Summary
Highlights
Despite alarming global trends, some countries, like Chile, continue to disregard the consequences of kelp destruction. Chile is the world's leading wild harvester of kelp, accounting for nearly 40% of global wild kelp harvesting. This is particularly concerning as Chile holds one-third of the world's Macrocystis ecosystems. While other nations are expanding seaweed farming, Chile largely relies on exploiting natural marine wild forests, with only 5% of its total seaweed production coming from aquaculture, compared to China's 0.1% aquaculture production.
While the destruction of terrestrial forests due to fires, storms, and deforestation draws global attention and resources, equally valuable wild ecosystems in the ocean are being decimated with little public awareness or action. Species are going extinct, biodiversity is shrinking, and coastal communities are suffering from coral loss, bleaching, and the disappearance of vital marine habitats.
Kelp forests are essential to ocean life and the planet, recognized by scientists as some of the most productive ecosystems on Earth. Like rainforest trees, kelp acts as a barrier against tsunamis and storms, prevents erosion, and plays a key role in coastal protection. A single square meter of kelp can house up to 100,000 organisms across 200-300 different species. Kelp also absorbs CO2 at rates 10 to 50 times greater than land forests, making it a powerful climate solution and a significant carbon sink.
Kelp could become the most sustainable and eco-friendly food source globally, with a single hectare of seaweed farm producing more protein than the same land area used for cattle. It doesn't use freshwater and is highly nutritious. Seaweed is also used in many daily products, particularly in processed forms in Western countries. Its extracts, like algin, are used as stabilizers and emulsifiers in foods like ice cream and yogurt. Kelp is also a superfood with antioxidant and anti-inflammatory properties, and its extracts are used in skincare and wound healing, allowing for the growth of human skin tissue.
Scientific research continues to expand the use of seaweed into cosmetics, pharmaceuticals, textiles, and agri-food. A recent study confirmed that supplementing cattle feed with red seaweed can reduce methane emissions by over 90%, offering a significant solution for livestock emissions. The demand for kelp has sharply increased over the last two decades.
Kelp forests are highly vulnerable to environmental factors and human-related stresses. Terrestrial deforestation and agricultural runoff introduce excess nutrients and turbid waters into the ocean, destroying marine forests that require light. Rising CO2 levels lead to ocean acidification, further compounding the damage alongside warming temperatures, heatwaves, and pollution. California has lost over 94% of its kelp, Tasmania up to 95%, Norway 80%, and Canada 67%, with similar declines in other regions including Britain and Portugal.
The high prices for kelp have led to a 'gold rush' in Chile, where fishermen are cutting one and a half tons of wet kelp for significant earnings. The most damaging extraction technique involves taking the entire root, destroying surrounding marine life. This practice, often unregulated and with premature quota assignments, leads to the loss of unique genetic lineages that cannot be recovered. When kelp forests are removed, herbivores like sea urchins can prevent regrowth, creating 'urchin barrens' as seen in California.
Unlike terrestrial reforestation, kelp reforestation is still in its research phase. Successful small-to-medium scale experiments involve transplanting reproductive adult seaweeds to restoration sites, allowing them to reproduce naturally. Innovative approaches like using wave and solar energy to restore natural upwelling and irrigate offshore kelps have shown promising results, increasing growth rates fourfold. However, large-scale global restoration remains a long-term goal, underscoring the importance of stopping wild logging until effective and economically viable replanting methods are widely available.
Kelps are ecosystem engineers, creating and modifying habitats by changing the chemical and physical composition of their environments. Over 150 marine species live directly under Chilean kelps, which provide food and shelter. Kelp forests serve as natural nurseries for many fish species and invertebrates, including krill and mollusks. Hundreds of species are indirectly dependent on these forests. Even endangered animals like the sea otter and the blue whale rely on kelp forests for their food sources.
Globally, 220 species of seaweed have commercial value, cultivated in about 50 countries. Seaweed cultivation is proving to be more environmentally friendly than fish farming, growing naturally without feed, pesticides, medicine, or fertilizers, making it the fastest-growing aquaculture industry. The FAO projects that the global market value of seaweed will more than double by 2024. Sustainable seaweed farming offers coastal communities an opportunity to improve their standard of living, requiring training, technical support, and funding to shift away from destructive wild-harvesting practices.