En-en adult card 27 marine biodiversity

Card #27: Marine Biodiversity

Causes		Consequences
Increase in Water Temperature Pteropods and Coccolithophores		Starvation

Pteropods and coccolithophores are at the base of the ocean food chain.
Therefore, if they disappear, all marine biodiversity is threatened. The warming of ocean waters also threatens marine biodiversity.

Explanation

For the moment, marine biodiversity is more endangered by overfishing than by climate change or acidification. But in the long term, these two phenomena will considerably increase their pressure. The FAO estimates that between 660 and 820 million people worldwide, about 10% of the world's population, are directly or indirectly dependent on fisheries and aquaculture.

Correction

Causes

• Increase in Water Temperature
• Pteropods and Coccolithophores

Consequences

• Famines

Other possible links

Other causes

• Human activities With this link, we can signify all the degradations that humankind is inflicting on marine life, such as plastic pollution and overfishing. This is irrelevant to the subject of climate change, but it is interesting to make the link anyway. If we are talking to an older audience, we can for example mention the size of sardine tins which has decreased because they don't have time to grow before they are fished.

• Terrestrial biodiversity The two types of biodiversity can interact with each other.

To go further

Direct impact of human activities

Overfishing is the main cause of the disappearance of fish. Here are some numbers:

• Every year, between 1,000 and 2,700 billion fish are caught. If humans were killed at the same rate, it would take only 37 hours to exterminate the human population.
• Plastic pollution kills 1.5 million marine animals, or 0.0001% of all fishing-related deaths.