Overview
The Pajama Shark (Poroderma africanum), celebrated across South Africa as the Striped Catshark, is one of the most uniquely patterned, charismatic, and famous inshore catsharks on Earth. Confined exclusively to the wave-swept rocky reefs and mystical kelp forests of South Africa’s southern cape, this handsome, docile bottom-dweller looks as though it is dressed in tailored striped sleepwear. Featured prominently in award-winning nature documentaries like ‘My Octopus Teacher’, it is a world-renowned ambassador of the Great African Seaforest.
Biology and Physical Characteristics
Poroderma africanum possesses an unmistakable, striking body pattern. Its cylindrical, robust body is covered in smooth, tooth-like dermal denticles, colored a pale greyish-cream to silvery-white and overlaid with five to seven thick, bold, jet-black longitudinal racing stripes that run unbroken from its snout to its tail. Its head is broad and flattened with a short, blunt snout, featuring a pair of short, sensory nasal barbels that hang before its mouth to help locate buried prey. Its eyes are oval, slit-pupiled, and set high on its head, shielded by thick eyelid folds. The dorsal fins are set remarkably far back along its muscular body, an adaptation that allows the shark to maneuver and coil through tight crevices, sea caves, and tangled kelp holdfasts without getting snagged.
Behavior and Ecology
Strictly nocturnal and sluggish during the daylight hours, the Pajama Shark spends sunny days resting motionless in communal slumber groups inside dark underwater caves, rock crevices, or beneath massive kelp canopies, often piled on top of other catsharks. When darkness falls, it transforms into an active, methodical benthic stalker, crawling through rocky gullies to hunt crabs, mantis shrimp, and sleeping octopuses. When threatened by broadnose sevengill sharks or Cape fur seals, it exhibits a bizarre defensive posture: it curls its body into an immovable, tight spiral circle, burying its head beneath its muscular tail to protect its soft belly and eyes with its armored, striped back. Females produce pairs of tough, rectangular, purse-like egg cases (‘mermaid’s purses’) with long, curled tendrils that anchor securely to kelp fronds.
Conservation and Human Impact
The Pajama Shark is classified as Least Concern on the IUCN Red List. It maintains high local population densities and is completely protected within South Africa’s network of Marine Protected Areas, including Table Mountain National Park Marine Protected Area. Because it is completely harmless to humans and not commercially marketed for food, it faces little commercial fishing pressure, though individuals are occasionally caught as accidental bycatch by coastal recreational shore anglers or entangled in commercial rock lobster traps.
Interesting Factoid
When threatened by a predator, the Pajama Shark curls itself into a tight, immovable donut shape and covers its face with its tail, using its striped back armor like a shield until the predator gives up and swims away!