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How do we know if captive cephs are happy?

Nov 5, 2014
Just for the record i never thought that my argument was probable, I just wanted to show her that my argument was just as valid as hers (both being unprovable).

Of course I know that we can never truly know what the animal feels, and their behavior we can only study to give us an idea of what it may be feeling based on other observations. I never said that animal behavior was an exact science. Regardless I still believe that we can have an idea of how an animal is feeling based on various indicators. If we never had any idea ever of what an animal may be feeling then animal behavior wouldn't be studied as it never would give any predictions better than random. This is how I base my argument, that we have behavioralists that can make predictions with a better than random chance of it being correct based on other observations. This is how I say we can "know" (read: very educated estimate) what an animal may be feeling.

Sorry, but if you agree that both arguments are unprovable...then you really can't justify keeping the animal captive, so be default I'd say that your friend is correct.

And I'm not sure how to stress this any more...behavioural scientist is not a synonym for animal psychiatrist. We observe behaviour, and try to understand the external factors influencing said behaviour. We may also try to understand how these behaviours relate to social interactions, predator/prey interactions, etc. No reputable scientific behaviour article will have a conclusion saying "therefore, the animal feels...". We may say "when the octopus is threatened, it will ink" but not "when the octopus is afraid, it will ink".

I quite agree with James that the question in keeping a captive animal is if it is being done ethically. Also, make sure you know the source of where your little octo-friend is coming from. I'm not really a fan of the aquarium trade..but there are some sources which are better than others. Also, Thales is very correct in saying animal ethics is "crazy town". When I do an ethics application for research...I have to write up a huge report saying exactly how I will keep/house/feed/transport/monitor/tell if they are sick/how to euthanise them if necessary/how many per tank and so, so much more. Then it goes off to a board who reviews it and sends back suggestions of what to change with an approval or disapproval. As a hobbyist, you don't have that...so do your research and have everything right...then if you're lucky, you might just end up with a "happy" octopus.


Staff member
May 30, 2000
From my signature but worth repeating here: Please Read First: TONMO.com Forum Guidelines and Cephalopod Care Ethics Statement
Also, make sure you know the source of where your little octo-friend is coming from.
This point (and more) is explored in this classic thread.

Lastly, this truly classic thread from 2003 produced this important statement by me:
I feel that bad things should really stop happening, and good things should continue happening. In fact, perhaps activity in good things should even increase, but I also would defer to any future research in this area.
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Dec 7, 2008
This is one of those topics, like politics or religions that's hard to have calm, rational discussion with a lot of people about. I agree with most of what's been said above thread already, but I'd add that this comes up in almost all "pet industries." I was heavily involved in the reptile/amphibian breeder community for many, many years and my opinions about keeping animals in captivity have certainly changed and become more...nuanced. It's really hard to draw lines in the sand. Many hobbyists I know have higher success rates at breeding animals than some zoos, and I used to be completely pro-captivity. Especially in the reptile world, there's a sentiment that it's a personal freedom thing, and they have an attitude of almost NRA-like activism about it. "Don't take my 20 foot burmese python away!" You also have PETA-style individuals who don't believe anyone should have any pets at all.
I heartily disagree with that. My problem with this, even discounting the ethics of animal "happiness" is that for some animals, captivity may be their last shot. I own three axolotl salamanders, for example, which are essentially extinct in the wild because of habitat loss, introduced fish, diseases and pollution. However, since axolotls are popular in the pet/breeder world and the scientific laboratory world, they live on, albeit in a heavily modified, captive form. Not saying this is always a justification, in fact, it's not--but captivity as "arks" for endangered animals is certainly an argument for captivity. Where it all falls apart for me is the pet trade itself. Going back to reptiles: it's really a global evil. Animals are harvested from the wild with pretty much no concern for anything. I stopped buying "wild caught" animals many years ago, but I'm probably an outlier. I know the aquarium industry can be pretty bad, but in the time since I left the aquarium hobby (around 2004) to now, I see a lot more emphasis on sustainable practices than I do in the reptile industry. There are many more tank raised options. Even cuttlefish can be tank raised. You don't have to use live rock plucked from the ocean.
I know I went a bit off topic there, but what I mean to say is, that while anti-captivity people have good arguments, there are also good arguments for keeping certain animals in captivity.


Feb 9, 2008
Tell your friend that theres many indicators (vitals, blood work, etc.) that make us look ok. but heck I still can be depressed doing the rat race of life. It's just the way it is lol No seriously, I think we can tell if an Octopus is distressed or not, and I don't think (as smart as they are) they have any of those useless byproduct of higher intelligence traits such as "unenvironmental depression, lack of "fulfillment" etc. If they play with you, greet you, eat, live months (or years if you're lucky to get yougin...and they aren't an endangered species....no worries for owning and caring for them. But ultimately...no one can be 100% certain ANY lifeform is "100% happy", us humans included.