The ornate wobbegong is a species of carpet shark popular for its unique structure and appearance. This shark is common in coral reefs and rocky areas with algae coverings. They inhabit the tropical waters of the Indo-Pacific Ocean from around Indonesia to the South of Australia including Papua New Guinea.
The ornate wobbegong is among the species of wobbegongs in the genus Orectolobus and family Orectolobidae. This species Orectolobus ornatus appears very flat with projections of flesh around its head. Also, they have this beautiful coloration with fine small spots. When considering the most uniquely decorated sharks, the ornate wobbegong would make the list.
As a typical wobbegong species, this shark possesses characteristics such as a preference for ocean bottoms, they are sluggish and nocturnal. However, there are several unique traits of the ornate wobbegong.
Scientific Description of the Ornate Wobbegong
The ornate wobbegong before the classification as a separate species was thought to be the young of the Gulf wobbegong (Orectolobus halei). Of certain, they share several similarities but still have noticeable differences.
The major differentiating factors between the two species include the fact that the adult ornate wobbegong is smaller than the Gulf wobbegong. Also, on closer observation, the ornate wobbegong has a smaller head to body ratio and has fewer spots on the body.
Another common name for the ornate wobbegong is banded wobbegong. But, on a more common note, this name applies more to the Gulf wobbegong.
How to Identify the Ornate Wobbegong
The ornate wobbegong is among the more common species of wobbegongs sharks. Encountering this species is likely common in areas where it occurs. There are factors to look out for when trying to identify this shark species. They include;
The dorsal side of the ornate wobbegong has a base brownish color with darker blotches of the same color covering the head, body, and tail. The ventral side (underbelly) is has a characteristic greenish-yellow color. This is the most distinguishing trait of the ornate wobbegong.
Considering the physical appearance, this shark species looks more like the spotted wobbegong (Orectolobus maculatus). However, the distinctive circular spots of the spotted wobbegong are not present on the ornate wobbegong. The spotted wobbegong is also larger than this species.
The body pattern of the ornate wobbegong has distinct black edges increasing their level of uniqueness. As this shark grows to an adult, the pattern tends to fade becoming less pronounced.
One advantage of the ornate wobbegong’s body pattern is its fit for camouflage. When this shark hides between rocks, or amid sea plants, it is very difficult to notice its presence. This is because the body pattern blends in with the surrounding environment.
Head, Mouth, and Eyes
The Ornate wobbegong has a smaller head when compared to body size. However, the head is generally large and flattened. This shark has small oval eyes. The mouth has several dermal lobes projecting outwards surrounding it. These lobes serve as a sensory organ and also helps to complete the shark’s camouflage.
This shark has two dorsal fins. The pectoral fins are large and spreads out as it lies flat on the bottom of the ocean. Also, the anal fin, pelvic fin, and caudal is present in this species.
The ornate wobbegong has long, sharp teeth with no lateral cusplets. This helps them as ambush predators to strike and grab their prey. In the upper jaw, there are two fang-like teeth, while the lower jaw contains three similar teeth.
A juvenile ornate wobbegong would measure just about 7.9 inches (20 cm) in length. However, they attain maturity at an average length of 2.6 feet (0.8 m). This shark species can grow up to 3.3 feet (1.0 m) as an adult. The maximum reported length of larger individuals is 3.9 feet (1.2 m).
Where to Find the Ornate Wobbegong
The ornate wobbegong occurs in tropical waters, coral reefs, bays, and rocky areas covered in algae. These environments give it perfect camouflage. They are shallow water dwellers mostly occurring from the water surface to a depth of up to 328 feet (100 m).
These sharks prefer to stay at the bottom of the ocean. When encountered, they usually lie without moving resting on the seafloor. Divers who swim to these habitats are likely to see this shark species.
The ornate wobbegong is native to the waters of eastern Australia. This location lies in the western area of the Pacific Ocean. There are confirmed reports of this shark also occurring in Sydney and Port Stephens. The reports of the existence of this species in Indonesia, Papua New Guinea, and Japan is still unclear. Therefore, making the ornate wobbegong indigenous to Australia.
Typical Behavior of the Ornate Wobbegong
The ornate wobbegong is a nocturnal species. As a result, this shark performs most of its activities during the night. Feeding and other movements take place when the sun has set. During the day, the ornate wobbegong would lie without moving on the bottom of the ocean inside caves, under ledges, or algae-covered seafloor. They stay in this state of sleep for most of the day.
Occasionally, the ornate wobbegong goes for light hunting during the daytime. They prefer to live in clearer water than other wobbegongs species such as the spotted wobbegong, which prefers murky waters.
This shark is a slow hunter that creeps in on its prey. They feed mostly on invertebrates, crustaceans, octopuses, and fish which includes mainly luderick, snappers, blackfish, and green moray eels. A study of the stomach content of an individual in Port Jackson shows that the mentioned fish make up a greater percentage of its diet. Cephalopods make up the remaining percentage.
The ornate wobbegong just like other wobbegong species also engages in ambush hunting of prey. They feed opportunistically on unsuspecting prey that gets too close to them while they are resting during the day. Their camouflage abilities help them to stay out of plain sight, hence prey may approach within strike range and used as a meal.
Life Cycle and Reproduction
An ornate wobbegong of length 2.6 feet (0.8 m) is already sexually matured. Not much is known about the mating of this shark species. The female shark is ovoviviparous. Gestation lasts up to a year. Parturition takes place within September and October. A litter usually contains over 12 pups.
The young ornate wobbegong is born fully developed. They have full teeth set which enables them to fend for themselves.
Predators of the Ornate Wobbegong
Any of the larger marine mammals may prey on this shark.
A common parasite of the ornate wobbegong is the Stragulorhynchus orectologi, a species of cestode found on the body of this shark.
Ornate Wobbegongs and Humans
The interaction between the ornate wobbegong and humans mostly lies in divers who swim to the bottom of the ocean. Therefore, considering the natural habitat of this species, they are unlikely to encounter humans. Here are ways in which the ornate wobbegong (Orectolobus ornatus) can interact with humans.
Danger to Humans
The ornate wobbegong is potentially dangerous toward humans. Under normal conditions, they would not attack anyone since they prefer to mind their business. However, when provoked, they are likely to bite and inflict painful injuries on the culprit.
Divers are most likely to be unexpectedly bitten by this shark species. This is because the ornate wobbegong camouflages so well that divers would not notice their presence and sometimes got bitten. This shark has been observed to at times approach divers with possible attack intent.
Attacks on Humans
According to the International Shark Attack File (ISAF), the ornate wobbegong is responsible for only one confirmed attack on humans. There are thirty-nine attacks attributed to wobbegong sharks in general with no species pointed out. The ornate wobbegong may still have a share in this.
The ornate wobbegong is not much of economic value. Although, the flesh is edible and the patterned skin used for decoration and in the making of leather. This shark is not usually a target of commercial fisheries; however, they are still caught both as target and bycatch.
The International Union for Conservation of Nature (IUCN) currently lists the ornate wobbegong (Orectolobus ornatus) as a “Least Concern (LC)” species. Before the current assessment, this species has been listed twice as Near Threatened (NT).
The only significant threat to the population of this shark species is the commercial fishing in its endemic zones. There are no information on the population trend and size of this shark. Therefore, it is not clear whether it is increasing or decreasing.
10 Interesting Facts of the Ornate Wobbegong (Orectolobus ornatus) at a Glance
1. The Ornate Wobbegong Was Once Thought to Be the Juvenile of the Gulf Wobbegong
The semblance of the ornate wobbegong and the Gulf wobbegong makes them share the same alternative common name “banded wobbegong”. The ornate wobbegong has a striking resemblance with the gulf wobbegong except that the former as an adult is notably smaller. Moreover, ornate wobbegong has a smaller head compared to body ratio.
2. This Shark is Slow and Sluggish
As a typical wobbegong species, the ornate wobbegong is mostly slow and inactive. Even during hunting for food, they prefer to creep in on their prey. However, they have been observed to occasionally engage in active pursuit of prey when in their most active state.
3. The Ornate Wobbegong is a Nocturnal Species
This shark performs most of its activities at nighttime. They engage in active feeding when it is dark and swim more at night than during the day. In fact, at daytime, the ornate wobbegong goes into a resting state. They hide inside caves, under ledges, in coral reefs, bays, or just sandy bottoms.
4. They Tropical Shallow Water Dwellers
The ornate wobbegong occurs in tropical waters of the western Pacific Ocean. They inhabit shallow depths ranging from 0 to 100 m. This shark species has its origin in the waters of eastern Australia.
5. Ornate Wobbegongs Have Beautiful Body Patterns
Just like the spotted wobbegong (Orectolobus maculatus), the ornate wobbegong has beautiful complex body patterns. However, unlike the spotted wobbegong, the ornate wobbegong does not have circular markings. Instead, it has unique marks with dark edges.
6. These Sharks Prefer a Meal of Luderick, Snappers, and Moray eels
The stomach content of an individual caught in Port Jackson upon inspection showed that luderick, snappers, and green moray eels made up 86.5% of the total content. Meanwhile, the remaining 13.5% consists of cephalopods.
7. The Ornate Wobbegong is an Ovoviviparous species
The females give birth to their young ones alive after the eggs hatch within their bodies. Gestation in this species lasts up to a year.
8. The Young are Born Fully Developed
From birth, the baby ornate wobbegong has the necessary adaptations for survival.
Their teeth come in full set helping them defend themselves.
9. Ornate Wobbegongs are Potentially Dangerous to Humans
The small sharp teeth of this shark can cause a shallow but painful injury once it bites. Though, the ornate wobbegong would rarely attack humans. They are most likely to attack when they feel threatened or they mistook the presence of a human to be prey.
10. There is Only One Confirmed Attack on Human by this Species
The International Shark Attack File (ISAF) recorded only one attack on humans confirmed to be by the ornate wobbegong (Orectolobus ornatus).
- “Discover Fishes: Orectolobus ornatus, Ornate Wobbegong”, Florida Museum of Natural History.
- “Banded Wobbegong, Orectolobus ornatus“, Australian Museum.
- “Ornate Wobbegong, Orectolobus ornatus)“, IUCN Red List of Threatened Species.
- “Orectolobus Ornatus, Ornate Wobbegong”, FishBase.
- “Ornate Wobbegong”, Wikipedia. (Assessed June 3, 2020)