In February, we celebrate whales

On February 19, we celebrated World Whale Day, an opportunity to remind everyone how important it is to protect these ocean giants and, more broadly, all marine mammals.

Why whales are essential to our planet’s balance

February 19 marks World Whale Day, an opportunity to celebrate these ocean giants and to remember the fundamental role they play in how our planet works. Long hunted for their oil, their blubber or their baleen, whales have now become a symbol of ocean conservation. Yet their importance goes far beyond their status as iconic species. By influencing marine ecosystems, the carbon cycle and even oxygen production, they play an active part in maintaining the Earth’s great balances. Protecting whales, then, also means protecting the climate, biodiversity and the oceans on which so much of life on our planet depends.

Whales, the gardeners of the oceans

At first glance, a whale seems simply to roam the oceans in search of food. In reality, each of its movements contributes to an essential ecological process. Most great whales feed at depth, sometimes several hundred meters below the surface. There they catch krill, fish or squid before rising to breathe and rest at the surface. On these constant round trips, they bring nutrients up from the depths with them. By releasing their feces near the surface, they enrich the upper layers of the ocean with nitrogen, phosphorus and iron. This phenomenon is known as the “whale pump”. Far from being a mere biological detail, this natural recycling acts as a true marine fertilizer. It stimulates the growth of phytoplankton, the invisible microorganisms that form the base of the entire ocean food chain.

Phytoplankton: an indispensable ally against climate change

Phytoplankton is often described as the “invisible forest of the oceans.” Through photosynthesis, it produces nearly half of the oxygen in our atmosphere. In other words, one in every two breaths we take is made possible by these microscopic organisms. Phytoplankton also plays a major role in regulating the climate. By absorbing carbon dioxide (CO₂), it helps limit the buildup of greenhouse gases in the atmosphere. The oceans absorb nearly a quarter of global human-made CO₂ emissions, and a large share of that capacity depends on phytoplankton. By promoting its growth, whales indirectly contribute to oxygen production and carbon storage on a planetary scale.

True carbon sinks

Whales also play a direct role in the fight against climate change. Throughout their lives, they accumulate carbon in their muscles, bones and tissues. A great whale can store more than 30 metric tons of carbon dioxide, far more than most trees. When the animal dies of natural causes, its immense body slowly sinks to the seafloor. The carbon it contains is then locked away in the depths for several centuries, or even longer. Scientists call this a “whale fall”. Each whale that reaches the deep seafloor then becomes much more than just a carcass.

A dead whale becomes a haven for life

More than 1,000 meters down, food is scarce. The arrival of a whale is therefore an exceptional event. Its remains feed an incredible variety of organisms, one after another: sleeper sharks, deep-sea fish, crabs, amphipods, marine worms, sea stars, specialized bacteria… Some species even live exclusively on whale carcasses. For several decades, a single whale fall can support hundreds of different species and create a true oasis of biodiversity in the heart of the abyss. These fascinating ecosystems are among the most astonishing on the planet, and they show how whales continue to play an essential ecological role, even after death.

Populations that are still fragile

Although commercial whaling has declined sharply since the international moratorium of 1986, many species remain vulnerable. Today, whales face multiple threats: collisions with ships, entanglement in fishing gear, chemical and plastic pollution, underwater noise, dwindling prey and the effects of climate change. Some populations are showing encouraging signs of recovery, while others remain endangered. Protecting them therefore remains a major challenge for ocean conservation.

Protecting whales means protecting the future of the oceans

Whales remind us that no species lives in isolation. Their mere presence influences the flow of nutrients, supports the growth of phytoplankton, promotes carbon storage and sustains biodiversity all the way down to the abyssal depths. By protecting these giants of the sea, we help preserve one of our planet’s most precious natural allies in the face of today’s environmental challenges. World Whale Day is therefore much more than a celebration. It is an invitation to better understand these extraordinary animals and to recognize that their future is closely tied to our own. Because protecting whales also means protecting the oceans… and, ultimately, our own future.