Role of Fish as Predators of Mosquito Larvae on the Floodplain of the Gambia River

Abstract

We examined the potential of using native fish species in regulating mosquitoes in the floodplain of the Gambia River, the major source of mosquitoes in rural parts of The Gambia. Fishes and mosquito larvae were sampled along two 2.3-km-long transects, from the landward edge of the floodplain to the river from May to November 2005 to 2007. A semifield trial was used to test the predatory capacity of fish on mosquito larvae and the influence of fish chemical cues on oviposition. In the field, there was less chance of finding culicine larvae where Tilapia guineensis, the most common floodplain fish, were present; however, the presence of anophelines was not related to the presence or absence of any fish species. In semifield trials, both T. guineensis and Epiplatys spilargyreius were effective predators, removing all late-stage culicine and anopheline larvae within 1 d. Fewer culicines oviposited in sites with fish, suggesting that ovipositing culicine females avoid water with fish. In contrast, oviposition by anophelines was unaffected by fish. Our studies show that T. guineensis is a potential candidate for controlling mosquitoes in The Gambia. KeywordsAnopheles gambiae; fish; mosquitoes; predation; oviposition The use of fish for controlling mosquitoes was an important tool in the pre-DDT era (Floore 2006, Walker andLynch 2007). Typically fish were introduced into all potential mosquito breeding habitats, including ricefields, marshes, dams, canals, and ponds (Hadjinicolaou and Betzios 1973, Motabar 1978). However, the introduction of DDT in the mid-1940s led to a significant decrease in the use of biological control (Gabaldon 1969). Nevertheless, after concerns regarding the harmful effects of chemicals on nontarget species and the development of insecticide resistance by mosquitoes (Milam et al. 2000), interest in the biological control of malaria vectors has been rekindled (Killeen et al. 2002, Killeen 2003.Fish have been used successfully for controlling both culicine and anopheline mosquitoes (Tabibzadeh et al. 1970, Victor et al. 1994 but are used relatively infrequently in sub-Saharan Africa (Walker and Lynch 2007). Mosquito control using fish has focused on a limited number of species, primarily Gambusia affinnis Baird and Girard and Poecilia reticulata Peters, that have traditionally been used for controlling mosquito larvae (Sitaraman et al. 1975, Gall et al. 1980, Cech and Linden 1987, Homsky et al. 1987, Blaustein 1992, Valero et al. 2006, Walton 2007. One of the most important concerns when introducing exotic fish for mosquito control is their impact on native species (Benigno 2001, Hoddle 2004. In Greece, the introduction of G. affinis led to a decline of the endemic fish species Valencia letourneuxi Sauvage 1Corresponding author, vasilis.louca@durham.ac.uk. 1978, Arthington 1991, Garcia-Berthou 1999, Leyse et al. 2004). The problems with introducing exotic species have spurred interest in the use of native species for controlling mosquitoes (Romand 1985;Mancini and Romi 1988;Fletcher e...

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Do Chenopodium ambrosioides-Synthesized Silver Nanoparticles Impact Oryzias melastigma Predation Against Aedes albopictus Larvae?

“…Indeed, the natural enemies feeding on mosquito larvae and pupae in aquatic environments play an important role in reducing Culicidae populations (e.g. [65,131,136]. Larvivorous fishes are being successfully exploited for control of mosquito vectors aquatic stages in European, Asian, African and Arabian countries [21,65].…”

“…[65,131,136]. Larvivorous fishes are being successfully exploited for control of mosquito vectors aquatic stages in European, Asian, African and Arabian countries [21,65]. Moreover, the larvivorous fishes provide dual benefits by reducing the mosquito populations and indirectly augmenting the aqua cultural economics [26,73,114,132]; see [17] for a recent review).…”

Potential negative impacts and low effectiveness in the use of African annual killifish in the biocontrol of aquatic mosquito larvae in temporary water bodies

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