The Agriculture, Fisheries and Conservation Department (AFCD) on Sunday said Hong Kong's coral reefs are generally healthy, although bleaching was observed during summer this year.

The department, along with the non-profit Reef Check Foundation, conducted its five-month review of local corals from June at 33 sites of ecological importance, which included nine marine parks.

It found that coral coverage at the sites ranged from 12.8 percent to 75.1 percent, with the highest coverage recorded at Hoi Ha Wan.

Eleven sites had more than 50 percent coral coverage, in which five of them were marine parks.

The average health index of corals across all sites was 3.95, which is above the general average of three.

But the AFCD said large-scale coral bleaching reappeared after it last occurred in 2022.

"The department has engaged a group of local coral and marine science experts to consult with and gather their views on conserving corals in Hong Kong, and to explore future directions of relevant research and conservation work, such as identification and enhancement of monitoring for the key environmental factors associated with coral bleaching as well as devising research projects for alleviating the impact of coral bleaching in the local environment," an AFCD spokesman said.

He said corals which saw the most bleaching were recovering due to the influx of cooler waters from last month.

The results also indicated there were no signs destructive fishing practices, but abandoned nets were found at 12 sites.

The department said the impact was low and the netting would be removed.