Mekong dolphins on the brink of extinction The Mekong River
Irrawaddy dolphin (Orcaella brevirostris) population inhabits a
190km stretch of the Mekong River between Cambodia and Lao PDR.
Since 2003, the population has suffered 88 deaths of which over
60 percent were calves under two weeks old. The latest
population is estimated between 64 and 76 members. "Necropsy
analysis identified a bacterial disease as the cause of the calf
deaths. This disease would not be fatal unless the dolphin’s
immune systems were suppressed, as they were in these cases, by
environmental contaminants," said Dr Verné Dove, report author
and veterinarian with WWF Cambodia. Researchers found toxic
levels of pesticides such as DDT and environmental contaminants
such as PCBs during analysis of the dead dolphin calves. These
pollutants may also pose a health risk to human populations
living along the Mekong that consume the same fish and water as
the dolphins.