Hong Kong will draw up its own "red list" of plant and animal species in need of preservation.
Modelled on the global red list maintained by the International Union for Conservation of Nature, a preliminary draft is due in September.
It is part of the government's efforts to fulfil its responsibilities under the Convention on Biological Diversity that was extended to the city by Beijing in 2011.
The mainland already has its own regional red list.
Hong Kong's most celebrated endangered species is the Chinese white dolphin.
But the list may also take in species that are abundant in Hong Kong but scarce elsewhere, such as freshwater fish Parazacco spilurus, which is regarded as vulnerable on the mainland.
Plans for the list were outlined at a meeting of the Biodiversity Strategy and Action Plan Steering Committee, which was established by the government to come up with an action plan to guide conservation in the five years from 2020.
The global red list covers 71,576 species, including mammals, amphibians, birds, reef-building corals and conifers.
Making a Hong Kong list will help identify species of conservation concern, so that protection and management measures can be targeted towards priority species, the committee heard.
It will also guide future study and monitoring. After the local list is completed, experts will identify species for conservation after checking it against the global and regional lists.
The Convention on Biological Diversity is an international treaty on conservation of biological diversity, sustainable use of its components and fair sharing of the benefits.
The government is working on an action plan to fulfil the convention's requirements. A public consultation will be held next year.
More than 2,100 native plants, 997 marine fisheries, 520 birds, 236 butterflies and 55 terrestrial mammals are found in Hong Kong.