Prussian carp
Carassius gibelio
The Prussian carp is an extremely resilient freshwater fish, originally native to East Asia and Siberia, which has spread widely across Europe. It is considered the wild ancestral form of the goldfish and is characterized by its silvery-grey coloration. A biological peculiarity of the species is gynogenesis, where eggs can develop without fusion with male genetic material. It prefers stagnant or slow-moving waters with muddy substrates and low oxygen levels.
Details
Identification
Silvery-grey to lead-colored flanks, high back, dorsal fin with a serrated hard ray, 27-33 scales along the lateral line, peritoneum usually darkly pigmented.
Social behavior
Gregarious, forms large schools especially during the juvenile stage.
Diet
Omnivorous; feeds on zooplankton, small benthic invertebrates, algae, and detritus.
Hunting strategy
Foraging in the bottom substrate and grazing on periphyton on aquatic plants.
Spawning substrate
Aquatic plants (adhesive spawner).
Overwintering
Overwintering in deeper water zones or partially buried in the mud.
Ecology
Ecological role
Strong food competitor for native species like the crucian carp; pioneer species in degraded water bodies.
Natural predators
Pike, pike-perch, otter, cormorant, heron.
Competitor species
Crucian carp (Carassius carassius), common carp, tench.
Ecosystem service
Serves as a prey fish for various predators in otherwise fishless, oxygen-poor waters.
Threats
Not threatened in Europe; its spread is favored by anthropogenic water body alterations.
Scientific profile
Morphology & ID
Coloration
Sides silvery-grey to bronze, back darker (olive-grey), belly whitish-silver. Fins greyish.
Distinguishing features
Silvery-grey coloration, deep-bodied shape, 27-33 lateral line scales. Key diagnostic feature distinguishing it from C. carassius is the black peritoneum and the strongly serrated last unbranched dorsal fin ray.
Confusion species
Crucian carp (Carassius carassius - pale peritoneum, rounded dorsal fin), Common carp (Cyprinus carpio - has barbels), Goldfish (Carassius auratus).
Sexual dimorphism
Externally barely distinguishable; notable for the gynogenetic reproduction of triploid females.
Habitat
Fish region
Bream region; standing waters such as lakes, ponds, and backwaters.
Preferred zone
Benthopelagic; typically stays near the bottom or in the mid-water column.
Flow preference
Stagnophilous to limnophilous; prefers standing or very slowly flowing waters.
Substrate preference
Prefers soft, muddy substrates with abundant detritus and macrophyte growth.
Oxygen requirement
Very low; capable of surviving in extremely hypoxic waters where other fish species perish.
Migration
Migration behaviour
No extensive migrations; only local movements between wintering grounds and spawning areas.