Taxonomic name: Leuciscus idus (Linnaeus, 1758)
Synonyms: Cyprinus idbarus Linnaeus, 1758, Cyprinus idus Linnaeus, 1758, Cyprinus jeses Linnaeus, 1758, Cyprinus microlepidotus Ekström, 1835, Cyprinus orfus Linnaeus, 1758, Cyprinus orphus Linnaeus, 1758, Idus idus (Linnaeus, 1758), Idus melanotus orientalis Sinitzyn, 1900, Idus melanotus Heckel, 1843, Idus miniatus Bonaparte, 1845, Idus miniatus Heckel & Kner, 1858, Idus oxianus Kessler, 1877, Leuciscus idus auratus Bade, 1901, Leuciscus idus idus sibiricus Kirillov, 1958, Leuciscus idus idus (Linnaeus, 1758), Leuciscus idus lapponicus Günther, 1868, Leuciscus idus oxianus (Kessler, 1877), Leuciscus neglectus Selys-Longchamps, 1842, Squalius oxianus Kessler, 1877
Common names: Gäse (German), golden orfe (English), Goldorfe (German), Iaz (Russian), id (Swedish), ide (English), ide (French), ide dorée (French), ide mélanote (French), ide rouge (French), ido (Italian), jalec tmavy (Czech), jalec tmavý (Slovak), jasek (Czech), jász (Hungarian), jaz (Polish), jelec jesen (Czech), Jesen (German), jesen nížinný (Czech), jesen obecný (Czech), jez (Slovenia), jezuve (Czech), leukiskos-tsiróni (Greek), lugojanel (Romanian), mazdruga (Bulgarian), Nerfling (German-Austria), orfe (German), Orfe (English), orff (Welsh), rimte (Danish), ryba májová (Czech), säyne (Finnish), silver orfe (English), strandkarpe (Danish), vaduvita (Romanian), vederbuk (Norwegian), véron (French), Weißfisch (German), winde (Dutch), yaz (Russian-Ukraine)
Organism type: fish
Leuciscus idus (orfe) are a large-bodied freshwater fish native to Europe. They are valued as a sport fish in many countries and have been introduced to a number of locations for this purpose. Concerns have been raised about their potential to damage to native aquatic ecosystems but there seems to be a lack of information regarding any proven effects.
Orfe are a chunky fish, with the back and belly dinstinctly arched. The head is small and bluntly pointed, and the tail has a definite fork in it.
Two colour forms exist. The wild form is a greyish-olive colour on the back and upper sides, paling to silver on the sides and a silvery-white on the belly. Both anal and pelvic fins are a reddish colour. The ornamental variety of orfe has a bright orange back, silvery-orange sides and belly, and bright orange tail and dorsal fin. These two colour morphs are known as 'silver orfe' and 'golden orfe' respectively. Golden orfe populations may revert to the wild colouration over time (McDowall, 2000).
lakes, water courses
Orfe inhabit clear, clean pools of medium-to-large rivers, ponds and lakes (FishBase, 2004). Retreats into deep holes during winter (McDowall, 2000).
There is no information regarding the impacts of orfe in New Zealand as it is confined to one location. Most concerns appear to be based on the fact that it is in the same family as the highly invasive European carp (Cyprinus carpio), which has caused damage to some aquatic ecosystems where it has been introduced Australia, New Zealand and the USA. However, orfe can tolerate a higher level of salinity than any other cyprinid fish so may be able to colonise brackish water and estuarine habitats. These are often critical bottlenecks for anadromous (migrating up rivers from the sea to breed in fresh water) species. The potential for orfe to cause problems in countries where its natural controls are absent is of concern (David Rowe pers.comm., 2005).
A popular sporting fish among coarse anglers (McDowall, 2000), and in some areas of Europe there is also commercial fishery production (McDowall, 1990). The golden orfe variant is valued as an ornamental fish, as it is just as suitable as goldfish for small ponds (McDowall, 1990).
The maximum reported age for this species is 18 years, and the maximum published weight is 4kg (FishBase, 2004).
Native range: Natural range is across Europe, from Scandinavia to Siberia (McDowall, 2000).
Known introduced range: Introduced to the UK, Netherlands, New Zealand, US, and France (FishBase, 2004).
Introduction pathways to new locations
Pet/aquarium trade: Golden orfe are valued as ornamental pond fish
Smuggling: There have been instances of orfe being illegally introduced to new locations by anglers.
Local dispersal methods
For ornamental purposes (local): Golden orfe are valued as ornamental pond fish
Intentional release: Orfe may be introduced to new locations for ornamental purposes or angling.
Natural dispersal (local): Populations can expand their range within connected waterbodies by swimming.
Preventative measures: The use of potentially invasive alien species for aquaculture and their accidental release/or escape can have negative impacts on native biodiversity and ecosystems. Hewitt et al, (2006) Alien Species in Aquaculture: Considerations for responsible use aims to first provide decision makers and managers with information on the existing international and regional regulations that address the use of alien species in aquaculture, either directly or indirectly; and three examples of national responses to this issue (Australia, New Zealand and Chile). The publication also provides recommendations for a ‘simple’ set of guidelines and principles for developing countries that can be applied at a regional or domestic level for the responsible management of Alien Species use in aquaculture development. These guidelines focus primarily on marine systems, however may equally be applied to freshwater.
Copp et al, (2005) Risk identification and assessment of non-native freshwater fishes presents a conceptual risk assessment approach for freshwater fish species that addresses the first two elements (hazard identification, hazard assessment) of the UK environmental risk strategy. The paper presents a few worked examples of assessments on species to facilitate discussion. The electronic Decision-support tools- Invasive-species identification tool kits that includes a freshwater and marine fish invasives scoring kit are made available on the Cefas (Centre for Environment, Fisheries & Aquaculture Science) page for free download (subject to Crown Copyright (2007-2008)).
Feeds on crustaceans, insect larvae, worms, snails as well as some fish and vegetation (McDowall, 2000).
Spawns in schools over weed beds or gravel in shallow areas. Produces thousands of pale yellow eggs c. 2mm in diameter. Hatching occurs in one to two weeks, producing young fish 8-10mm long (McDowall, 2000).
Matures at three to four years of age. Spawning occurs in spring (McDowall, 2000).
Reviewed by: Dr. David Rowe, NIWA (National Institute of Water & Atmospheric Research). Hamilton New Zealand.
Principal sources: McDowall, R. M. 2000. The Reed field guide to New Zealand freshwater fishes. Auckland, Reed.
FishBase, 2004. Species profile Leuciscus idus Ide
Compiled by: IUCN SSC Invasive Species Specialist Group
Updates with support from the Overseas Territories Environmental Programme (OTEP) project XOT603, a joint project with the Cayman Islands Government - Department of Environment
Last Modified: Monday, 4 October 2010