Sea Slugs

Sea Slugs Invade Auckland Coast
Discovery Earth Alert, May 18, 2000

Large sea slugs are infesting beaches along New Zealand's North Shore, giving scientists reason to believe that bacteria in the water is attracting the creatures. The slugs, also known as sea hares, look like balls of brown jelly and grow to the size of a fist. The slugs crawl on the seabed and live off a cyanobacterial algae caused by sewage. When they are squashed, they squirt out a purple-colored fluid. Witnesses have reported that the stench in the infested area is so horrendous that even seagulls will not go near the slugs.

Professor John Buckeridge of the Auckland University of Technology reported that the slugs' population is becomingly increasingly larger as they gather near Long Bay and Red Beach. He warned that local officials needed to scrutinize the impact of new high-density housing and its subsequent generation of sewage in the region. Alwyn Rees of Auckland University related the warm weather patterns caused by La Nina to the growth of the cyanobacteria, which in turn had produced large numbers of slugs. "What happens is we get very, very low biodiversity but large numbers of a few species. When that happens that's what I'd call an indication that something's not quite right," said Hugh Leersnyder, the Auckland Regional Council's coastal resources manager.