Whale Wide World; The migration route of the Southern Humpback whale

Ha’apai Group
South Pacific, part of the Tongan archipelago. Sparsely populated
JUST AS the sun crosses the equator into the southern hemisphere, by mid-September, the Humpback whale bids adieu to the warm South Pacific. Having spent the summer frolicking and mating, it is time to follow the sun to the Southern Ocean, thus kicking off one of the longest animal migrations in the world. Six thousand kilometres to the south, the long rays of the sun are warming the waters around Antarctica, melting the ice and exposing the krill-abundant waters around the continent. For the whale, which weighs up to 40,000 kg, even the quintessential tropical getaway of coconut fronds, emerald-blue waters and the golden sand cannot convince it to stay.

White Island
Bay of Plenty, New Zealand. Privately owned. Open to tourism
The humpback whale leaves behind the tropics within the first week, covering about 200 km per day on average. Having followed the Tonga trench initially, the whale continues southwest following the Kermadec trench, which rises sharply at the eastern edge of New Zealand. Along this arc (just west of the whale’s migratory route) is White Island, in essence the crater of an active volcano, which has been built by continuous volcanic activity over the past 1,50,000 years. Silhouetted in the distance, as seen from the whale’s perspective, the island and its omnipresent volcanic gas lives up to the full Maori name for the island Te Puia o Whakaari, meaning “The Dramatic Volcano”.

Auckland Islands
Sub-Antarctic, New Zealand. No permanent human habitation.
Spiralling low pressures from the west to the east have battered these islands in the middle of the Southern Ocean for millennia, shaping them topographically. Impressive 500 m-high cliffs rise to the west and gently make their way down to mean sea level on the east. Roughly three weeks after leaving Tonga, the whale once again passes a gathering of life here — floating kelp forests, sea lions and seals. On the ridges of the islands, the flora changes with height and act as breeding colonies for albatrosses, penguins, petrels, shearwaters, shags, teals and a range of land birds.

Scott Island
Antarctica. Uninhabited
Just a few hundred metres from the date line, Scott Island stands as a sentry to the Ross Sea. Each winter, this island witnesses Antarctica advance to three times its size, and in summer the island sees the whale arrive, before, eventually, heading further towards the South Pole. In early summer, the ice is still fast around the island and for the arriving whales, these waters are the first pit-stop in four weeks. By this time, the whale has lost up to 3,000 kg of body mass and must make up by feeding abundantly in these waters. Krill, a nail-sized crustacean, but with the total biomass about twice that of humanity, is its prey and the whale feasts on them.

Possession Islands
Ross Sea, Antarctica. Uninhabited
On the 21st of December, the sun is at the Tropic of Capricorn, and there is 24 hours of sunlight at the South Pole. The western edge of the Ross Sea begins to slowly thaw and become ice-free, attracting orcas, albatrosses and whales. Soon, the Possession Islands become completely ice-free — this small cluster of black rocks stands in stark contrast to the whiteness of Antarctica. And in the water, the humpback whale now feeds on krill, in an ecosystem that is in equally sharp contrast to the humidity of the tropics. By May, it becomes too cold to remain at these latitudes and the whale, once again, follows the sun as it heads north, passing the islands in reverse order this time around.