On our first dive with these amazing creatures our group watched the female place eggs in the reef. When we returned the male cuttlefish was making this tentacle display to discourage another male in the area from making advances.
Cuttlefish change color and texture for camouflage. I've seen them with inch high rough looking bumps on their backs when hiding near hard corals. These particular cuttlefish were about 18 to 20 inches long.
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