Squids and octopuses produce black or bluish-black ink, while some cephalopods produce brown or red ink. But not all cephalopods can produce this ink.

Is octopus ink their blood?

6) Octopus ink doesn't just hide the animal.

But when sprayed in a predator's eyes, tyrosinase causes a blinding irritation. ... 7) Octopuses have blue blood. To survive in the deep ocean, octopuses evolved a copper rather than iron-based blood called hemocyanin, which turns its blood blue.

How do octopus make their ink?

The ink sac feeds into the rectum, controlled by a sphincter and in some inking events mucus from another organ, the funnel organ is ejected with water and ink through the anus and the siphon to create a cloud of ink.