on top of other sharks. Reproduction The swell shark is oviparous, laying two green or amber flattened eggs at a time. Fertilization occurs internally. The egg cases become attached to kelp or the reef with tendrils. It has been suggested that the length of the tendrils depends on the amount of surf action the region is under. After producing the egg case, no parental care is provided. The egg case which contains the embryo is approximately – by –. The embryos will feed solely on yolk before they hatch. The gestation time depends on water temperature but is typically between 9–12 months. Pups have a double row of enlarged dermal denticles to help them exit the eggcase. After hatching, the pup is approximately 15 cm in length and is fully self-sufficient. Diet Swell sharks hunt at night for bony fish, molluscs, and crustaceans. They will eat prey that is dead or alive. They feed either by sucking prey into their mouth or by waiting motionless on the sea floor with their mouth open, waiting to encounter prey. Swell sharks have also been known to look for food in lobster traps. Defense When the shark feels threatened, it will bend its body into a U–shape, grab its tail fin with its mouth, and suck in water. Doing so causes the shark to enlarge in diameter and makes it much harder for predators to bite or dislodge. The swell shark is capable of swelling by using water or air, which is stored in the stomach until released. When letting air out, the swell shark makes a dog-like bark. Swell sharks are non-aggressive and are considered harmless to humans. Biofluorescence Swell shark biofluorescence was first reported in 2014. Researchers presented species-specific emission patterns, indicating that biofluorescence potentially functions in intraspecific communication and assists camouflage. The key fluorecent pigments in the swell shark and the chain catshark are a set of brominated kynurenine compounds that appear to be synthesized by the kynurenine pathway starting from 6-bromo-tryptophan. The biochemical origin of 6-bromo-tryptophan in these species is not known. Conservation status There are no fishery operations that target swell sharks, however, they are occasionally caught as bycatch in lobster and crab traps, gillnets, and trawls. Swell sharks are not typically consumed by humans due to the poor quality of meat. Swell sharks are common in public aquariums, in part due to their longevity in captivity. The