OVERFISHING - A PART OF THE NEGATIVE PATTERN
Overfishing harms our climate on many levels, both through its harmful effects on the ocean’s capacity to regulate the climate as well as through its direct emission of greenhouse gases. These days, there is a lot of focus on microplastics, but overfishing is in fact considered the main environmental threat to our oceans. It's important to remember that fishing vessels are run on heavy fuels which, besides carbon dioxide, also emit black carbon, sulfur dioxide and nitric oxides. In the Arctic, fishing vessels are the largest cause of greenhouse gas emissions.
Fish oil, commonly used for omega-3 supplements, is the most valuable product of so-called “reduction fisheries” (where the catch is processed to bulk feed, rather than as food for humans). Omega-3s are essential to our health, but our demand for them is contributing both to overfishing and to climate change. Ironically, the actual source of these omega-3s in nature are not fish, but algae – the tiny, little microalgae that convert carbon dioxide to oxygen (and omega-3s) by photosynthesis, just like land-based plants. These microalgae – also called phytoplankton – are the main consumers of carbon dioxide in the ocean, and thus play one of the most important roles on our planet in terms of regulating our climate.