Two Black Koi Fish Swimming Near The Surface Of The Water In A Pond - Closeup Shot

black koi fish cyprinus carpio fish aquarium fish aquatic fish pond mature koi species vertebrate koi fish koi omnivores national geographic nat geo slowmo pond closeup swim swimming fins creature japan scales animals japanese habitat environment two water garden water fauna active beautiful common behavior black surface peeking nature natural intellectual marine decorative outdoors ornamental domesticated park view sociable