Identifying True Roach

Roach x rudd hybrid from the River Frome

I caught this roach x rudd hybrid from the Dorset Frome recently. The river is famed for its big roach and rightly so, but where I was fishing a field drain enters the river through a sluice. The field drain has lots of roach and rudd, and I suspect the hybrid came from there as I also had some rudd and plenty of roach.

The close ups of the fish show how difficult it can be to tell the difference between a hybrid roach x rudd and the true species. The mouth gives nothing away. The dorsal fin is a little too far back for a true roach. The anal and tail fins have a stronger colouration than roach but not as intense as rudd. These aspects are all comparative ones. The count of the anal fin rays and lateral line match both rudd and roach. The overall shape is both rudd and roach like. Small wonder that only DNA testing offers absolute proof that such a fish is not a true roach or rudd if it were a potential record breaker.