James Marino
In the sunlit waters of the upper ocean, most sharks are easily recognizable; sleek, grey-bodied, and familiar icons of pop culture and marine biology alike. But below the surface, in deep water where sunlight can’t reach, some sharks have evolved to look truly bizarre. The goblin shark is one such example. Gaunt, wrinkly, and pale pink, this lazy, slow-swimming beast is abnormally large for deep-sea fish, which tend to be smaller than their upper ocean cousins. The most distinguishing feature of the goblin shark, however, is its face. Instead of waiting for prey to come to its mouth, the goblin shark moves its mouth to the prey. It has a jaw that can detach from the rest of its face and shoot forward, capturing surprised prey, and also giving the shark a downright ghastly facial expression—goblin-like, in fact. Sounds frightening? This deep-sea goblin is only ever encountered by people who accidentally catch it in especially deep-sea fishing nets. So unless you’re a fish, worry not.
Apart from their namesake jaw party trick, little was known about goblin sharks until very recently. Scientists didn’t even know how long they lived, or how large they grew. This was worrying to many scientists. As human beings expand our capabilities of commercial fishing, we are beginning to venture into deeper and deeper water. This has the potential to put deep-sea marine organisms at risk of overfishing, but it’s impossible to know how much counts as overfishing if you don’t know much about a species—for example, how long they live, and how many of them there are in the population.
A team of researchers based out of San José State University recently published findings that help solve this problem for the goblin shark. They used blue dye to stain the tissues of a goblin shark’s soft backbone (the shark was a preserved specimen taken from when it was accidentally captured in a fishing net) and better view the ring-like patterns that formed in the backbone as the shark grew. Using this, they used a mathematical model to determine how old the shark was, and compared it to the shark’s size to determine information about how the goblin sharks develop throughout their lives. They discovered that goblin sharks grow to around 12 feet long, but grow slowly. They are not mature or able to reproduce until late in their lives, and they continue growing after they’re sexually mature. This means that the goblin shark population is vulnerable to human threats—if a goblin shark is killed, it takes years for another to take its place in the population because they grow and reproduce so slowly. This is really useful information to have, even though goblin sharks aren’t currently endangered. Knowing this means we can prevent them from becoming endangered in the first place! Even though they have frightful faces, these unique, quirky goblins are worth protecting.
Caltabellotta , F. P., Siders, Z. A., Cailliet, G. M., Motta, F. P., & Fazzano Gadig, O. B. (2020, August). Preliminary age and growth of the deep-water goblin shark Mitsukurina owstoni (Jordan 1898). ResearchGate.
https://www.researchgate.net/publication/343762009_Preliminary_age_and_growth_of_the_deep-water_goblin_shark_Mitsukurina_owstoni_Jordan_1898
Full-body photograph of goblin shark. (2016b). EarthTouch News Network. Retrieved October 2023, from https://www.earthtouchnews.com/natural-world/how-it-works/the-goblin-sharks-slingshot-jaws-are-the-fastest-of-any-shark-species/.
GIF of goblin shark extending its jaw. (2016c). EarthTouch News Network. Retrieved October 2023, from https://www.earthtouchnews.com/natural-world/how-it-works/the-goblin-sharks-slingshot-jaws-are-the-fastest-of-any-shark-species/.