Two thirds of the earth’s surface is water and in the warm tropics, much of it is virtually lifeless. Void of nutrients essential for the growth of plankton, anything that lives there is either a part of a reef ecosystem or in transit. Yet miraculously, for five months out of the year, nearly 1000 humpback whales migrate to a chain of 177 islands in the south Pacific known as the Kingdom of Tonga. It is where these colossal animals unite to mate and give birth.
A female humpback named Moa started her life here six years ago. She was birthed near the small Tongan island of Vava’u. Tonga is an ideal nursery as it provides sheltered areas with shallow warm water. Moa was born late in the season and didn’t have time to mature in preparation for the 5000 km migration from Tonga to the cold waters of Antarctica. Lacking strength, her mother pushed her along above her head over the course of the dangerous 24-day journey that stretches along the coast of New Zealand and Australia. Orcas and large sharks are the only natural predators to humpbacks.
Moa and other humpback whales spend 5 months of the year building fat reserves near Polar Regions where food is abundant and predatory impact is low. Consuming nearly 2 tons of food every day often means working as a team in a process known as “Bubble Netting”. A group of whales will ascend from as deep as 200 meters slowly releasing air, trapping small fish and krill, until the team surfaces together with their mouths wide open capturing their prey. They consume around 2 tons of krill every day.
June through October mark the cold winter months in the Antarctic. However, Moa and the other humpbacks returned to the Tongan waters early this year. A shift in global weather influenced the krill hatching cycle and by late September, a month earlier than reflected in recorded history, the mass of whales already left. Moa, showing signs of pregnancy, stayed behind. She can’t risk calving during her journey back through unprotected waters leaving her alone and exposed.
A week passed and a new female calf playfully swims around her exhausted mother. Over the next six months, the young humpback will consume nearly 400 liters of pink milk per day. Moa, Having already lost nearly a third of her body weight, is now starving. Yet, having been born late herself, Moa and her juvenile have a fighting chance of making it back to the feeding grounds. Little is known about humpback migrations but there’s a chance that a male escort could accompany them.