Phyllorhiza punctata
(‘spotted jellyfish’)           

Researchers at the Dauphin Island Sea Lab are very interested in reports of this species. Large numbers of Phyllorhiza punctata were reported in the summer of 2000. At that time, it was believed that this species had never been in the northern Gulf of Mexico before. Since then, though, we believe smaller populations have been seen by fishers and shrimpers in the coastal waters of southern Louisiana for as many as 10 years.

Why so much interest in this species? This species is particularly interesting because it is an ‘invasive species’. That means it is not native to the region. In fact Phyllorhiza punctata is from a family of jellyfish that is not even native to the Atlantic basin. Current theory states that the jellyfish were introduced about

    
50 years ago through the Panama Canal. They were probably transported as the polyp stage on the hull of a ship. Populations of Phyllorhiza punctata have been established along the coast of southern Brazil and in the Caribbean Sea in Puerto Rico. At present, we are seeing populations becoming established along the northern Gulf of Mexico from northeastern Texas to Mobile Bay. Another population appears to be established in the Indian River Lagoon on the east coast of Florida.
 


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 Why should we be concerned about this species? Like many other non-native species, Phyllorhiza has the potential to create ecological problems. The large bloom of jellyfish in 2000 was an important glimpse into the potential impact that these jellyfish could have. Like other jellyfish in the Gulf, Phyllorhiza consumes large amounts of small zooplankton (including fish eggs and larvae). In addition, Phyllorhiza directly impacted the shrimp industry because nets were becoming clogged with jellyfish.

Can anything be done about these jellyfish? First of all, we know very little about jellyfish as natural members of coastal ecosystems. It is difficult to develop a strategy eliminating a species when very basic information about its

biology is lacking.And second, Phyllorhiza creates problems when it is in the planktonic ‘medusa’ stage. However, the very small polyp stage can survive for years. It is this stage that would need to be targeted for developing a removal strategy. However, we know less about polyp stages than we do about the medusa stage. So, it is probably years before we can begin developing a strategy to remove these jellyfish from the affected regions. In the meantime, we are conducting a number of important research projects in order to learn more about how this jellyfish invades new regions as well as what the ecological problems may result from current and future invasions.
 
What can people do now? The most important response is to provide scientists with information when Phyllorhiza is observed. This DockWatch web site is just one way to let us know when and where you saw a jellyfish (not just Phyllorhiza, but all jellyfish). People can also call us at the Dauphin Island Sea Lab using a direct line to a recorded message (251-861-2289).  Also, Dauphin Island Sea Lab scientists need tissue samples of Phyllorhiza.  Since the jellyfish does not have a painful sting, it is easy to collect the jellyfish into a large zip lockbaggie and freeze it until it can be picked up by one of our scientists. If the whole animal cannot fit into a baggie, then taking a slice of the animal will suffice. Be sure to freeze it right away and call or submit your information using the web site.  


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