Carcharhinidae spp.
Silky sharks are most commonly logged in New South Wales and the Galápagos. Spot them in water from 18-29 °C, with peak sightings March to May.
Silky sharks are named for the unusually smooth, almost silk-like texture of their skin, which you can appreciate even at distance by the sleek, streamlined look of the body. They are a mid-to-large requiem shark (family Carcharhinidae) with a slender, rounded snout, long pectoral fins, and a relatively small first dorsal fin set well back from the pectorals. Colouration is a warm bronze-grey on the back fading to a clean white underside, with no bold fin markings, the absence of obvious white or black fin tips is a key field clue. The trailing edge of the second dorsal fin is noticeably elongated, a good underwater pointer when the shark passes you side-on.
Silky sharks are typically encountered as free-swimming, open-water animals rather than reef-hugging species; divers most often see them cruising in the mid-water column, sometimes approaching out of the blue before circling at a distance. They are generally inquisitive rather than skittish, often making slow passes before moving off. At aggregation sites they can appear in loose groups, particularly around features that concentrate prey.
Silky sharks are one of the few requiem sharks known to associate with schools of tuna and other pelagic fish, meaning a diver who spots tuna activity in the blue water has a reasonable chance of finding silkies hunting at the edges.
In the Southern Hemisphere, where the bulk of sightings are recorded, encounters concentrate between March and May, autumn in Australia and the South Pacific. No strong Northern Hemisphere seasonal pattern emerges from current data.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
Most silky shark sightings are logged in New South Wales, Australia, which dominates the records by a wide margin, followed by sites along the Israeli coast near Caesarea. The Galápagos Islands in Ecuador round out the most reliable locations, offering open-water encounters in the cooler upwelling conditions typical of that archipelago. A smaller number of sightings come from West Sabah and Labuan in Malaysia and from Norfolk Island.
Mapping where Requiem Shark is logged…
The strongest concentration of logged sightings is along the New South Wales coast in Australia. Other reliable locations include Caesarea in Israel, the Galápagos Islands in Ecuador, and sites around Norfolk Island and West Sabah in Malaysia.
In the Southern Hemisphere, sightings cluster in March through May. If you are planning a trip to New South Wales or Norfolk Island specifically for silky sharks, that autumn window is your best bet based on current diver records.
Look for a slender, bronze-grey requiem shark with no bold fin markings, no prominent white or black tips. The first dorsal fin sits noticeably far back, the pectoral fins are long, and the skin has an unusually smooth appearance. The elongated trailing edge of the second dorsal fin is a useful pointer on a side-on pass.
Silky sharks are not considered dangerous to divers under normal conditions. They are inquisitive and may approach closely, but encounters are generally calm. Maintaining calm movement and avoiding erratic behaviour is standard practice with any requiem shark.
Diver observations place silky sharks in water ranging from roughly 18 °C to 29 °C, suggesting they can tolerate a fairly broad thermal range. They are regularly encountered in both the cooler upwellings of the Galápagos and the warmer subtropical waters off New South Wales.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Sandbar Shark
1,474 sites
