Blue revolution goes awry

AQUACULTURE, once eulogised as a trouble-free money-spinner, is now causing
sleepless nights for its promoters. Last
year, a mysterious viral disease, nick-
named "white spot", had swept Tamil
Nadu, Andhra Pradesh and Kerala, decimating a large part of the cultured
shrimp crop. After ravaging the industry
in West Bengal, the scourge has recently
affected the prawn farms of Karnataka's
Uttar Kannada district. The genesis of
the outbreak has been traced to infected
prawn seeds released by an aquaculture
company in the Aghanashini river. The
disease has left farms in the district's
Kumta taluk, through which the river
flows, full of dead prawns. The aquaculture industry in other Asian nations is
similarly afflicted. Taiwan, the world's
largest shrimp exporter till a few years
ago, has seen its output fall from 90,000
metric tonnes (mt) in 1987 to 25,000 mt
in 1989 owing to a disease-hit industry.
Experts say intensive production, too
rapid an expansion, overexploitation of
groundwater and self- contamination of
the water in the farms have led to the outbreaks.