Alien jellyfish hitch a ride on ships Exotic jellyfish from
Japan and Europe are stowing away on ships and thumbing a free
ride to Australia, new research suggests. According to a US and
Australian report in today's Proceedings of the National Academy
of Sciences, moon jellyfish are hitchhiking around the globe in
ships' ballast waters and hulls. And they may have been doing so
for more than 500 years when international shipping and trade
began in earnest. While moon jellyfish are found in many parts
of the world, including Australia, researchers from the
University of California, Davis and the University of New South
Wales have found strong evidence that most are not indigenous to
the area they live in. The finding adds to data from recent
surveys suggesting that around 23% of all marine species in
international harbours are not indigenous, a situation
scientists fear could displace local marine species, threaten
ecosystems and cause billions of dollars in damage and
preventive control. Around 3000 species o