Why is it important to monitor ballast water on tankers?

Monitoring ballast water on tankers is crucial primarily to prevent the spread of invasive species. Ballast water is taken on board to provide stability and balance to vessels during transit, but it often contains a diverse array of marine organisms. When ships discharge this ballast water in different locations, they can unintentionally introduce these organisms into new ecosystems, leading to ecological imbalances.

Invasive species can disrupt local habitats, outcompete native species for resources, and significantly alter the biological diversity of an area. This can result in economic harm, as these species may affect fisheries, tourism, and even local industries that rely on the native marine ecosystem. By monitoring and managing ballast water, tankers can help mitigate these risks and protect marine environments.

While monitoring ballast water may have ancillary benefits, such as improved maneuverability or slight enhancements to fuel efficiency, these are not the primary reasons for monitoring it. The most pressing concern revolves around environmental protection and biosecurity, underscoring the importance of option B.