WWW.WAS.ORG • WORLD AQUACULTURE • JUNE 2018 61 (CONTINUED ON PAGE 62) for Conservation of Nature are from aquarium or ornamental releases (Lowe et al. 2000). The glaring prevalence of aquarium fish as the greatest number of local IAFS necessitates an inquiry of the degree of involvement of the Philippines in ornamental fish trade. Is Ornamental Fish/Aquarium Trade the Culprit? One of the primary reasons for ornamental IAFS is the thriving and unregulated aquarium trade industry with consequent and unwanted species invasions from increased commercial activities. The ornamental and aquarium trade represents a large reservoir of invasive species with around 115 invasive freshwater fishes introduced globally (Mendoza et al. 2015). Despite the risks, the Food and Agriculture Organization (FAO) promotes the ornamental fish sector for development in terms of poverty alleviation and marine preservation in rural communities (Padilla and Williams 2004). This is mirrored in the Philippines by promotional activities of the Bureau of Fisheries and Aquatic Resources (BFAR) from as early as 2005, being part of its short-term plan to reduce imports and increase exports of high-value ornamentals using backyard fishpond and tank aquaculture methods (PhilStar Global 2005). The business is lucrative, with ornamentals fetching prices of US$ 395/kg, in comparison to Nile tilapia that sells for US$ 1.58/kg (PDI 2017). Ornamental fish farming is on the list of sustainable development and trends in Philippine aquaculture (Lopez 2006) and this trend continues. Until recently, BFAR has been providing broodstock and training for those interested in ornamental fish farming (PDI 2017). Stemming from good intentions at augmenting the income of lower and middle-class families, the lack of strict implementation of rules regarding the rearing and trade of ornamental fish may be a possible route of infestation of local waters. Actual reports of Philippine exotic IAFS trade prevalence are very limited, despite numerous sales in several small-scale aquarium shops in Manila. The interest in ornamental fish export is not without reason. From 1976 to 2007, the number of countries involved in the ornamental fish trade has been increasing, and according to FAO data, export volume value increased from US$ 21.5 million in 1976 to US$ 315 million in 2007 (Monticini 2010). Asia exports about US$ 162 million worth of ornamental fish species, comprising 51 percent of the global ornamental fish trade. The Philippines alone exports about US$ 7.4 million worth of ornamental species, with a 2.3 percent global export share as of 2007 (Monticini 2010). The sheer number of fish transported from one region to the other, including exports from and to the Philippines may be another possible venue for accidental release of IAFS when proper monitoring is scarce. This may be increasingly true for small backyard farms and aquarium shops without proper aquaculture risk management strategies. However, the extent of IAFS invasion in the Philippines, occupying discrete bodies of water, points to several drivers for their territorial expansion. Pathways for Invasion by Ornamentals The two major pathways for IAFS ornamental colonization of waters are intended or accidental introduction. Freshwater fishes are some of the most heavily introduced aquatic animals globally (Gozlan 2008). Direct introduction maybe through attempted breeding in freshwater catchments; broodstock rearing in open, inland waters; and introduction into lentic and lotic systems. Despite the demand for fish and fish products varying from country to country, global societal demands for ornamentals may account for up to 21 percent of all intended introductions (Gozlan 2008). In the Philippines, information on the history of intended introductions is scarce, except those primarily intended for food production and recreation (Joshi 2006), with minimal knowledge of possible ecological impacts of their introduction (Guerrero 2014). Although only a few species that escape have the potential to be invasive (Keller et al. 2007), there is a growing concern for impacts of ornamental fish introduction due to a lack of data on the full environmental and economic cost of ornamental escapees (Padilla and Williams 2016). The costs of production losses are difficult to quantify because accurate estimates of losses of commercially important fishes are difficult to measure. Although there are minimal records on the accidental release and dispersal of fishes worldwide (Copp et al. 2005), ornamental fish have the greatest potential to be introduced into freshwater ecosystems (Duggan et al. 2006). The dumping of ornamentals into new waters is a major route of IAFS reaching new ecosystems (Magalhães and Jacobi 2013). Fragile aquatic habitats are most hit by IAFS travelling via the aquarium trade (Knight 2010). One major accidental route of IAFS dispersal that needs further study in the Philippines is the impact of the 15-16 typhoons the country experiences annually (FAO 2014). Typhoons may cause flooding that can facilitate the escape of ornamentals from backyard aquaculture farms and contained bodies of water, such as in the case of ornamental knifefish C. ornata. This knifefish was believed to have been introduced into Laguna de Bay two years after the massive flooding caused by Typhoon Ondoy in 2009 (Guerrero 2014). The common or leopard Walking catfish Clarias batrachus are easily captured from various inland waters of Central Luzon, Philippines. Photo: Joebelle Mercado Ramirez. Jaguar cichlid Parachromis managuensis captured as a fingerling from Taal Lake, Batangas, Philippines and kept as an indoor pet. Photo: Zomesh A. Maini.
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