HUMPBACK WHALES – AARON BANKS – MARINE MAMMAL BIOLOGIST

Between the months of July and October Humpback Whales occur throughout the coastal waters of the Inhambane region, Mozambique. Each year Humpback Whales migrate between their summer feeding grounds off Antarctica and their winter breeding grounds of the Southwest Indian Ocean.

Being the most aerially active of all whale species and with the breeding season being the best time to experience this behavior, Humpbacks can frequently be seen breaching (jumping) and lob-tailing (slapping tail on the surface). The reason for this behavior is likely to be for a number of reasons, but is generally believed to be associated with communication – a display of dominance or hierarchy; reinforcement of another communicative signal or location. Whatever the reason may be, with humpbacks measuring up to 16 meters long and weighing up to 45 tons in weight, a breaching humpback is certainly one of the most impressive behaviors to witness within the animal kingdom.

Their tall bushy blows often scatter the horizon as males compete against each other for females and mothers-to-be give birth to a single calf. The newly born calf (4.5m long) will suckle its mother’s milk for the next 6-12 months. The fat-rich milk will provide the calf with not only enough energy to grow but also the energy to sustain the long journey to the feeding grounds in the cold waters of the Southern Ocean.

Below the surface, males produce an incredible audio display or “song”. The song, which can be over 30 minutes in length, (depending on the population) is repeated over and over again with precision. The reason behind this “song” is still in debate; however, each male within the population sings the same song, which slowly evolves over time. The song can be heard throughout the breeding season and is easily heard by scuba divers or snorkelers, adding a haunting but yet beautiful addition to the dive. On a calm day, you may even hear it reverberating through the hull of a boat.

Whether you observe them from land or by boat, the recovering population of Humpback Whales along the shores of Mozambique provides an opportunity to witness one of nature’s most graceful animals.