[Octopus]: Trapper - O.mercatoris


Staff member
Moderator (Staff)
Sep 4, 2006
Cape Coral, FL
We have our first octo! I THINK his name will be Trapper (family consent still needed) after the nick name of the crabber that collected him. He was a special request from the diver/collector who's site I webmaster and I think he/she is perfect! We are hoping Trapper is a Briarius, are almost certain he is not a mercatoris and hope he is not a Vulgaris (tank size could be a problem).

He shipped overnight FedEx after spending the weekend in his little jar in FL (I am in GA). I opted to pick him up at the local FedEx rather than have them deliver and all went well. He was relaxed white all through acclimation and only showed color when I put his little cup in the tank. During acclimation he stayed at the top of his container with his arms wrapped upward so that only the tenticles showed. The picture I posted under members tanks was the first (and only at this writing) good look I had of all of him as he realized he could leave his little chamber.

He immediately went to the closest dark hole, stayed there a few minutes then came back out and grabbed the small piece of Halmadia that is in the tank. So far he has not investigated the tank but sits almost in the open with the Halmedia held in front of him and tenticles over his head with both eyes visable.

Wish us luck!

Trapper's Offspring

Trapper's Grandchildren
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Congratulations and welcome to Trapper!
We should be able to tell whether he's a briareus or not when we get some more photos.

After almost two months, Trapper is still very recluse but last week he investigated the crab I had in my hand while I was trying to place it in a feeding "dish". He did not touch my hand but slid across the tank, down behind the LR and then made a sneaky crawl up the tank to check it out. Unfortunately, he did not eat take it and left it in the dish overnight.

Yesterday, after several hours and no one present, he took a crab (still only eating dead ones) dangling from an airline tube positioned next to his den. Last night he took another dead crab on the tube with my hand in the water holding the tubing (simple minds - simple pleasures ;>). I am short on crabs (Paul has promised more by Friday) so I didn't try again with my last one (seems two have "escaped") but I did put a small piece of shrimp on the tubing and he examined it, coming 90 percent out of his latest den. I am not sure if he took any to eat. He either decided he had enough interaction, wanted to eat whatever he took in private or was annoyed by the fish trying to pick at the shrimp because he slipped into his den and closed the "door".

Just before he examined the shrimp he very forcefully ejected the crab remains. The empty casing "flew" out of his den at least 6 inches up into the water column.

We are still late into the night/early morning for any kind of visitation (I make myself visible for at least an hour every morning in an attempt to get him to accept my presence) but we have started lights out in the living area for all but the seahorse tank at 9:00 and were able to feed the first crab at midnight but the shrimp interaction was somewhere around 2:00 AM. Strangely enough, he seems less concerned about my hand IN the tank than my attempts to touch the tank from the OUTSIDE.

We still don't know if he is pygmy or something else but we have ruled out Briarius. Mucktopus pointed me to some prior threads and provided a helpful comment on looking for maturity but we never see him in good light (I do think my night/red light vision is improving ;>). What has been peculiar is the parallel with the behavior of Dan's Sleipner (Trapper is definitely NOT bimac). Trapper seems to do similar things about 2 weeks after Dan reports them.

No, but I could hook up the blue tooth to the laptop. Several people have reported octos paying attention to TV's and computer screens. Unfortunately, octopuses don't seem to like each other and don't even manage to get along the way cuttlefish interact so showing Trapper another octo might make him even more recluse. Of course if Sleipner and Trapper of of opposite sex virtual visitations might be acceptable.
It looks like Trapper is brooding now. She moved into a large barnicle shell and has not left it in almost two weeks. She defends it vigoroursly and will now kill a crab if I place it close to the entrance. With a bit of encouragement, she will then eat it so we are hoping she survives until the eggs hatch (assuming there are eggs and that they are viable) The timing of her leaving the ocean and going into the tank is at the far end of possibly having fertile eggs but we will have to wait and see.

I am removing (as I can catch them) the guppies and shrimp from the tank since they would find the babies an attractive food source. I am not sure if I will leave the pencil urchins in or not. They amazed me with their appetite for crab (great for clean-up) but are likely to eat any babies that survive the pelagic stage. I suspect the serpents would be just as interested in babies as food so I am still debating on the best way to attempt to raise any that hatch. I am thinking about trying to catch as many as possible and put them in breeder nets hung in the tank.

Has anyone tried using the nets for babies? I have seen cups and other plastic containers used but not nets.
Merc O'toris Babies

I am not quite sure what to think now :confused: . Trapper has been acting "differently" for the last week so I expected a change of one kind or another. She has been brooding overly long so I did not really expect babies but I put fresh pods in the tank early last week -just in case. On March 17th I was watching her early in the morning and she seemed to "spit out" (like she does crab legs) something a little different :wink: . I woke Neal and we watched for several hours more and one more baby escaped the den, jetisoned similarly. I stayed with the tank the rest of the night but no more babies emerged. I also removed the shrimp and guppy from the tank to minimize any predation (there are still crabs, serpents, stars and pencil urchins but nothing that swims).

I caught the first two and put them in a breeder net inside the main tank. They were "missing" in the morning but reappeared last next night, still in the net. I know there are some small pods in the tank but the babies are not loose on the LR to find them so I have been trying a number of foods (including fresh hatch brine since I make it for my baby pipefish daily, roti-feast, ZooPlex and some tiny baby fish food).

Last night (roughly 24 hours after the first two were released) Trapper acted VERY stressed and was flailing her arms and breathing heavily (similar to her occasional new behavior over the last week but for a loner period of time and more exagerated). I had turned off the power head (actually a pump that sucks from under the live rock and sand to give more circulation) to minimize the turbulance in the tank (the tank has an overflow and sump for its filtration). There should have been plenty of gas exchange without the secondary pump but I turned it back on because of her excessive heavy breathing. She settled back down when the current was restored (it had been off the better part of a day) but there are still no more babies.

Has anyone had the opportunity to watch the hatchings when the mother is present? I cannot see the eggs but the mother is in a barnicle shell that faces the viewing section of the tank (this has been very fortunate since she will only eat dead crabs that are hand fed.) Is it normal for just a couple to hatch before the main group? Is her "flailing" and heavy breathing behavior an attempt to help the eggs hatch (I can't tell if she is using her funnel inside the shell when she does this) or is this a negative sign? Strickly from observation, it appears she is sealing the eggs IN rather than just keeping preditors OUT but last night she withdrew her entire mantle (first time we have seen this) for a few of seconds but nothing came out of the shell.


Reassurance and/or comments solicited :smile:
Octopus lay their eggs over a period of days so it's not too unusual to have some early squirts. There may be a clump yet to hatch. Trapper is behaving in a normal fashion for a broody octopus. The problem with her breathing is that the mantle muscle is weakening so she can't breathe as easily, she'll have been using the muscle tissue as an energy source while she wasn't feeding.

She IS eating. I give her a fiddler every night and I know she eats at least some of it (it varies on how much each night and I try to collect the remains before the clean-up crew does their job so I can see how much she does eat). I started by dangling both alive and dead in front of her den using an air line tube. Over time it turns out that she will only take a dead one and prefers that I just give it to her with my hand. Since I started the hand feeding in stead of using the tube she takes the crab almost immediately (she will blow it away once until she realized that it is supper and is dead).

Also, the heavy breathing comes and goes and is not constant. My thought, with your new info on the muscle change, is that it may be the current and not the oxygen level that caused her to relax since the change was almost immediate.

Is there also a theory on the strange flailing behavior? I have seen this several times over the last week but not to the extent I saw it last night. She seemed confused, like she was searching for something but could not remember what (initially I tried giving her an addional crab thinking she was hungry but she rejected it) or as if she was being sucked into her den by her mantle and trying to pull away from the suction (which did not exist).

As I write the symptoms I am fighting the thought that I am looking at sensenance (sp) and assume it happens to both sexes even though I only see mention of it in males.

I have heard of female octopus feeding after brooding but it generally only extends the life by a few weeks. And yes you do get senescence in females too.

I have seen flailing in healthy octopus and it seems to be assiciated with the shedding of sucker cup skin. So it may be she's trying to deal with old skin. As for the confusion, dementia happens in other animals (not just humans, my spaniel has canine alzheimers :sad: ) so why not octopus?

I'm sorry but Trapper does sound senescent :cry:

5 babies as of this AM

We are up to 5 baby octos (fry?), I think. I definitely have 3 that are alive and seem to eat Cyclopese in a net breeder and saw aother hatch tonight (this one inked when it caught the current) but haven't seen it on the glass to attempt a catch. This hatching is certainly different from the others I have seen where one morning there are dozens of octos swimming all over the tank!

I got bold and tried a small shore shrimp when one grabbed a small bug that was floating in the net. One of the babies grabbed it and appeared to eat it but when I brought another, I saw the octopus release the in tact dead shrimp so I guess it was more of a defensive move than a preditory act.

Jean, you mentioned using a baster and that worked much better than a net (I use them on seahorse fry too) with one problem. Do you have a secret for getting them OUT of the baster? I slowly let the water level fall and he inched down to the water but it took a good 5 minutes to get the little squirt out and then he wanted to hold on to the OUTSIDE ;>).

Also, is there a known air exposure problem with them? I know with the horses there are major issues because of their swim bladder. I believe that octos don't have swim bladders but is there an issue with the skin?
Hi D,

I keep the baster full of water (& squirtling) and put the tip just under the water surface then squeeze the bulb with gentle but firm pressure until it's flat. The squirt should transfer fairly easily like that. As for exposure to air, they don't have many air cavities so decomp (no swim bladder either) isn't an issue, the skin will dry out in these wee guys quite quickly, but there is a species of Aussie octopus (I forget which one) which hunts out of water.

If the squirt holds on to the outside of the baster I usually put it next to the glass (underwater) they'll quite often shift to it, otherwise I slowly move my fingers down the baster (underwater too!) and find that the squirt will often move off rather than come in contact with my fingers.

Hope this helps


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