Noise pollution

Aquatic plants have a sense of hearing, which they depend on for simple orientation. Loud noises generated by human activity can damage their hearing and perhaps kill them.

Loud sounds can also kill zooplankton and fish embryos.

Since any additional fossil fuel reserves are useless (to extract all the reserves we already know about would be suicidal), and since mining the sea floor causes other dangers, Prohibiting seismic surveys in bodies of water seems indicated as a first step. Other not-quite-so-loud sounds may also require action.