It’s whale season around New Zealand and Australia, and this year they are with many. Watching them breach, swim, and flirt with the water, boats, and one another, is an absolute spectacle, but the return of the whale means more than fun.

Read the long-read article on this topic in Dutch.

Whales are mighty creatures playing a crucial yet underestimated role in the overall wellbeing of our oceans, and therefore of our wellbeing. The contribution of these heavy-weight creatures lays in their role as a gardener of phytoplankton.

This kind of algae might be unknown but should not be unloved. It produces 50% to 80% of the earth’s oxygen, and absorbs 40% of the human-produced CO2! This is the equivalent of 1.7 trillion mature trees or four times the Amazon rainforest.

While phytoplankton keeps us alive, whales keep phytoplankton alive. Whales love to eat krill which loves to eat phytoplankton, so by eating krill they prevent phytoplankton from being overeaten. During feeding season, an adult blue whale eats about 3 tons of krill per day. All that food results in a lot of whale poo, which is even more fortunate for phytoplankton, because it seems to be its perfect fertilizer.

The task of the whale as a gardener goes beyond phytoplankton. They spread nutrients, sediments, and oxygen through the ocean between the bottom and the surface, and hundreds of kilometres between the tropics and Antarctica in the Southern hemisphere, and the Arctic in the Northern hemisphere. This helps the marine ecosystem thrive.

The miracles of the whale go further. By the end of their lifetime, the whale carcass sinks to the bottom of the ocean where it serves as a huge carbon sink; a whale body can store up to 33 tons of CO2. So, whales fight climate change even after their death. Bless them!

This year, while we all had to stay home during COVID-19, and trade and tourism where down, whales went up. About 35,000 humpbacks are expected to migrate along Australian’s East Coast. An incredible increase knowing that there were only about 300 left by the end of the 1960s. Luckily, the Australian government has banned whaling in place since then, resulting in an increase of 10 to 11% per year.

Knowing their crucial role for our oceans to thrive and survive, we can only cheer them thriving and surviving along our coasts. Cheers!