[Octopus]: Mercatoris Manor

sedna

Architeuthis
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O. mercatoris is not my favorite kind of octopus to keep. I've always found them to be a bit boring, but Tom stopped shipping the larger ones after so many losses with this cold winter. I've really been wanting a shot at raising large egged octos, and Tom hadn't had one merc die in shipping, so I got 4. Yes, I got 4 O. mercatoris from Tom to put into my 20 gal tank. Yes, I was worried that this was a stupid move, while we know mercs can live together, I'm not sure 4 in 20 gals is the best move. BUT, I have other tanks and can re-home anyone not behaving…

They came on Tuesday, and the first problem was acclimating that many. At first, I just slit holes in their bags and dripped that way until they were full. Then I put them into small glasses for the duration so they'd be easy to move. They dripped for 3 1/2 to 4 hrs. They pretty much all found a spot to hide as soon as they were put into the tank. They were boring. Until the lights went out and the nocturnal shenanigans began…

One went right into a hole and covered itself with a shell. It has stayed there ever since, I've only seen her come part of the way out of her den, so I called her "Scaredy"- I wasn't sure what sex she was then. She keeps the classic merc pose, peeking out of her den, keeping a shell for a door near by.

"Bully" started getting into fights with anyone the minute the white lights turned off. He and "3 of 4" (I know, real creative- like a Borg designation) are the same size. Bully tried to pull Scaredy out of her den, but she wouldn't budge. Then Bully got into it with "3 of 4." They were beak to beak and I was freaked out. They looked for all the world like they were having a slap fight, arms flailing all around and mantles huffing. It was over as quickly as it began. As they were getting into it, I noticed the smallest, Midgie, climbing on the glass toward me. I was worried for the tiny one. Bully disengaged and then went back to Scaredy, when I realized that he wasn't trying to pull her out, he was trying to slide his third right arm into her den…

All that time, Bully is going back and forth between Scaredy's den and 'fighting' with 3, and Midgie is inching closer to me. Then Bully gave up on the other two, and was on the same wall coming toward me. I was worried for little Midgie, until he crawled right up to Bully and tried to start something! I was even more surprised that Bully ignored him!

The next night, Midgie proved his masculinity by making his own rounds to Scaredy's den, and trying to slide that third right arm through her shell "door."

So it has gone every night. They all have their own dens, and I can find them every morning. There is a time at night right after the red lights come on and I can see all three of the others out, but then on of the bigger ones hides. I can always ID Midgie, but if Bully and 3 of 4 are both out, I can't tell them apart. I'm not even sure it's fair to say that Bully really is a bully, half the time it could be 3. Midgie is actually the most brazen, comes right out onto the front glass every night to see me, and seems to be the one most likely to start fights.

I don't really know what to say about the fighting. It never lasts long, it never seems serious, and I can never tell what it's about. They aren't fighting over dens or food. After four days now, they are stick feeding (except for Scaredy who blew her food away last night), they have their own dens that they return to… I'm not worried yet, they are all in fine shape and they haven't hurt each other at all.

Finally, I am finding mercs to be kind of fun!
 

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Some explanations on the pics… Obviously the one is the whole tank. Scaredy can always be seen peeking out from her den in the lower left corner. You can see her in the middle pic. Bully and 3 live under and in another rock, one of them under and one of them in a rock cave. Midgie lives in the middle of the tank, under the right side of the same rock that Scaredy lives in. I know they are incredibly stupid names. They are really more for identifying them in posts than some really good pet names.

The egg crate that is magneted to the back wall with shells on it was to provide a hiding space for 3 of 4 the first night when he seemed intimidated by Bully, but it hasn't been used or needed since. I'll get a nice frag of some non stinging something to make it more interesting.
 
This will be interesting for not only the quantity you are keeping in a 20 (I easily kept 2 sibblings in a 15 and 3 sibblings in a 45 but) but for the combination. The three I kept together included one female, the pair ended up being two males. The two male tank (Sisty and Dusa) was my most successful merc tank as far as interaction. Of note, one of the males eventually disappeared (MIA) in the larger tank long before the other two died. Miss Broody never left her den from the moment they were released to the tank, Sleazy (lone wild caught, never mated female) was the same way but Trapper (WC) did not take her brood den for several months. Interestingly, HideNSeek tried to mate again with Miss Broody after her fertilized eggs hatched. She wanted nothing to do with him, left her den after he pestered her and died after sealing herself in a new den for longer than a month.
 
WEEK ONE:

It's been one week and all 4 octopuses are still alive. I usually don't even start a journal until the two week mark and acclimation is finally over. Cautiously, I report that they all seem to be doing just fine.

The "fighting" stopped after the third night. I'm not sure it's fair to say it was fighting, as no one was ever hurt and there never seemed to be any intention cause physical harm. I think it was all about establishing territory… Of course, who knows what they do after I go to bed? Midgie comes out and dances on the left side wall and left front of the glass. One of the bigger ones stays to the right side, and the other big one stays toward the back. I never see Scaredy out of her den, but she must at least reach out because some mornings the shells by her den are rearranged.

I'm not sure if 3 of 4 is male or female, but it and Bully seem to "hang out" near each other. Not really interacting, but they seem to stay within 10 inches of each other. They can pass close by each other with no more "displays" or fighting or whatever that was. Midgie seems to keep his distance, at least at night.

Here is the weirdest part- they den within INCHES of each other!!! They don't have to. There are plenty of places to den up, lots of porous rocks with holes, they could even be farther apart under the rocks, but they aren't. The farthest apart any of the dens are is less than 18 inches, and that's only because Scardey took the first available spot and never moved. The other three dens are within 6 inches of each other. They actually moved their dens closer to each other over the course of the week. This morning, AFTER the nights were on, there was some more den hopping, resulting in the animals close together, not farther apart. There seems to be no need to have a large space between the dens at all!
 
Sisty and Medusa always denned very close together. Miss Broody stayed in her originally chosen barnacle (which happened to be where they were all hatched) and the two males chose to either den in one of the other openings in the barnacle cluster or somewhere in the back (at least when I could find them) of the tank. The two males in the larger tank moved their dens every couple of days, staying (if I am remembering times correctly :old:) no more than a week to 12 days in one den but returning to previously used dens often. The two males in the smaller tank (Sisty and 'dusa) shifted dens but there were limited choices and I paid little attention since they were out and waiting for me at 11:00 each night for feeding and general tank activities.
 
The residents seemed to have settled into a routine. Scaredy never moves from her spot, always peeking out, everyday a different shell for a door or the shells right outside her den re-arranged. For the rest of them, some nights are more active than others. This may also have a lot to do with whether someone left a light on later...

I have an ongoing issue with the people I live with (my daughters and husband). They seem to think they need lights on in the living room as they move around after dark. Apparently, they like to be able to see where they are going so as not to run into things. I can't understand why they just haven't memorized where all the furniture is, so that the tiny amount of red light thrown off the tank isn't enough? Why can't they just suck it up and deal with stubbed toes or tripping over sleeping dogs? I've sacrificed so much for them over the years, why can't they appreciate that nocturnal animals only like to come out in the dark?

On school/work nights, I do get more dark time in the living room and that's when I see the most of the Active 3. Midgie is curious enough to come out if the only light is the TV. He'll hang out in a corner that has a lot of coraline algae so he thinks he's under cover, and watch us watching television. He's still the most brave, the other night he "crawled" across the surface of the tank to get to me quicker. Bully will come to the front of the tank, but he still takes the slower, more cautious approach.

I just appreciate that they come out at all, they are the most active bunch of mercs I've ever kept. These guys are actually changing my mind about O. Mercatoris! I kind of wish I had another open tank for some more!
 
I remember @Animal Mother mentioning that his first octopus, Einy, seemed to do much better when there was activity around him. I would not put an octopus cage inside a predatory tank (even though Einy did fine) and, at the time, we did not know mercs could live together (there have been a lot of failures with other species) but there is a lot of anecdotal evidence that suggests octopuses are more active if they can at least see other aquatic animals. Even in the case of different octopus species, I have seen mine dance with each other across the room and my singly kept mercs have been far more reclusive than mercs kept in pairs (at least with the males, the females have been stationary but visible when there are things to see). Recently, in a remembrance of Roland Anderson, @gjbarord mentioned that Roland, half jokingly, suggested adding a sea lion to an octopus tank might be the ultimate enrichment. The sentiment is the same I think, an active aquatic environment is more likely to induce activity.
 
I think I "interrupted something" this morning… The dogs woke me up for their 6:30 breakfast and bathroom break, so I was octo watching until they were ready to let me go back to bed. BTW, the dogs can appreciate keeping a dark living room! The only time Bruce the Airedale ever walks into things is when he's not looking (it's kinda funny to see).

Anyway Bully and 3of4 were in the back bottom corner, it took me a minute to realize there were 2 of them. By the time I got my eyes focused to the red lighting, I could see that they were both on the wall, one sort of on top of the other, higher up the wall. By the time it occurred to me to try to figure out if 3of4 really is a girl, all I could see was arms "disengaging" and 3 skulking away. Oddly enough, Midgie wasn't out anywhere. He's usually first one out and last one in.

I wish I could get pictures of the activity, but we all know what red lighting does for our pictures. I can try anyway, now that I'm now so worried about spooking them. I have hesitated reporting this because I have no proof, but every once in a while I think Bully and 3of4 are in the same den all day. It's a very large space (compared to them) under one of the rocks, maybe it's big enough for 2 dens as far as they are concerned!

D, I would say that all of us in my house have seen larger octopuses notice when there are fish in the tank across the room. We have joked that they are trying to memorize the floor plan so they can escape and get a fine fish dinner! Anyway, I'll never keep only one merc at a time, if I can help it!
 
When my first 5 merc hatchlings were outgrowing a single breeder net, I tried to study them to see who got along best in hopes of creating two sets of breeding pairs (assuming 2 females and 2 males and a whatever). Two of the animals always chose to stay close together and mostly lived in a set of barnacles that were attached so I put those two in one net and left the other three together. The two that had always denned close together were eventually moved to their own tank and Sisturus matured enough to tell he was male (curled third right arm and enlarged suckers). For at least a month longer, I was sure Medusa was female and I had won the guess the sex game. Medusa fooled Sisty as well and I have poor photos of him trying to mate Medusa at this stage. Eventually, Dusa matured (and got a slight name change) and was clearly also male. They always did well together, Dusa being more shy but following Sisty's lead. I only ended up with one female so I did not redistribute the mix. Sisty and Dusa often shared the same den inside the rock but usually took separate, close quarters when they denned where I could locate them. In both sets of mercs and with my singly kept animals, the females chose a den and stayed put where the males would change dens every week or so.
 
Well, I think I could rename "3of4" to "Roxanne-" like the Police song. There has been lots of action once those red lights go on for the night!

The other night I was watching Midgie, he was on the front of the tank, I assumed looking back at me. He was dancing on the glass and following the dull flashlight for a bit, then he stopped dead. He strobed very clearly, 3 times. Very deliberate, starting at the base of the mantle behind his eyes, slowly moving to the mantle tip. I thought he was trying to warn me off or something, but then he unexpectedly took off for the back of the tank. By the time I found him again, he had found 3of4. She was facing away from him, and he had his hectocotylus in her mantle cavity. She was moving away from him, sort of dragging him across the back wall of the tank. It went on for a few minutes and they dipped into a dark corner where I lost track of them. Slowly, Bully began to rise up from that corner of the tank, and Midgie seem to be making a quick retreat from 3of4. Bully made himself a large ball on the tank wall, so that he was between Midgie and 3of4. I've never seen an octopus pose like this on the glass. He had pulled all of his arms up and around, like a swirl around his body, and seemed to puffing up, making himself as large as he could. Midgie just sat up in the opposite corner in a pose that I anthropomorphize as defeat. I sat and watched for a while- no "slap fights" or any of the other previously seen posturing happened. Just Bully as a ball on the wall.
 

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