Banded houndshark - Triakis scyllium

The banded houndshark Triakis scyllium is a moderately slender houndshark with a short, broadly rounded head, long labial furrows and comparatively narrow fins. It stays much smaller than many oceanic sharks but can reach about 1.5 metres in total length.

Young animals show broad dark saddles and small black spots on a grey to brownish background. This pattern may fade in adults, but the combination of rounded head, juvenile banding and bottom-living behaviour still makes the species distinctive.

Teeth, fins and body form

According to the FAO species catalogue, the teeth have strong main cusps and smaller lateral cusplets; farther back in the jaw they can become more blade-like. The body is built for manoeuvrable hunting over sand, algae beds and seagrass rather than for fast open-ocean cruising.

The banded houndshark Triakis scyllium is a moderately slender houndshark with a short, broadly rounded head, long labial furrows and comparatively narrow fins. It stays much smaller than many oceanic sharks but can reach about 1.5 metres in total length.

Young animals show broad dark saddles and small black spots on a grey to brownish background. This pattern may fade in adults, but the combination of rounded head, juvenile banding and bottom-living behaviour still makes the species distinctive.

Teeth, fins and body form

According to the FAO species catalogue, the teeth have strong main cusps and smaller lateral cusplets; farther back in the jaw they can become more blade-like. The body is built for manoeuvrable hunting over sand, algae beds and seagrass rather than for fast open-ocean cruising.

The banded houndshark Triakis scyllium is a moderately slender houndshark with a short, broadly rounded head, long labial furrows and comparatively narrow fins. It stays much smaller than many oceanic sharks but can reach about 1.5 metres in total length.

Young animals show broad dark saddles and small black spots on a grey to brownish background. This pattern may fade in adults, but the combination of rounded head, juvenile banding and bottom-living behaviour still makes the species distinctive.

Teeth, fins and body form

According to the FAO species catalogue, the teeth have strong main cusps and smaller lateral cusplets; farther back in the jaw they can become more blade-like. The body is built for manoeuvrable hunting over sand, algae beds and seagrass rather than for fast open-ocean cruising.

The banded houndshark lives in the northwestern Pacific. Its core range extends from the cooler coasts of the southern Russian Far East through Japan and Korea to eastern China and Taiwan; older records from the Philippines are regarded as uncertain.

FishBase lists the species as marine, brackish-tolerant, demersal and subtropical. It is associated with continental and island shelves, especially coastal shallows, bays and estuaries.

Coastal bottom habitats

The species keeps on or close to the seabed. Sand flats, algae-covered bottoms and seagrass areas are typical habitats, and shallow bays or estuaries can also be used when salinity, food and shelter are suitable.

Banded houndsharks are mainly bottom-oriented predators. They usually move as searching coastal sharks rather than as wide-ranging oceanic hunters, but several animals can gather where resting sites or food conditions are favourable.

The diet consists chiefly of small fishes, crustaceans and other benthic invertebrates, as summarised by FishBase. Their teeth are suited to a mixed diet of mobile and bottom-living prey.

Reproduction

The species is aplacental viviparous: embryos develop inside the mother and are nourished by their yolk supply rather than by a placenta. The FAO catalogue gives usually 10 to 20 young per litter. This slow life history makes regular removal of adults in coastal fisheries a serious pressure.

The banded houndshark is listed as Endangered by the IUCN Red List. The concern is sustained fishing pressure across heavily used coastal seas, not one isolated impact.

Main threats

• Bycatch and landings: the species is taken in trawls, set nets, gillnets and other coastal fisheries.
• Use as food fish: the meat can be used, even if older FAO notes describe it as less valued than related houndsharks in Japan.
• Coastal habitat pressure: estuaries, seagrass beds, shallow bays and algae grounds are productive but often stressed by development, pollution and fishing.

Effective protection depends on better species-level fishery records, lower bycatch, protection of productive coastal habitats and regional rules that also cover smaller coastal sharks.

The banded houndshark is not dangerous to people. It is a bottom-living hunter of smaller prey and is generally cautious or calm in observations and aquarium settings.

For divers, the species is interesting because it shows how varied sharks are beyond the large pelagic icons: a coastal shark with striking juvenile markings, brackish tolerance and a close ecological link to shallow shelf habitats.

Aquariums and observation

The current featured image shows an animal from Himeji City Aquarium and is documented through Wikimedia Commons. The species is comparatively familiar in East Asian public aquariums, but wild populations remain affected by fisheries.