Atlantic bonito

The Atlantic bonito is a small, muscular member of the tuna and mackerel family, built like a polished metal spindle. The back is steel blue-green and carries somewhere between five and eleven dark stripes that run obliquely forward and downward, a pattern no other local tuna shows on its upper body. The flanks and belly are bright silver, the first dorsal fin is long and low, and a row of small separate finlets runs from the second dorsal and anal fins to the stiff, crescent tail. The mouth is full of small conical teeth. Divers in Malta usually meet fish of 40 to 55 cm, though the species can reach roughly 90 cm.

Bonito are open-water hunters that travel in fast, tight schools and follow shoals of sand smelt, picarel, sardine and bogue. Around the Maltese islands they show up where deep water comes close to the rock: the drop-offs at Ċirkewwa and Aħrax, the outer reefs of Comino, the walls at Dwejra and Xlendi, and along the Delimara and Munxar cliffs. They come in from the blue, sweep once or twice through the bait, and leave. Most sightings happen in the top 25 metres, often while you are still hanging in open water at the start or end of a dive.

They are a warm-season fish here. Numbers build from late spring, peak through late summer and autumn when the water sits in the mid twenties, and thin out again in winter. Maltese fishermen troll for plamtu along the same headlands, and it is a familiar, cheap, strongly flavoured fish on the market slab in autumn.