Saving flower crabs for future generations

The crab house in Pendas Laut, Gelang Patah, Johor, was built to help increase the crab population in the area.

THE dwindling population of ketam renjong (flower crabs) in Gelang Patah has caught the attention of researchers from Universiti Malaysia Terengganu (UMT) to carry out a repopulation programme.

The team, led by UMT Marine Biotechnology Institute senior lecturer Dr Mohamad Nor Azra Md Adib, said the project started in 2020 after research showed a steep decline in crab population in the area.

“Johor used to be the main producer of flower crabs, with Gelang Patah as its main collecting point, based on data from Johor Fisheries Department.

“However, the department’s latest data reveals that only 1,500 tonnes were hauled in 2020, compared to 5,000 tonnes back in 2001.

“Overfishing and the unsustainable method of catching female flower crabs are among reasons for the drop in numbers,” he said when contacted.

He added that Gelang Patah — one of the breeding grounds for flower crabs in the country — was chosen due to its natural environment.

“To protect the population from further decline, we introduced an awareness campaign for locals and an ‘incubation room’ for crab farmers or fishermen in the area.

“The room is about 3m by 3m in size and can house about 30 female crabs at a time.

“So when fishermen catch female crabs bearing eggs, they place them in the incubation room, which floats over the water until they release their eggs, and then the crabs are returned to the sea.

“Female crabs need special attention during the spawning season as they can discard their eggs when threatened or under stress,” he said.

The cost of developing the incubation room was RM7,000, which was given as a grant from The Sustainable Ocean Alliance and the Environmental Defence Fund non-governmental organisation based in the US, said Nor Azra.

Nor Azra added that his team had met up with locals in Gelang Patah to educate them on ensuring the sustainability of the population by not consuming female crabs.

“There is also an ongoing trend of eating baby crabs.

“This is very bad for the environment as premature crabs are being targeted for consumption,” he said, adding that to stop this, his team started a buy-back programme from local fishermen.

Johor Fisheries Department director Zainudin Abd Wahab hoped to emulate the programme in other parts of the state if the outcome of the research was fruitful.

“We are in full support of the initiative and hope we can see an improvement in the next two years,” he added.