Not sure what the article said as I have not read it. But I think it's a common myth that coyotes can't see colors.(like red) I don't think that they see them like we do, but they still see them.

Weedwacker
Indiana Predator Central

Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe.

Frank Zappa