Help with cause of death


Staff member
Moderator (Staff)
Sep 4, 2006
Cape Coral, FL
This one is difficult to write:sad:

Trapper, my unknown Atlantic octo is still apparently doing fine but has stayed recluse and I still am not sure what he is eating. My dwarf, however is either dead or will be by morning.

My dwarf (joubini/mercatoris) arrived a week ago. Thursday morning he was out and I got my first full look at him since acclimation. One eye was double the size of the other and he was having difficulty with balance. I had put in a new shell (it has been in my LR tank for months and in an aquarium before that) the day before. He was coming out of the shell and was having difficulty. There was something in his arm that I assumed was his supper. Once he extracted himself and the remains he just kind of fell over.

At that time I tried to think what could cause a swelling and I checked the salinity (I have been checking water parms daily) and that is when I realized I had not increased it to 1.026 as I had intended so it has been at 1.022 for a week. At 5:00 AM I wasn't thinking my best and increased the salinity rapidly. Later in the day, the eye appeared to be shrinking some but eventually the swollen area turned a dark brown, reminiscent of hemorrhaging. There was also a similar dark brown (not the typical redish brown) mark on one leg. He became totaly lethargic and eventually the shrimp started to pick at him so I put him in an isolation net. Throughout the day he became less and less responsive and I thought he was dead several times. Currently he does not move but is still reacting to light with some color changing in the head area much like a heart beat.

Can anyone tell me if the eye swelling and low salininty are related?
Would increasing the salt that rapidly have made any difference and could it have caused internal bleeding?
Is there another suggestion as to what would cause the symptoms?
Is the color change plausible after death?

Thanks for any help offered. I would like to try another dwarf but want to avoid this situation again if salinity issues do not fit the situation.
So sorry for you loss. I have seen octopuses continue to color change right up until death. My thinking is, being he was a dwarf, he could have been at the end of his life. I am not sure on the salinity issue but I'm sure someone else will have input.

I have seen them color change after death and also twitching of the arms.I have seen this twice if the color changing is in pulse's it is possible he is already gone and just nerves if this is the case i am sorry for your lose :sad:
Thanks Carol and DuchCourage, I considered ageing (especially with the loss of balance) but the eye swelling (which no one else has reported) and what I will call hemorrhaging make me think something unnatural happened to him.

It is 1:30 in the afternoon on friday and he continues to show a pulsing color change on parts of his body but there is no eye or leg movement. I keep hoping Steve or Roy will give some input since they have seen a lot of different situations in the lab.
Just free associating on things in your post, I could imagine that the salinity issue caused an osmotic imbalance that broke down some part of the circulatory system or similar, causing hemorrhaging. But this seems unlikely for a few reasons, the main one being that the salinity doesn't seem all that far off. I don't know where these guys live, but I'm sure tidepool octos are fairly robust with respect to salinity since they have to endure freshwater like rain reducing the salinity and evaporation increasing it.
That IS where I was going with my thinking (including the rethink on habitat but is why I thought to check the salt). I am wondering now if something else could have damaged the eye but it would seem it would have to have caused a lot of pressure and I can't think of anything in the tank that could have done that. The only live things in the tank are a mithrax, some snails, a pencil urchin and a lettuce slug. The rock is attached to an egg crate grid except for two loose pieces in the front. I have a hang on canister that is attached to an under gravel so the intake is not exposed at all and the return is through a length of PVC tubing with multiple holes like a spray bar but placed vertically.

Poor little guy still shows some signs of being alive. I have him in a plastic coffee can with an air stone for circulation and have been changing his water several times a day. He seems to be sluffing off the outer layer of skin and there is odor. The color changes have stopped and I can't see the little pulse in his head but he will move an arm tip from time to time. I know there is no hope but I check on him every hour or so anyway.

Thanks for mulling it over.
If your little guy smells, then he is gone :sad: . The skin coming off is another sign that he/she is gone. The muscles and nerves in the tentacles can respond to stimulus after death (a severed tentacle will still move and change color). Sorry for your loss.

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