If they're wild mice then they find their ways to drink some. From puddles and such.
If they're pet mice, then you might want to give them a hamster bottle. You could also give them a small bowl of water, with a small amount of water in it depending on the size of the mouse. This is more difficult then giving them a bottle because if the bowl is too low on the sides they step into the water, which could get them cold and sick. If the bowl is too high on the sides then they can't get any water. Other ways could be using an eyedropper, and squirting water into their mouth, but not too much or you could drown them.
If you still can't give it water then give it lettuce, watermelon, or tomatoes. Something with liquid, and that should be enough for them.
Yes, Mice need water.
Mice don't like water because they can drown.
Water.
streams
Take a spray bottle and squirt the mouse or mice with fresh water
Swimming for its life - water is not a natural environment for mice.
Pet mice can consume about 1 teaspoon (5 ml) of water per day. Wild mice often get by on much less than that.
sugar and water?
rice water
The mice hit Dogzilla with a blast of warm, sudsy water.
Mice live on land, fish live in water. On in not the normal prey of the other.
I don't think they have to be afraid of mice as they never have confronted them, ever. Whales live in water while mice live on dry land, out of water. I don't think that whales are even aware of whether such a thing (mice) actually even exists. My answer would be no.