Coast KZN

02 Dec 2021

Gill netting among serious Zinkwazi estuary threats

Juan Venter (North Coast Courier) Picture: Environmental company Coast Wise is conducting an investigation into the Zinkwazi estuary in line with government's mission to revitalise estuaries countrywide.

Environmentalists have been tasked to bring the Zinkwazi estuary back to life. This after its slow decline, most notably owing to illegal gill netting operations and unauthorized breaching to protect croplands.

Working in partnership with the Economic Development, Tourism and Environmental Affairs Department to bring the country’s estuaries up to scratch, Coast Wise Consulting has released a report on its findings of the Zinkwazi estuary. Once finalised, the report will be submitted for the establishment of an estuary management plan.

Coast Wise recommended the estuary enjoy partial protection by including a “no-take zone”, meaning no river resources may be removed from the area. It also recommended that 50% of the estuary remain undeveloped.

While its condition may not be as bad as the Tongaat estuary, the report said Zinkwazi needed protection if it was to recover. Moderate levels of pollution, habitat loss and invasive alien plant species have been recorded.

Fishing pressure on the estuary remains high, and also of concern was the infrequent illegal breaching of the estuary to protect low-lying croplands. The threat of gill netting operations, recreational fishing, and bait harvesting was high.

According to the report, eutrophication and chemical contamination are also a concern. It was found that a septic tank frequently floods the estuary’s mouth, contaminating it with raw sewage. As for chemical contamination, Coast Wise said agricultural run-off from cane operations was also a problem.

Eutrophication is a leading cause of the deterioration of freshwater and coastal marine ecosystems in the world. It is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, causing excessive plant growth and threatening river species such as fish.

Plants that cover the surface of the water block out sunlight, reducing water oxygen levels.

Coast Wise will present an estuary management plan this Wednesday (December 1) on the Zinkwazi estuary at 4.30pm. Join here: