The Atlantic bonito, (Sarda sarda) as its name suggests, is not a fish typically found swimming in the murky waters of the North Sea, so fisherman Peter Caunter was surprised to find one among his catch.
Mr. Caunter was fishing for sea bass off the Gabbard sandbanks just offshore at Harwich, Essex when he landed the unusual specimen. Measuring 55cm and weighing in at 1.7kg, the fish was donated to scientists at the Centre for Environment, Fisheries & Aquaculture Science (Cefas), in Lowestoft, for further study.
Cefas' Dr Jim Ellis said: "Atlantic bonito tend to be found in warm waters, and this is an unusual species to be caught off East Anglia.
"There have been other oceanic fish reported from the North Sea in recent months, including blackfish and Ray's bream. We're always very interested in hearing about any unusual fish being caught, as it enables us to learn more about not only unusual species, but how the seas off Britain may be changing."
The Atlantic bonito is occasionally caught by fishermen off the south west coast of England, but there are almost no records of the species in the southern North Sea. The small tuna species is closely related to mackerel and is usually a schooling fish migrating throughout much of the Atlantic, as well as the Mediterranean and Black Sea.
Growing to around 90cm/36" and a with maximum weight of 11kg it is a predatory species, feeding on smaller schooling fishes, squid and other invertebrates.