Discovery of hybrid sharks off Australia’s east coast
Marine scientists has discovered that sharks on Australia’s east coast display a mysterious tendency to interbreed, challenging several accepted scientific theories regarding shark behaviour. The scientists found widespread hybridisation in the wild between two commonly caught shark species.
The Australian black tip shark (Carcharhinus tilstoni) and the common black tip shark (C. limbatus) have overlapping distributions along the northern and eastern Australian coastline.
Using both genetic testing and body measurements, 57 hybrid animals were identified from five locations, spanning 2000km from northern NSW to far northern Queensland. Although closely related, the two species grow to different maximum sizes and are genetically distinct.
This is the first discovery of sharks hybridising and suggests that other closely related shark and ray species around the world may be doing the same thing.
Dr Jennifer Ovenden, University of Queensland; Dr Colin Simpfendorfer, Fishing and Fisheries Research Centre, James Cook University
