''Ballerus ballerus'', also known as the zope or the blue bream, is a species of
cyprinid fish
Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest vert ...
native to
Eurasia
Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...
.
Description
''Ballerus ballerus'' is one of the more streamlined
breams, with a more laterally compressed body (especially towards the tail) and an upturned mouth.
[ The eye is small][ It has small scales and the ]lateral line
The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...
consists of 67-75 scales. It is a pale silvery colour with either pale yellowish or colourless fins. They are normally 25–35 cm in length but occasionally can be up to 40 cm.anal fin
Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...
during the spring spawning season.[
]
Distribution
''Ballerus ballerus'' is found in the large lowland rivers draining to the Baltic Sea
The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain.
The sea stretches from 53°N to 66°N latitude and from ...
, although it is not found in northern Sweden and Finland north of 62°N; the Weser
The Weser () is a river of Lower Saxony in north-west Germany. It begins at Hannoversch Münden through the confluence of the Werra and Fulda. It passes through the Hanseatic city of Bremen. Its mouth is further north against the ports of Bre ...
and Elbe
The Elbe (; cs, Labe ; nds, Ilv or ''Elv''; Upper and dsb, Łobjo) is one of the major rivers of Central Europe. It rises in the Giant Mountains of the northern Czech Republic before traversing much of Bohemia (western half of the Czech Repu ...
draining into the North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...
; the Black Sea
The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Roma ...
; the Don
Don, don or DON and variants may refer to:
Places
*County Donegal, Ireland, Chapman code DON
*Don (river), a river in European Russia
*Don River (disambiguation), several other rivers with the name
*Don, Benin, a town in Benin
*Don, Dang, a vill ...
draining into the Sea of Azov
The Sea of Azov ( Crimean Tatar: ''Azaq deñizi''; russian: Азовское море, Azovskoye more; uk, Азовське море, Azovs'ke more) is a sea in Eastern Europe connected to the Black Sea by the narrow (about ) Strait of Kerch, ...
; and the Volga
The Volga (; russian: Во́лга, a=Ru-Волга.ogg, p=ˈvoɫɡə) is the List of rivers of Europe#Rivers of Europe by length, longest river in Europe. Situated in Russia, it flows through Central Russia to Southern Russia and into the Cas ...
and Ural which drain into the Caspian Sea
The Caspian Sea is the world's largest inland body of water, often described as the world's largest lake or a full-fledged sea. An endorheic basin, it lies between Europe and Asia; east of the Caucasus, west of the broad steppe of Central Asia ...
, although it is rare in the Ural River. Its range spans from the Netherlands in the west to Russia and Georgia in the east.[
]
Habitat and ecology
''Ballerus ballerus'' is occurs in large lowland rivers and eutrophic lakes[ where it feeds on plankton which it catches close to the surface.][ It spawns in Spring, once the ice has thawed, in shallow reedy bays onto the vegetation and the young fish stay in these areas although the adults move into open water to feed.][ Spawning has been recorded on gravel in areas of moderate current.][ This species lives for over 10 years and it breeds for the first time at 3–4 years when they have attained a ]standard length
Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology.
Overall length
* Standard length (SL) is the length of a fish m ...
of 150mm. Spawning is initiated when the water temperature reaches 10 °C and usually lasts for only 1–2 weeks. The females spawn once a year while the males often defend spawning territories along the shoreline. It is known in some areas to migrate long distances to find suitable areas to spawn in. In some regions it will venture into the fresher parts of seas to find food.[
]
Zope software
The Python
Python may refer to:
Snakes
* Pythonidae, a family of nonvenomous snakes found in Africa, Asia, and Australia
** ''Python'' (genus), a genus of Pythonidae found in Africa and Asia
* Python (mythology), a mythical serpent
Computing
* Python (pro ...
-based application server
An application server is a server that hosts applications or software that delivers a business application through a communication protocol.
An application server framework is a service layer model. It includes software components available to a ...
Zope is not named after this species; it is an acronym for "Z Object Published Environment". However, Zope3 was renamed "Bluebream", an alternative vernacular name for ''Ballerus ballerus''.
References
*
{{Taxonbar, from=Q220398
Ballerus
Cyprinid fish of Europe
Fish described in 1758
Taxa named by Carl Linnaeus