Watch out! Another series of jellyfish images coming up! Four months ago, we found ourselves floating face down in the cool waters of Wilsons Promontory, gazing through our goggles at something totally magical: the Chrysaora wurlerra, a reddish jellyfish. A few were drifting around our boat, and we were fascinated by their beautiful shape, graceful flow and colour. Some had long trailing tentacles, others did not.
Captivating red jellies
Truth be known, anything enthralls me underwater, it is such a different, enchanting world! Every time we anchor at the Prom now, we look for our little friends. “Friends?” I hear you ask. Some of you might be thinking “foolish girl… dangerous foes, more like!” But this little jellyfish (about 5cms across the bell) is particularly captivating because we had never seen it before and it is a magnificent, intriguing creature. I had to do some research!
It turns out it is not common. It was first recorded in 2008 and has mainly been seen along the New South Wales coast, but our sightings at the Prom seemed to be the first recorded in Victorian waters. May be the fact we are seeing them further south is another sign of global warming. Certainly scientists think that we might be seeing more jellyfish blooms than before because ocean conditions are changing. A combination of over-fishing, climate change, introduction of foreign species, more carbon dioxide in the water and more run-off of nutrients could be the root cause of this increase in jellies. There are reports of jellyfish infestation in many parts of the world.
But at the Prom, we could not describe it as an infestation – just a dozen or so specimens. When you look at them moving about, the Chrysaora wurlerra jellies have a saucer-shaped umbrella which contracts and propels them through the water. They mainly drift with tide and current, but can change direction and depth unhurriedly, fluidly; the tentacles which hang from the umbrella trail gracefully then bunch up and curl as they move through the water. When several of them are around, it is like watching an underwater ballet. It is really mesmerising.
Fire in the waterBut of course the long threadlike tentacles (up to about 30 cm long) are not just for show. They are covered with stinging organs (nematocysts) which are used to capture prey. Surrounding the mouth inside the centre of the umbrella, there are ribbon-like arms which transport prey to the mouth. The Chrysaora is popularly known as the sea nettle because its sting can be very painful. Having got very close to them, although I did not realise at the time, I did get stung by one on the arm and came up with a ribbon of welts a day later… a delayed reaction. It was a bit swollen and achy, and I still had the marks weeks later but it was so worth the trouble! Next time I will wear a wetsuit though, against the cold as well as the stings!
What is in a name?There are different types of jellyfish in the genus Chrysaora. The origin of the name lies in Greek mythology with Chrysaor, brother of Pegasus and son of Poseidon and Medusa. Translated, Chrysaor means “he who has a golden armament.” Lisa Gershwin, the marine biologist who first recorded the particular one we observed, gave it the species name wurlerra. A bit more research on the etymology of wurlerra revealed an aboriginal origin! Wur = fire and lerra = river, “fire water”, a clear reference to the stinging capacity of the species.
Links to interesting sites
We have now started to record our sightings and are even more curious when observing what is under our hulls and photographing what we see down there. Once you start looking, you do find amazing creatures. Here are three sites we find useful:
- The Atlas of Living Australia (www.ala.org.au), a free online resource which provides access to a wealth of information about Australia’s biodiversity.
- Red Map (www.redmap.org.au), an organisation interested in sightings of marine species that are uncommon in Australia or along particular parts of our coast.
- Jellyfish Watch (www.jellywatch.org), a worldwide organisation recording sightings specifically of jellyfish and other marine organisms. These guys are particularly helpful with identification.
These organisations are about public participation and engagement in citizen science projects. It is a great way to explore, share observations and learn.
Enjoy the Gallery!
And now, here is a collection of images of these fascinating creatures, different to the ones you will have seen in a prior post or in the “Just Add Water” article recently published. We hope you enjoy them – at a safe distance! All images were taken with the Olympus TG4 camera.