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[Octopus]: Asian Food Market Octos - Take 2

DWhatley

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Will the eels eat live crabs? :sagrin: You might find another bait crab (sometimes called mud crabs but there are several species used) that would be equivalent.
 
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Am headed down in a few minutes to check - doing a conference call right now but will open a clam up and leave it between the two dens to see if there is any desire to eat a freshly killed versus a clam that died.
 
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Will the eels eat live crabs? :sagrin: You might find another bait crab (sometimes called mud crabs but there are several species used) that would be equivalent.
The eels will definitely eat them as will the lionfish that are in with them... good point and since I've been feeding the crayfish to the eels you'd think I would have thought of that!

Will have to check sources for the fiddlers and mud crabs. I would like to find a place that sells mole crabs - if these guys burrow then these are probably a likely prey item in nature.
 

DWhatley

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Sometimes you will see mole crabs listed as sand crabs on eBay but there are no listings today. I have seen them listed as bait so finding a near by bait shop that keeps a variety might be a major win.
 
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Unfortunately I'm pretty landlocked or I'd collect them myself (the kids and I always have fun catching them at the beach)...

Last night I left a chunk of "fresh" shrimp in the tank in addition to splitting open two clams and putting in another crayfish minus 1/2 of each pincer. All of the offerings remain intact so I decided to bump the temperature up again. I did this late last night and then again this morning, a degree each time. The current setting is 60 degrees so at warmest the tank will get to 61 before the chiller kicks on.

I did see both of them out and wandering this morning and am questioning whether I have a male and female or two males with a missing hectocotylous. What I initially interpreted as new growth on the arm may have simply been me seeing the wrong arm.

Both look "good" from what I expect of a healthy specimen with good coloration, appropriate pupil dilation, and normal movement. I do wonder, though, if there's potentially an issue with having two octopuses in the same tank now. I have not been able to determine what aggression and territoriality these have in the wild since I can't even figure out what kind they are and to date I have not found two potentially healthy specimens (I buy multiples to give myself a better chance of success) but at the same time, I have not seen any sort of aggression between them. They have crawled across each other many times and I have yet to see any displays that would suggest unhappiness with having another octopus in close proximity out of them. I doubt that they are colonial like the Greater and Lesser Pacific Striped Octopuses as I am assuming that with them being a common food product that is harvested in such large numbers that this would not have escaped people's notice, but that doesn't necessarily mean that they are aggressive towards each other.

One way to determine if this is a causal factor in their not eating would be to remove one of them, but without a suitable place to put another one, I don't feel this is a good idea as getting them over the health hump is difficult to begin with. Has anyone experienced octopuses being stressed out to the point of not eating because they are close to another octopus? As I said, I would expect that if this was the case there would be at the minimum some posturing between the two, but there have been no displays that would lead me to suspect problems of this nature at this point in time.
 

DWhatley

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I know O. vulgaris are kept in LARGE tanks together without (much) issue as long as they are about the same size. The tanks I have seen (photos) house between 5 and 10 with very limited sheltering and only the small animals end up attacked. If you are not seeing aggression (quite obvious in some species) I would (holding my breath) continue as you are doing.

I ended up with a boy named Sue (SueNami) because the missing arm was the hectocotylus. I suspect he courted a female that wanted nothing to do with his amorous attempts. The only caveat is that this species (O. briareus) is quite cannibalistic. I was able to mate a pair of these (hatchlings but no survivors after less than a week). Neither animal hurt the other after two pairings but they were siblings and had seen each other across the room all their lives. I am not sure the familiarity was helpful but think it may have been.
 
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Puzzling situation now...

I went down to check on them and witnessed what at first appeared to be one of the octopuses struggling to survive. I then realized it was actually two octopuses together. My first thought was that they were fighting but I didn't see any inking and it wasn't what I would picture an octopus fight being... I continued to watch and then went and grabbed my video camera and put it on night mode.

As I filmed it looked more and more like they were potentially courting or mating. The known male was on the mantle of what I think is the female, similar to what I've seen in pictures of octopuses when the male is delivering the spermatophore. I continued to monitor this and except for the thrashing around, there didn't seem to be any real aggression. Although I was in the dark, I don't think I saw much in the way of color changes in either one and there was no inking involved so I guessed this was not aggression.

When they finally separated, what I noticed was that the one I am guessing is a female seemed to be missing an arm or two, but not sure if this was the same before or if it was a new occurrence. Question - do octopuses... like it rough? Sorry, should have been more scientific and asked if dismemberment was sometimes part of courtship...

What appears to be the 3rd arm looked to be a complete arm that tapered to a tip, not sure if what I was seeing was correct, however.

On the other hand, the "female" seemed to be in pretty bad condition when this was over. Her eyes were hidden away and she kind of just hung there on the wall, but not sure if this is simply an aftereffect of mating in octopuses.

I uploaded almost a 30 minute video to youtube, linked below. For some reason it was not playing when I tried to view it, but hopefully it comes through.

Any expert opinions on whether what is exhibited in the video is courtship/mating or aggression would be appreciated. I did note that when they began to separate and there was some space between them, the known male had his beak out and was "biting" at the water. I don't know if it was also biting the "female" but I did not see any evidence of this on her mantle. This can also be seen on the video. It's long, but hopefully it will play properly and hopefully it also has enough clarity to see what is going on.

 
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Hmmm... Looms like aggression may be the answer. The "female" looms to have died overnight so I will be pulling it and dissecting later on. Will try and do a better job of memorializing the dissection and will search for both eggs and spermatophores. Lesson learned, these species only tolerate close proximity when they are in such poor.condition that they are near death. That said, could also be that the mating was simply too much stress for a weakened female if I end up finding eggs.
 
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OK, not weaving things, but should have said looks above... ipad spell check is terrible...

Anyway, I pulled the octopus and verified that it was a female but could not find anything that resembled spermatophores.

Here's a video of the dissection process. I didn't want to risk dropping electronics into the sink as I dissected (I already had the video camera on a tripod balanced in the corner of the sink) so I didn't know what each organ was exactly, but what I called the crop was the cecum. The "lumps" I described in the mantle flesh were probably the muscles and some of the organs I cut up were most likely kidneys, the darker organs I thought were hearts are most likely not the hearts but the two organs I cut up later that were white colored were potentially hearts...

If you happen to know the anatomy better, please comment and note the time!

 

DWhatley

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Blind leading the blind here but ...
First, here is the link to Cassy's journal when we mated her to Tatanka. You might watch one of the videos to see if you agree that the actions appear similar. This page and the next have photos and videos of two separate pairings. Noting that the knowns male did not suffocate the "female" (one of my concerns with Cassy and Tank since it is a known kill method) I would say you are seeing a mating attempt. The only noted damage to the female (none to the male) was a hole in her webbing but this indicated the beak was involved at some point.

@Neogonodactylus has recorded several "rough sex" observations in stills. In one case (aculeatus), the female totally tore up the male and he has mentioned O. mercatoris matings as being rather violent (oddly, the merc mating I witnessed was not but the sibling had lived together all their lives and this may have made a difference).

Two thoughts about the truncated arms. One is that the "female" suffered damage to the arms with the excessive cold AND/OR she was highly stressed and chewed off her own arms. I have definitely seen this with an animal the exited the tank and was out of the water under a fan. The skin was clearly damaged and he began eating his arms over the next few days, ultimately passing away. I don't think this would be from the bacterial kind of autophagy that is sometimes noted as the known male is unaffected. The other thought is male damage, mostly because of what appears to be a bit in one of the arms. Both are possible.

One further thought is that we have seen male mate with males and Kat's dissection talk mentioned it was common in squid. @Neogonodactylus also just posted a picture of two male wolfi in a mating.

I've been having computer problems and it appears my post never got saved but at least it was autosaved enough to complete it from another computer tonight.
 

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