Atlantic saury

At first glance you might take it for a garfish: the body is long and slender, and both jaws are drawn out into a beak. FAO’s species identification sheets for the Mediterranean and Black Sea describe the body as elongate and moderately compressed; in adults both jaws form a thin, fragile beak, the lower slightly longer than the upper. The real giveaway is near the tail: the dorsal and anal fins sit far back on the body, and their last rays are turned into small separate finlets. FAO counts 5–6 finlets behind the dorsal fin and 5–7 behind the anal fin; the tail fin is forked. On colour, FAO gives the back of adults as olive to dark green or light brown, and bluish in the young. A silver stripe about as wide as the eye runs along the flanks; the flanks and belly are silvery, often with a coppery-gold tint, and there is usually a small green spot below the base of the pectoral fin. The young are more misleading. Bigelow and Schroeder’s Fishes of the Gulf of Maine (1953) says the jaws only begin to lengthen once the young fish reach about 40 millimetres, that the lower jaw pulls ahead first, and that fish of 100–150 millimetres look more like little halfbeaks than like their parents.

The two fish belong to the same order, Beloniformes, but to different families. WoRMS places the Atlantic saury in Scomberesocidae; FishBase lists the garfish (Belone belone, /en/turler/zargana on this site) in Belonidae. FAO’s Belonidae sheet sums up the difference in one line: in the saury’s family the rear rays of the dorsal and anal fins are turned into separate finlets, in the garfish they are not. Bigelow and Schroeder likewise write that this fish resembles the gars in its slender form and prolonged jaws but differs from them in its row of 5–6 small finlets above and below. The FAO sheets list other differences too. The garfish has relatively large, widely spaced teeth, while the saury’s teeth are tiny and set in narrow bands. The garfish has 16–20 rays in the dorsal fin and 19–23 in the anal fin, a dark blue back and a dark blue band along the flank. Garfish eggs stick to plants or floating objects with adhesive filaments, whereas the saury releases pelagic eggs into open water. FAO describes the garfish as a coastal surface fish and the saury as oceanic. The names can get mixed up as well. The local names FishBase records for Türkiye are ‘zurna’ and ‘zurna balığı’. The name table in the study by Ulman and colleagues, published in Mediterranean Marine Science in 2013, which reconstructs Türkiye’s marine fisheries catches, also gives ‘zurna’ for the Atlantic saury and ‘zargana’ for Belone belone. The Turkish name recorded in WoRMS, however, calls this species ‘zargana’, so if you see ‘zargana’ in a source, it is worth checking the scientific name.

FishBase describes the species as oceanic and schooling, found at depths of 0–30 metres and highly migratory; it gives its range as both sides of the North Atlantic and the whole of the Mediterranean, including the Adriatic and the Aegean. According to the FAO sheet, in the Mediterranean it lives mainly in the western and central basins, travels in surface waters in schools of several thousand, often leaps out of the water, probably to escape predators, and can enter bays and estuaries. It feeds on zooplankton and makes feeding migrations from its spawning grounds to colder, plankton-rich waters. FishBase says it is preyed on by tunas, marlin, bluefish and cod. For Türkiye the sources are limited. FishBase’s record for Türkiye lists the species as native and, based on the 2007 list by Fricke, Bilecenoğlu and Sarı, marks it as ‘vulnerable’. The FAO sheet says it is regularly found in markets in the Tyrrhenian Sea, Sicily and Türkiye. The Sea of Marmara is a different story: an assessment Bilecenoğlu published in Zootaxa in 2020 accepts that Artüz and Fricke provided convincing data in 2019 for removing the species from the Sea of Marmara list.