[Octopus]: Kobe - Abdopus aculeatus

[DWhatley]

You can expect to see a white "thread" growing from the tip. The first time I saw this on a newly acclimated animal I wondered if it was dead material that should be removed and might cause the new arm not to grow. Fortunately, I let nature take its course, the "thread" grew visible suckers, thickened and caught up with the other arms.

 

[Dools]

Kobe is as active as ever. At 86 days today, he is now my 2nd longest-lived octo and the longest-lived in this tank. I am including a few vids. In the first you can see new tips growing on a few of his arms. The other two vids are taken from above, I apologize for the lack of light. I was trying to show how he constantly raises his eyes and part of his mantle above the water surface. You can also see his "stump" in several of the vids.

 

[Dools]

I forgot to tell the new growth story. About a month ago, Kobe lost about an inch of one of his arms on the wavemaker that I had subsequently covered with the mesh from a net. I am still upset with myself for not learning from this incident and covering the other one. I wanted to share an observation from that incident and wonder if anyone has a similar story. I went to check on Kobe not too long after he had lost the tip of that arm. At the time he was on the glass and had the injured arm cradled in the center of his webbing very close to where his mouth is located. It appeared as if he was "sucking on his owey"; which made me feel even worse. Of course I am pretty sure that was not the case, but has anyone else see similar behavior? But as you may be able to see from the vid, it is growing back nicely. I hope to see growth from his "stump" soon too.

 

[DWhatley]

Octopuses have been known to eat parts of their own arms, sometimes to excess. The term, autophagy applies to this behavior. In some cases it appears to be caused by a bacteria, others stress and other in skin damage (personal observation, Octane). If you know the arm was damaged in the impeller, it may have damaged remaining skin that he chewed off. The bacterial cause is likely fatal (as was the excessive skin damage suffered by Octane from sitting under a fan during a tank escape) but stress (and likely minor damage) related causes appear to be recoverable. The observations are unclear but often with this species and I had wondered about all the tips being newly severed (ie no new grow showing) in your original pictures. Observing how long before you see the new growth in the recently dropped arm should give a hint as to how long before he arrived that the original tips were removed (either by self biting or having been lost looking for food).

 

[Dools]

He had new growth on two of his arms before the first impeller incident. It was probably 2 -3 weeks before I noticed the new growth on that arm. So he now has tips growing on 3 arms. I'll try and post a picture showing them, but he does like to keep moving and when he sleeps on the glass; he usually curls up in a ball.

 

[DWhatley]

This species is probably the most difficult to photograph with stills as it never seems to stop moving when it is not sleeping.

 

[Dools]

Agreed, I was going to take a still as he was motionless for a moment, but thought I could do a better job with a vid. Of course he was only still for that moment and just as I started recording he went into motion. Hopefully, you can see the older "new" tips on the arms on the camera's right side just before he slips away.

 

[Dools]

Attached is another vid focusing on Kobe's new growth on 3 of his arms. It is not great D, but hopefully you can see the new tips better.

 

[DWhatley]

My HD buffering is giving me fits so I get a lot of start stop but what I did see well was two of the stages mentioned in the arm regeneration article. On the tip that he lost entering the tank, I think the sucker slide down to the tip is still present where the other tips with the new "string" shows them realigned normally. I sort of noticed this on some of mine but did not know it was expected until I read the article. His third arm, I noted, is kept well protected

 

[Dools]

Thanks for the insights D. You are right regarding his 3rd arm; he does keep it curled. I have rarely seen it uncurled and then only momentarily. I am a little concerned because he has only nibbled on his shrimp chunks for the past few days. As you can see in the vids, he continues to remain very active and is out everyday. I will post any new developments.

 

[DWhatley]

I have extremely little experience with this species but with some of the others as they age they get bored with the food and offering something different may stimulate the declining, aging appetite. The latest thing I have tried with success (O. briareus) was a small piece of raw salmon (a blue crab claw, slightly cracked may also be tempting as this is normal fare for my larger animals -- only cracked when they are aging). The meat market guy looked at me strangely when I only wanted a small piece . I was in an Asian market so many of the employees have limited English and I only speak American (but can understand most Brit ) so I don't think I made it clear that the small piece I needed was for an octopus (of course, even if he did understand, that would not have removed the strange look ). It freezes well and can be cut frozen, thawing only what you plan to offer.

 

[Dools]

As always thanks for the advice. I will give it a day and try feeding him again on Tuesday. If that doesn't work, then it is on to the fish market, .

 

[Dools]

Kobe has passed the 90-day mark, but I fear the end may be near. He finally did eat some of the shrimp I offered him, but not nearly as much as he had eaten only a week ago. I've noticed his movements are often "jerky" and I tried to capture some that in the vid I am posting. I also notice he seems to stand on his arms often when he is on the sand bottom. D, is this also a sign of senescence? He also seems to expose more of his body and arms out of the water when he is dancing on the glass. I hope my assumption is wrong, but I do not think so.

 

[DWhatley]

I have not directly observed but one aculeatus and that animal came to me almost at the end of its life as one of our members was moving and could not rehome it locally. So, here is my best guess based on what I have seen in wild videos and on the journals. The good news is the "walking" is something observed in the wild and quite normal. When we first started seeing this species for home keepers, it was suggested we would never see this tractor like form of walking in the aquarium but larger tanks and more animals to observe has negated this thinking. However, the bad news (again conjecture) is that, at least in the video, Kobe's color looks grey and splotchy, something I have noticed on almost all my other senescent animals. I could only observe the mantle for a few seconds so I rewatched and then compared it to the prior videos to confirm (this could be an artifact of the lighting). Adding that to the amount of time you have had him and the slow down in accepting food does suggest you are in senescence. Sadly, this species seems to have a short senescent period where some of the more robust animals may take weeks to slowly decline. This may be more because keepers don't see the signs than actual rapid decline. I am not sure which is worse for the keeper. O. briareus often lives a month in a continually weakening state and the muscle loss is clearly visible (if the animal comes out of its den). O. hummelincki also seems to die more slowly. The muscle loss does not seem to be as apparent but the male becomes quite listless and grey.

 

[Dools]

Thanks for the info and your observations D. For the most part his color seems normal, but at times it is as you observed. In addition to his diminished appetite, the most significant change it he seems to sleep more during his usual waking hours. It seems the last week or so when I come home in the evening he has been sleeping in the front top corner of the tank for hour or two before he dances on the glass for awhile. Along with standing on the bottom more often, my other observation is when he is moving across the tank more of his arms and mantle are breaking the surface of the water. Not sure if that is due to him entering senescence or me being hyper-vigilant of his behavior.