One would always expect to find alien-like creatures in the deep ocean, but who knew something so horrifying looking already exist by the shore? Behold- the Japanese skeleton shrimp! They don’t look like your usual shrimp… with their slender bodies and long appendages, it sure doesn’t look tasty to humans, but fish in New Zealand and Europe loves to feed on them! They got their name off their skeletal appearance, and since they have a very distinct upright posture in the environment, they almost look like stick insects we see on land!

They may look scary, but they only reach a maximum length of 3.5cm for males and 1.5cm for females in Canada! They are commonly found near docks on man-made structures such as ropes, buoys, or artificial reefs in massive quantities due to their fast reproduction, fast maturation, and ability to tolerate a wide range of temperature and water salinity. They may compete with mussels for food and space, which threatens the local population. Males are also extremely aggressive, towards other males as well as to the native skeleton shrimps. So far, few indirect/direct impacts to the environment have been observed.

They are native to Japan and are an introduced species along the west coast of North America. They have been widely introduced to non-native regions all over the world in the last 40 years. Their dispersal is most likely due to human activities, but the exact method of how they got to North America is unknown. Since ports in Japan have important shipping routes to North America, it’s the most likely way those little skeleton shrimps get here. Ports of Japan were also considered important sources for non-native species introduced via ballast water. We have already observed volume and rate of oceanic shipping increasing the global dispersal of non-native marine species. It is highly possible, that with such increase, an increase in the global introductions of the Japanese Skeleton Shrimp can be expected over the next few decades.

They can survive transoceanic transportation in ballistic tanks and sea-chests. And this becomes an important transport vector for this species. They are known to be opportunist feeders and to consume any readily available organic material such as diatoms, dinoflagellates, and even other crustaceans such as other Japanese skeleton shrimp or isopods. In fact- they have been so successful, that they established populations in 36 known locations throughout the world! Surviving without food for extremely long periods of time, wide range of physiological tolerances, very fast maturation- all are factors that increase their survival during transportation and enable them to colonize new habits! Next time when you walk on a dock- peek below the water- you might spot those little shrimps!

For more interesting facts and to see how they move! Check out this link and this video!