)
Individuals of zingel (larger specimen) and its close relative, the Danube streber (smaller specimen). The silvery glow in the eyes of the nocturnally active zingel is caused by the light-reflecting layer (tapetum lucidum) connected to their retinas.(Photo: Ágnes Maroda)
Due to its rare occurrence, it was a delightful surprise for the researchers when they caught numerous zingel juveniles with a body length ranging from 32 to 42 mm, originating from this year's reproduction near the town of Mohács at the end of June.
Deep-water electric fishing net before lowering.(Photo: Zoltán Szalóky)
Zoltán Szalóky, Ágnes Maroda, and Péter Sály, CER fish ecologists have been conducting fish population surveys for the third year as part of the Centre's Public Utility Monitoring project, with the professional collaboration of Balázs Tóth (Duna-Ipoly National Park Directorate) and Attila Mórocz (Duna-Dráva National Park Directorate). In the main channel of the Danube, the researchers sampled the inshore habitat during the night, while the deeper offshore habitats during the day. In the offshore samples, they caught a significant number of adult individuals of the Danube streber (Zingel streber), a close relative of the zingel, also highly protected. Additionally, alongside the zingel, they found this year's offspring of the protected schraetzer (Gymnocephalus schraetser). This species shares a similar habitat and lifestyle with the zingel species but has a stronger affinity for sandy substrate and moderate flow.
Nocturnal sampling in the inshore habitat.(Photo: Ágnes Maroda)