BWB – Such a sh!t

Whales, dolphins and seals play a central role in the marine ecosystem. They make a decisive contribution to the stability and health of the oceans. The so-called ‘whale faeces pump’ effect shows their most fascinating function in supporting the nutrient cycle.

Their faeces are extremely rich in nutrients, especially nitrogen and iron, which are often scarce in the upper water layer. These nutrients promote the growth of phytoplankton – tiny algae that form the basis of the marine food chain. Phytoplankton also play a crucial role in capturing carbon dioxide from the atmosphere and produce much of the oxygen we breathe. 70% of the oxygen produced on our planet is produced by phytoplankton. By bringing nutrients from the depths to the surface, whales support the productivity of the oceans and indirectly contribute to global climate regulation. This function is so important that scientists often refer to whales as ‘ecosystem engineers’.

In addition, marine mammals influence the populations of their prey through their feeding habits and thus prevent overpopulation of individual species, which could jeopardise the ecological balance. Orcas, for example, regulate seal populations through their feeding habits, which in turn influences fish stocks.

Even after their death, whales play a crucial role. As soon as their massive body – the so-called ‘whale carcass’ – sinks to the seabed, it serves as the basis of life for a multitude of organisms. Up to 200 species benefit from this ‘underwater buffet’, which provides energy to the deep sea for years. In times when marine ecosystems are under threat, the importance of marine mammals is becoming increasingly clear. Their protection is therefore not only a question of species conservation, but also essential for the health of our planet. Our survival depends on it. What would happen if the oxygen tap was turned off for us?

By Fatima Kutzschbach