AssetID: 55786462
Headline: What a catch! Scientists discover new species of walking shark' off Papua New Guinea 'by accident'
Caption: BY MARK WORGAN Scientists have identified a new species of walking shark in the waters off Papua New Guinea - a catch that is incredibly rare now for an animal of this size. The metre-long shark was found during a night-time expedition led by researchers from the University of the Sunshine Coast (UniSC), who were studying endangered epaulette sharks in the shallow waters of Milne Bay. The newly identified species, officially named Hemiscyllium dudgeonae or Dudgeon's Walking Shark, is found only in a small area of south-eastern Papua New Guinea. “New shark species don’t come along that often, and it’s most definitely the first one named after me,” said a surprised Dr Christine Dudgeon of the University of the Sunshine Coast about the metre-long specimen she caught by hand and carefully guided back to the study boat. Walking sharks are known for their unusual ability to use all four fins to move across reef flats during low tide. They feed on invertebrates on the seabed and are not considered dangerous to humans. Researchers had travelled to the region to investigate the distribution and conservation status of epaulette sharks native to the tropical waters north of Australia. UniSC PhD student Jess Blakeway, the study's lead author, was the first member of the team to spot the unusual shark after it was brought aboard. “Straight away I recognised that the colour pattern was different from any of the other species I had worked with before,” Ms Blakeway said. “The first thing that stood out was the white dashes along its brown body. These dashes were quite different to the leopard-like spots we were expecting. “We put it in a tub with fresh seawater to give us time for measuring and blood and tissue sampling, and over the next two nights found another 11 individuals with the same patterning. “It wasn’t until genetic analysis of the samples back in Australia that we could confirm a new species. It’s exciting because this is the first new species described for the genus since 2013.” The species has been named in honour of Dr Dudgeon, an expert in shark genetics and ecology who has studied the group for more than 20 years. Locally, the shark is known as kadedekedewa, a name that loosely translates as "dog shark" or "lazy shark", reflecting its slow movement across the seabed. Researchers say the discovery has also raised concerns about the shark's long-term survival because of its limited distribution and the threats posed by habitat degradation, fishing activity and climate change. “We hope to collect more data on our next research trip in October to help the International Union for Conservation of Nature (IUCN) Red List assess the species as vulnerable or endangered with extinction,” Ms Blakeway said. The study involved diving, snorkelling and reef-walking surveys, with scientists carrying out 70 dedicated searches across 35 sites in 15 locations. The research also challenged previous assumptions about the distribution of walking shark species around New Guinea. “Previously, it was thought that each species had distinct habitat barriers such as rivers or deep water. Now we know that distributions in eastern PNG overlap, though species do not co-occur. “The new species is the 10th in the PNG epaulette genus (group of species). Five are already listed as threatened with extinction on the IUCN Red List under criterion B (which relates to their restricted geographic range) – a criterion that only applies to three percent of all sharks.” The research was supported by funding from Conservation International, the Australia Pacific Science Foundation, Shark Foundation and the VanDyson Marine Fund. The findings were published in the Journal of the Ocean Science Foundation.
Keywords: feature,photo,video,sharks,animals,seas
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