Exciting news – another pink meanie jellyfish has been discovered and is on display at the Two Oceans Aquarium. Although this jellyfish has yet to be formally described and given a scientific name, this second find by the Two Oceans Aquarium Collections Team suggests that this elusive jelly may be a much more crucial part of our offshore ecosystem than previously imagined.
“This is truly a once-in-a-lifetime opportunity which might very well never be repeated!” – oops, guess we were wrong about the first one!
As with the first pink meanie, which was discovered accidentally at the Aquarium in 2017, this newcomer was also an accidental find. Approximately one month ago, the Collections Team and our volunteer commercial divers were collecting nightlight jellyfish in the waters around Robben Island and in Cape Town Harbour. These night light jellyfish had been washing up in unusually large numbers all around the Western Cape in the previous few months, so we thought this would be an excellent opportunity to collect a few for display at the Aquarium.
Little did the collections team know that their smack of nightlight jellies had a tiny stowaway…
A tiny pink meanie ephyra (the free-swimming baby form of a jellyfish) was hidden amongst the oral arms of the nightlight jellies and over a few short days, as it grew to metaephyra (basically a jelly teenager) stage it consumed all the nightlight jellies that our team had collected!
Needless to say, our resident jelly expert Krish Lewis was thrilled by the rediscovery of this elusive jelly that he had previously dubbed “the unicorn of jellyfish”, and the discovery of one so young gave us the opportunity to study some of the early life stages of this unusual animal.
The pink meanie is now officially on display at the Two Oceans Aquarium in the Jelly Gallery near our I&J Ocean Exhibit.
Pink meanies are voracious eaters, and if our local species is anything like the other types of pink meanies seen in different parts of the world, this small jelly could easily grow to many metres across!
What do we know about pink meanies?
Pink meanies are jellyvorous, meaning they feed on other jelly species by reeling them in with their long tentacles. It is considered the most efficient jellyvorous jelly, as it can digest its prey within two to three hours. Its Mexican cousins have been seen consuming up to 34 other jellies at once.
We also know that those pink meanies are relatively indiscriminate in the species of jellyfish that they feed on, relying on large blooms of prey species rather than the specific species itself. This pink meanie was taking advantage of the large number of nightlight jellies in Table Bay, while our 2017 discovery was found amongst a bloom of compass jellies.
We know from experimentation at the Two Oceans Aquarium that pink meanies do not eat other jelly-like animals. In test feeds, both salps and comb jellies have been rejected as food by the pink meanie. We have found that it only feeds on Scyphozoa (true jellyfish, like compass jellies) and Cubozoa (box jellies).
Cape Town local and avid freediver Lisa Beasley also discovered a pink meanie in False Bay – meaning that this animal may not be as rare as one thought.
Its almost impossible to think of something so pretty and so pink as The Pink Meanie. This rare jelly is jellyvorous - meaning it eats other true jellies by pulling them in with its long tentacles - hence its name. I spent most of the dive with this remarkable creature, taking pictures and watching its mesmerizing pulsating swimming. It's incredible to think that this creature, that looks so soft and vulnerable, being pushed around by the surge into kelp, is one of the most successful biological designs on the planet - having been around longer than any other multi-oraganed creature alive today. . . . #jellyfish #coldwaterfreediving #thegreatafricanseaforest #capetown #underwater
Opportunities for further study
As mentioned earlier, discovering the pink meanie in its early ephyra stage meant Krish could study its growth rate, which turned out to be really quick – it grew to the metaephyra stage in about a week and a half.
We also had the opportunity to see how its growth rate was influenced by the number of other jellies it ate, eg. by feeding it one or two nightlight jellies a day. We also had time to determine how its growth was influenced by the type of jellies it consumed, eg. box jellies vs. nightlight jellies.
Now that the pink meanie has reached its adult or medusa stage, we are going to determine whether it is a hermaphroditic species or has two distinct sexes, as this will shed light on how such a rare animal is able to reproduce.
Why is the South African pink meanie special?
The particular pink meanie at the Two Oceans Aquarium differs from pink meanies found in other parts of the world.
This pink meanie is also unusual in that it is the only known member of Drymonema which inhabits cold water – all other types that have been discovered inhabit warm waters like the Mexican coast and the Mediterranean.
Interestingly, although more thoroughly studied than our local species, the Mexican pink meanie (Drymonema larsoni), was only discovered in the year 2000. A Mediterranean relative, known as the "Big Pink Jellyfish" (Drymonema dalmatinum), has been known to science since the 1800s, but when spotted in 2014 it had been almost 70 years since the last sighting. These jellies are incredibly rare, and this new South African species is no exception.
Our first pink meanie (ever!)
In August 2017, the first pink meanie to ever be displayed in a public aquarium was put on show on the Two Oceans Aquarium Jelly Gallery. Like our recent addition, this pink meanie was also an accidental discovery – eating its way through a pool of compass jellies that we’d collected for display.
This first pink meanie taught us a lot about these incredible animals – and we are looking forward to having another chance to learn about the lifecycles of animals that are so intimately linked to the blooms of other species on our coast.
Feel free to leave your pink meanie related questions in the comments and we’ll pass them on to jelly expert Krish Lewis.