OMAN BULLHEAD SHARK
The Oman Bullhead shark, (Heterodontus omanensis), is a Bullhead shark belonging to the family Heterodontidae found in the tropical western Indian Ocean around central Oman. This shark was described by Baldwin in 2005, making it one of the most recently described of its genus. It is distinguishable from its 4-5 broad saddles and unique egg cases.
Family: Heterodontidae- Bullhead Sharks
Common Name– Bullhead Sharks
Common Name– Bullhead Sharks
Status: IUCN Red List DATA DEFICIENT
Average Size and Length: Mature males have been measured at 52 cm/ 1.7 feet and mature females at 61 cm/ 2 feet. It is more than likely smaller in size than the Japanese Bullhead shark.
Teeth and Jaw: More than likely, they have small front teeth that are pointy and sharp for grabbing prey and side bottom teeth that are flat, perfect for cracking and grinding shells.
Head: They have a large blunt head, pig-like snout. There are two small spiracles behind the eyes. The nostrils are attached to the mouth.
Tail: The caudal fin is asymmetrical.
Demographic, Distribution, Habitat, Environment and Range: The Oman Bullhead shark is endemic to Oman in the northern Indian Ocean. May also be found in Pakistan and Masirah Island. They are presumably found over the continental shelf on soft bottoms at around 263 feet. This is seemingly true because specimens were caught as bycatch there. They are demersal and prefer tropical climates.
Diet: Their diet is more than likely similar to that of its family members.
Ram-Suction Index: Like the other members of its family, the Oman Bullhead shark is more than likely high on the suction side of the index. They more than likely suck in prey and water from rocks and crevices and use their unique different teeth to pierce the prey with its sharp front teeth when the jaw extends, and crush and grind it with its molar like back teeth.
Aesthetic Identification: The Oman Bullhead shark is tan to brown with 4 or 5 broad dark brown saddles (versus 11-14). There is a dark bar between the eyes and a blotch under the eyes. There are no spots on the body. The fins are dark-tipped with a white spot on the dorsal fin tips. The neonate color pattern is unknown. There are two dorsal fins with short spines preceding the fin. The origin of the first dorsal fin is over the pectoral fin inner margins. The pectoral fins are large and angular angled to the rear somewhat looking like paddles. The Oman Bullhead shark is distinguishable from the Japanese Bullhead shark by its color pattern and the very low dorsal fins. The first dorsal fin is much smaller than other members of its family (9.3-10.9% TL vs. 11-21% TL). An anal fin is present.
Biology and Reproduction: Not much is known of the biology or reproduction of the Oman Bullhead shark. They are presumably oviparous. The egg case is auger shaped and is unique having 2 long tendrils extending from its base and flanges with 2 turns. Others typically have 3 turns and short tendrils. This shape enables them to be wedged into rock crevices, and kelp for protection from predators. When the egg cases are soft, they are lighter in color. When they harden, they become a much darker caramel brown color.
Behavioral Traits, Sensing and Intelligence: Their behavior is poorly known, but more than likely the Oman Bullhead shark may have some similar behavioral traits as other members of their family. Which would be that they are nocturnal.
Speed: More than likely, they are poor swimmers, sluggish and slow moving just as the other members of their family are. The more than likely use their large pectoral fins to help it walk across the seabed and rocky surfaces and hold on to the rocks when hanging vertically. They probably have the ability to rest motionless on the bottom, while eating and breathing at the same time, like the other members of its family.
Oman Bullhead Shark Future and Conservation: Not much is known to evaluate the Oman Bullhead shark, but they may be at risk due to its limited range and its tendency to be caught as bycatch.
Oman Bullhead Shark Recorded Attacks on Humans: Harmless to humans (unless stressed), the Oman Bullhead shark poses no threat. Their spines can impose a painful wound if not careful.
Baldwin, Z.H., 2005, May 9. “A new species of bullhead shark, genus Heterodontus (Heterodontiformes: Heterodontidae), from Oman”. Copeia Vol. 2005, No. 2. pp. 262-264.