[Octopus Eggs]: Legs - O. Mercatoris

Britani

Cuttlefish
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Dec 3, 2014
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Florida
Oh My! We realized 1 week ago today that our "boring" octopus, Legs, isn't actually boring, she is brooding!! (We just began the adventure of keeping an octopus in January 2015, and while we've read everything we can find about mercs on TONMO, any additional thoughts/insights would be greatly appreciated.) A brief recap:

3/18/15 - I surprised my kids by picking up a new octopus (our previous one had died a month or so earlier) at The Fish Collection in North Miami Beach. Legs was $29 and sold to us as a "small" atlantic octopus (seems to be the common terminology here). After some research, my best guess sis that she is an o. mercatoris.

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4/10/15 - Over 3 weeks since we got Legs, and while she happily accepts crabs that my son hand-feeds her we have never seen her outside of the den that she chose the first day she came home.

4/12/15 - The Fish Collection said that we could bring her back for store credit as our kids were really wanting to get another active, fun to watch octo like our first - best guess was that he was an abdopus aculeatus. We decided to take her rock out of the tank to see if we could persuade her to come out of her hole when we realized that she had a very good reason for staying in there - she had laid eggs!

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4/13/15 - Legs will still accept a hand-fed crab and we are able to watch her clean and care for her eggs, but we can't get a good enough view to see if they are fertilized. (However, I think I see eyes in this picture.)

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4/14/15 - This morning my boys and I all think that we are seeing eye spots, but a photo taken this afternoon confirms it - they eggs are definitely developing!

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Legs' Journey continued...

4/15/15 - I added a bottle of live tigger pods to the tank today to see if we can begin to stock up for when the hatching occurs.

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4/16/15 - I ordered a MarineLand accent LED lighting system - 660NM in red so we will have red lights to view Legs and her hatchlings.

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4/18/15 - It appears that some of the hatchlings have turned in their eggs and have their legs toward where the eggs attach to the rock.

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4/19/15 - It seems as if maybe some of the hatchlings are moving in their eggs, but it could just be that Legs is moving? Some of the hatchlings seem to be taking up much more of the space inside of the eggs and it's hard to see how much of the yolk sac might be left.
Specs: We have a 29 gallon BioCube with only Legs, a conch, a snail, some starfish, and a scallop as residents. I have purchased two breeder boxes to float in the top of the tank with some of the hatchlings, and was contemplating trying to find a breeding net too, but I am unclear as to how the hatchlings will stay in the net without a lid (the boxes have lids). We have shells ready for the hatchlings to use as dens if we place them in the breeder boxes, as well as another bottle of tigger pods in the fridge and a long dropper to use to feed them. We did our best to "octo-proof" the tank by cutting a piece of plexiglass to fit right under the lid. I am on my way to Home Depot now to see if I can find a very lightweight piece of screen that we could use to block the holes to the filter. How do I know if any of the tigger pods are still in the tank? What else could I stock the tank with to have food ready for the hatchlings?

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Any thoughts on how much longer you think we might have to prepare before they hatch/what else we need to have ready when they do hatch would be greatly appreciated!
 
From prior journals and a bit of experience, the larger egg species tend to take 8-10 weeks (only about 3 for small egg species), temperature seems to be a major factor in hatching time but I have not seen anything relating success of the hatchlings and time in the eggs. It is also hard to be precise since it is often not clear when the eggs have been laid. Usually, the keeper will notice the animal stops coming out or stops eating and eventually figures out what is likely going on (or spots eggs). I (:oops:) never saw either of my mercatoris females' eggs because they were so well hidden.

It is hard (scientifically improper) to generalize with only a small sampling but my female mercs found dens and rarely left them even before brooding. When my generation 2 female was released from her breeder net, she located the shell where she was hatched and I never saw her leave. He brothers would visit the other shells in the group (and her) but only stayed a week or so before relocating their dens. Den changing was also true of the two other males from the brood that were housed in a smaller aquarium and not true with at least 2 other females that never laid eggs.

@sedna is currently expecting hatchlings with Mama so watching her timing may be helpful.

@gholland probably has one of the most complete sets of threads for the merc (albeit older threads). Here is the beginning of the adventure with Varys . The journal links forward to the offspring journal on the last page. Greg and I had hoped to do a swap to add new genetics but neither of us had a good grasp on the sexes of the 3 generation early enough to accomplish the mix (and the survival count in both cases was low, with only one female).

I used a breeder net that had a hard partition (for the shells) and did not have much problem keeping MOST of the hatchlings inside. In the first group one crawled up the tank wall and died but the other 5 stayed (eventually I went to two nets) until I released them. In the second batch, I had to recatch some of them and one of the surviving (Wiley) never did live in the net but survived on his own in a 45 gallon tank. Unfortunately, it is almost impossible to find frozen Cyclop-eeze today (the brood stock is wild and suffered a major failure several years ago). The freeze dried may still be available (but hard to find) and can be rehydrated (which is what I think I see being sold in cubes). I am not sure how the freeze dried compares with the original frozen. If you have a spare tank (water and filter only - no need for LR). Getting live shore shrimp to feed fresh as they become the size of the shrimp was successful for me (you will likely have to kill the shrimp at first). They may take frozen at some point but I would start with freshly killed, then work with live and then crabs.

Good luck and please continue to keep us up to date :biggrin2:
 
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4/20/15 - This morning the eggs seemed to look fuller, or swollen, but by this afternoon they were looking normal again.

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4/21/15 - I am surprised by just how much detail we can see even though the babies have not hatched. There is a large difference in development within the eggs, some of the embryos are fully formed, while other eggs only have eye spots. We added another bottle of Tigger Pods today and installed a red light. Legs is still eating when hand-fed and will wave her tentacles out of the many holes to her den as if to get our attention and ask for more food.

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4/22/15 - We did a water change today and adjusted the water slightly - the salt content had risen slightly over time.

4/23/15 - We ordered 250 copepods/amphipods today from Reefs2Go - should arrive tomorrow.

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An anecdotal note on water changes after the hatchling appear. I did not notice this so much with the mercs but with the O. briareus, it "seemed" that I had noticeable die-offs right after water changes in the smaller environments. I don't think this was the case for the animals in the primary tank though. If I have to opportunity again, I would use the water in the display tank to change the water in the smaller tanks rather than using newly made saltwater. Again, this is anecdotal and not properly documented but I am not the only one who thought they observed this. If you leave all the hatchlings in the main tank, I don't think the quantity of water during a change would have as much of a possible effect but you might do smaller, more frequent changes than for your normal routine.

You can expect at least a 10 day hatching period with the majority of the eggs hatching somewhere in the middle. It is possible that it could take longer since you are seeing a noticeable difference in the eggs.
 
4/24/15 - Holy Hatchling!! We have our first hatchling (at least that we've seen!!). I was trying to take a picture of Legs and the eggs around 11:00am, when something "floated" by in front of my lens. When I moved my phone to look, it was a baby! It did land right on the side of the tank, just like previous journals reported, so we were able to catch it in a cup and keep it safe until we finished the necessary adjustments to the tank. We quickly hadn't expected hatchlings for another couple weeks (we have had Legs 5 weeks and 2 days today), but quickly finished our last "to-dos". We have a covered the filter intakes with a piece of tulle and now have a breeder net in which we placed a variety of shells and the hatchling. We started with a breeding box, but the hatchling swam right through the slits and out into the tank! We also received our shipment of amphipods/copepods today, so added them to the tank as well, along with piping some more tigger pods right next to the hatchling, though it didn't seem to take much notice of them. Here are some pics of the first hatchling - it's worth noting that the coin in the picture is a dime - the hatchling is SOOOOO small!

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4/25/15 - We saw one more hatchling on the glass today around 11:30am - we were running out the door so we made the choice to leave this one free in the tank (after checking that hatchling #1 was indeed still in the breeding net) but once we came home we have not seen it again. With the amount of live rock in the tank there is a good chance we may not see it again - it's amazing just how well they can camouflage and, given their tiny size, it would take a miracle to see it unless it comes to the glass again. Hatchling #1 is still doing well - we took one of the shells in the net and coaxed it inside (it was using the blue plastic pieces as it's den which made it VERY hard to find) and it has stayed in or on the shell since. We were able to pick up the shell and add some tigger pods directly into the shell, so we know it had the opportunity to eat, but didn't observe any eating taking place. I did notice (if you look closely at the first picture above you might see it) a small yellow spot in it's mantle yesterday (could that be a little of the yolk sac?), and I don't seem to see it now, so maybe we will observe it eating soon? As a side note, our tank is set at 78 degrees, I wonder if this could have played a part in some of the eggs beginning to hatch after just 5 weeks and 2 days vs. taking 8 - 10 weeks? We added another bottle of tigger pods today - now we can see some hanging out in the corners of the tank near the sand and swimming around, so we feel confident there are enough in the tank for any new hatchlings to be able to catch some for dinner. The copepods/amphipods were considerably larger than the hatchlings so for now we are going to stick to the tigger pods. If you look closely you can see hatchling #1 hiding in this shell - it's barely visible due to turning completely translucent when it's in or on the shell.

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DWhatley - thank you for your observations on water changes post hatchlings! We were just discussing how to handle this today and decided not to do a water change quite yet, so now we will make smaller changes based on your observations just to try to minimize the risk to our newest additions to the tank!
 
It has been quite awhile since I had the opportunity to raise hatchlings so I hope I remember most of the successful outcome adjustments. See if you can get your hands on some Cyclop-eeze (you won't find the original frozen but may find rehydrated (or at least that is what I think it is) or dehydrated (that you can rehydrate). There are also some other manufacturers for the dehydrated (but don't get the dried food that says it has it as part of the mix). This is the only food I know was successful (but look back at GHolland's Varys journal to see if he found an alternative) for the first few weeks. After that, feeding was simpler and I fed freshly killed shore shrimp. I don't have a lot of confidence in their hunting at this stage but the more you can observe and record, the better for all of us. I also fed at least twice a day and three times may be beneficial for the first month. Once they can handle small shore shrimp (you can try frozen mysis but I recommend avoiding Hikari as it appears to be too sterilized and not have enough smell to attract many animals that are accustomed to eating dead (the texture is almost of being steamed). I would recommend PE mysis if you want to try frozen (see what your local LSF or Big Fish store has in their freezer). I've never had a lot of success with table shrimp with the mercs but my last one (Sleazy - don't ask :biggrin2:) did accept it as an adult IF I offered pea sized chunks. Prior failures with table shrimp may have been a size of offering issue rather than the shrimp. GOOD LUCK and please do keep us posted!
 
04/26/15 - Unfortunately, hatchling #1 did not survive. We found it in the breeding net this morning, but it was dead. Last night it was sitting on top of it's shell just rocking back and forth with the small current from the filter, which was different from before when it would spend it's time hiding.

DWhatley - I know our local fish store has frozen Cyclop, would that be the same as the cyclop-eeze? If we leave some of the hatchlings (assuming more hatch) loose in the tank, how do we feed them the frozen food? Just add some to the tank and assume they are eating it? Any recommendation on how much to add? Thank again for all of your suggestions!
 
I suspect any tiny (about the size of the tip of a pin) crustacean will work but the branded Cyclop-eeze had been used for years for raising both fresh and saltwater newborns (fish as well as other animals) as well as corals so I have not experimented with other foods. A couple of years ago their breeding population crashed and has never recovered. I do think you need to feed dead (no harm in adding the live, I just don't think they catch enough of it). I suspect they scavenge more than catch while they are young.

I do think size matters :wink: (possibly for introduction of all new foods - it does seem less important after they are adults and accustomed to eating what is offered). If you have little ones in a net, enough will likely enter the water column to feed the escapees but you will want to add the larger size to the tank (you will want a clean up crew) as they progress. Wiley refused to stay in the net and I often thought he died. Eventually, I stopped feeding the tank and only then (as an adult) did he finally come to the front allowing me to discover he was still alive and to capture him and put him in a smaller tank (where he lived out a normal life span).

We only have a very small sampling but in all cases where animals survived and lived a full life span the count was 5 (the number of eggs and hatchlings did not seem to matter). I have no idea what the survival rate in the wild is (the generally accepted number is 1% but this is a guestimate that is often repeated without any statistics).
 
04/26/15 - We fed Legs another shrimp today and as I was waiting for her to spit out the shell a hatchling came swimming by. I watched it until it crawled into the rocks in the back of the tank, and was amazed to see "it" coming around from the other side again. I think there might have been a second hatchling loose in the tank that we were unaware of (this would make 3 hatchlings so far). This one/these seem to be bigger than the one that died, and they seem to be more active as well. We were face-timing with my mom so she could see the hatchling and she asked to see Legs - and while watching Legs and the eggs she and my son saw another hatchling come flying out of the den! As best I can figure we're up to 4 hatchlings with 3 surviving at this point. As of now I think we're going to leave them free in the tank as the only one we know we've lost was in the breeding net. We bought some frozen cyclops, so we have thawed some and added that to the tank by using a dropper to blow it right around the hatchlings and outside of Legs' den.

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You might try blowing some directly to Legs as well. After Trapper's baby hatched, she would only eat Cyclop-eeze but would come up to the pipette to feed (I have a video of her eating it. I'll locate it on YouTube if you want to watch and have not already seen it).

Keep watching for Legs to blow out more hatchlings. They look jet propelled when they are evicted :biggrin2:. It is likely that you will soon see a batch of them come out all at one time.

You mentioned that the first one seemed to still have a yolk sack. This is never a good sign and means they hatched prematurely so I would not discount trying the net again based upon this. If there are enough, try both leaving some in the tank and some in the net with shells.
 
Thanks for the suggestion - we will definitely try the net again if we get more hatchlings. I would love to see the video of Trapper if you are able to locate it.

We decided on one last feeding tonight - we blew some cyclops to Legs and then around where we had previously seen the hatchlings. Before too long one seemed to just appear out of nowhere. I wonder if it came out to eat? Haven't seen the others again today, but hopefully they will get used to this routine and decide to come out when we remove the lid of the tank for feedings.

Question: You mentioned getting a clean up crew - we definitely need to add some, the starfish help, but I don't think they will be able to keep up with us feeding the frozen food. What do you suggest that won't be a threat to the hatchlings? We were talking about snails, hermit crabs, and a red brittle star, but aren't sure if it's safe to have them in the tank while the littles are so small. We took the conch out for now as we were concerned about it bothering Legs, the eggs, or the hatchlings. It hadn't seemed to be a problem before, but last night was crawling on the rocks right at the opening to her den so we removed it just in case.

What would the yolk sack look like if it wasn't fully dissolved? Would it be in the mantle like what we thought we might have seen with hatchling #1?
 
The yolk sack will look like a yellowish ball held in the arms.

I tend to use snails for algae but they won't help with meaty foods. My favorite for getting to the meaty foods in cracks and appear to be safe even with the hatchlings a serpent or brittle stars (avoid the green as they will eventually become aggressive). Some starfish can be aggressive and trap their prey and the ones that are not meat eaters, won't help. The serpent and brittle stars eat differently and bring food to their mouths (vs bringing their stomach to their food like most meat eating starfish). Crabs are good for cleaning but, again, the safe hatchling safe animals are algae eaters (porcelain, mithrax) and I am not sure how safe hermits (that are very aggressive) would be (I don't use hermits and don't like them but many find them helpful).

Here is the video of Trapper eating Cyclop-eeze after her hatchling hatched:
 
04/27/15 - The "triplets" were all out this morning - no idea if these are the same three that we spotted yesterday, or if there are more than three in the tank. We caught one and put it in the breeder net this morning and piped some cyclops to all of them as well as to Legs.

I am going to start looking for a brittle star to help with clean up. I read in a different thread a comment about having a red brittle....does it need to be red or just anything other than green? I have found local stores that have brittles, but they said they are brown, not red. I just want to make sure we're doing our best not to add anything that will cause a problem for any of the octos.

Thanks for your help with all of this!
 
The green are the only ones I know of that become aggressive (and for years I swore there were two kinds as the little guy I had was docile for years but ultimately had to go in his own tank because he became aggressive). I like the reds (actually a bright orange to brown and orange striped) particularly well because they seem to have a bit more personality, often den with the octopuses and can be brightly colored (some are more brown or look dull at times). Others that I have kept (and currently have) are a brown/black brittle and a harlequin (attractive black and white striped but very shy). Some of the brittles can become quite large and @Nancy is a bit leary of them but I have never seen mine bother anything. You do need to be sure they are fed, they are meat eaters but I have never seen them catch anything live (including shrimp).
 

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