What an Ocean Dead Zone Really Is

Added: 2026-06-03

[00:00:00]Imagine a part of the ocean where almost nothing can survive.

[00:00:04]Scientists call it a dead zone.

[00:00:06]Here's how it forms.

[00:00:09]On farms, we use a lot of fertilizer.

[00:00:12]When it rains, that fertilizer washes into rivers and then out to sea.

[00:00:17]There, it feeds microscopic algae and they grow incredibly fast.

[00:00:22]But then the algae die and they sink.

[00:00:25]As they rot, they use up the oxygen in the water.

[00:00:28]And without oxygen, fish and sea creatures simply can't breathe.

[00:00:33]So they flee or they die, leaving the water silent and empty.

[00:00:37]The good news?

[00:00:39]When we use less fertilizer, the ocean can slowly recover.