Description and characteristics
The crucian carp (Carassius auratus) is a medium-sized cyprinid with a deep, robust, laterally compressed body covered with large scales. Colouring ranges from grey-green to bronze or golden. It is distinguished by the absence of barbels, unlike the common carp.
Habitat and distribution
The crucian carp inhabits still and slow-flowing waters of the Danube Delta — ponds, lakes, canals and flooded areas. It is extremely adaptable, tolerating low oxygen, extreme temperatures and turbid water.
Diet and behaviour
It is omnivorous, feeding on benthic invertebrates, larvae, plants, detritus and organic debris. It lives in schools and is very resilient to difficult conditions.
Reproduction
Spawning occurs in spring and summer at 14–20°C. Females lay numerous eggs on vegetation and bottoms, and the fry grow quickly. It is a prolific species.
Economic and ecological importance
The crucian carp has local economic value, being widely caught for consumption. Ecologically, it occupies various niches and contributes to freshwater fish stocks.
Threats and conservation
It is a very resilient species, less sensitive to pollution than other cyprinids. Nevertheless, responsible management and protection of flooded habitats remain important.
Fishing and legal minimum size
The crucian carp is one of the most sought-after fish for recreational fishing in the Delta. In the table of minimum legal sizes, the crucian carp (Carassius auratus) has a minimum legal size of 20 cm.
Conclusion
The crucian carp is a hardy, valuable cyprinid, present throughout the waters of the Danube Delta.