Introduction and use of non-native species for aquaculture in China: status, risks and management solutions


  • Yaping Lin,

    1. Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
    2. University of Chinese Academy of Sciences, Beijing, China
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  • Zexia Gao,

    1. College of Fisheries, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, China
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  • Aibin Zhan

    Corresponding author
    1. Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
    • Correspondence

      Prof. Aibin Zhan, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China. Email:

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Aquaculture is one of the fast-growing industries in the past decades. The fast expansion of aquaculture largely relies on the introduction and use of non-native species. This forms a paradox: some species significantly contribute to the fast expansion of aquaculture, while negative effects associated with unregulated introduction and irresponsible use of non-native species are increasing in number and area affected. However, lessons from reported disasters are slowly learned, and risks raised have been highly overlooked. Here, we discuss the known and potential risks derived from the introduction and use of non-native species in China to urge the necessity of incorporating sound management into sustainable aquaculture. Sound management needs to be performed based on the characteristics of each aquaculture activity or related event. We discuss risks based on aquaculture activities or related events popularly employed in the past decades in China, including (i) transfers of non-native species; (ii) fellow travellers, accidental introductions; (iii) artificial hybridization; and (iv) mass release of non-native species for ranching. For each aquaculture activity or related event, we provide general background, status of this activity, risks raised and recommendations for management. Finally, we call for the collaboration of researchers from academia, government and aquaculture industry for proper risk assessment and sound management for sustainable development of aquaculture.


Aquaculture is the fast-growing section of world primary industry in the past decades (Food & Agriculture Organization of the United Nations (FAO) 2012). In 2010, global aquaculture production reached more than 83 million tons and a value of US$ 136 million, which are six and ten times more than those 25 years ago (Fig. 1). Now, aquaculture supplies almost half of aquatic food consumed worldwide (FAO 2012). As demands for aquatic food are quickly increasing in global markets, aquaculture is expected to further expand in many countries, including both developing and developed countries (FAO 2012).

Figure 1.

Global and China aquaculture production in both quantity (ton) and value (US$) in each year. Data from FAO at

Among many factors responsible for fast expansion of aquaculture, the introduction and use of non-native species plays one of the most crucial roles (e.g. Shelton & Rothbard 2006; De Silva et al. 2009). However, accelerating introduction and/or use of non-native species have formed a paradox. There is little doubt that, like introduced crops and live-stock for agriculture, the introduction of aquatic species is a valid means to improve aquaculture production (Bartley et al. 2005; Gozlan 2008). For example, non-native finfish species contribute to approximately 17% of the world's production (FAO 2012). Some countries rely on farming of non-native aquatic species, for example, 60% of the freshwater harvest in the Philippines and 50% of the production in Brazil is derived from non-native species (Shelton & Rothbard 2006). However, unregulated introduction and irresponsible use of non-native species lead to severe risks and threats to local environments, economies and human activities (e.g. De Silva 2012). Owing to a huge contribution to economic growth, food supply and employment opportunities, risks have been highly overlooked and underestimated, although they have been pointed out three decades ago (Ryman 1981) and stressed repeatedly in subsequent scientific literature (e.g. Naylor et al. 2001; Bartley et al. 2005; De Silva et al. 2006, 2009; Laikre et al. 2010; De Silva 2012). Risks may appear more severe in many developing countries (e.g. De Silva et al. 2006, 2009), where economic growth and employment opportunities are considered as the most important national priorities.

Here, we discuss known and potential risks associated with the introduction and use of non-native species in China to urge the necessity of incorporating proper management into sustainable aquaculture. China serves as a good representative case study. Aquaculture in China expands fast in both production and farming area – the total production in 2011 is more than 50 million tons in quantity and US$ 64 million in value, nine and 15 times more than those 25 years ago (Fig. 1), and the farming area doubled during the past 25 years, reaching 7.8 million hm2 in 2011, of which the marine aquaculture area is six times more than 25 years ago (China Fisheries Yearbook 2012). Now, China dominates the reported aquaculture production, accounting for more than 60% of the global production (Fig. 1). In addition, the introduction and/or use of non-native species are accelerating in China, and more than 25% of the production is derived from farming of non-native species (Shelton & Rothbard 2006). However, China is vulnerable to establishment of non-native species (Yan et al. 2001). China spans five climatic zones (50° latitude), has more than 32 000 km of coastline and 17.5 million hm2 of inland water bodies, covers approximately 5200 km from east to west, and supports extremely divergent habitats. Non-native species may find suitable habitats to establish and subsequently spread to a wide geographical range (i.e. become invasive), although initial entry points may not provide preferred environmental conditions.

The aim of this review is to clarify the known and potential risks and to recommend solutions for proper management of sustainable aquaculture, rather than to ban the introduction and/or use of highly valued non-native species. Negative effects may appear suddenly or gradually as the time since establishment of non-native species is extended (Jeschke & Strayer 2005). However, lessons from known disasters are slowly learned (see known disasters in each section). Moreover, some risks and negative effects have been realized, but many remain unknown or overlooked. It is therefore necessary to perform comprehensive risk assessment on species that are proposed for introduction. In addition, research progress on management of harmful species has accumulated in the past two decades (e.g. Lodge et al. 2006; Messing & Wright 2006).

Based on such progress, we propose recommendations for the sound management of introduced non-native species for sustainable aquaculture. Sound management needs to be performed based on the characteristics of each aquaculture activity, such as scale, potential adverse effects and risks associated with each activity. Here, we discuss risks based on aquaculture activities popularly employed in the past several decades. We focus on high-risk activities and related events in this review. For each activity, we provide basic background, status of this activity in China, risks associated with this activity, and recommendations for management.

Transfers of non-native species


Aquaculture has become one key driver for the deliberate introduction of non-native species (Naylor et al. 2001; Peeler et al. 2011). So far, a total of 5612 records of species introduction have been collected by FAO (Database on Introductions of Aquatic Species, Given the fact of unavailability of data in some countries, especially developing countries in Asia where aquaculture expands fast, the number of introduction events is likely larger. The underestimated number can also be seen from the statistics performed by FAO: 76% of introduced species are made by unknown groups (Fig. 2).

Figure 2.

Organizations responsible for the total of 5612 records for the introduction of aquatic species for aquaculture. Data from Database on Introductions of Aquatic Species (DIAS) at FAO website (

Much attention has been paid to the international introduction of non-native species. The domestic transfer of species to locations where they do not naturally occur has been highly overlooked. Despite efforts made to minimize adverse effects, a well-recognized view of degree of risks and approaches to risk assessment have not been achieved in many countries, even those categorized as vulnerable ones to establishment of non-native species (Doupé & Lymbery 2000). Indeed, the domestic transfer is widely employed in geographically large countries such as China, where valued aquaculture species are usually restricted to limited geographical regions. The scale of domestic transfer, including the number of individuals, geographical sale involved and frequency of transfer, is much larger than that of international transfer, especially for commercial aquaculture purposes (e.g. Liu 2005; Shelton & Rothbard 2006). Despite the fact that the transfer of non-native species has gained attention from scientific communities (e.g. Naylor et al. 2001; De Silva et al. 2006, 2009; Laikre et al. 2010; De Silva 2012), many local and/or national governments have not regulated or not strictly regulated aquaculture-related introductions, especially for domestic transfers.

Species introductions in China

The introduction and use of non-native species for aquaculture in China started as early as 1920s (Fig. 3). A total of 179 species (virus and bacteria excluded) were internationally introduced into China for aquaculture or due to aquaculture-related activities (Table 1; Fig. 4a). These species include desired aquaculture species, accidental species transferred along with desired species (i.e. fellow travellers), and those introduced via other vectors but used as aquaculture species after introductions (Table 1). Due to difficulties to track origins and poor historical records of micro-organisms such as virus, bacteria and other pathogens, we excluded this group in this review. Among these 179 species, the top four taxonomic groups are fish (111 species), molluscs (27 species), algae (16 species), and crustaceans (14), accounting for 93.9% of all introductions (Fig. 4a). Among these four groups, fish and molluscs are the most diverse, covering ten orders and eight infraorders/families/superfamilies respectively (Fig. 4a). For introduced fish, the major group is Perciformes (39 species), accounting for 35.1%, while the most abundant groups of introduced molluscs are Haliotidae (7 species) and Pectinoida (7 species), accounting for 51.9% of the total (Fig. 4a).

Table 1. A list of non-native species introduced internationally into China. The native range, year of introduction, current distribution range, major negative effects in local environment and major reference for each species are shown.a The bolded species indicate contribution to aquaculture production in China
SpeciesNative rangeYear of introductionDistribution in ChinaNegative effects in local environment?Production (ton) in China (2011)Major reference
  1. a

    Information, such as year of introduction and current distribution of non-native species, may vary in different references, mainly due to unclear records, multiple introductions, and frequent transfers. For data accuracy, major/key journal articles and books are used to collect such information for this table. This also applies to Tables 2 and 3.

  2. b

    Procambarus clarkii: introduced via ballast water, but significant aquaculture in China.

  3. c

    Costaria costata: fellow traveller with introductions of Undaria pinnatifida from Japan.

  4. d

    Desmarestia ligulata: fellow traveller with introductions of Undaria pinnatifida from Japan.

  5. e

    Trichogloea lubrica: fellow traveller with introductions of Undaria pinnatifida from Japan.

  6. f

    Mytilus galloprovincialis: introduction vector unknown, but significant aquaculture in China.

  7. g

    Achatina fulica: introduction vector unknown, but significant aquaculture in China.

  8. h

    Pomacea canaliculata: introduced likely via hull fouling, but significant aquaculture in China.

  9. i

    Pygocentrus nattereri: introduced illegally, mainly kept as pet but aquacultured for food in some regions of China.

  10. j

    Osteoglossiformes: mainly introduced as pets but aquacultured for food as well in some regions of China.

Ascidia – 1 species
 Halocynthia roretzi (Sea pineapple)Japan & Korea2005Liaoning & Shandong Provs.Unknown Wang and Wang (2006)
Echinodermata – 2 species
 Apostichopus japonicus var. red (Red Japanese sea cucumber)Japan2004Shandong Prov.UnknownLi (2009)
 Strongylocentrotus intermedius (Japanese sea urchin)Japan1989Liaoning & Shandong Provs.Yes: destroy seagrass beds and aquaculture facilities, compete with native species for space and foodChang et al. (2000)
Amphibia – 4 species
 Rana catesbeiana (Bull frog)North America1959NationwideYes: predation on native species, especially amphibiansLi and Xie (2004)
 Rana grylio (Pig frog)North America1987Jiangsu, Zhejiang, Fujian, Hubei, Hunan & Anhui Provs.UnknownLi and Xie (2004)
 Rana heckscheri (American frog)North America1987Guangdong & Hunan Provs.UnknownLi and Xie (2004)
 Rana tigrina (Tiger frog)Thailand1995South ChinaUnknownFang et al. (2002)
Testudines – 4 species
 Annamemys annamensis (Vietnamese leaf turtle)Vietnam1997South ChinaUnknownLi et al. (2002)
 Chelydra serpentine (Alligator snapping turtle)North America1997East & South ChinaUnknownLin and Zhou (2001)
 Morenia petersi (Indian eyed turtle)India & BangladeshUnknownSouth ChinaUnknownLi et al. (2007a)
 Trachemys scripta (Red-eared slider)America1987South ChinaYes: exclude native species, predation on native speciesLi et al. (2005)
Crustacea – 14 species
Branchiopoda – 5 species
Artemia franciscana (San Francisco brine shrimp)America1989Coastal regions of ChinaUnknownTang and Lin (1993)
Artemia monica (Salt Lake brine shrimp)USAUnknownUnknownUnknownSun et al. (2000)
Artemia persimilis (Argentinian brine shrimp)South AmericaUnknownUnknownUnknownSun et al. (2000)
Artemia tanisiana (European brine shrimp)EuropeUnknownUnknownUnknownSun et al. (2000)
Artemia urmiana (Iranian brine shrimp)IranUnknownUnknownUnknownSun et al. (2000)
 Decapoda – 9 species
Cherax destructor (Australian crayfish yabby)Australia1998Jiangsu & ZhejiangUnknownLi et al. (2007a)
Cherax quadricarinatus (Australian red claw crayfish)Australia1992East & Southeast ChinaUnknownLi et al. (2007a)
Cherax tenuimanus (Australian crayfish)Australia1986HubeiUnknownLi et al. (2007a)
Macrobrachium rosenbergii (Malaysian prawn)Indo-Pacific & Southeast Asia1976NationwideUnknown122,933Li et al. (2007a)
Penaeus japonicus (Kuruma prawn)Indian & Pacific OceansUnknownSoutheast coastal regionsUnknown50,991Li et al. (2007a)
 Penaeus monodon (Black tiger prawn)Indian & Pacific Oceans1986Southern ChinaUnknown60,691Li et al. (2007a)
 Penaeus stylirostris (Blue shrimp)Latin America1988NationwideUnknownLi et al. (2007a)
 Penaeus vannamei (White-leg shrimp)South America1988NationwideUnknown665,588 (marine) 659,961 (freshwater)Li et al. (2007a)
 Procambarus clarkiib (Red swamp crayfish)USA, Central & South America1929NationwideYes: destroy dams, agriculture crop, and sessile communities.486,319Li et al. (2007a)
Algae – 16 species
 Blue-green algae – 2 species
Spirulina maxima (N/A)Mexico1970sHainan, Guangdong & Yunnan Provs.UnknownZhang and Yang (1997)
Spirulina platensis (N/A)Africa1985Hainan, Guangdong & Yunnan Provs.UnknownZhang and Yang (1997)
 Brown algae – 6 species
Costaria costatac (N/A)JapanUnknownLiaoning Prov.UnknownShao and Li (2000)
Desmarestia ligulatad (N/A)Japan1997Liaoning Prov.Yes: release sulphuric acid after deathShao and Li (2000)
Laminaria japonica (Kelp)Pacific Ocean1927Liaoning, Shandong, Zhejiang & Fujian Provs.UnknownLiang and Wang (2001)
Laminaria longissima (Narrow-leaved tangle)Pacific Ocean1990Liaoning & Shandong Provs.UnknownZhang et al.(1998)
Macrocystis pyrifera (Giant kelp)Mexico1978Jiangsu, Zhejiang & Shandong Provs.UnknownLiang and Wang (2001)
Undaria pinnatifida (Wakame)Japan & Korea1940sLiaoning & Shandong Provs.Yes: quick growth, reduce native seaweed diversity134,175Liang and Wang (2001)
 Green algae – 3 species
Dunaliella salina (Teodoresce)Mediterranean1986High-salt WatersUnknownSun (2000)
Nannochloropsis oculata (N/A)Japan1991Jiangsu, Zhejiang & Shandong Provs.UnknownLiu et al. (1999)
Tetraselmis sp. (Green flagellate)Canada1996Jiangsu, Zhejiang & Shandong Provs.UnknownZou and Zhang (2003)
 Red algae – 5 species
Eucheuma amakusaensis (N/A)Japan1984Guangdong Prov.UnknownLiang and Wang (2001)
Eucheuma striatum (N/A)Asia1985South ChinaUnknownZeng (2001)
Palmaria palmata (N/A)Atlantic & Pacific Oceans2005Lab onlyUnknownPang (2005)
Porphyra yezoensis (N/A)Japan & Korea1986Coastal provincesUnknownMao (1988)
Trichogloea lubricae (N/A)Japan1997Liaoning Prov.UnknownShao and Li (2000)
Mollusca – 27 species
 Pectinoida – 7 species
Argopecten irradians (Bay scallop)Atlantic Ocean1982Coast of North ChinaUnknown800,000Zhang et al. (1997)
Argopecten purpuratus (Peruvian scallop)Peru2007Shandong Prov.UnknownGuo (2009)
Chlamys asperrima (Doughboy scallop)Australia2001Shandong Prov.UnknownLiu et al. (2003)
Notovola meridionalis (Tasmanian scallop)Australia2000Shandong Prov.UnknownLiu et al. (2003)
Patinopecten yessoensis (Yesso scallop)Japan, Korea & Russia1980North ChinaUnknown250,000Li et al. (2007a)
Pecten maximus (Great scallop)English Channel & Iceland1999North ChinaUnknownLi et al. (2007a)
Placopecten magellanicus (Giant scallop)Canada2005Shandong Prov.UnknownQin et al. (2009)
 Ostreoida – 4 species
Crassostrea gigas (Pacific oyster)Japan, Australia1979NationwideYes: fouling species with high abundance on vessels and aquaculture facilitiesGuo (2009) and Sun et al. (2010)
Crassostrea nippona (Iwagaki oyster)JapanUnknownShandong Prov.UnknownTeng (2009)
Crassostrea sikamea (Kumomoto oyster)Japan2007Shandong Prov.UnknownTeng (2009)
Crassostrea virginica (American oyster)East coast of North America1986Shandong Prov.UnknownLi et al. (2007a)
 Unionoida – 2 species
Hyriopsis Schlegeli (Biwa pearly mussel)Japan1997Jiangxi & Zhejiang Provs.UnknownLi et al. (2007a)
Potamilus alatus (Pink heelsplitter)America2002Jiangsu & Guangdong Provs.UnknownLi et al. (2007a)
 Veneroida – 2 species
Mercenaria mercenaria (Hard-shell clam)USA1997Shandong, Liaoning, Jiangsu & Zhejiang Provs.UnknownLi et al. (2007a)
Spisula solidissima Atlantic SurfclamEast Coast, USA2002Shandong & Liaoning Provs.UnknownGuo (2009)
 Mytiloida – 1 species
Mytilus galloprovincialisf (Mediterranean mussel)Mediterranean, Black, Adriatic SeasUnknownNationwideYes: fouling species with high abundance on vessels and aquaculture facilitiesLi et al. (2007a)
 Myoida – 1 species
Panopea abrupta (Geoduck)USA & Canada1985Shandong & Liaoning Provs.UnknownLi et al. (2007a)
 Achatinoidea – 1 species
Achatina fulicag (African giant snail)Africa1930South ChinaYes: pest in agriculture and horticulture, vector for disease-causing pathogensLi et al. (2007a)
 Neogastropoda – 1 species
Babylonia spirata (Spotted baigai)Indian Ocean & west PacificUnknownSouth ChinaUnknownHarasewych and Moretzsohn (2010)
 Haliotidae – 7 species
Haliotis discus discus (Pacific abalone)Japan1996Shandong & Liaoning Provs.Yes: genetic introgression into local gene poolsZhang et al. (2004)
Haliotis fulgens (Green abalone)USA & Mexico1985South ChinaUnknownLi et al. (2007a)
Haliotis gigantea (Japanese abalone)Japan1998Shandong & Liaoning Provs.UnknownSun et al. (2001)
Haliotis iris (Blackfoot paua)West Pacific1999UnclearUnknownLiang and Wang (2001)
Haliotis laevigata (Smooth Australian abalone)Australia2000Guangdong Prov.UnknownYang and Cai (2002); Guo (2009)
Haliotis refescens (Red abalone)USA & Mexico1985South ChinaUnknownLi et al. (2007a)
Haliotis rubra (Blacklip abalone)AustraliaUnknownSouth ChinaUnknownHou (1998)
 Ampullariidae – 1 species
Pomacea canaliculatah (Apple snail)South America1977Southern ChinaYes: pest in agriculture, vector for disease-causing pathogensLi et al. (2007a)
Fish – 111 species
 Acipenseriformes – 9 species
Acipenser baeri (Siberian sturgeon)Europe1996NationwideUnknownLi et al. (2007a)
Acipenser gueldenstaedtii (Russian Sturgeon)Europe1993Mainly in Xinjiang & Heilongjiang Provs.UnknownLi et al. (2007a)
Acipenser nudiventris (Bastard sturgeon)Black, Caspian & Aral Seas1993XinjiangUnknownLi et al. (2007a)
Acipenser ruthenus (Sterlet)Europe1997NationwideUnknownLi et al. (2007a)
Acipenser stellatus (Star sturgeon)EuropeUnknownNorth ChinaUnknownRen and Ma (2001)
Acipenser transmontanus (White sturgeon)North AmericaUnknownNorth ChinaUnknownRen and Ma (2001)
Huso huso (Beluga Sturgeon)EuropeUnknownMany provinces in coastal regions and middle ChinaUnknownRen and Ma (2001)
Huso huso♀ × Acipenser ruthenus♂ (Bester)Created in Union of Soviet Socialist Republics1998North & Northeast ChinaUnknownLi et al. (2007a)
Polyodon spathula (American paddlefish)USA1988NationwideUnknownXiong et al. (2008a)
 Anguilliformes – 4 species
Anguilla anguilla (European eel)Europe1991Southeast ChinaUnknownLi et al. (2007a)
Anguilla australis (Shortfin eel)Australia2005Jiangsu, Zhejiang, Fujian, Guangdong Provs.UnknownLi et al. (2007a)
Anguilla mossambica (African longfin eel)West Indian Ocean2007South ChinaUnknownFan et al. (2008)
Anguilla rostrata (American eel)East coast of North America1978Jiangsu, Zhejiang, Fujian, Guangdong Provs.UnknownLi et al. (2007a)
 Characiformes – 4 species
Colossoma brachypomum (Freshwater spadefish)South America1982NationwideUnknown94,942Li et al. (2007a)
Piaractus mesopotamicus (Pacu)Brazil1996Mainly in Jiangsu & Zhejiang Provs.UnknownLi et al. (2007a)
Prochilodus scrofa (Shad)South America1996NationwideUnknownLi et al. (2007a)
Pygocentrus nattererii (Red bellied piramha)South America1990NationwideYes: predation on almost all native species, attack human beingsLi et al. (2007a)
 Clupeiformes – 16 species
Alosa sapidissima (American shad)East coast of North America2001Guangdong, Shanghai, Zhejiang, Shandong, Jiangsu, Fujian Provs.UnknownLi et al. (2007a)
Abramis brama orientalis (European bream)Caspian & Aral Seas1949XinjiangUnknownLi et al. (2007a)
Barbodes schwanenfeldii (Tinfoil barb)Southeast Asia1997South ChinaUnknownSong et al. (2012)
Carassius auratus cuvieri (Crucian carp)Japan1959Many freshwater bodiesUnknownLi et al. (2007a)
Catla catla (Catla)South Asia1973Mainly in Guangdong, Guangxi & Hainan Provs.UnknownLi et al. (2007a)
Chalcalburnus chalcoides (Danube bleak)Black, Caspian & Aral Seas2001Heilongjiang, Hebei Shandong & ShanghaiUnknownLi et al. (2007a)
Cirrhinus mrigala (Mrigal)Coast of Indian Ocean1982Pearl River basin & Hainan Prov.UnknownLi et al. (2007a)
Cyprinus carpio (Russian commom carp)Russian1958Northwest ChinaYes: genetic introgression into local gene poolsLi et al. (2007a)
Cyprinus carpio var. mirror (Scattered mirror carp)Ukraine1958NationwideYes: genetic introgression into local gene poolsLi et al. (2007a)
Cyprinus carpio var. specularis (German mirror carp)German1982NationwideYes: genetic introgression into local gene poolsLi et al. (2007a)
Ictiobus cyprinellus (Common buffalo)USA & Canada1993Yangtze River & Pearl River basinsUnknownLi et al. (2007a)
Labeo calbasu (Black Rohu)Southeast Asia1990Guangdong Prov.UnknownLou (2000)
Labeo rohita (Rohu)Southeast Asia1978South ChinaUnknownLi et al. (2007a)
Leptobarbus hoevenii (Mad barb)Southeast Asia1988Taiwan & Guangdong Provs.UnknownLi et al. (2007a)
Puntius gonionotus (Java barb)Southeast Asia1986Guangdong Prov.UnknownLi et al. (2007a)
Tinca tinca (Tench)Europe1998Guangdong, Hubei, Jiangsu & Sichuan Provs.UnknownLi et al. (2007a)
 Osteoglossiformesj – 8 species
Arapaima gigas (Paiche)South America1990Guangdong & Shandong Provs.UnknownLou (2000)
Gnathonemus petersi (Elephantnose fish)Africa1990Guangdong Prov.UnknownLou (2000)
Notopterus blanci (Royal Clown Knife)Southeast Asia1990Guangdong Prov.UnknownLou (2000)
Notopterus chitala (Clown Knife)Southeast Asia1990Guangdong Prov.UnknownLou (2000)
Osteoglossum bicirrhosum (Silver arowana)South America1990Guangdong Prov.UnknownLou (2000)
Osteoglossum ferreirai (Black arowana)South America1990Guangdong Prov.UnknownLou (2000)
Scleropages formosus (Asian arowana)Southeast Asia1990Guangdong Prov.UnknownLou (2000)
Scleropages leichardti (Australian arowana)Australia1990Guangdong Prov.UnknownLou (2000)
 Perciformes – 39 species
Bidyanus bidyanus (Silver perch)Australia1999Mainly in Fujian & Guangdong ProvsUnknownLi et al. (2007a)
Centropristis striata (Atlantic seabass)East coast of North America2002Shandong Prov.UnknownLi et al. (2007a)
Channa micropeltes (Giant snakehead)Southeast Asia1986Shandong Prov.UnknownLi et al. (2007a)
Channa striatus (Snakehead)Southeast Asia1992South ChinaYes: predation on fish, amphibians and crustaceansLi (1992)
Cichlasoma sp. (N/A)Africa1989Guangdong Prov.UnknownLou (2000)
Cynoscion nebulosus (Spotted seatrout)North America1997Shandong, Zhejiang, Fujian, Beijing & LiaoningUnknownLi et al. (2007a)
Eleotris fusca (Dusky sleeper)Southeast Asia1999Guangdong Prov.UnknownLi et al. (2007a)
Hephaestus fuliginosus (Black bream)Australia1998Guangdong, Hebei, Zhejiang & Jiangsu Provs.UnknownLi et al. (2007a)
Lates calcarifer (White sea bass)Southeast Asia1984South China Sea & East China SeaUnknownLi et al. (2007a)
Lepomis auritus (Redbreast sunfish)North America1987Hubei & Hainan Provs.UnknownChen and Ye (1992)
Lepomis cyanellus (Green sunfish)North America1999Guangdong, Hubei & Zhejiang Provs.UnknownLi et al. (2007a)
Lepomis macrochirus (Bluegill sunfish)North America1987Hubei, Hunan, Zhejiang & Guangdong Provs.UnknownLi et al. (2007a)
Lepomis megalotis (Longear sunfish)North America1987Hubei & Hainan Provs.UnknownChen and Ye (1992)
Lepomis nigromaculatus (N/A)North America1989Hubei Prov.UnknownChen et al. (2010)
Lucioperca lucioperca (Pike-perch)Europe1960Beijing, Tianjin & HubeiUnknownLi et al. (2007a)
Maccullochella peelii peelii (Murray cod)Australia2001Zhejiang Prov.UnknownLi et al. (2007a)
Macquaria ambigua (Murrray perch)Australia1991South ChinaUnknownLi et al. (2007a)
Micropterus salmoides (Largemouth bass)USA & Canada1983Central & South ChinaYes: compete with native fish for food and spaceLi et al. (2007a)

  Morone chrysops♀ × M. saxatilis

(Hybrid striped bass)

Created in USA1993Yellow Sea & East China SeaUnknownLi et al. (2007a)
Morone saxatilis (Striped bass)USA & Canada1997Yellow Sea & East China SeaUnknownLi et al. (2007a)
Oreochromis andersonii (Threespot tilapia)Africa1987NationwideUnknownChen and Ye (1994)
Oreochromis aureus (Blue tilapia)Africa & Middle East1981NationwideUnknownLi et al. (2007a)
Oreochromis aureus♂ × O.  niloticus♀ (N/A)N/AUnknownSouth ChinaUnknownChen and Ye (1994)
Oreochromis mossambicus (Mozambique tilapia)Africa1956NationwideUnknownLi et al. (2007a)
Oreochromis mossambicus♂ ×  O. niloticus♀ (N/A)N/AUnknownNationwideUnknownChen and Ye (1994)
Oreochromis niloticus (Nilotica tilapia)Africa1978NationwideUnknownLi et al. (2007a)
Oreochromis hornorum (Hornorum tilapia)Africa2001NationwideUnknownLi et al. (2007a)
Oxyeleotris lineolatus (Sleepy cod)Australia1996Pearl River basinUnknownLi et al. (2007a)
Oxyeleotris marmorata (Marble goby)Southeast Asia1988Pearl River basinUnknownLi et al. (2007a)
Parachromis managuensis (Jaguar guapote)Central America1988Guangdong & Guangxi Provs.UnknownLi et al. (2007a)
Perca flavescens (Yellow perch)USA & Canada2003NationwideUnknownLi et al. (2007a)
Sarotherodon galilaeus (Tilapia galilaea)Africa1978Hubei Prov.UnknownLi et al. (2007a)
Sarotherodon melanotheron (Blackchin tilapia)Africa2002Guangdong & Hebei Provs.UnknownLi et al. (2007a)
Sciaenops ocellatus (Red drum)East coast of North America1991Shandong, Zhejiang, Fujian, Guangdong & Hainan Provs.Unknown64,838Li et al. (2007a)
Scortum barcoo (Jade perch)Australia2002NationwideUnknownLi et al. (2007a)
Sparus aurata (Gilthead seabream)France2001TianjinUnknownWang et al. (2010d)
Stizostedion vitreum (Walleye)North America1993Heilongjiang Prov.UnknownLi et al. (2007a)
Tilapia sp. (Red tilapia)Africa1973Guangdong, Fujian & Guangxi Provs.UnknownLi et al. (2007a)
Tilapia zillii (Zill's tilapia)Africa1963Guangdong Prov.UnknownLi et al. (2007a)
 Pleuronectiformes – 4 species
Paralichthys dentatus (Atlantic flounder)Atlantic Ocean2002Shandong, Jiangsu & Fujian Provs.UnknownLi et al. (2007a)
Paralichthys lethostigma (Southern flounder)USA2002More than 10 provs.UnknownLi et al. (2007a)
Scophthalmus maximus (Black sea turbot)Europe1992Bohai SeaUnknownLi et al. (2007a)
Solea senegalensis (Senegalese sole)Europe2001North ChinaUnknownLiu et al. (2008)
 Salmoniformes – 16 species
Coregonus autumnalis migratorius (Lake Baikal omul)Europe1998XinjiangUnknownGuo (2005)
Coregonus lavaretus maraenoides (Eurasian whitefish)North America & Russia1985Heilongjiang Prov.UnknownLi et al. (2007a)
Coregonus muksum (Muksun)Europe2003XinjiangUnknownGuo (2005)
Coregonus nasus (Broad whitefish)Europe1987HeilongjiangUnknownLi et al. (2007a)
Coregonus peled (Whitefish)North America & Russia1985North ChinaUnknownLi et al. (2007a)
Coregonus sardinella (Sardine cisco)Europe2003XinjiangUnknownGuo (2005)
Coregonus tugun (Tugun)Europe2003XinjiangUnknownGuo (2005)
Oncorhynchus gorbuscha (Pink salmon)North Pacific Ocean1987Heilongjiang Prov.UnknownLi et al. (2007a)
Oncorhynchus keta (Calico salmon)North Pacific Ocean1988HeilongjiangUnknownLi et al. (2007a)
Oncorhynchus kisutch (Coho salmon)North Pacific Ocean1982LiaoningUnknownLi et al. (2007a)
Oncorhynchus mykiss (Rainbow trout)West coast of North America1959NationwideUnknownLi et al. (2007a)
Salmo aguabonita (golden trout)Japan1996NationwideUnknownLi et al. (2007a)
Salmo salar (Atlantic salmon)Northern Atlantic Ocean2000Heilongjiang, Beijing, Hebei & Shandong Provs.UnknownLi et al. (2007a)
Salmo trutta fario (Brown trout)Europe1976TibetUnknownLou (2000)
Salvelinus fontinalis (Brook trout)Canada & USA2005Shandong Prov.UnknownLi et al. (2007a)
Salvelinus leucomaenis pluvius (Rain-speckled trout)Japan1996Mainly in Heilongjiang & BeijingUnknownLi et al. (2007a)
 Siluriformes – 10 species
Clarias batrachus (Walking catfish)Southeast Asia1978Guangdong Prov.UnknownLi et al. (2007a)
Clarias lazera (North African catfish)Africa1981NationwideUnknownLi et al. (2007a)
Clarias macrocephalus (Broadhead catfish)Southeast Asia1982South ChinaUnknownLi et al. (2007a)
Ictalurus furcatus (Blue catfish)North America1989Hubei Prov.UnknownLou (2000)
Ictalurus nebulosus (Brown bullhead)North America1984NationwideUnknownLi et al. (2007a)
Ictalurus punctatus (Channel catfish)North America1983NationwideUnknownLi et al. (2007a)
Pangasianodon gigas (Mekong giant catfish)Southeast Asia1986Yunnan Prov.UnknownLi et al. (2007a)
Pangasius sp. (Irridescent shark)Southeast Asia2000South ChinaUnknownLi et al. (2007a)
Pangasius sutchi (Sutchi catfish)Southeast Asia1978NationwideUnknownLi et al. (2007a)
Silurus glanis (Wels catfish)Europe1991Hubei Prov.UnknownLi et al. (2007a)
 Tetraodontiformes – 1 species
Fugu(Takafugu) rubripes (Tiger pufferfish)Japan & Korea1996Mainly in Shandong & Liaoning Provs.UnknownHao et al. (2005)
Figure 3.

Number of non-native species introduced into China due to aquaculture or related activities (bar chart and left x-axis), and total aquaculture production in China in the past 90 years (dotted line and right x-axis).

Figure 4.

Taxonomic composition of non-native species internationally introduced into China (a) and domestically transferred within China (b) due to aquaculture or related activities. The number of species in each taxon is shown in brackets after taxon name.

The number of species introduced before 1970 was small, totally 13 in this half century (1920–1969). Frequent introductions began from 1970s as the total aquaculture production started to sharply increase. More than 150 species were introduced in the past forty years, with an average 3.8 species per year (Fig. 3). The largest number was detected in 1990s, with a total of 56 species introduced. These introduced species contribute to the fast expansion of aquaculture in China. A large proportion of these introduced species (52.5%) has been successfully cultured (Table 1), and these non-native species have contributed to aquaculture production in China (>25% of total production; Shelton & Rothbard 2006). Two well-known examples are the introductions of the Pacific white shrimp Penaeus vannamei and red swamp crayfish Procambarus clarkii. The total production of the Pacific white shrimp doubled in both marine and freshwater aquaculture in the past 10 years, from 308 947 ton in 2003 to 665 588 ton in 2011 (marine) and from 296 312 ton in 2003 to 659 961 ton (freshwater), accounting for 74.3% (marine) and 43.6% (freshwater) of the total production of category ‘shrimp, prawn, crayfish and lobster’ (Fig. 5). Although negative effects of the red swamp crayfish were well recognized and emphasized in both scientific literature and public media in the beginning of 2000s (e.g. Wang 2003), aquaculture still expands and production keeps increasing, reaching 563 281 ton in 2010, more than ten times than that in 2003 (Fig. 5). Now, the production of this crayfish accounts for more than 30% of the total production of the category ‘shrimp, prawn, crayfish and lobster’ (Fig. 5).

Figure 5.

Aquaculture production in the category of ‘shrimp, prawn, crayfish and lobster’ from 2003 to 2011 (line graph), and production proportion of each major species in each year (pie chart) in China. Data from China Fisheries Yearbook (2004–2012).

For domestic transfers, almost all provinces in China, including inland and coastal ones, have introduced species for aquaculture. A total of 73 species (virus and bacteria excluded) have clear records of transfer beyond their native ranges (Table 2; Fig. 4b). Among these 73 species, the most abundant group is fish (61 species), accounting for 83.6% of all introduced species (Fig. 4b). The introduced fish cover 12 orders, of which Cypriniformes is the largest (25 species, Fig. 4b). Although 12 species are detected to have negative effects/history of biological invasions, they have been transferred and employed for aquaculture (Table 2).

Table 2. Aquaculture species transferred from native range to where they naturally do not occur within China due to aquaculture activities. Species only with clear and available records are listed. The native range, introduced range, history of biological invasions, and major reference for each species are shown
SpeciesNative rangeIntroduced rangeHistory of biological invasionsMajor reference
Algae – 2 species
Red algae – 2 species
Porphyra haitanensis (−)South ChinaNorth ChinaNoLi et al. (1992)
Gracilaria lemaneiformis (−)Bohai and Yellow SeasSouth ChinaNoPeng et al. (2007)
Amphibia – 2 species
Andrias davidianus (Chinese giant salamander)Mainly in Yangtze and Pearl River drainagesMany provinces such as ShandongNoLiu (2004)
Rana chensirtensis (Chinese wood frog)Northeast China, Qinling-Daba mountainsSouth China such as Zhejiang Prov.NoQian and Chen (2003)
Crustacea – 3 species
Decapoda – 3 species
Eriocheir sinensis (Chinese mitten crab)North to Liaoning, South to Fujian, West to Hubei Prov.Almost all provincesYesRen and Shao (2004)
Macrobrachium nipponense (Oriental river prawn)Wide distribution from Shandong to Fujian Provs.Northeast provinces such as HeilongjiangNoChen (1997)
Scylla serrata (Giant mud crab)South ChinaNorth ChinaYesLiu et al. (1995)
Fish – 61 species
Acipenseriformes – 1 species
Acipenser schrenckii (Amur sturgeon)Heilongjiang, Songhuajiang, Wusulijiang RiversMore than 8 provinces such as Shandong, GuangdongNoWang et al. (2009b)
Anguilliformes – 1 species
Anguilla japonica (Japanese eel)Coastal provinces, rivers in Sichuan Prov.Lakes in Yungui PlateauNoXiong et al. (2008ab) and Wang et al. (2009b)
Beloniformes – 1 species
Hyporhamphus intermedius (Asian pencil halfbeak)Nationwide except Yungui PlateauLakes in Yungui PlateauNoXiong et al. (2008ab) and Wang et al. (2009b)
Cypriniformes – 25 species
Abbottina rivularis (Chinese false gudgeon)Nationwide except some water bodies such as Tarim RiverTarim River, Lakes in Yunnan Prov.NoWang (1995) and He et al. (2010)
Acheilognathus chankaensis (Khanka spiny bitterling)UnclearLake Erhai in Yunnan Prov.NoHe et al. (2010)
Carassius auratus gibelio (Silver crucian carp)Heilongjiang-Liaohe drainageNationwideYesWang et al. (2009b)
Carassius carassius carassius (Irtysh River carp)Irtysh RiverTarim RiverNoWang (1995)
Chanodichthys erythropterus (Skygazer)Nationwide except Yungui PlateauLakes in Yungui PlateauNoWang et al. (2009b)
Ctenopharyngodon idellus (Grass carp)Mainly in Yangtze and Peal RiversLakes in west plateau provinces, e.g. Yunnan and Xinjiang Autonomous RegionYesWang et al. (2009b)
Culter erythropterus (Redfin culter)Major rivers in East ChinaLake FuxianNoXiong et al. (2008ab)
Cyprinus carpio (Common carp)NationwideIntroduced into enclosed lakes in many provinces such as YunnanYesWang et al. (2009b)
Erythroculter dabryi (Lake skygazer)Nationwide except Yungui PlateauLakes in Yungui PlateauNoXiong et al. (2008ab) and Wang et al. (2009b)
Gobio gobio cynocephalus (−)UnclearTarim RiverNoWang (1995)
Hemibarbus maculatus (Spotted steed)Yangtze River drainageTarim RiverNoWang (1995)
Hemiculter leucisculus (Sharpbelly)Nationwide except Yungui PlateauLakes in Yungui PlateauNoWang et al. (2009b) and He et al. (2010)
Hypophthalmichthys molitrix (Silver carp)Southeast ChinaYunnan Prov.YesWang et al. (2009b)
Hypophthalmichthys nobilis (Bighead carp)Northeast and north ChinaQinghai, Yunnan, Guizhou, Liaoning Provs.; Xizang, Inner Mongolia Autonomous RegionsYesWang et al. (2009b)
Leuciscus baicalensis (Siberian dace)Irtysh River and Ulungur RiverTarim RiverNoWang et al. (2010c)
Leuciscus idus (Golden ide)Irtysh RiverLake UlungurNoKarjan et al. (2006)
Megalobrama amblycephala (Wuchang fish)Yangtze River drainageNationwideNoWang (1995)
Magalobrame Tarminalis (Black Amur bream)Rivers in Northeast ChinaTarim RiverNoWang (1995)
Misgurnus anguillicaudatus (Oriental weatherfish)Nationwide except Tibetan PlateauTibetan Plateau and Xinjiang Autonomous RegionNoWang et al. (2010c)
Mylopharyngodon piceus (Black carp)Mainly in Yangtze and Peal RiversLakes in west plateau provinces, e.g. Yunnan and Xinjiang Autonomous RegionYesWang et al. (2009b)
Paramisgurnus dabryanus (Chinese loach)East and Northeast ChinaLake FuxianNoXiong et al. (2008ab)
Rhodeus nobilis (−)East ChinaLake FuxianNoXiong et al. (2008ab)
Rhodeus sinensis (Chinese bitterling)Nationwide except Yungui PlateauLakes in Yungui PlateauNoWang et al. (2009b) and He et al. (2010)
Rutilus rutilus lacustris (Siberian roach)Irtysh River and Lake Bosten in Xinjiang Autonomous RegionTarim River, Lake UlungurNoWang (1995) and Karjan et al. (2006)
Xenocypris microlepis (−)Nationwide except some water bodies such as Tarim RiverTarim RiverNoWang (1995)
Esociformes – 1 species
Esox lucius (Northern pike)Irtysh River in Xinjiang Autonomous RegionYellow River drainage, Lake UlungurNoKarjan et al. (2006) and Li et al. (2008)
Gadiformes – 1 species
Lota lota (Burbot)Heilongjiang RiverLake UlungurNoKarjan et al. (2006)
Osmeriformes – 9 species
Hemisalanx brachyrostralis (−)Middle and lower reaches of Yangtze RiverThree Gorges ReservoirNoBa and Chen (2012)
Hypomesus olidus (Pond smelt)Heilongjiang and Tumenjiang RiversYellow River drainage, Lake UlungurYesKarjan et al. (2006) and Li et al. (2008)
Hypomesus transpacificuc nipponesis (Asian pond smelt)Liaoning Prov.North China including Shandong, Heilongjiang, Jilin Provs.NoZhao et al. (2003)
Leucosoma chinensis (White muscle icefish)Water bodies along East China and South China SeasYangtze RiverNoBa and Chen (2012)
Neosalanx taihuensis (Noodlefish)Mainly in Lake TaiNorth to Inner Mongolia, South to Yunnan Prov, West to Sichuan Prov.YesWang et al. (2009b)
Plecoglossus altivelis (Ayu)Water bodies along the coasts of Bohai, Yellow and East China SeasMany coastal provinces such as ShandongNoLiu et al. (2003)
Protosalanx chinensis (Chinese icefish)Mainly in Lake TaiNorth to Inner Mongolia, South to Yunnan Prov, West to Sichuan Prov.YesWang et al. (2009b)
Protosalanx hyalocranius (Clearhead icefish)Mainly in water bodies from Shandong to Zhejiang Prov.Yellow River drainageNoLi et al. (2008)
Salanx prognathus (−)Lakes Poyang and TaiThree Gorges ReservoirNoBa and Chen (2012)
Perciformes – 11 species
Hephaestus fuliginosus (Sooty grunter)Lower reaches of the Yellow River and other main river drainagesMiddle and upper reaches of the Yellow RiverNoLi et al. (2008)
Hypseleotris swinhonis (−)Nationwide except Yungui PlateauLakes in Yungui PlateauNoWang et al. (2009b) and He et al. (2010)
Lucioperca Lucioperca (Pike-perch)Irtysh river in Xinjiang Autonomous RegionMore than 5 provs including Shandong, Hubei, JiangsuNoKarjan et al. (2006) and Wang et al. (2009ab)
Macropodus ocellatus (Roundtail paradise fish)Typically provinces in north of Yangtze RiverTarim River, Lake ErhaiNoWang (1995) and He et al. (2010)
Odontobutis potamophila (Dark sleeper)Yangtze, Qiantangjiang and Minjiang drainagesTarim river in Xinjiang Autonomous RegionNoWang et al. (2010c)
Perca fluviatilis (Eurasian perch)Irtysh river in Xinjiang Autonomous RegionLake Bosten in Xinjiang Autonomous RegionYesWang et al. (2009a)
Plectropomus leopardus (Coral trout)South China SeaNorth China such as Tianjin and Shandong Prov.NoZhang et al. (2011)
Pseudosciaena crocea (Large yellow croaker)Typically from South Yellow Sea to South China SeaNorth China such as Shandong Prov.NoKong and Xiong (2002)
Rachycentron canadus (Black kingfish)    
Rhinogobius cliffordpopei (−)Mainly in Yangtze River drainageLakes in Yungui PlateauNoWang et al. (2009b)
Siniperca chuatsi (Mandarin fish)Water bodies with altitude lower than 300 mTarim River, Yellow River drainageNoWang (1995)
Pleuronectiformes – 4 species
Platichthys stellatus (Starry flounder)North ChinaSouth China including Zhejiang, Fujian Provs & Guangxi Autonomous RegionNoZhuang et al. (2009)
Kareius bicoloratus (Stone flounder)Bohai Sea & Yellow SeaFujian Prov.NoZheng (2009)
Cynoglossus semilaevis (Tongue sole)Mainly in Bohai Sea & Yellow SeaSouth China, e.g. Zhejiang, Fujian, Guangdong, Hainan Provs.NoTang et al. (2007)
Paralichthys olivaceus (Olive flounder)Coast from Pear River to Yalu River estuariesGuangxi Autonomous RegionNoYang et al. (2007)
Salmoniformes – 1 species
Hucho taimen (Siberian salmon)Heilongjiang RiverLake UlungurNoKarjan et al. (2006)
Siluriformes – 5 species
Clarias fuscus (Chinese catfish)South ChinaLakes in Yungui PlateauNoWang et al. (2009b)
Pelteobagrus fulvidraco (Yellow catfish)Nationwide except west Plateau areaYunnan Prov.NoXiong et al. (2008ab) and Wang et al. (2009b)
Silurus Lanzhouensis (Yellow River catfish)Yellow River from Ningxia to Shandong Prov.ShanghaiNoBian et al. (2010)
Silurus meridionalis (Southern catfish)Provinces in south of the Yangtze RiverYellow River drainageNoLi et al. (2008)
Silurus soldatovi (Northem sheatfish)North China, mainly in Songhuajiang, Heilongjiang, Nenjiang RiversLakes in Yungui PlateauNoXiong et al. (2008ab) and Wang et al. (2009b)
Tetraodontiformes – 1 species
Fugu rubripes (Torafugu)Bohai, Yellow and East China SeasCoastal provinces such as ShandongNoLiu et al. (2003)
Mollusca – 5 species
Arcoida – 1 species
Arca inflata (Blood cockle)North Yellow SeaSouth ChinaNoChen (2007)
Haliotoidea – 2 species
Haliotis discus hannai (Pacific abalone)Bohai Sea and North Yellow SeaSouth China such as Fujian and Guangdong Provs.NoLin (2010)
Haliotis diversicolor aquatilis (−)Taiwan Prov.South ChinaNoSu (2006)
Pterioida – 2 species
Pinctada martensii (Pearl oyster)South ChinaNorth ChinaNoWei et al. (1997)
Pinctada maxima (Large pearl oyster)Hainan Island & Xisha ArchipelagoGuangdong Prov. and Guangxi Autonomous RegionNoShen and He (1990)
Table 3. Successful inter-specific hybridization with non-native species involved in China. Names of non-native species are bolded. ‘Adult hybrids successfully obtained’ is used as an indicator of ‘successful hybridization’
Taxonomic groupHybridization setupMajor reference
EchinodermsStrongylocentrotus intermedius (♀) × S. nudus (♂)Wang et al. (2003)
MolluscsArgopecten purpuratus (♀) × A. irradians (♂)Wang et al. (2009a)
Argopecten irradians (♀) × A. purpuratus (♂)Zhang et al. (2012a)
Haliotis discus hannai (♀) × H. gigantea (♂)Wang (2006)
Haliotis gigantea (♀) × H. discus (♂)Wang (2006)
Haliotis discus hannai (♀) × Haliotis discus discus (♂)Wan et al. (2001)
Haliotis discus discus (♀) × Haliotis discus hannai (♂)Wan et al. (2001)
Haliotis fulgens (♀) × Haliotis discus hannai (♂)Fan (2012)
Haliotis discus hannai (♀) × Haliotis fulgens (♂)Fan (2012)
Haliotis refescens (♀) × Haliotis discus hannai (♂)Wang and Fan (1999)
Haliotis discus hannai (♀) × Haliotis refescens (♂)Wang and Fan (1999)
Crassostrea gigas (♀) × C. ariakensis (♂)Zhang et al. (2012b)
Crassostrea ariakensis (♀) × C. gigas (♂)Zhang et al. (2012b)
Crassostrea sikamea (♀) × C. gigas (♂)Teng (2009)
Crassostrea gigas (♀) × C. sikamea (♂)Teng (2009)
AlgaeLaminaria longissima (♀) × L. japonica (♂)Li et al. (2007b)
Laminaria japonica (♀) × L. longissima (♂)Zhang et al. (2007)
FishAcipenser schrencki (♀) × A. ruthozus (♂)Wang et al. (2010a)
Acipenser schrencki (♀) × Huso huso (♂)Ren et al. (2012)
Huso dauricus (♀) × Acipenser baeri (♂)Liu et al. (2007b)
Huso huso (♀) × Acipenser baeri (♂)Gao et al. (2006)
Acipenser schrencki (♀) × A. gueldenstaedti (♂)Sun et al. (2009)
Acipenser schrencki (♀) × (Huso huso ♀ × Acipenser ruthenus ♂) (♂)Sun et al. (2009)
Acipenser gueldenstaedti (♀) × Huso dauricus (♂)Hu et al. (2008)
Acipenser baeri (♀) × Huso dauricus (♂)Hu et al. (2008)
Acipenser ruthozus (♀) × Huso dauricus (♂)Hu et al. (2008)
Acipenser gueldenstaedti (♀) × A. baeri (♂)Hu et al. (2008)
Acipenser baeri (♀) × A. schrencki (♂)Wang et al. (2010b)
Acipenser ruthozus (♀) × A. schrencki (♂)Wang et al. (2010b)
Acipenser schrencki (♀) × A. baeri (♂)Wang et al. (2010b)
Huso huso (♀) × Acipenser ruthozus (♂)Yang (2006)
Oxyeleotris marmorata (♀) × O. lineolatus (♂)Fan et al. (2009)
Oxyeleotris lineolatus (♀) × O. marmorata (♂)Fan et al. (2009)
Oreochromis niloticus (♀) × O. aureus (♂)Yang et al. (2006)
Oreochromis mossambicus (♀) × O. hornorum (♂)Yang et al. (2006)
Oreochromis aureus (♀) × Sinipperca chuatai (♂)Yu et al. (2003)
Oreochromis mossambicus (♀) × O. niloticus (♂)Liu et al. (1985)
Oreochromis aureus (♀) × O. niloticus (♂)Xia et al. (1999)
Oreochromis niloticus (♀) × Sarotherodon melanotheron (♂)Yan et al. (2007)
Sarotherodon melanotheron (♀) × Oreochromis niloticus (♂)Yan et al. (2007)
Lepomis cyanellus (♀) × Lepomis macrochirus (♂)Chen and Su (2006)
Perca flavescens (♀) × P. schrenki (♂)Ding et al. (2012)
Hephaestus fuliginosus (♀) × Scortum barcoo (♂)Lu and Wang (2010)
Paralichthys olivaceus (♀) × P. dentatus (♂)Guan et al. (2007)
Paralichthys lethostigma (♀) × P. dentatus (♂)Gong (2009)
Fugu flavidus (♀) × F. rubripes (♂)Fan et al. (2011)
Oncorhynchus mykiss (♀) × O.kisutch (♂)Xu et al. (2006)
Oncorhynchus mykiss (♀) × Oncorhynchus masou masou (♂)Zhang et al. (2009)
Cyprinus carpio var. specularis (♀) × Megalobrama amblycephala (♂)Jin et al. (2003)
Carassius auratus cuvieri (♀) × Cyprinus carpio var. specularis (♂)He et al. (1995)
Carassius auratus cuvieri (♀) × Cyprinus carpio var. singuonensis (♂)Chen (2000)
Carassius auratus auratus (♀) × C. auratus cuvieri (♂)Lou et al. (1995)
Cyprinus carpio var. wananensis (♀) × C. carpio var. specularis (♂)Chi et al. (2010)
Cyprinus carpio var. specularis (♀) × C. carpio var. wananensis (♂)Chi et al. (2010)
Cyprinus carpio var. mirror (♀) × C. carpio var. specularis (♂)Liu et al. (1993)
Cyprinus carpio haematopterus (♀) × C. carpio var. mirror (♂)Ge et al. (2012)
Cyprinus carpio var. mirror (♀) × C. carpio haematopterus (♂)Ge et al. (2012)
Cyprinus carpio var. singuonensis (♀) × C. carpio var. mirror (♂)Dong et al. (1999)
Cyprinus carpio var. mirror (♀) × C. carpio var. singuonensis (♂)Dong et al. (1999)
Clarias macrocephalus (♀) × C. fuscus (♂)Wu et al. (1990)
Clarias fuscus (♀) × C. lazera (♂)Wu et al. (1990)
Clarias lazera (♀) × C. fuscus (♂)Zhang (1989)
Clarias macrocephalus (♀) × C. lazera (♂)Wu et al. (1990)

For domestic transfers, both the number of individuals and total value of transferred species are extremely large. For example, only in Hongdao, a coastal town in Qingdao city, Shandong Province, the total value of introduced seed of Ruditapes philippinarum and Sinonovacula constrictais is more than 100 million Chinese Yuan (more than US$ 16 million) per annum (Liu 2005; Liu et al. 2007a). For the fresh water system, lakes in Yunnan Province represent well-known examples. Starting in 1958, the four major Chinese carps (black carp Mylopharyngodon piceus, grass carp Ctenopharyngodon idellus, silver carp Hypophthalmichthys molitrix, bighead carp Aristichthys nobilis) were introduced into major lakes in Yunnan Province. The introduction and release scale are extremely large, for example, the total number of released individuals of these four carp species reaches more than four million per annum in Lake Dian (Chen et al. 1998).


Established species may spread widely and become invasive at new locations (i.e. biological invasions), sometimes after a lag phase of many years in which populations remained small and localized (O'Dowd et al. 2003; Jeschke & Strayer 2005). Among 179 species introduced internationally into China, 17 (9.5%) have had negative effects on local environments (Table 1 and references therein). These negative effects include ecosystem degradation (e.g. sea grass beds destroyed by the Japanese sea urchin Strongylocentrotus intermedius, Liu et al. 2007a), loss of biodiversity and even species extinction (e.g. devastating predation on native amphibians by the bull frog Rana catesbeiana, Li & Xie 2004), and faunal homogenization (e.g. the red-bellied piramha Pygocentrus nattereri become dominant in many water bodies by excluding/killing/eating almost all native species, Li et al. 2007a). Moreover, some invasive species are associated with economic impacts, including increased operating costs (e.g. fouling by the Pacific oyster Crassostrea gigas, Sun et al. 2010) and lost revenue (e.g. agriculture crops destroyed by the apple snail Pomacea canaliculata, Li et al. 2007a). Although other species have not had detectable negative effects, risks may still remain due to a lag phase of biological invasions.

When compared with the international transfer of non-native species, domestic translocation may possess even higher risks, mainly owing to easy transfer, time- and cost saving, a large number of propagules involved, and importantly lack of restriction regulations. The introduction of fish from the Yangtze River drainage into major lakes in Yunnan Province plays one of the most important roles for the loss of biodiversity. Yunnan Province is a hotspot of biodiversity for freshwater fish in China, with more than 430 endemic species in this province (Chen et al. 1998). Lake Dian, which is the biggest lake in Yunnan Province, had 23 native species based on historical records, 11 of which are endemic to this lake. After the introduction of fish from the Yangtze River drainage, especially the four major Chinese carps, the number of native species decreases extremely fast: from 23 to 15 in 1978, to eight in 1982, to two in 1997, and only one in 2007–2008, and all endemic species become extinct (Chen et al. 1998; Yuan et al. 2010). By contrast, both the number of non-native species and population size sharply increase. For example, 93.8% of species is non-native in Lake Dian in the survey conducted in 2007–2008 (Fig. 6). This decrease in native species and increase in non-native species also happened in other major lakes in Yunnan province. For example, the production of fish in Lake Erhai increased from less than 2500 ton in 2001 to more than 5000 ton in 2009, and all major captured fish were non-native (Fei et al. 2011). All endemic species in 7 of 9 lakes surveyed are extinct, and the majority of fish species in these lakes are non-native (Fig. 6). Although many factors, such as overfishing, reclamation of land from lakes, dam construction, pollution, and others may contribute to such loss of biodiversity (Chen et al. 1998), the fact is that both the number and production of non-native species increase. All evidence suggests that the introduction of non-native species plays a role for such loss of biodiversity.

Figure 6.

Number of species in different categories, including native, non-native and local endemic, in nine major lakes in Yunnan Province based on both historical records and survey conducted in 2007–2008 (bar chart), and proportion of native and non-native species in each lake in the survey of 2007–2008 (pie chart). Arrows indicate that all endemic species have been extinct based on the data from 2007–2008 survey. All data from Yuan et al. (2010).

Management solutions

A clear policy on the introduction of non-native species is needed as aquaculture expands, especially in developing countries. The policy must be clearly made based on the principle that all species are considered potentially harmful and therefore forbidden for introduction unless risk of invasiveness is acceptably low. The ICES Code of Practice on the Introductions and Transfers of Marine Organisms recommends effective procedures and practices to diminish potential risks. The most up-to-date version of this Code, published in 2005, covers all concerns expressed in former versions and follows the precautionary approach adopted from the FAO principles with the goal of reducing the spread of exotic species (ICES 2005). The ICES Code has become a well-recognized instrument, and its essential components have been widely applied to the evaluation of species introductions.

Based on ICES Code, essential components for a sound management programme include the following:

  1. Using multiple discipline procedures and the state-of-the-art technologies for scientific risk assessment and strictly applying a well-evaluated programme to every species proposed for introduction; this is the first priority to stop introductions of harmful species into local environments. Risk assessment relies on scientific methodologies to support decision-making. Methodology successfully developed for the Weed Risk Assessment (WRA, Pheloung et al. 1999) provides a good model to follow-up for the risk assessment of the introduction non-native aquatic species. Indeed, models and tools focusing on different taxonomic groups, such as Freshwater Fish Invasiveness Scoring Kit (FISK) and Marine Invertebrate Invasiveness Scoring Kit (MI-ISK), have been successfully developed based on WRA, and all these tools are made freely available at Centre for Environment, Fisheries & Aquaculture Science (Cefas) website ( Such tools and models can be adopted, modified and evaluated under various circumstances, such as characteristics of different species and different condition of water bodies.
  2. Developing new cost-effective tools (such as those based on remote sensing and global positioning system technologies) to monitor introduced species in order to rapidly respond to newly emerged negative effects; this serves as a supplement of recommendation (1) to response to problems caused by those not blocked by the procedure of risk assessment. Indeed, remote-sensing and global–positioning system technologies have been successfully used for detecting and mapping of invasive species, including aquatic invasive species (e.g. Maheu-Girouxa & de Blois 2005). These provide good successful examples to follow-up for other species, although technical questions remain to be solved for wide application.
  3. Establishing a legal authority specifically to perform comprehensive risk assessment and to monitor introduced species, especially those having high probabilities to escape, or to be released and discarded into local water bodies. In addition, such a legal authority should be responsible for providing research-based strategic management advice, such as (i) scientifically assessing culture methods (e.g. open versus enclosed) based on biological characteristics of transferred species and environmental conditions of different water bodies (e.g. coastal region, inland lakes, etc.); (ii) establishing a species-specific parameter for the number of escapees, that is a threshold for the establishment of self-sustaining populations and/or prevention of genetic changes to natural local populations, and subsequently using this parameter to strictly monitor escapees and all release events; (iii) developing sterile stains of transferred species/populations using safe manipulations.

In addition, sound management on non-native species used for aquaculture requires international effort, coordination and collaboration, mainly because some countries have less strict or no regulations on the introduction and use of non-native species. Negative impacts occur in such countries might spread larger areas, finally affecting neighbouring countries. The hazardous Substances and New Organisms Act (1996) implemented in New Zealand provides a common model that other countries could follow. Under this act, importers of non-native species must apply to an independent regulatory authority accountable to the Environment Ministry and Parliament for public approval.

Fellow travellers, accidental introductions


Fellow travellers, or hitchhiking species, refer to species that inadvertently accompany the shipment of the species intended for introduction/transfer. Many countries have a long history of importing species for aquaculture and live aquatic products from regional, national and international sources (De Silva et al. 2009; Peeler et al. 2011; De Silva 2012). Fellow travellers, attaching to the surface or inside of the body (e.g. gut, lung and mussel) of these desired species, are introduced into local environments, where they may become invasive and cause huge economic and environmental damages. For example, the European green crab (Carcinus maenus), a voracious predator and aggressive colonizer, is believed to have been introduced to the U.S. west coast in packing materials (seaweeds) of live food fish from the east coast (Yamada & Gillespie 2008). This crab species has had a strong influence through predation and aggression on biodiversity in invaded ranges (Grosholz & Ruiz 1995; Jamieson et al. 1998).

Fellow travellers in China

Despite the fact that micro-organism may be the major group of fellow travellers, we could not make a list in this review, mainly due to difficulties to track origins and poor historical records worldwide. Besides pathogens, a total of three species have clear records as fellow travellers (Table 1), two of which belong to brown algae (Costaria costata, Desmarestia ligulata), and the remaining one is red algae (Trichogloea lubrica; Table 1). All these three species were unintentionally transferred into China along with the introduction of Undaria pinnatifida from Japan (see Table 1 and references therein). It should be noted that the number of fellow travellers can be much larger than what we have known so far, because many fellow travellers remain inconspicuous at subthreshold densities.


One of the known examples in China is Desmarestia ligulata, which has become a harmful species in northern China after the introduction along with an aquaculture species Undaria pinnatifida. The length of this species usually reaches 1 m in China, which is much longer than 30–50 cm in its native ranges (Liu et al. 2007a). This brown algae release sulphuric acid after death, which can highly increase acidity of sea water. It is well known that ocean acidification has significantly negative impacts on marine ecosystems (see review by Fabry et al. 2008). An outbreak of this species not only can influence local water bodies in China, but also might threaten neighbouring areas after acid is advected and spread by marine currents in ‘open’ oceans.

Management solutions

Fast and correct identification of fellow travellers before introduction represents the first and also most important step for the prevention of introduction of undesired harmful species. For large fellow travellers, especially those attached on body surface, identification might not be difficult, because large organisms could be easily detected by eye inspection and then eliminated. However, for small organisms such as micro-organisms and those at particular life stages such as eggs and immature individuals, huge challenges remain for fast and correct identification, not only because it poses immense technical difficulties to identify numerous extremely small organisms, but also a large number of micro-organisms often are unidentified hazards (e.g. Whittington & Chong 2007; Peeler et al. 2011). Unfortunately, currently applied risk assessment usually does not account for unidentified hazards.

There is little double that so far routine quarantine inspection has been the major method for the prevention of introduction of fellow travellers. Besides routine quarantine inspections and exams, several more recommendations can reduce/eliminate risks caused by fellow travellers: (i) introduction of fertilized eggs, instead of adults, should be encouraged to reduce the number of potential fellow travellers; (ii) it is essential to develop high-throughput and effective inspection tools, especially genetic tools based on newly emerged technologies, such as gene probe, microarray, and highly sensitive tools such as 454 pyrosequencing to effectively detect small organisms and low-density populations (Zhan et al. 2013). Indeed, some of these DNA-based methods have been available, pending only the initiative and investment of time and money to tailor tools to specific tasks (See reviews by Darling & Blum 2007; Darling & Mahon 2011). In addition, it should be noted that the impending benefits of DNA/RNA-based methods are vast, and worthy of continued effort and investment (Darling & Blum 2007; Darling & Mahon 2011).

Artificial hybridization


Intra- and inter-specific hybridizations are widely employed in breeding programmes to improve economic properties of aquaculture species, that is, to obtain hybrid vigour or positive heterosis such as growth rate, disease resistance, harvestability and environmental tolerance (Bartley et al. 2001; Hulata 2001). Hybridization possesses many obvious advantages including simplicity of operation, time-saving, and immediate and significant improvement on performance of desired traits (Hulata 2001). Successfully created hybrids constitute a significant proportion of aquaculture production in several countries, such as hybrid striped bass (Morone chrysops × M. saxatilis) in the USA (Carlberg et al. 2000), hybrid catfish (Clarias gariepinus ×C. macrocephalus) in Thailand (De Silva et al. 2006), and hybrid tilapia (Oreochromis niloticus × O. aureus) in Israel (Milstein et al. 2001). Owing to these advantages, a large proportion of introduced non-native species is subjected to hybridization practice (see reviews by Bartley et al. 2001; Hulata 2001; Lou & Li 2006).

Hybridization practice in China

Hybridization is one of the most common practices in various breeding programmes in China. For intra-specific hybridization, it is common that different geographical populations of a species are introduced into local places where this species naturally occurs. One of the well-known examples is the introduction of Japanese stocks of the Pacific abalone (Haliotis discus hannai) into northern China to resolve the high-mortality problem (>90%) caused by diseases in 1994 (Zhang et al. 2004). The hybrids between Chinese and Japanese stocks, which highly improved survival rate (approximately 100%) and growth rate (approximately 30%), saved the abalone industry in China (Guo 2009).

For inter-specific hybridization, large-scale trials have been conducted both between native species and non-native species, and between two non-native species (Table 2). So far, at least 43 (24%) non-native species introduced internationally have been successfully subjected for inter-specific hybridization, yielding at least 63 successful crosses in echinoderms (1 cross), mollusks (14 crosses), algae (2 crosses) and fish (46 crosses; Table 2). Among these successful crosses, one of the successful examples is hybridization between two non-native species of sea kelps, Laminaria japonica and L. logissima, which were introduced from Japan in 1990s. Based on these two non-native species, more than ten varieties have been created and proven as new varieties with improved economic traits by the National Appraisal Committee of Aquatic Protospecies and Improved Varieties. The Dongfang No.2 (L. longissima ♀ × L. japonica♂) variety improved yield more than 25% when subjected to large-scale cultivation at different locations (Li et al. 2007b). Now, almost all farmed kelps in China are hybrids.


Risks caused by hybrids are mainly genetic pollution (e.g. loss of genetic variation, breakdown of population structure) and species extinction (Huxel 1999; Bartley et al. 2001; Hails & Morley 2005). The observed diversity and distributions of species are formed by millions of years of evolution. Geographical isolation prevents hybridization and introgression, and species or local populations have been well adapted to local environmental conditions. Aquaculture and related activities bring species into contact with their relatives from which these species have been historically isolated, and then further seek possible ways to produce hybrids with positive heterosis. In the absence of hybridization, invaders might be quickly eliminated due to low population density (i.e. Allee or stochastic effects). However, in the presence of hybridization, especially human-mediated hybridization aiming to produce vigourous offspring, non-native genetic materials could rapidly introgress into native gene pools, leading to genetic pollution to local populations and/or replacement of local gene pools. Using mathematical simulations, Huxel (1999) found that displacement of native gene pools could occur very rapidly: less than five generations. Indeed, quick replacement of local gene pools caused by both intra- and inter-specific hybrids has been observed in aquaculture species in China. The Pacific abalone (Haliotis discus hannai) in northern China and carps (genus Cyprinus) in Yunnan province represent good examples for intra- and inter-specific hybrids, respectively. As mentioned previously, hybrids between Chinese and Japanese stocks of the Pacific abalone successfully saved abalone aquaculture industry in the late 1990s in China; however, after several generations farming, 84.1% of individuals collected from the wild in northern China was identified as hybrids based on molecular markers and corresponding analyses (Wang 2011). Similarly, almost all carps from Lake Xingyun in Yunnan province are inter-specific hybrids, as revealed by both morphological and genetic surveys (Yang et al. 2011). ‘Pure'native species do not exist in the wild, that is, species extinction genetically, the worst consequence caused by aquaculture-mediated hybridization. This type of extinction, which is different from ‘traditional extinction’ (i.e. permanent disappearance of a species), is largely ‘invisible’ to the human eye and cannot be detected without detailed investigations based on molecular analyses, leading to difficulties to generate an understanding in the public. Owing to a high rate of human-mediated introductions and hybridizations, Huxel (1999) suggested that hybridization alone may become a major cause for species extinction.

Management solutions

Although empirical studies have shown that some aquaculture-mediated hybrids are threatening local environments and biodiversity, there is still a lack of comprehensive programmes/systems for risk assessment and sound management of farmed hybrids. Several recommendations should be considered before hybrids are practically adopted and widely farmed. (i) Risk assessment, especially probabilities to breed with parental species and relatives in local surrounding environments, must be carried out, and the results are used to develop species-specific (e.g. based on unique biological, genetic, physiological characteristics of each hybrid and parental species) and case-specific (e.g. intra- or inter-specific hybridization) performance standards. Although genetically modified organisms (GMOs) are defined by the international community and national governments as organisms created by recombinant DNA technologies, indeed, inter-specific hybridization represents a genetic modification wherein genetic materials from different species are combined in a single species (see review by Bartley et al. 2001 and references therein). The debate on whether or not inter-specific hybrids are GMOs is beyond the scope of this review, but risks caused by inter-specific hybrids may be as high as GMOs (Bartley et al. 2001). Consequently, risk assessment programmes for GMOs (e.g. Hill 2005) should be also applied to inter-specific hybrids, even to intra-specific hybrids, to approve whether or not these hybrids are environmentally safe enough to be widely farmed in aquaculture. (ii) Proper management of hybridization depends on knowledge of basic background of crossing, such as biological and genetic characteristics of parental species and resulting offspring hybrids, mechanisms of positive heterosis, genotype × environment interactions, etc. Consequently, intensive research should be performed to clarify these fundamental questions. According to the information obtained from these two recommendations, optimized management measures including culture method, facility design and operation management of the whole grow-out procedure should be advised and strictly followed by aquaculture managers. (iii) An oversight authority should set up surveillance programmes to monitor hybrids and launch quick response programmes for newly emerged negative effects.

Mass release of non-native species for ranching


Mass release for ranching is a form of extensive aquaculture. Ranching refers to the release of cultured juveniles into unenclosed environments for harvest at a larger size in ‘put, grow and take’ operations (Bell et al. 2008). Now large-scale mass release of non-native for ranching has been performed for many aquaculture species in many countries (Shelton & Rothbard 2006). For example, approximately one-third of the capture harvest in the Caspian Sea was derived from stocked fish (Shelton & Rothbard 2006). Such aquaculture also supports important industries. For example, the caviar industry in the Black and Caspian Seas was maintained for decades by ranching transplanted sturgeon (McNeil 1979). Although mass release for ranching has been proven to have immediate improvement on aquaculture production, adverse effects on local environments and native biodiversity are largely neglected in research and policy (Laikre et al. 2010).

Mass release of non-native species for ranching in China

Since the 1980s, large-scale release is intentionally performed in almost all major marine and freshwater water bodies in China (Li 2011; Tao & Wang 2011). The number of both species and released individuals increased rapidly in the past decade. Nationwide, the total number of released individuals increased from 8.9 billion in 2005 to 19.46 billion in 2007, while the value increased from 1.29 to 2.64 billion Chinese Yuan (Li 2011). Based on the National General Plan of Mass Release and Stock Enhancement for Aquatic Organisms (2011–2015), more than 34 billion individuals derived from 167 species are planned to be released into 356 water bodies in 2015. Species used for mass release for ranching in China are of three categories: (i) highly valued aquaculture species, including both native and non-native, of which native ones are the most commonly used in China; (ii) rare and endangered species; (iii) local-endemic species. Despite that the number of species and release scale for non-native species are not as large as those for native species, non-native species, which cover all major aquaculture species categories, have been successfully released for ranching, for example, mollusks such as the Japanese scallop Patinopecten yessoensis, echinoderms such as Japanese sea urchin Strongylocentrotus intermedius, fish such as turbot Psetta maxima, and crustaceans such as black tiger prawn Penaeus monodon and white-leg shrimp Penaeus vannamei.


High debate on the merits of large-scale release for ranching increases as the interest of such performance grows in aquaculture (see review by Mustafa 2003). Mass release poses the highest risk for the establishment of populations, mainly owing to a large number of individuals involved and direct release into suitable habitats. Sometimes establishment of populations in the wild may be beneficial to aquaculture; however, once non-native species become established, it is very difficult to control them (see review by Tyus & Saunders 2000). Established non-native species may become harmful after successfully localized. One representative example in China is the Japanese sea urchin Strongylocentrotus intermedius (Liu et al. 2007a). The established sea urchin populations have threatened local environments and biodiversity, such as destroying seaweed bed and aquaculture facilities, and competing with native species for food and space (Liu et al. 2007a).

Management solutions

Although mass release of aquaculture species in many countries is partially organized and/or supervised by local or central/federal governments, unfortunately scientific assessment was seldom employed to direct such large-scale releases. Assessment of risk-benefit trade-offs prior to mass release has proven to be most effective way for decision-making (Waples & Drake 2004; Barbour et al. 2008). Studies have indicated that taxa-specific risk-benefit assessment protocols are needed (Waples & Drake 2004; Barbour et al. 2008). To make effective taxa-specific assessment protocol, research gaps should be filled for species proposed to release, such as what is the observed and expected genetic structure of local populations before and after mass release respectively, how are individuals chosen to minimize genetic change to local populations, and what are biological and environmental consequences after release and how are these consequences properly assessed. All obtained information, including that derived from recommendations for risk assessment and management for each category of species, risk-benefit assessment and research results should be systemically combined and implemented into monitoring programmes. Finally, monitoring programmes need to be linked with management policy to point out outcomes from both mass release and associated monitoring, and management solutions/actions for each outcome.


Our dependence on non-native species for aquaculture likely becomes greater in the future as it supports increasing demands in aquatic food markets. It is therefore expected that the introduction and/or use of non-native species is more frequent and a common practice in aquaculture. For a practical and realistic perspective, sound management, coupled with good knowledge of possible risks and well prepared solutions for such negative effects, is the way for sustainable development of aquaculture. However, the aquaculture industry must now face the fact that accelerating introduction and/or use of non-native species for aquaculture remain unthoroughly unregulated, especially in developing countries, leading to high risks to ecosystems, economies, and even public health of inhabitants. Recent research adds increasing evidence on negative effects, threats and risks, which has fed back to affect sustainable development of aquaculture. In this review, we discuss observed and potential risks associated with unregulated introduction and irresponsible use of non-native species and recommend solutions for management based on high-risk aquaculture activities and related events employed in the past several decades.

The lack of risk assessment and sound management for non-native species is particularly true for the sustainable development of aquaculture, although risks and negative effects have been recognized and repeatedly stressed in literature in the past decades. Lessons from known disasters caused by non-native species are slowly learned compared with outbreak scale and spread speed of disasters. Numerous reasons are responsible for such slow pace, and the most important one is that short-term benefit is concentrated and long-term development is highly neglected. In addition, the aquaculture industry is the beneficiary of introductions of non-native species, but aquaculture industry is not made to pay the costs of environment damage once non-native species become invasive.

We stress that there is an extremely urgent need to consider risk assessment and sound management for the introduction and use of non-native species as aquaculture fast expands. Without proper management, negative effects can go extremely high degrees and large geographic scales, and in return, will certainly affect the sustainable development of aquaculture, and even lead to severe disasters to aquaculture. Meanwhile, we also suggest that policies should be put in place to make aquaculture industry pay for environmental damage. Finally, we call for effort and collaboration of researchers from academia, government and industry for responsible introduction and use of non-native species.


This study was supported by National Natural Science Foundation of China (No. 31272665) and “100-Talent Program“ of the Chinese Academy of Sciences to A.Z.