Monday, August 19, 2013

Carybdea Rastoni Box Jelly Polyps

I've been wanting to get a hold of some Caybdea Rastoni polyps for quite a long time (>1 year!). Well I finally got a hold of some. 

Carybdea rastoni are a variety of smaller Box jellyfish with four tentacles, and which range in the Pacific Oceans from Japan to Hawaii. In the places where they are found, the jellies can be seen in pretty large smacks. Carybdea rastoni are very proliferate and can actually be invasive. Their sting is painful, but not lethal. I don't plan on handling these with my bare hands like I do with see nettles! 

The polyps of carybdea rastoni are a little surprising. From research, I understood that they were small, but I was surprised at just how small these polyps really were. They are better viewed under slight magnification. I would say each polyp is about the size of a newly hatched Brine Shrimp. Interestingly, these polyps can open their mouths extremely large, and shove a whole baby brine shrimp inside! For that very reason, I am simply feeding them Brine Shrimp for now.

I haven't gotten any good pictures of these polyps because they are so small! Here is one off the web, from Jellyclub.


A few juvenile medusa came with the polyps. They were very interesting to look at. At around just a few mm they have the beginnings of 4 tentacles. As the pulse around erratically, they kinda become cute... in a dangerous way. One of the reasons you don't see these guys on display is because they are very hard to culture. It isn't entirely clear as to what they eat in their earlier stages. The Two Ocean Aquarium in South Africa has managed to raise wild juveniles up to adults on public display. They feed live Mysids to them. That appears to work really well. Unfortunately, the juveniles are far too small to eat them. They need some other food to feed on. I'm going to try feeding Rotifers to them, as brine shrimp seem too big to deliver much nutrition. I ordered a live rotifer kit (we will see how this goes) and I will start culturing Rotifers. 
 
I also want to experiment with making a gelatinous food for them, and other jellies. Apparently agar and gelatin have been used to feed jellyfish before. Perhaps I can create a very nutrient dense gel for jellies.

Sorry, but these polyps and jellies will not be for sale or trade. I know they aren't lethal, but they are dangerous and also very invasive. If a public aquarium or research institute of some sort wants these, something could be arranged. 

I'm going jellyfish collecting this Thursday. I'm hoping to find some more Sea Nettles (both of mine are male) and possibly some Chiropsalmus box jellies and Cannonballs. 


Wednesday, August 7, 2013

Pet Box Jellyfish


The title explains only one of three cool finds I made in South Carolina recently.

I took a normal beach trip in SC. I wasn't expecting to find much where I was. I ended up finding quite a lot more than I expected.

Box Jellyfish- This will probably be the most popular of my finds. I found two Box Jellies (Chiropsalmus quadrumanus) washed up on the beach. The first one I found was gravely injured and torn up pretty badly. I preserved it in alcohol. The second one I found had washed up just seconds before, and was very much alive. I bagged that one up immediately. Atlantic Box Jellies are fairly rare, and this was a big deal to me. I've never seen any live box jellyfish before. These have to be the most beautiful jellyfish I have ever experienced. They are an actual blueish color. The pulse strongly, and have these arms of tentacles at each of their four points. I got the jellyfish back home, alive. It died about 2 days after I caught it. This isn't an un-normal thing for box jellyfish to do. They don't often do well in captivity. The jelly began to stop moving and eventually sank. It began to fall part at this point. I saved some of its gonadal tissue to examine. It was in fact female. I intend on catching more eventually, and figuring out what they need to survive in captivity. It may have been that I found an old or death-bound specimen. I left the tank it was in running. Im hoping that maybe there are some polyps in there somewhere. After all, it was female...

Box Jelly eggs. 

Cannonball Jellyfish Juveniles

As you may know, Cannonball jellyfish are very common in the Atlantic Ocean. What isn't common are Juveniles of these jellies. You often see specimens that are tennis ball sized or greater. Well, while I was at the beach, hundreds of baby Cannonballs were washing up. Some were the size of quarters. This is unheard of to me. I have seen one image online of Cannonballs that were around the size of a 50 cent piece.
video

Most of the jellies were very badly beaten up. Some were cut in half or had fourths taken out of them. Surprisingly, the majority were still alive though. I kept three specimens that seemed to be doing well. One appears to be the smallest wild cannonball ever seen before. It is about 1/2 an inch long and was smaller when I found it. This one is doing really well. It pulses around the tank actively. The other two were damaged and they seem to be going downhill slowly.

Atlantic Sea Nettles

There were also a number of Sea Nettles present. Many got beat up in the surf, but a few lived. They seemed to be stinging people in the water towards the end of my trip. At one point I was even stung while I was simply swimming. I was stung many times afterwards when handling live specimens. Right against the area where water and sand meet, I found one live Sea Nettle. This thing is a monster! I wasn't even aware that Atlantic Sea Nettle could get this big in the wild. I moved it into a bag with my hands and paid the price. I have been stung by Sea Nettles many times before. This sting topped it all. Perhaps it was the size, but it got me good!

video


I ended up moving my two Sea Nettles into my 20 gallon DIY kreisel tank. They seem to be doing well there. The smaller one is doing especially well. They keep shedding tentacles, however. I worry that the tank is just a hair too small for the larger one.

The Cannonballs got put into the cylinder tank I made reccently. They are doing well in that right now.

I have a surprise that should be arriving next tuesday. :)