Coast KZN

03 Jul 2018

Humpback whale survey begins at Cape Vidal

Duncan Guy (Independent on Saturday) Picture: Humpback whales passing the KZN coast and which breach will be counted.

After nearly 20 years, whales passing the KwaZulu-Natal coast have the opportunity to breach and be counted as the first East Coast Humpback Survey begins at Cape Vidal in the iSimangaliso Wetland Park.

A collaborative effort between several organisations, include
ing conservation authorities, conservation NGOs and universities, it will track the population increase of humpback whales as they recover from commercial whaling pressure.

Commercial whaling practised off the northern KwaZulu-Natal coastline between 1908 and 1979, decimated populations of whales in these waters. The protection of humpback whales in 1963 marks one of the great South African marine conservation success stories with numbers steadily increasing over this time.

“The recovery of southern hemisphere humpback whales from severe whaling pressures last century, when some 210 000 animals were slaughtered, must rate as one of the world’s great conservation recoveries,” said Ken Findlay, a professor at the Cape Peninsula University of Technology.

“Populations that migrate on the KZN coast each year were killed in the Antarctic, on their migration and in their Mozambican breeding grounds. Their current recovery at some 10% a year is really heartening to see,” he said.

The monitoring project has been spearheaded by Wild Oceans, a new marine and coastal conservation programme of the Wildtrust, developed in response to the need to ensure ocean health and sustainability for all.

“Over the past decade, it has been presumed the humpback whale population is increasing as the number of reported mortalities have decreased.

“However, threats to these whale populations are accelerating,” said Jennifer Olbers, Ezemvelo KZN Wildlife Marine ecologist.

“Whales communicate using low-frequency acoustic signals which allow interaction over large distances.

“Noise in the ocean, including from large ships or offshore mining activities, can overlap with these acoustic signals used by humpback whales, and have been reported to induce habitat displacement, behavioural changes and alterations in their acoustic signals.

“The iSimangaliso coastline offers an important area in which ocean noise from anthropogenic sources is reduced because shipping lanes are further from the coastline and offshore mining is prohibited, making it an ideal location for such a monitoring survey,” she said.