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Brooding Octopus Mercatoris (Jim)


O. bimaculoides
Feb 21, 2012
Ok so I had Jim for about 6 days and then she started brooding in a shell. Two months later, today I go in to find a dead octopus. So I pull out the rocks from the entrance to the shell and a arm comes out to grab me. I did not see any eggs but I am very sure there are some in there. It has been two months so how much longer am I supposed to wait until the eggs hatch? also do planktonic octopus do better in algae rich environments. And when will I have to find some food for them. Their are plenty of copepods and amphipods in the tank already plus who knows what else:razz: also how many of the Mercatoris will survive to live a full life? I hope these eggs are fertilized!

Original Journal: http://www.tonmo.com/forums/showthread.php?28400


Staff member
Sep 4, 2006
If the octopus mated while in the wild there is a good chance she will produce at least some fertile eggs if she broods within 4 months. Here are a couple of older journals with successful broods (we have not seen many mercs for a few years and even fewer females)
Trapper ~8 weeks in tank prior to brood ~6 weeks brood time 6 hatchlings
Varys ~4 weeks in tank prior to brood ~ 4 weeks brood time 25 hatchlings

Both Greg (Varys) and I (Trapper) successfully raised one additional tank bred hatch from the original tank born hatchlings (the journals should have links or info on the tank bred animals and more on timing). With both the WC mother and the Tank Raised mothers, we saw 5-6 surviving hatchlings that lived a full lifespan.

However, why do you think she is brooding? Mercs are very reclusive so her actual brood date (if she is brooding) may be well past the day she disappeared. Looking back a Jim's original journal, I am not sold on the mercatoris species id.

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