The gulf catshark (Asymbolus vincenti) is a small bottom-living catshark endemic to southern Australia, reaching about 61 cm (2 ft) and living on sand, gravel and rocky ground between roughly 27 and 650 m. It is chocolate to dusky brown above, scattered with small white spots, and plain cream below, with a narrow head and two equal dorsal fins placed well back.
It feeds on small bottom fishes, crustaceans, squid and worms, and lays paired egg cases anchored to weed and rock by long tendrils. Clutch size, growth rate and lifespan all remain unmeasured. The IUCN listed it as Least Concern in 2024. It is harmless to people and is taken only as occasional trawl bycatch.
- Maximum length61 cm (2 ft); most adults 40–55 cm
- WeightNo reliable measurement; well under 2 kg
- LifespanUnknown; no ageing study exists
- Depth range27–650 m (90–2,130 ft), mostly 100–250 m
- DietSmall bottom fish, crustaceans, squid and worms
- IUCN statusLeast Concern (assessed 2024)
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Chondrichthyes
- Order
- Carcharhiniformes
- Family
- Pentanchidae
- Genus
- Asymbolus
- Species
- Asymbolus vincenti
- Family (common)
- Deepwater catsharks
- Also known as
- Gulf St Vincent catshark, Spotted catshark
On this page
How to recognise a gulf catshark
Look for the spots. The back and sides are chocolate to dusky greyish brown, sometimes faintly mottled, and across that ground runs a dense scatter of small, crisp white flecks, each no bigger than a pinhead. The underside is plain pale cream with no markings at all. Gulf catsharks do not have the dark saddles, blotches or bars that decorate most other catsharks, and that combination of a plain brown back with fine white dots is the quickest field mark on the southern Australian shelf.
The body is slender and firm, tapering to a long low tail with a small lower lobe. The head is narrow, with a short rounded snout, and the eyes are distinctive: oval, set horizontally on the side of the head with a low ridge underneath and a rudimentary lower eyelid. Behind each eye sits a small spiracle. The two dorsal fins are nearly the same size and both are set far back, the first over the pelvic fins and the second over the anal fin.
Run a hand along the flank and the skin is rough in one direction only, the effect of the overlapping dermal denticles every shark carries. The mouth is small and set well under the snout, filled with rows of tiny teeth that each carry a central cusp with smaller points on either side. The impression is of a compact, firm little shark rather than the soft-bodied kind found deeper down.
How big does the gulf catshark get?
The largest measured gulf catshark is about 61 cm (2 ft) in total length. Most adults trawled off South Australia and Tasmania fall between 40 and 55 cm, so a typical animal is roughly the length of a forearm. Older accounts that give 55 cm as the maximum are slightly short.
No weights have been published for the species, which is normal for a small shark that has never had commercial value. On its proportions a 55 cm gulf catshark would be well under two kilograms, but that is an estimate from body shape rather than a measurement and should be treated as such.
Size at hatching, size at maturity and growth rate are all unrecorded. In other members of the genus Asymbolus, which are all small Australian endemics of similar build, hatchlings emerge at around 12 to 14 cm and adults mature at roughly three-quarters of maximum length, but no study has confirmed those figures for this species. The size bar below compares the 61 cm maximum with a diver, which puts the animal in proportion better than any number can.
Where gulf catsharks live
This shark is endemic to southern Australia and occurs nowhere else. Its range runs along the temperate southern shelf from southern Western Australia, across the Great Australian Bight, into South Australia, and east to Victoria, Tasmania and the far south of New South Wales. Gulf St Vincent, the sheltered gulf below Adelaide that gave the species its name, sits in the middle of it. The rest of the country's fauna is covered on our sharks of the Australian coast page.
The published depth range is 27 to 650 m, and most specimens come from between about 100 and 250 m on the outer shelf and the upper slope. The bottom there is sand, shell grit, gravel and low rocky reef, and the shark lives directly on it, resting between periods of slow foraging.
One detail from older accounts needs correcting. Gulf catsharks are sometimes described as living in the seagrass meadows of the Great Australian Bight. Seagrass in that region grows in clear shallow water, typically above 20 or 30 m, and the bulk of this species' records come from four to ten times deeper. A young gulf catshark may turn up on the shallow inshore edge of the range, but this is a shelf and upper-slope animal, and calling it a seagrass shark gives the wrong picture of both its habitat and the fisheries that meet it.
What gulf catsharks eat
No dedicated stomach-content study of Asymbolus vincenti has been published, so the diet described here rests on the shark's dentition, its habitat and the feeding of its close Australian relatives.
The teeth are small and multi-cusped, arranged in many closely packed rows, and the mouth itself opens on the underside of the head, well back from the tip of the snout. That is a bottom-feeder's arrangement: a shark built this way approaches prey from above and seizes it against the seabed. It cannot crush a thick shell and cannot shear a chunk from anything large. The prey that fits is small and soft or lightly armoured, which on the southern Australian shelf means small bottom fishes, prawns and other crustaceans, small squid and octopus, polychaete worms and whatever carrion drifts down.
The hunting itself is unhurried. A gulf catshark is a nocturnal, close-to-the-bottom forager that works the gaps between rocks and the shell grit with its snout, using smell and the ampullae of Lorenzini spread across its head to locate buried animals by the faint electric fields they give off. At 150 or 200 m there is not enough light to hunt visually, and the eyes serve mainly to detect movement and shadow.
A shark of this size on this bottom does not need to eat often, and long rests between feeding bouts are the rule across the genus.
Behaviour and daily life
Very little of this shark's behaviour has been watched directly, and the honest position is that most of what follows is drawn from the genus rather than from the species.
Gulf catsharks are benthic to the point of being sedentary. They spend the daylight hours lying still on sand or wedged under ledges and rock overhangs, and become active after dark. Movement is a slow, sinuous glide with the belly almost touching the bottom, powered by the whole body rather than by the small fins; there is no cruising in midwater and no long-distance migration on record.
Catsharks have no swim bladder and, unlike the deep-sea species, no great oil-filled liver to offset their weight, so a gulf catshark is negatively buoyant and simply sinks when it stops swimming. For an animal whose food is on the seabed that is an advantage, not a defect, and it is why these sharks hold station in current without effort. Spiracles behind the eyes let them pump water over the gills while lying motionless with the mouth in the sand.
Nothing suggests strong social structure. Trawl catches bring up single animals or a few together, which more likely reflects patchy food than schooling. Our shark anatomy page covers the spiracles and buoyancy mechanics in more detail.
Reproduction and lifespan
The gulf catshark is oviparous. Females produce eggs two at a time, one from each oviduct, sealed in a tough, amber, purse-shaped capsule. Each corner of the capsule carries long coiled tendrils, and the female works these around seaweed stems, sponges, sea whips or rock so that the case is anchored clear of the sediment where water can flow over it. Nothing is laid in the open mud, and there is no parental care after the case is fixed in place.
Inside, the embryo lives on its yolk alone. There is no placenta and no supplementary feeding by the mother, so everything the hatchling needs is packed into the egg on the day it is laid. When the yolk is used up the young shark cuts its way out fully formed and immediately independent, a miniature of the adult complete with the white spotting.
How many eggs a female lays in a season, how long incubation takes, and how large the hatchlings are have never been recorded for this species. In related Australian catsharks incubation runs to several months and lengthens in cold water, and females lay in batches through an extended season rather than all at once.
Lifespan is equally unmeasured: no vertebral ageing study exists. Small temperate catsharks that have been aged tend to live one to two decades and mature slowly, and there is no reason to expect the gulf catshark to differ much (see how long sharks live). Anyone quoting a precise age or litter size for this shark is borrowing it from another species.
Is the gulf catshark dangerous?
No. The SharkSider database holds no incident attributed to this species, and there is no record anywhere of a gulf catshark biting a person. The animal is a 50 cm bottom dweller with a small mouth set under its snout and teeth a few millimetres long, built for prawns and worms, and it lives mostly a hundred metres or more below the surface. The overlap with swimmers is close to nil.
Divers working the shallow inshore edge of the range in South Australia and Tasmania do occasionally find one resting under a ledge, and the shark's response is to lie still until approached and then swim away along the bottom. It has no fin spines, no venom and no defensive behaviour worth the name.
The only injuries associated with the species come from handling. A gulf catshark hauled up in a trawl or on a hook twists strongly, and the rough skin will take the top layer off a bare hand. Support the body, keep clear of the mouth, and return it to the water quickly; unlike deep-slope sharks, an animal from 100 to 200 m has a reasonable chance of surviving release.
The SharkSider database has no incident attributed to this species. The database draws on the International Shark Attack File, the Global Shark Attack File and verified local reports, and is updated weekly.
Conservation status
The IUCN assessed the gulf catshark as Least Concern in 2024. The species has no commercial value, is not targeted by any fishery, and occupies a broad stretch of the southern Australian shelf, much of it deeper than the main inshore fishing grounds.
The pressure that exists is trawl bycatch. The Great Australian Bight trawl sector and the South East Trawl fishery both work the depths this shark occupies, and gulf catsharks come up in the nets alongside the target flathead, whiting and prawns. They are discarded, and survival depends heavily on tow duration and depth: an animal from 100 m brought up in a short tow usually swims away, one from 400 m in a long tow often does not. Australian trawl fisheries operate under catch documentation and observer coverage, and much of the Bight is closed to trawling under marine park and benthic protection zoning, which keeps the incidental take modest.
What is genuinely missing is data. There is no population estimate for this species, no abundance trend, and no biological study of growth, maturity or fecundity, so the Least Concern rating rests on the absence of a known threat rather than on evidence of stability. That is a common position for small endemic sharks and a fragile one: a species with a range confined to a single country's shelf has nowhere else to retreat to if that shelf is fished harder (see why sharks are endangered and what the IUCN Red List categories mean). The gulf catshark is not listed on any CITES appendix.
Similar species and close relatives
The genus Asymbolus is an Australian speciality: roughly ten small spotted catsharks, all confined to the country's shelf and upper slope, and all so similar that several were separated only in the 1990s. The gulf catshark's nearest neighbours include the grey spotted catshark of the south-east and the orange-spotted catshark of the east coast, which differ in the colour and density of the spots and in fin proportions. A spotted Asymbolus identified from a photograph alone should be treated as provisional.
Among sharks with pages here, the closest comparisons are the other catsharks of temperate Australasia. The Australian swellshark shares the southern shelf and is caught in the same trawls, but is far bulkier, boldly blotched, and able to inflate itself with water; the draughtsboard shark of New Zealand is its close relative and carries a chequered pattern. Further north, the Australian marbled catshark is a slim inshore reef species with dark bars and spots.
Outside Australia, the species that most resembles the gulf catshark in build and habit is the small-spotted catshark of the north-east Atlantic, another sandy-bottom egg layer of about the same size, while the puffadder shyshark of South Africa and the quagga catshark of the western Indian Ocean fill the same niche on their own coasts with far bolder patterns.
- Australian Swellsharkspecies profile
- Draughtsboard Sharkspecies profile
- Australian Marbled Catsharkspecies profile
- Small-Spotted Catsharkspecies profile
Puffadder Shysharkspecies profile- Quagga Catsharkspecies profile
Frequently asked questions
How big does a gulf catshark get?
The maximum measured length is about 61 cm (2 ft), and most adults taken in southern Australian trawls are 40 to 55 cm. No weights have been published, but a full-grown animal is well under two kilograms. Hatchling size, size at maturity and growth rate have never been recorded for the species.
Where do gulf catsharks live?
Only in southern Australia. The range runs from southern Western Australia across the Great Australian Bight to South Australia, Victoria, Tasmania and far southern New South Wales. They live on sand, gravel and rocky bottom between 27 and 650 m, most commonly between about 100 and 250 m on the outer shelf and upper slope.
Why is it called the gulf catshark?
It is named for Gulf St Vincent, the sheltered gulf below Adelaide in South Australia where the species was first collected, which is also the source of the scientific name vincenti. The name is geographic rather than descriptive, and it has nothing to do with the Gulf of Mexico or any tropical gulf.
Do gulf catsharks live in seagrass?
Not really. Older accounts describe them living in seagrass in the Great Australian Bight, but seagrass there grows in clear water above about 30 m while most records of this shark come from four to ten times deeper. It is a shelf and upper-slope species living on sand, shell grit and low rocky reef.
What do gulf catsharks eat?
No stomach-content study exists for this species. Its small multi-cusped teeth and underslung mouth mark it as a bottom feeder, and the likely diet is small bottom fishes, prawns and other crustaceans, small squid and octopus, polychaete worms and carrion. It forages mainly at night, locating buried prey by smell and electroreception.
How do gulf catsharks reproduce?
They lay eggs, two at a time, one from each oviduct. Each amber capsule carries long tendrils at the corners which the female winds around seaweed, sponges or rock to anchor it. The embryo develops on its yolk alone and hatches fully formed. Egg number, incubation time and hatchling size are unrecorded.
Are gulf catsharks dangerous to humans?
No. There is no record anywhere of a gulf catshark biting anyone, and none in the SharkSider database. It is a half-metre bottom dweller with a small mouth and millimetre-long teeth, living mostly deeper than 100 m. It has no fin spines and no venom. Rough skin can graze a bare hand during careless handling.
How long do gulf catsharks live?
Nobody knows, because no vertebral ageing study has been carried out. Comparable small temperate catsharks that have been aged live for one to two decades and mature slowly. Any specific lifespan quoted for this species is borrowed from another shark, and the honest answer remains that it has never been measured.
Are gulf catsharks endangered?
The IUCN listed the species as Least Concern in 2024. It has no commercial value and no fishery targets it, though it is taken as bycatch in southern Australian trawls. There is no population estimate or trend, so the rating rests on the absence of a known threat. It is not on any CITES appendix.
References
A small team focused on researching sharks and making marine biology easy to understand. Every page is reviewed against current species records and the SharkSider attack database, and updated when new incidents or research appear.
Published November 9, 2022 · Last updated September 22, 2026 · No incident attributed to this species in the SharkSider attack database, which is updated weekly.
