Ballerus ballerus (Linnaeus, 1758)
Zope
photo by Busse, K.

Family:  Leuciscidae (Minnows), subfamily: Leuciscinae
Max. size:  49 cm TL (male/unsexed); max.weight: 1,085.0 g
Environment:  benthopelagic; freshwater; brackish, potamodromous
Distribution:  Eurasia: large rivers draining to Baltic Sea (absent in northern Sweden and Finland north of 62°N), North Sea (Weser, Elbe), Black Sea, Sea of Azov (Don) and Caspian Sea, where it is abundant in Volga, rare in Ural.
Diagnosis:  Differs from Ballerus sapa by having superior mouth, 62-77 scales on lateral line, and small eye with diameter about 2/3 of snout length in individuals larger than 10 cm SL (Ref. 59043).
Biology:  Occur in large lowland rivers with backwaters and also in eutrophic lowland lakes. Feed mainly on zooplankton in open water of backwaters and other still water bodies. Spawn along shores of rivers or in backwaters on submerged vegetation and also on gravel in moderate current. Migrate upriver in long distances to suitable spawning sites. Juveniles stay in backwaters and flooded zones along rivers. Enter freshened parts of seas to forage. Life span reaches more than 10 years. Locally threatened by habitat alterations along river banks (Ref. 59043).
IUCN Red List Status: Least Concern (LC); Date assessed: 05 March 2010 Ref. (130435)
Threat to humans:  harmless


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