It is a tough world out there - octopus cannibalism

[Neogonodactylus]

While there are several reports of cannibalism in octopus, we certainly don't see it very often. Yesterday I introduced a small male into the aquarium of a larger female Abdopus aculeatus expecting them to mate. He never had a chance. As soon as I released the male, the female jetted across the tank and totally enveloped him in her web. I immediately tried to break it up, but short of injuring her, there was nothing I could do. A couple of hours later she dropped his remains having eaten most of the arms.

Roy

 

[OB]

A harsh mistress...

 

[neurobadger]

Any indication as to what caused her to eat him rather than mate?

 

[SueAndHerZoo]

Wow, when she says no, she MEANS NO!

Not trying to make light of it, though.... it's very sad. So sorry this happened.
Sue

 

[Lmecher]

Wow, that's brutal

 

[DWhatley]

I am glad you posted this AFTER we put Cassy and Tank together. I am not sure I would have made the attempt had you posted it earlier.

I feel less silly now panicking when I thought Cassy was covering Tatanka instead of the other way around!

Do you think she attacked something that entered her tank rather than a male suitor? This was another concern when we put Cassy and Tatanka together and why we used a divider panel until she was calm. I am not sure that was helpful because in both matings the coupling was really, really fast. Once separated and he did not have a clear grip on her from above, the male scurried to the other side of the tank and I suspect it was a natural defense to escape predation (Cassy made no attempt to follow either time).

 

[SabrinaR]

I am glad you posted this AFTER we put Cassy and Tank together. I am not sure I would have made the attempt had you posted it earlier.

I feel less silly now panicking when I thought Cassy was covering Tatanka instead of the other way around!

Do you think she attacked something that entered her tank rather than a male suitor? This was another concern when we put Cassy and Tatanka together and why we used a divider panel until she was calm. I am not sure that was helpful because in both matings the coupling was really, really fast. Once separated and he did not have a clear grip on her from above, the male scurried to the other side of the tank and I suspect it was a natural defense to escape predation (Cassy made no attempt to follow either time).

Apparently you had every reason to be concerned. I mean just WOW! I dont blame you for being nervous. I would be a wreck!

 

[Neogonodactylus]

The female has been eating live grass shrimp and seems well fed. She is usually fairly slow to attack the shrimp, so the speed with which she approached and enveloped the male suggests that this was more than simple predation. We have mated her several times in the past month, so she probably doesn't need sperm.

Roy

 

[DWhatley]

Interesting. I wonder if you had put a fish in there if she would have acted the same way. It might suggest protective mode of her soon to be brooding environment. I have noticed at least two of my females (without fertile eggs) become protective of their soon to be brood area but not to the extent of eliminating the intruder. There is a short video of Maya casting out a starfish after she laid her eggs and they were gone but we saw her patroling the tank before brooding.

 

[skywindsurfer]

Would placing both animals into a new unfamiliar tank alleviate aggression?