Scare over killer algae

Scare over killer algae

By Amy Phillips

SYDNEY — Signs were posted around Berowra Waters on January 22 warning against swimming in the water after 50 dead fish were collected from Berowra Creek.

This was the fifth algal bloom this summer affecting the Berowra Waters area of the lower Hawkesbury-Nepean system.

According to marine biologist and Streamwatch spokesperson Roger Campbell, an oversupply of nutrients caused the latest bloom, resulting in oxygen deprivation killing fish and shore life. It is likely that the activities of the sewage treatment plant and industry in the area are to blame.

Toxic blue green algae blooms affect over 10% of the Hawkesbury-Nepean system. Dr David Hughes, spokesperson for the Coalition of Hawkesbury and Nepean Groups for the Environment, said algal toxins were known to act like nerve gas and cause dermatitis, skin and eye irritation or intestinal irritation if swallowed.

From GLW issue 130