What are significant human practices threatening marine biodiversity?

The response that highlights overfishing and oil spills accurately identifies two major threats to marine biodiversity. Overfishing depletes fish populations, disrupts food chains, and can lead to the collapse of entire fish stocks, thereby harming ecosystems that rely on a balanced population of various marine species. It not only impacts targeted fish species but also affects bycatch, which includes other marine animals unintentionally caught, further straining marine biodiversity.

Oil spills, on the other hand, release harmful hydrocarbons into the marine environment, affecting water quality and harming marine organisms. They can lead to acute damage to marine habitats, such as coral reefs and mangroves, and long-term consequences that can alter ecosystems for years. The toxicity of oil can cause high mortality rates in marine life, impair reproductive systems, and lead to long-term declines in populations.

In comparison, controlled fishing practices and recycling of plastics are typically associated with conservation efforts and sustainability. Cultivation of marine algae is considered beneficial and a potential solution to issues like overfishing and pollution. Therefore, overfishing and oil spills clearly represent significant, harmful human activities that actively threaten marine biodiversity.