Oreochromis mossambicus (Peters)

Chan, Jeffery C. F., Tsang, Alphonse H. F., Yau, Sze-man, Hui, Tommy C. H., Lau, Anthony, Tan, Heok Hui, Low, Bi Wei, Dudgeon, David & Liew, Jia Huan, 2023, The non-native freshwater fishes of Hong Kong: diversity, distributions, and origins, Raffles Bulletin of Zoology 71, pp. 128-168 : 145-146

Oreochromis mossambicus (Peters)

( Fig. 34 , [LU])

Distribution. Plover Cove Reservoir ( Man & Hodgkiss, 1977 as Sarotherodon mossambicus ; Man & Hodgkiss,

1981 as Sarotherodon mossambicus ; Dudgeon, 1983 as Sarotherodon mossambicus ) Lamma Island area, Luk Keng area, Pui O area, Sham Chung area, Sha Lo Tung area ( Dudgeon & Chan, 1996 as Sarotherodon mossambicus ); Lok Ma Chau area, San Tin area (Environmental Resources Management Hong Kong Limited, 1999a as Sarotherodon mossambicus ); Lam Tei area (Environmental Resources Management Hong Kong Limited, 1999b as Sarotherodon mossambicus ); Pun Chun Yuen Stream, Lam Tsuen River ( Mott Connell Limited, 2000 as Sarotherodon mossambicus ); Tai Chung Hau area, Shuen Wan area, Lin Ma Hang Stream, Sandy Ridge Cemetery, Sha Ling area, Loi Tung area, Sheung Wo Hang, Tai Tong area, Cheung Po Stream, Wang Tong area, Sham Wat River ( Chan, 2001 as Sarotherodon mossambicus ); Tai O River (Ove Arup & Partners Hong Kong Limited, 2002 as Sarotherodon mossambicus ); Sha Ha Stream, Pak Kong River (Maunsell Consultants Asia Limited, 2004 as Sarotherodon mossambicus ); Sam Dip Tam Stream, Tso Kung Tam Stream (Mott Connell Limited, 2005 as Sarotherodon mossambicus ); Luk Tei Tong River (Maunsell Consultants Asia Limited, 2005a as Sarotherodon mossambicus ); Lam Tin area (Maunsell Consultants Asia Limited, 2005b as Sarotherodon mossambicus ); Siu Ma Shan area (Black & Veatch Hong Kong Limited, 2006 as Sarotherodon mossambicus ); Nam Long Shan area (within Ocean Park) (Maunsell Environmental Management Consultants Limited, 2006 as Sarotherodon mossambicus ); Kam Tin River (Black & Veatch Hong Kong Limited, 2005 as Sarotherodon mossambicus ; DSD, 2021; current survey); Man Uk Pin Stream (Black & Veatch Hong Kong Limited, 2007); Mai Po Nature Reserve (WWF, 2006; WWF, 2021); Wo Shang Wai area (Mott Connell Limited, 2008); Fung Lok Wai area ( CH 2M HILL Hong Kong Limited, 2008); Tsang Tsui area (Metcalf & Eddy Limited, 2008); Sha Lo Wan area, Pak Mong area (Ove Arup & Partners Hong Kong Limited, 2009); Big Wave Bay Stream ( DSD, 2010); Hok Tau Reservoir, Kowloon Reservoir, Pok Fu Lam Reservoir, Shek Lei Pui Reservoir, Tai Tam Tuk Reservoir ( Lai, 2011); Tei Lung Hau area (Ove Arup & Partners Hong Kong Limited, 2011); Kong Nga Po area (Mott MacDonald Hong Kong Limited, 2013); Fanling area, Kwu Tung area (Ove Arup & Partners Hong Kong Limited, 2013b); Cheung Chau Island (Atkins China Limited, 2013); Tai Sheung Tok area (Ove Arup & Partners Hong Kong Limited, 2014); Tseng Lan Shue area (Black & Veatch Hong Kong Limited, 2018); Nam Sang Wai area (Black & Veatch Hong Kong Limited, 2020a); Nam Wa Po area (DSD, 2020); Nai Chung Stream (AECOM Asia Company Limited, 2021b); Tai Po Kau Nature Reserve (AFCD, 2021c); Ma Wat River, Ping Yuen River, Ngong Ping Stream, Ma Tso Lung Stream, Tong Fuk River, Ho Chung River, Pak Ngan Heung Stream, Ngau Tam Mei River, Yuen Long Bypass Floodway, Deep Water Bay Stream, Ping Kong Stream, Cheung Po Stream, Wong Lung Hang Stream, Tai Tei Tong Stream, Shek Kong Stream, Sai Kung River, Fo Tan Nullah, Pui O Stream (DSD, 2021); Tai Po River, Lions Nature Education Centre, Kwu Tung Reservoir, Kwun Yam Shan Stream, Kowloon Reception Reservoir (GBIF.org, 2021); Tung Chung River ( Green Power, 2021); Waterfall Bay Stream, Sha Po area, Lau Shui Heung Reservoir, Tai Lam Chung Reservoir, Shing Mun Reservoir, Shap Long Irrigation Reservoir, Kai Tak River, Kowloon Byewash Reservoir, Kai Tak River; Ting Kok area (current survey).

Native range. Africa.

Remarks. First imported into Hong Kong as aquarium specimens during the 1940s, with further imports for the development of aquaculture in the 1950s ( Man, 1974). It has been released in various reservoirs around Hong Kong by the local government. It is presently abundant and widespread in polluted river channels in the New Territories. However, many localities where Oreochromis mossambicus was historically recorded (especially reservoirs) are now dominated by O. niloticus and Coptodon zillii . Oreochromis mossambicus differs from other members of the genus in that females and non-breeding males are silver-coloured with 2–5 mid-lateral black blotches and occasionally black dorsal bars; breeding males are all black except for a pale patch on the operculum, and red margins on the dorsal and caudal fins ( Trewavas, 1983).

Figures

Fig. 34. Oreochromis mossambicus, breeding males, Ting Kok area, photographed by Tommy C.H. Hui.