Video by @bertiegregory. Giants otters are a great indicator species- one that shows the health of the ecosystems. Why? Because each adult otter needs to eat about 4kg/8lbs of fish every day. These otters live in family groups of up to 20 individuals so collectively require a huge amount of fish to support them. As a result, the presence of giant otters on a lake or river indicates a very productive lake. I filmed this family fishing in the Northern Pantanal, Brazil, on assignment for @stevewinterphoto, @natgeo and @natgeowild. Follow Steve and I (@bertiegregory) for news on our jaguar film coming soon!