The two inch long Harlequin Shrimp is the most uncommon Hawaiian shrimp and by far the most bizarre! They are found in dark underwater caves and almost always are in pairs. When divers find them most of the time they do not even know what they are looking at because these shrimp look more like exotic flowers than an animal.
These colorful fat bodied shrimp have modified front pinchers that look like a large leaf and they hold the pinchers out in front of their body for protection. When you get close to them they wave these large blade like pinchers as if they are doing a karate exercise. It is amazing to watch them perform their karate dance and their pincers not only protect them from predators but are also used to gather food. Their favorite food are sea stars and when they find one they crawl onto the star and chop off one of the legs using their modified pinchers. The sea star usually survives and will grow back a new leg of which the Harlequin Shrimp may dine on at a later date. It sometimes takes the pair of shrimp an entire week or two to consume the sea star leg.
In Hawaii we do not have many sea stars compared to other Pacific Islands so we do not have many of these expotic shrimp and it is a real treat to find a pair of these crazy looking creatures out on the reef. Their bright colors are a warning to predators because the shrimp consumes toxins from the sea star it eats and more than likely the shrimp taste bad. I shot a video of a pair of these shrimp way back in a cave at about 40 feet deep and not one predator fish would bother them but if the fish found a different shrimp species they would gobble it up quickly.
There is no Hawaiian name given to these small shrimp more than likely due to the fact that they live back in underwater caves where no one could see them. I found one pair of Harlequin Shrimp in a cave in Kauai that was feeding on a bright red sea star leg and over the next several months I went back to the cave and the shrimp had not moved more than a foot away from where I originally found them. If these shrimp were as large as a small dog they we be a perfect subject to be in a Star Wars movie as they just do not look like they belong on Earth!
You can see the Harlequin Shrimp in action in my upcoming movie called The World Guide To Hawaiian Reef Creatures. Most of my underwater educational movies are now up on my web page at www.underwater2web.com. The movies are super educational and can be used in the classroom or for teaching the kids about marine science at home.
Terry Lilley is a marine biologist living in Hanalei Kauai and co-founder of Reef Guardians Hawaii, a nonprofit on a mission to provide education and resources to protect the coral reef. To donate to Reef Guardians Hawaii go to www.reefguardianshawaii.org.