However, even if you provide the best possible care for an octopus, Katherine Harmon Courage says they don't make good pets.
There are many options for enriching the environment in which your animal is housed, but providing an abundance of live prey periodically is one of the simplest and most satisfying for your animal. Even in locations where live crustaceans are not easily obtained (either as bait or from a seafood shop or Asian grocery), there are usually alternatives such as “feeder glass shrimp” available from pet shops that can provide a nutritious and stimulating treat for your animal. Other options are to periodically feed your octopus in a novel way such as using a bamboo skewer through a cork to feed fresh shrimp, or placing the food item in a plastic bottle with a drilled cork sealing it. Some animals will figure out these games very quickly and become bored with them again, whereas others may never figure them out and simply give up (Wood and Wood 1999). In any case, it is important for you to continue to come up with new ideas to challenge your pet, and a variety of aquarium safe (i.e., nometal!) toys (such as a ping-pong ball or some cat toys) for your pet to amuse themselves.
The reason that I encourage you to find a suitable alternative live prey to feed your octopus is simple. Aside from the nutritional issue, live prey has another benefit over fresh or frozen seafood: your octopus will have to hunt it. This may seem unimportant to you, but it turns out to be very important to your pet. As I mentioned above, these animals are extremely intelligent predators, and spending their life in a completely predictable and unchanging glass box is not only boring for them, it has a strong impact on both their health and behavior (e.g., Wood and Wood 1999). In fact, during his research with baby octopuses at Dalhousie University, James Wood discovered that he could prevent “suicides” (animals crawling out of their tanks and drying out) by adding sufficient numbers of toys and challenges to keep the animals interested (e.g., Wood and Wood 1999). Professional zookeepers have long recognized that captive animals housed in unnatural and unstimulating enclosures candevelop abnormal, repetitive and neurotic behaviors, and most zoos have made a serious effort to enrich the environment in which their animals are housed to avoid such behaviors (which has led to the development of a trade journal for zookeepers and professional aquarists titled The Shape of Enrichment to exchange ideas to better stimulate captive animals). Octopuses are no exception to this issue, and a captive animal housed in a tank without sufficient hiding places and without sufficient stimulation can develop a number of stress behaviors including white color patterns, inking, frequent deimatic displays (these are sometimes called “startle flashing” in which false eye spots or brilliant colors are suddenly displayed in an attempt to startle a potential predator), autophagy (eating the tips of their own arms), hiding all the time (depending on species, however, this may be natural in some particularly timid species), and rapid jetting into the side of the tank, amongothers (e.g., Wood and Wood 1999). It is therefore critical that you make every effort to try to provide sufficient stimulation to your pet in order to avoid such behaviors and prolong their life in captivity.
Do an AMA about having an octopus for a pet
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