GIANTS of the ocean

AMY PEROLD
12 February 2020

Whales are the largest animals on Earth and occur in every ocean. The tongue of a Blue whale can weigh as much as an elephant and its heart as much as a car!

Each year on International Whale Day, 20 February, we celebrate these giants. Join us as we take a glimpse into the lives of these amazing cetaceans that call our stretch of coast their home, at least for some of the year

Although 26 whale species occur in Southern African waters, Bryde’s whales, Humpback whales and Southern Right whales are the three species we find most regularly in Plettenberg Bay.

Bryde’s whales (Balaenoptera brydei) are a resident species in South African coastal waters and can be seen in the bay all year round. They are an elusive species and can be difficult to spot. Common characteristics to look out for include the 3 ridges on their head and their slender dorsal fin curving into a trailing edge. Bryde’s whales can dive more than 300m spending up to 15 minutes beneath the water before returning to the surface to breathe.

Picture 6

credit: Dr. Gwenith Penry

Humpback whales (Megaptera novaeangliae) are easily identifiable by their hump shaped back with a small dorsal fin and long pectoral fins. They are a migratory species that travels from summer feeding grounds in Antarctic waters to winter breeding grounds in sub-tropical waters off Southern Africa. They mainly feed on Antarctic Krill (Euphausia superba) and some schooling fish. In order to stay healthy, adult whales must consume 5-6% of their body weight each day.

Picture 7

Southern right whales (Eubalaena australis) are also a migratory species. They are large stocky whales with heads usually measuring up to one third of their body length. Like Bryde’s and humpbacks, they are baleen whales which means they lack teeth and rather use a comb-like strainer of baleen plates and bristles to engulf zooplankton as they swim. They can occasionally be seen skimming the surface with their mouths open.

All southern right whales have a unique pattern of callosities on their heads. These are white patches of raised and calcified rough skin colonised by cyamids (whale lice) that live on the head and around the jaw of southern right whales. These callosities form unique patterns and are often used by researchers to recognise and identify individuals.

Picture14

Southern right whales have a characteristic wide V-shaped blow reaching up to 5m high! Bryde’s and humpback Whales both have a single blow shape.

Picture 8

Humpback Whale tails have a white underside whereas southern right and Bryde’s are both black. Bryde’s are rarely seen with their tail flukes up.

Picture 9

Nature’s Valley Trust is currently working on an exciting ‘Sustainable Marine Tourism’ project in partnership with Nelson Mandela University and funded by WWF Nedbank Green Trust. The project is the first of its kind in South Africa focusing on the boat-based whale watching industry. Although our current regulations are globally perceived as strong, the efficacy of and compliance with these regulations has not before been measured. The study aims to test these current regulations and ensure they are strong enough and being used correctly in order to protect wildlife effectively. We work by studying animal behaviour both with and without the presence of vessels from both land and sea. Alongside this we are working to quantify the industry to show its impact to the economy, how this feeds into the local community, and how important it is to ensure it is functioning at a safe carrying capacity to sustain the industry. Additionally, we aim to engage with local and international tourists to  understand their perception and expectations of the industry, and whether they are happy with the experiences on offer. It is hoped that the unique research done here in Plett can then be used nationally to aid management and inform best practice for wildlife viewing and lead the way, globally, for sustainable boat-based whale watching. 

We strive to #sharetheseas, where the needs of the industry, community and wildlife are all catered for.

Picture 10

Post your comment

Comments

No one has commented on this page yet.

RSS feed for comments on this page | RSS feed for all comments