Description and characteristics
The bighead carp (Hypophthalmichthys nobilis) is a large cyprinid with a big head, low-set eyes and a laterally compressed body covered with small scales. It has a grey colour with dark spots on the flanks.
Habitat and distribution
It prefers warm, plankton-rich waters, being introduced into lakes and ponds of the Danube Delta. It lives in schools in open waters.
Diet and behaviour
It is a planktivore, feeding on plankton and microscopic algae, filtering them through specialised gills. A schooling species, active in nutrient-rich waters.
Reproduction
Spawning occurs in flowing waters in spring, with females laying pelagic eggs. In ponds, natural reproduction is rare, so it is bred in aquaculture.
Economic and ecological importance
It has value in aquaculture and fishing, being widely consumed. Ecologically, it helps reduce excess plankton, but can compete with native species.
Threats and conservation
It is an introduced species, and its impact on native ecosystems must be managed. It can affect populations of native plankton feeders.
Fishing and legal minimum size
It is fished commercially and for recreation. In the table of minimum legal sizes, the bighead carp (Hypophthalmichthys nobilis) has a minimum legal size of 40 cm.
Conclusion
The bighead carp is a planktivorous cyprinid important in aquaculture and fishing, but with an impact to be managed in native ecosystems.