Cape D'Aguilar Marine Reserve — known in Chinese as 鶴咀海岸保護區, Hok Tsui Hoi Ngon Bou Wut Keui — occupies the far southeastern corner of Hong Kong Island, covering a stretch of rocky coastline mainly between Kau Pei Chau island and the shore. It was designated in July 1996 under the Marine Parks Ordinance, making it Hong Kong's only Marine Reserve — a designation distinct from the territory's Marine Parks in the strictness of its protections. Fishing, swimming, diving, and the collection of organisms are all strictly prohibited. Researchers must obtain a permit from the Agriculture, Fisheries and Conservation Department before conducting scientific work there. The reserve is managed by the AFCD in partnership with the Swire Institute of Marine Science, a research faculty of the University of Hong Kong that maintains a research facility on site.

The 1991 designation of Cape D'Aguilar as a Site of Special Scientific Interest came five years before the Marine Reserve was formally established. The rocky shores and subtidal habitats here are among the most ecologically significant in Hong Kong — sheltered enough to support rich intertidal communities of sea urchins, sea anemones, barnacles, and hundreds of invertebrate species, yet exposed enough at the headland to maintain the tidal flushing that keeps those communities healthy. The Swire Institute of Marine Science has operated here since the early 1990s, making the site one of the longer-running marine research stations in southern China. Its biodiversity centre is intended to eventually house not just the research collections but also the whale skeleton that has been displaying outdoors since 1991.

On 27 June 1991, the fin whale skeleton — 6.4 metres long, the bones of a juvenile male calf — was moved from the University of Hong Kong campus to its current location on the shores of Cape D'Aguilar, next to the newly established Swire Marine Laboratory. It had spent 35 years on display across different buildings on the HKU main campus before undergoing a year-long reconstruction. The skeleton was often mistaken for the remains of Hoi Wai, a famous female orca who performed at Ocean Park Hong Kong from 1979 to 1997 — a confusion the institute has worked to correct. Swims considers the skeleton an important symbol of marine conservation: a whale that fed refugees, whose bones became a teaching tool, whose story spans colonial Hong Kong, the refugee crisis of the 1950s, and the emerging conservation movement of the 1990s.

In September 2018, Typhoon Mangkhut — one of the strongest storms on record in southern China — struck Hong Kong with sustained winds that cracked the whale skeleton's ribs, dislodged the lower right jawbone, and blew the left hip bone away entirely. The Swire Institute organised the 'Restoring Hong Kong's Whale' campaign to raise funds for repair. The longer-term plan is more ambitious: move the original skeleton into the new biodiversity centre on site for preservation, and replace the outdoor display with a 3D-printed replica designed to withstand typhoons, salt spray, and the humidity of Hong Kong summers. The calf that died in a harbour in 1955, carved up in a refugee crisis, will eventually exist in two forms simultaneously — the real bones inside, and a printed copy standing on the rocks facing the South China Sea.