Project 4.8.7

Increased understanding of marine stinger risk

Project Leader: Prof Michael Kingsford, JCU

In response to concerns about the impacts of marine stingers (jellyfish) on the Great Barrier Reef tourism industry, this MTSRF-funded project has substantially increased our understanding of temporal and spatial changes in distribution patterns of some of the stinger species known or suspected to be associated with irukandji syndrome. Two hundred and sixty-three cubozoan jellyfish were sampled using light traps (they are attracted to lights at night) during the summer months across different habitats and different locations in the northern half of the Great Barrier Reef. While no cubozoan jellyfish were found offshore at any latitude, capture records indicated that, at least in the case of Carukia barnesi (the chief causative agent of irukandji syndrome), populations were very localized at small spatial scales, such as bays, from the mainland to mid-shelf reefs. In 2007/8 relatively high numbers of many kinds of jellyfish were observed, suggesting that conditions acting at scales of hundreds of kilometers affect jellyfish abundance, including that of cubozoans. The results from this project indicated that the highest risk of envenomation for swimmers occurs on reefs from the mainland to mid-shelf, especially if granitic islands are present. The period of greatest risk is from October to December, especially if rainfall has been low that season.