Author: (Bonnaterre, 1788)
Flattened benthic sharks with dermal lobes on sides of head, symphyseal groove on chin, a rather somber, variegated colour pattern of dark back with obscure darker dorsal saddles and densely covered with prominent light 0-shaped spots; also, mouth in front of eyes, long, basally branched nasal barbels, nasoral grooves and circumnarial grooves, two rows of enlarged fanglike teeth in upper jaw and three in lower jaw, first dorsal origin over pelvic bases.
Head with 8 to 10 dermal lobes below and in front of eye on each side; nasal barbels with a few basal branches. No dermal tubercles or ridges on back. Origin of first dorsal fin about over last third of pelvic base; first dorsal height about equal to base length; interspace between dorsal fins longer than inner margin of first dorsal, about half length of dorsal base. Colour pattern variegated but more somber and less contrasting than most other wobbegongs except O. wardi, dorsal surface of body dark with somewhat obscure, broad, darker rectangular saddles with deeply corrugated margins separated by lighter areas, the entire dorsal surface densely spotted with large, 0-shaped, light markings; saddles not ocellate in appearance; interspaces between saddles without broad reticulated lines.
Western Pacific: Japan, South China Sea, Australia (Northern Territory, Western and South Australia, Queensland, New South Wales, Victoria).
Habitat and Biology:
An abundant, temperate to tropical, inshore bottom shark of the continental shelves of the western Pacific, occurring in the intertidal down to at least 110 m, commonly on coral and rocky reefs, under piers, and on sand bottom. It may occur in water barely deep enough to cover it, and has been seen climbing over ridges between tidepools, with its back out of water. It apparently is sluggish and inactive and is often found quiescent on the bottom, at least during the day when it is presumably resting. It is well camoflaged by its colour pattern and dermal flaps on rough bottom but is rather conspicuous on sand. This species (and wobbegongs in general) has not been studied to the extentof some nurse sharks (Ginglymostomatidae), but site specificity may be a feature of its behaviour like nurse sharks; anecdotal accounts suggest that individuals may return to the same site repeatedly. It is said to be nocturnal, and may swim and clamber about the bottom at night looking for food like nurse sharks. It is not known how important their camoflage Datterns are for feeding in this and other wobbegongs; it is uncertain if wobbegongs take a substantial amount of prey that simply blunders into proximity while they sit on the bottom, or if active prowling and stalking of prey at night is more important or their primary means of obtaining food. Wobbegongs in the Sydney area, presumably this common species, were observed to slowly sneak up to a bait at night from a considerable distance, as if stalking potential prey like a cat.
Ovoviviparous, with large numbers of young per litter; one female had 37. There are anecdotal accounts that male wobbegongs from the Sydney area (and presumably this species, which is abundant there) kept in aquaria fight vigorously among themselves while courting females, and that females are bitten by males in the gill region during courtship and one clasper is inserted; in captivity, these wobbegongs copulated in July. A wild male wobbegong was said to be attracted to a female kept in a wired enclosure open to the sea and tried to enter the enclosure during the breeding season; the implication is that the female gave off an attractive stimulus, presumably a chemical pheromone but possibly something else.
The spotted wobbegong feeds on bottom invertebrates, including crabs, lobsters and octopuses, and bony fishes including sea bass (Serranidae) and luderick (Kyphosidae). Prey items may blunder right up to the mouth of a lurking wobbegong, and even nibble on its tentacles, before being caught and devoured. Presumably the short broad mouth of this and other wobbegongs aids them in sucking in prey. The powerful jaws and big, modified anterior teeth in the symphyseal region of this and other wobbegongs, with one median and two lateral rows fanglike teeth in the lower jaw that interdigitate with two rows of lateral fangs in the upper jaw, form an effective traD to imPale and kill their prey.
Much has been made of the danger of this and other wobbegongs to people, often to the exclusion of much else of their life history. This species has been known to bite people that step on it or put their feet near its mouth, and can and will bite when molested or provoked, as when speared or caught by line or nets; these sharks can inflict severe lacerations, and one case was reported of a fisherman losing his foot to a spotted wobbegong that was disturbed by the person as it sat in a rock pool. At least for this species, fatal attacks arevirtually unknown. The strong jaws and jaw musculature, and (unlike nurse sharks) large and effective impaling teeth of these wobbegongs, coupled with their tendency to hold on after biting; makes them a minor hazard to unwary explorers of tide-pools, fishermen and divers, but the sharks otherwise appear to be relatively unaggresive and sluggish when unprovoked, as when a diver examines them underwater. However, placing one's limb near the head of a wobbegong may be inviting trouble, as the shark may attack either from misperceiving the limb as a smaller prey item, in response to being cornered by a possibly dangerous antagonist, or even in territorial defence. Several unprovoked attacks and a number of provoked attacks by Australian wobbegongs (probably including this species) on people, and even a few boat attacks, have been reported in the literature, but it is often difficult to determine which species was involved or what the precise circumstances were that Ied to the attack. Wobbegongs of all sizes, but especially larger individuals, should be regarded as potentially dangerous and should be treated with due respect.
Maximum total length about 320 cm, most individuals smaller, up to 150 to 180 cm. Adult males may mature at about 60 cm long. Size at birth about 21 cm.
Interest to Fisheries:
Limited, sometimes utilized for human consumption and for leather; the meat is apparently excellent eating and the skin of this and other wobbegongs is tough and makes an excellent, decorative leather with its handsome patterning. Spotted wobbegongs are commonly caught in trawls, beach seines, trammel nets, in lobster pots and traps, and with line gear. Some are taken by divers with spears. These sharks are regarded as a pest by lobster fishers, because they are adept at wedging themselves into lobster pots, to eat the catch and bait.
Extra-Australian records for this species require confirmation.
Holotype: Unknown. Type Locality: "La mer du sud".