A critically-endangered fish caused a stir when it was spotted in Abu Dhabi waters on Sunday.
The bowmouth guitarfish, a rare species of ray, was seen on Reem Island.
Residents flocked to the beach to see the fish, which is usually found lurking on the sea floor.
Marine experts at Environment Agency Abu Dhabi (EAD) caught the fish and carried out tests, before releasing it back into the water.
"We tried [using] the net initially and he swam straight out," said Winston Cowie, marine policy manager at the agency.
"So I just grabbed him and held him while Shamsa Al Hameli, our sharks and ray specialist, took DNA samples. The whole process took less than three minutes."
The fish has a wide body, a W-shaped mouth with rounded snout and large shark-like dorsal and tail fins. It has thorny ridges over its head and back.
The species can grow up to 2.7 metres in length, and can weigh as much as 135kg. It is also known by the names shark ray or mud skate.
It is considered critically endangered on the IUCN Red List.
On social media, residents of Reem Island shared photos and videos of the fish – which is almost 1.7m long – swimming close to the shore .
Omar Ibrahim, 13, from Egypt, who lives in a tower on the island, took a video.
"My friend Hussein and his dad were outside and saw it, so they called me. He lives four floors under me," he said.
"I instantly found it because there was a huge group of people and kayaks all around it.
"It didn't seem scared. It was actually really curious and close to the shore. It was a really nice experience."
Ms Al Hameli of EAD said the male fish was swimming close to the mangroves in an area with a ready supply of crustaceans, which he feeds on.
"We will continue to monitor him, to assess his behaviour over the coming days," she said.
Ms Al Hameli urged the public to keep a distance from the fish and avoid swimming next to it.
It has been a busy two months for EAD, which has been monitoring the presence of two whale sharks in Abu Dhabi.
On Thursday, authorities suspended marine traffic in waters near Aldar headquarters, in nearby Al Raha and Al Bahia further up the coast in a bid to protect the big fish.
The two whale sharks were originally spotted together in the Al Raha area seven weeks ago.
One has since moved on from Al Raha, but a smaller, juvenile shark remains in the area. EAD began supplementing its diet with krill supplied by the National Aquarium Abu Dhabi after noticing it had lost weight.
The larger adult whale shark is now swimming a few miles up the coast in Al Bahia.
Officials believe the pair followed a plankton bloom before becoming disorientated in channels in the area, leaving them unable to find their way out to open water.