Sea Hare - Aplysia californica - Photo by Genny Anderson

It has been discovered that ink which is squirted out by sea hares makes them less appetizing to other predators. This discovery was published by  researchers at the Georgia State University.

The study’s focal point was the sea hare’s (in the scientific world known as Aplysia caifornica) defense mechanism. The findings of the study were just recently published in the well respected journal Animal Behavior.

When a sea hare feels threatened, much like an octopus, it will release a purple colored ink and white opaline. This colorful mixture also happens to contain amino acids, feeding deterrents and some other compounds which may make the would be predator think twice on chowing down on the sea hare.

Two researchers, Charles Derby and Matthew Nusnbaum, were examining this extraordinary defense measure in the sea hare, and how it deterred a Bluehead wrasse (known in scientific circles as Thalassoma bifasciatum) as the guinea pig.

They carried out a live feeding assay, in which the hapless Blueheads were offered either a complete sea hare, or one which had had their ink sack removed.

They also monitored the number of times the bluehead attacked the sea hare, if ink was in fact released, and the amount of injury the sea hare took in the process.

They then proceeded to do a bunch more tests, and the final outcome? They ultimately found that the ink has many qualities which predators just don’t like.