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A molecular approach to detect hybridisation between crucian carp (Carassius carassius) and non-indigenous carp species (Carassius spp. and Cyprinus carpio)

Hänfling, B.; Bolton, P.; Harley, M.; Carvalho, G. R.


Dr Bernd Haenfling
Senior Lecturer/ Chair of the Evolutionary Biology Group (EvoHull)

P. Bolton

M. Harley

G. R. Carvalho


1. Releases of non-native fish into the wild is an increasing problem posing considerable ecological and genetic threats through direct competition and hybridisation. 2. We employed six microsatellite markers to identify first generation hybrids and backcrosses between native crucian carp (Carassius carassius) and introduced goldfish (C. auratus) and common carp (Cyprinus carpio) in the U.K. We also investigated the genetic characteristics of the taxonomically controversial gibel carp (Carassius spp.) from sites across Europe. 3. Natural hybridisation between goldfish and crucian carp occurs frequently, although hybrids between all other species pairs were observed. Only 62% of British crucian carp populations (n = 21) consisted exclusively of pure crucian carp. In some populations hybrids were so frequent, that no pure crucian carp were caught, indicating a high competitive ability of hybrids. 4. Most hybrids belonged to the F1 generation but backcrossing was evident at a low frequency in goldfish x crucian carp hybrids and goldfish x common carp hybrids. Furthermore, some local populations had high frequencies of backcrosses, raising the opportunity for introgression. 5. Gibel carp from Germany and Italy belonged to two triploid clonal lineages that were genetically closely related to goldfish, whereas all individuals identified from British populations proved to be crucian carp x goldfish hybrids. 6. Our study suggests that the release of closely related exotic cyprinids not only poses a threat to the genetic integrity and associated local adaptations of native species, but may also contribute to shifts in community structure through competitive interactions.


Hänfling, B., Bolton, P., Harley, M., & Carvalho, G. R. (2005). A molecular approach to detect hybridisation between crucian carp (Carassius carassius) and non-indigenous carp species (Carassius spp. and Cyprinus carpio). Freshwater biology, 50(3), 403-417. doi:10.1111/j.1365-2427.2004.01330.x

Journal Article Type Article
Acceptance Date Nov 11, 2004
Online Publication Date Jan 19, 2005
Publication Date Mar 1, 2005
Print ISSN 0046-5070
Electronic ISSN 1365-2427
Publisher Wiley
Peer Reviewed Peer Reviewed
Volume 50
Issue 3
Pages 403-417
Keywords Aquatic Science
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