Native to Australia, the Wobbegong (pronounced WO-BUH-GONG) is a bottom-dwelling shark, well adept in the art of camouflage; and for divers, a challenging spot on the floors of the Western Pacific and Eastern Indian Ocean, Japan and the South China Sea.
Two marine mavericks, Tom Brown and Fernanda Cortina ventured into the shallow reefs of Papua and captured the photography for this Wobbegong feature.
A great big bushy beard!
The name, 'Wobbegong' is thought to mean ‘living rock’, referring to the carpet shark's ability to blend with the rocky ocean floor. It’s also said that Wobbegong is the Aboriginal word for ‘shaggy beard’. With fleshy tabs found around its mouth and chin - this itself resembling "a great big bushy beard!"
Read about the adaptive features of the Wobbegong Carpet Shark:
Three Cool Wobbegong Features to Know...
How and what do wobbegong hunt?
In short, the Wobbegong sleeps all day (nocturnal) and eats lobster all night (aren’t they lucky!) The Wobbegong’s low-exertion hunting style is cunning; disguising itself as the ocean floor and playing the role of the ‘ambush predator’. It camps out amongst the sea beds, waiting for the next meal to swim across its path.
The Wobbie is a shark of sophistication, with an appetite for the finer things and a penchant for pricey crustaceans; often eating lobsters and smaller invertebrates. Its sharp teeth pack a punch, so it has no problems getting stuck into a hearty portion of crab. It looks like meat's back on the menu boys.
The carpet shark will wait for its prey to wander unknowingly through its territory, grabbing it with one quick lunge and oftentimes, swallowing prey whole.
Their ability to swallow prey whole is a result of their strong suction capacity and are able to dislocate their jaws to allow for more food to enter. Ouch! Fear not, they only cases of Wobbegong biting humans is; when trod on, provoked or disturbed, so keep your distance and admire with respect.
Its teeth are incredibly sharp so it has no problems when getting stuck into a hearty portion of crab. Moral of the story - don’t take a Wobbegong to dinner, it’ll cost you an arm and a leg (not literally - Wobbegong prefer the lobster).
Whilst the Wobbegong resembles a carpet - this shark is not one to be walked over, even by creatures with a hard shell exterior.
Adapting to sandier waters and Wobbegong breathing mechanisms
Wobbegong sharks are ‘dorso-ventrally flattened’ meaning their body’s are compressed along the dorsal (back) and ventral (belly) sides, making the body appear wider and slimmer from top to bottom.
Their narrow shape allows for demure, swift movement when finding new spaces to rest, hunt, and evade larger sharks and marine predators. Using their small pointed fins to scale the sea beds and their head spiracles (respiratory holes) to breath through sandier waters, the Wobbegong is highly skilled in the art of ground-dwelling.
The spiracles located at the top of the head in a crescent-shape behind the eyes, prevent the Wobbegong from inhaling sand and ocean particulates. How do spiracles work? It stops the Wobbegong’s need to use its mouth to inhale. This form of respiration is common to most sharks, excluding a few such as the hammerhead and requiem sharks, reducing damage to delicate gill tissue.
Love on the Ocean Floor
Wobbegong mating rituals outside of captivity are a thing of mystery, whereas protected male Wobbies are documented to be fiercely competitive when seeking courtship with a female.
During mating season (July in captivity, unknown outside of captivity), female Wobbegong release pheromones into the water to attract potential partners. Upon copulation, the male bites the female near to the gills (kinky!) and uses his clasper (pelvic fin) to reproduce with his chosen female.
Once pregnant, female Wobbegong will have a gestation period of up to one year in most cases, giving birth to 20-37 pups. This shark is ‘ovoviviparous’, meaning that they produce eggs that hatch inside of their bodies, to later give birth to living self-sufficient pups. Almost like giving birth twice - (no thank you!)
The difference between viviparous and ovoviviparous is that viviparity relies on an internal embryonic development and offspring dependency, whereas ovoviviparity means that the female lays an egg internally, giving birth to live infants and later producing self-sufficient young. (Different to Oviparous means to lay an egg externally)
Now we’ve discussed food, mating, reproduction, hunting and adaptivity of the Wobbegong, let’s visit the serious side of Wobbegong challenges. Whilst not rated as endangered, it’s important to note some of the issues affecting the population that could pose a serious threat into the future.
The impacts of coral bleaching
Whilst the shark isn’t in immediate threat and populations remain high, it’s important to consider the impact overfishing could have upon the Wobbegong population.
A lot of Wobbegong rely on ocean floors being caked in coral reefs, to help them camouflage, ambush, rest and reproduce. With coral bleaching becoming ever-more prevalent across shallow waters in which Wobbegong reside, habitat loss and destruction is a significant threat, caused by climate change.
Overfishing and bycatch
To humans, wobbegong is often the fish within the fish and chips, being overfished recreationally and commercially, sometimes by mistake. They are usually bycatch, crawling into lobster traps and as docile sharks, kept as a bonus dish.
If Wobbegong meat continues to be eaten at its current rate, the population of this particular carpet-shark could be in great peril. Despite the Wobbie having a number of larger fish and aquatic creatures above it on the food chain, Humans still remain to be the biggest threat to Wobbegong.
The Cool Animal Blog: I'd like to say a personal Wibbly Wobbly Gongy Wongy thank you to the brilliant Marine Expert and Blogger, Tom Brown and Wildlife Journalist and Photographer (and Marine Expert) Fernanda Cortina for sharing their amazing photographs with me after spotting a Wobbie in Papua.
You are two splendid bambinos and I will now be providing a life-time supply of chocolate hobnobs as a token of my never-ending gratitude and will follow you into the fires of Mordor.
Also a special shout out to free diver Sam Martin (aka Seaweed Sam) for allowing me to use his video of the spotted wobbegong! Always in awe at your photos and videos my friend from down under!
If you liked this article, be sure to check out the rest of The Cool Animal Blog, where we share interesting facts and stories about animals around the planet.
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