if river otters spend most of their time in the water how come they con only hold their breath for 4mins?

Answer 1

River Otters spend most of their time on the water surface, where they don't need to hold their breath. Also, look at the river otter's size. Their lung capacity does not appear to be huge due to its body size (larger bodies usually carry larger organs such as the lung). Most of the rivers that these otters inhabit are also quite shallow, so they only spend a very short amount of time underwater when they need to submerge themselves.

Answer 2

How long do you need to stay under in a river? They don't make deep dives.

Answer 3

They swim at and float on the surface most of the time.

Answer 4

Because they keep their head out of water the rest of the time....