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O. mercatoris


Aug 31, 2010
I got this girl from one of my local distributers. They got her in a few days ago and by the time she made it to me , she had laid eggs in the pipe she was in. So obviously I don't expect to get a whole lot of time with her, but maybe I could try to raise the eggs. :bugout:


GREAT pictures! The young are alive so this, although different than what you wanted might be an even better experience! With siblings, Greg and I both found we could house at least three together and they will inbreed successfully. If you have too many, I suspect you have no problem with how to home them but GHolland and I were only able to raise 5 from each hatching, regardless of the number of eggs. HOWEVER, she did NOT lay these "on the way to you". These are close to hatching. I am jealous!
Hmm. I was told they were just recently laid and they didn't want them to be separated. Whatever though... I'm going to be reading through your journals and try to get a game plan. Any insight looking back you care to share? And how long until they hatch would you say?
I never saw the eggs for either of the broods I had but I can tell just looking at the one you posted that it is close to hatching. I did get to watch two different O. briareus eggs and know it is several weeks before the eyes are even visible. When they hatch they will look like a bunch of little white hungry ticks. Look at Trapper's hatchling and her offspring's hatchlings to see how closely these already look to new hatched octos. Have you kept the loose egg where you can watch it? I don't know what chance it has but you might look to see (I can't see it in the photo) if there is any yolk sack left). If these are typical, the yolk sack will look like a yellowish ball placed between the arms.

I fed mine daily with a pipette (two times might even be better if you wake up early enough) of mostly FROZEN (NOT dried) Cyclop-eeze and then added shore shrimp. Check GHolland's journals on Varys and her offspring for anything else he may have used to feed them. Our results were about the same but we used very different housing (Greg used small tanks where I used a large tank with large breeder nets).

I looked back at your pictures again to put in a vote for hatching and noticed that the first picture seems to show a yolk sack that is still quite large. The next full moon is March 27th so I will throw my guess there but suspect sooner. Expect only a few on the first day, a bunch on the second or third and then a few more over the next 8 days or so. The one thing that may disrupt is the acclimation. If you can cool you tank (leaving the lights off will help, a fan might be good or open a window but you don't want it cold, guessing around 74-75 might be about right. After hatching, warmer water MIGHT be helpful but can't say for sure.) this might help to get them to stay in the egg until the yolk sack is fully consumed (cuttles born with a yolk sack have never survived, I don't think we have any records of octos hatching this way).

The full moon has passed and the next is not until the 27ths so I am in the pot for the 25th.
I hope you have many babys. If you need to place any let me know. I live within an hour of you. I think my merc is a male and an adult but i am enjoy him very much. I have had a Vulgaris. I now have a merc and an briareus. I had the vulgaris 12 years ago and wanted the same one. was told by a lfs that the merc was a baby vulgaris. Now I have done a lot of research and know the difference. I see you have been a member for some time. Have you had many?
I had not thought of being able to put the pipe in the but it sure would save a lot of trouble catching the hatchlings.

Did you get the net yet? It is pretty big and if you put the floor to be near the bottom, rather than near the top (the split is about 1:3) it may fit and be totally submerged. An alternate to maximize the depth would be to place the grid all the way to the bottom so it just sits on the frame and not on the pegs. If you decide to try putting the pipe in the net, you MUST do this fully in the tank.

One thing of note and I don't know that it matters but she will jet them out of the pipe using her siphon ( I remember journaling that I thought one of the females was eliminating waste but the waste turned out to be a hatched octopus :biggrin2:). With the platform all the way to the bottom, this may not be a problem. You can use the grid floor to zip tie the pipe to keep it stable.
More than I ever saw of my merc eggs! Watch for them to flip in their egg casings. They are supposed to flip twice and be close to hatching when they are reoriented with suckers near the stalk. I journaled one flip with Kooah's brood but didn't observe two.
Got some hatchlings between last night and this morning. The things are so tiny... :lol: My camera wouldn't focus on them so I had to try my phones camera, and I was only able to get this one half decent picture, the snail shell gives you an idea of size...