The Ninepin Group has a high coverage of staghorn coral in the shallow waters and its steep rocky slopes are dominated by soft corals and a high diversity of octocoral and black coral species.
At least 120 fish species have been recorded, of which 29 are locally rare or endangered, such as Hong Kong
grouper. The islands are an important site for breeding terns. In 2015, AFCD established a no-anchoring area at
the northern side of South Ninepin to prevent coral damage. In 2009, the Country and Marine Park Board
produced a 324.5 hectare draft map of Ninepin Marine Park. It is also part of the UNESCO Global Geopark.

For decades, East Ninepin is used by the Civil Engineering and Development Department for open sea disposal of dredged sediment and uncontaminated mud, affecting sediment loads in the water. The government has no plans to cease this. A high-level of fishing by commercial and recreational fishers (e.g. hand-line, gill-netting, cage trapping, spearfishing) and illegal fishing has been recorded, resulting in a high occurrence of ghost nets. This area is frequented by divers. Several cases of disturbance to tern nests and eggs have been recorded, but increased site patrols and efforts to promote awareness has led to improvements.

● Designate Ninepin Group and its surrounding waters as a marine park. This is crucial to enhancing its resilience against climate change and facilitating the recovery of fisheries resources.
●  Only allow commercial fishing with a license, prohibit non-selective fishing methods (e.g. trammel nets and snake cages).
●  Regulate recreational activities (e.g. scuba diving) through licensing.
●  Set up patrol stations (e.g. on a floating platform) and work with fishing communities to combat illegal fishing.
●  Strengthen the notification mechanism of joint enforcement against
illegal fishing and trawlers from the mainland (e.g. an Automatic Identification System) to enhance execution of the Framework Agreement on Guangdong/ Hong Kong Co-operation.