Threespot Damselfish chases away large day octopus by biting its head, octopus moves to another coral block

cephalopoda octopodidae octopus trimaculatus reef scuba tentacle dascyllus seabed damselfish bottom cyanea coral underwater camouflage threespot bite damsel dive abyss diurnal attack day territory protect prey hunter arms color water eight colour changeble intelligent change offspring sub behavior behaviour clever