Connie Watts was with family when she photographed the shark after she found it washed ashore at Lake Wollumboola, south of Culburra Beach in the afternoon.

Organisation for the Rescue and Research of Cetaceans in Australia (ORRCA) vice president Jools Farrell said the shark is likely to be either a grey nurse, or a lemon shark.

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Grey nurse sharks are typically more than three metres in length, and their teeth point outwards.

The population is listed as critically endangered, with around 1200 grey nurses left on the east coast, Ms Farrell said.

"These sharks are in very serious trouble," Ms Farrell said. "So it's a pretty sad sight to see."

Ms Farrell believed there could have been a number of possibilities that left the shark washed ashore.

"Whether it's was by-catch with commercial fishing and it was chucked over the side or caught in nets, or whether it was from a fisherman that's caught it," Ms Farrell said.

"Or it may have just died of natural causes."

Ms Farrell advised residents to stay away from the shark until it is collected from the shore.

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