Fishy fishes?

“Is ‘fishes’ a word?” asked one student.  Hmmm, I thought.  Let’s check.  It seemed right when I made the sign for these creative fish with true to life adaptations- but then again, fish is the plural of fish, isn’t it?  So we checked.  Lo and behold… Fish is the correct plural for more than one fish UNLESS there are more than one species of fish in which case fishes is correct.  Aha!  And since there are many species of fish swimming on this bulletin board (every class has taken a peek) they are indeed fishes.