Atlantic Saury

Description

The Atlantic saury is an elongated slender fish with very long, beak-like jaws with minute teeth. The fish grow to about 35 cm (14 in) in length, with a maximum length of 50 cm (20 in). They have a row of finlets behind their dorsal and anal fins. They are similar in appearance to garfish but differ in having much smaller teeth. Atlantic sauries live near the surface, and will often jump above the surface.

Distribution and habitat

The Atlantic saury is native to the northern Atlantic Ocean, being present off the coast of North America, from the Gulf of Saint Lawrence to North Carolina and Bermuda, and off the coast of Western Europe. It has occasionally been recorded as far north as Iceland, Norway and Denmark, the British Isles and the Baltic Sea, its main range is further south in the Atlantic, the Mediterranean Sea including the Adriatic Sea and the Aegean Seas and the coast of Tunisia and Morocco. Its depth range is down to about 30 m (100 ft). When it was caught off the coast of Pembrokeshire in 1904, it was not recognised as a British fish, but with warming sea temperatures, it is expanding its range northwards.

Ecology

The fish are gregarious, feeding on zooplankton and fish larvae, and are hunted by tuna, marlin, bluefish and cod. It is a migratory fish, moving inshore during the summer and back out into deep water later in the year. Spawning takes place near the surface in the open sea. The eggs have filaments attached and are pelagic. The juveniles inhabit tropical mid-oceanic waters; their jaws are relatively short at first, but elongate as they grow.

Additional field notes

Atlantic saury are schooling surface fish that connect small planktonic prey with larger ocean predators.

Sources: Scomberesox saurus species summary

Schooling and predators

Large saury shoals sometimes approach the coast, although FishBase describes the species primarily as oceanic. This is a mobile fish of the upper water column, with the summary placing its usual recorded depth band within the upper 30 metres. A sudden inshore concentration is therefore only one part of its wider open-ocean life.

Fish eggs and small fish supplement the zooplankton and fish larvae in its diet. The predator list extends beyond tuna, marlin, bluefish, and cod to pollock, dolphins, and porpoises. Sauries may leap clear of the water while being chased. Surface jumping can consequently reflect predator avoidance, rather than a feeding or spawning event.

Sources: Scomberesox saurus species summary