Human noise underwater is killing whales, dolphins.

Before you ignore this, let me remind you that fewer dolphins means fewer cans of tuna.

Levels of noise in the world's oceans are causing serious problems for whales, dolphins and other marine mammals, a report warns.

The International Fund for Animal Welfare (Ifaw) says undersea noise blocks animals' communication and disrupts feeding.

Naval sonar has been implicated in the mass deaths of some cetaceans.

In some regions, the level of ocean noise is doubling each decade, and Ifaw says protective measures are failing.

"Humanity is literally drowning out marine mammals," said Robbie Marsland, UK director of Ifaw.