Discarded lobster pots, fishing nets and a car gearbox were among the items a team of 10 volunteer divers cleared out of the sea near the Palm Jumeirah's coastline yesterday.
Helen Sell, the marketing manager for Atlantis Dive School, said the Dive Against Debris event had resulted in "a big haul" of items that were harmful to the marine ecosystem.
"Fishermen throw down the nets and they get caught under the reclamation rocks at the edge of the Palm," she said. "They can't bring them up, so they leave them in the water." She said that 50 or more fish, including some large hammour, had been trapped in the nets and in the lobster pots.
The area off the coast of the Palm is part of an exclusion zone, where fishing is prohibited.
Fishing boats that venture into the zone are often warned off by coastguard vessels.
Ms Sell said the clean-up had yielded more debris than a previous event in January, when 12 people took part.
"Getting them to the surface is the easy part, what's hardest is trying to drag them onto the boat," said Jason Sockett, the general manager of the school.
Last year, the dive school held six such events but plans to increase this to one clean-up a month, partly because of the popularity of the events.
"It's a worthy cause, but the majority of people take part because it's also just a fun day out," said Mr Sockett.