Auk
Some auks are small birds and some are medium-sized birds.  All auks live on or near the ocean.  They have long, thick bodies.  They have small wings and tails.  They have short legs and webbed feet.  Auks do not walk well.  They flap their wings very fast to fly.  When they fly, they cannot change direction as fast as other birds can.  But auks swim and dive well.  Auks look like penguins because they are usually black and white in color, with black on the back and white on the belly.  But auks and penguins are not closely related.  They do not live in the same places.  Auks can fly and penguins cannot.