Proceedings of the Third World Fisheries Congress: Feeding the World with Fish in the Next Millenium—The Balance between Production and Environment

Back to the Future: A Paradigm Shift for Restoring Hong Kong’s Marine Ecosystem

Eny Anggraini Buchary, Wai Lung Cheung, Ussif Rashid Sumaila, Tony J. Pitcher


Pre-World War II fisheries in Hong Kong were artisanal. Local fishing vessels were mostly of traditional design and wind-powered (Naval Intelligence Division—UK 1944). During the occupation of Hong Kong by the Japanese in 1942–1945, fishing activities were greatly reduced from the prewar period. After the war, with the assistance of the Hong Kong government, the Hong Kong fisheries were reestablished (AFD 1950). Mechanization has occurred rapidly since then, resulting in a dramatic increase in fishing effort, particularly in the bottom-trawling sector (Gaiger 1974; Nichols 1974; Pitcher et al. 1998).

As a result of increasing fishing effort, the status of fishery resources has changed substantially over the past few decades. Although total landings in Hong Kong waters increased over the past 50 years, catch per unit effort (CPUE) dropped rapidly (Cheung 2001). In the first half of the 20th century, large pelagic and demersal predatory fish species (e.g., Serranidae, Lutjanidae, and Scombridae) were the major catch components (Cheung 2001; Herklots and Lin 1940). The abundance, biomass, and species diversity of fish and benthic organisms declined in the 1980s (Wu 1988). Recent catches are dominated by species characterized by small size and high growth rate, such as small pelagic fishes and invertebrates (Pitcher et al. 1998), and the amounts of previously abundant adults of large, predatory, high-value food fishes have declined markedly. Some of these species (e.g., red grouper Epinephelus akaara and giant croaker Bahaba taipingensis) are on the verge of local extinction (Sadovy 1998; Sadovy and Cheung 2003). Despite well-documented accounts of the serious physical impact of trawling activities on fragile benthic organisms such as corals, sponges, and gorgonians that are important for providing shelter and food for fishes (Leung and Lee 1987; Wu 1988; Gomez et al. 1990; Jones 1992; Morton 1996; Watling and Norse 1998), the bottom-trawling fishery continues in Hong Kong.

Ecological processes called Odum’s Ratchet (Pitcher 2001) that have compromised Hong Kong fisheries will likely continue to occur if current fishing patterns continue. In an Odum’s Ratchet scenario, which is intensified by government subsidies, fishing depletes the large long-lived species over generalist, k-selected species, leading to simpler ecosystems with higher volatility as well as lower value and trophic levels (Pitcher 2001; Pauly et al. 1998a; Pitcher and Pauly 1998). Large high-value species with specialized niches are rapidly lost (Christensen and Pauly 1998). Consequently, small fish begin to dominate landings—a process evident in Hong Kong—replacing large high-value fish. This ecological mechanism suggests that, unless the situation is mitigated, future disasters will occur at an increasing rate (Pauly et al. 1998b). Hence, fishery management that aims to restore fisheries and marine resources in Hong Kong is urgently needed.