Use of Larvivorous Fish in Biological and Environmental Control of Disease Vectors - Biological and Environmental Control of Disease Vectors - page 26

synthetic insecticides, biocontrol agents can be
host- and target-specifi c, are perceived safer to
the environment due to their biodegradability,
and have little evidence of resistance
development in target mosquito species. The
biological resources that can perform as
predators of mosquito larvae are taxonomically
diverse, as described in Chapter 2 (this volume).
Here, we concentrate on the use of predatory
larvivorous fi sh as control agents of mosquito
larvae. Approximately 315 larvivorous fi sh
species belonging to 32 genera under seven
families are recorded. The family Cyprino-
dontidae contributes the highest number of
genera (15) and species (300), followed by
Cyprinidae, Hemirhamphidae, Chilidae, Good-
eidae, Poeciliidae and Anabantidae (Ghosh and
Dash, 2007).

Gerberich and Laird (1968) reviewed the present
status of the application of larvivorous fi shes
and reported the potential use of about 250
species of fi shes for the control of mosquitoes.
Larvivorous fi sh have been successfully exploited
for mosquito control in various parts of the
world such as southern Europe, northern
Africa, Soviet Georgia, India, Iran, New Guinea,
Malaysia and Madagascar (Bruce-Chwatt,
1985), but have been found to be mostly ef ective
in temperate and tropical countries with high
rates of mosquito-borne diseases. However, their
application has so far been on a general and ad
hoc basis, and limited to laboratory evaluations
without adequate systematic monitoring and
applications in dif erent fi eld conditions

(Motabar, 1978).
Recognizing the high larvivorous potential
of G. ai nis , this fi sh species was purposefully
introduced from its native Texas (southern USA)
to other parts of the world in 1905 (Gerberich
and Laird, 1985).

3.2 Mosquito Control by Larvivorous
Fish

In 1908, another larvivorous
fi sh, Poecilia reticulata , native to South America,
was introduced to British India and many other
countries for malaria control. Below, we describe
the feeding capabilities of other larvivorous fi sh,
considering their habitat sharing with the target
mosquito species (WHO, 2003b; Chandra et al .,
2008a). Fish may be particularly useful in
controlling vector mosquitoes in rice fi elds (Lacey
and Lacey, 1990). In Asia, introduction or
management of larvivorous fi sh has been ef ective
where pisciculture can provide additional
economic, agricultural and nutritional benefi ts
(Gupta et al ., 1989; Wu et al ., 1991; Victor et al .,
1994). In China, Wu et al . (1991) found that
stocking rice paddies with edible fi sh, such as carps,
improved rice yield, supported fi sh production and
greatly reduced the number of malaria cases.
Thus, the use of larvivorous fi sh in regulating
mosquito populations yielded a dual benefi t by
reducing the number of mosquitoes and by gaining
economically through aquaculture.
The use of larvivorous fi sh is one of the
oldest practices in vector control, and currently
a popular biological control agent for reducing
mosquito populations. Larvivorous fi sh have
several benefi cial characteristics for mosquito
control, which include: after their introduction
and establishment they are self-perpetuating
and continue to reduce mosquito larvae for long
periods of time; the cost of controlling mosquito

Application of fi sh for the control of larval stages
of insects including mosquitoes was practised
from the beginning of the 19th century. The
earliest reference of the fi eld application of
larvivorous fi sh came from the application of
Lebistes reticulatus in all rain barrels examined in
the inlands of Barbados during 1905 (Howard et
al ., 1912), where it was practised for generations.
Natives of South America often introduced
minnows in barrels, tubs, tanks and other
artifi cial containers around their homes. The
indigenous tribes of Central American Indians
have also kept fi sh called Nundo locally in water
containers and tanks for the control of mosquito
larvae. Use of fi sh for mosquito control in open
shallow wells to keep down the number of
mosquitoes and 'purify the water' was practised
in the USA from 1900. Gambusia ai nis was
introduced into the Hawaiian islands in 1905
from its native Texas to examine its ei cacy
against mosquito larvae (Seale, 1905). Sub-
sequently this fi sh was introduced in other parts
of the world.
About 40 dif erent biocontrol agents have
been reported to be used for the control of
mosquito larvae in aquatic water bodies, and
several fi sh species have shown great promise for
development in operational control strategies
against vector species (Wu et al ., 1987).