New walking shark discovered in Papua New Guinea

Researchers have described a new-to-science species of walking shark, which lives in the remote, shallow waters off southeastern Papua New Guinea.

The newly named Dudgeon’s walking shark (Hemiscyllium dudgeonae) is a type of epaulette shark, a group of small sharks famous for their ability to use their fins to “walk” when stranded in tidal shallows. Walking sharks are nocturnal, feed on invertebrates and aren’t dangerous to humans.

Christine Dudgeon of the University of the Sunshine Coast in Australia and her colleagues were surveying the waters in and around Papua New Guinea’s Milne bay after midnight when she captured a meter-long fish by hand. Dudgeon told Mongabay by email that she initially thought she’d caught a Michael’s or Milne Bay walking shark (Hemiscyllium michaeli), also known as a leopard epaulette shark, “which was the one that we were looking for.”

Back on the boat and under light, Jess Blakeway, a PhD student at the university and the study’s lead author, noticed the shark’s color pattern was different from any of the walking sharks she had worked with before, according to a press release.

Although all walking sharks in the genus Hemiscyllium are similar in size and shape, species can be uniquely identified by their markings, Dudgeon told Mongabay.

Dudgeon added the Milne Bay walking shark has very distinctive leopard spots while the species she collected had white stripes and small brown spots all over it “and didn’t look like any of the other species at all.”

Over the next two days, Dudgeon said the team found 11 more individuals with this new pattern across three sites, including males and females, and immature and mature animals. It was then they were “quite convinced it was a new species,” she said.

They found the new sharks in shallow seagrass and on the top of coral sea mounts — habitats similar to those of the Milne Bay walking shark, Dudgeon said.

Genetic analysis confirmed the team’s hunch. “It’s exciting because this is the first new species described for the genus since 2013,” said Blakeway in the release.

Dudgeon’s walking shark, named in honor of Christine Dudgeon, becomes the tenth known species in the genus Hemiscyllium, a group native to shallow waters off Australia and New Guinea.

“It’s incredible that we are still finding new species in shallow waters like this, and highlights that there is more to find as long as we open our eyes and minds,” Dudgeon told Mongabay.

While the conservation status of Dudgeon’s walking shark is unknown, its restricted distribution may place it at risk.

“We are fortunate in working with local people in PNG and Milne Bay who are excited and proud of their endemic biodiversity, and we hope this work will raise the profile of the species and result in protections that support habitats and broader biodiversity,” Dudgeon said.

Banner image: Christine Dudgeon with the newly named walking shark. Image by Nesha Ichida.