The Tank-Raised Cuttlefish at BZA
The Difference (Once Again) between Tank-Raised and Captive Bred

A couple days ago we advertised a WYSIWYG tank-raised cuttlefish (Sepia spp.) for sale in Collector’s Choice. We were surprised to learn this animal generated so much discussion in blogs, forums and social media. After having a look at some of those discussions, we see a lot of the conversation focuses on the “tank-raised” label, and we wanted to take a few moments to give you some additional information and clear up any confusion regarding the term “tank-raised.” 

Tank-Raised is Not Captive Bred

The cuttlefish we sold was a tank-raised cuttlefish insofar as it was raised in our tanks to a salable size by our husbandry staff. It was not captive bred, nor did we attempt to imply it was captive bred. Those of you who are familiar with our current selection of animals know we regularly offer a variety of fishes as tank-raised animals. These animals, like this cuttlefish, are in a distinct category separate from the captive bred animals we offer.

What’s the difference between captive bred and tank-raised? As we’ve written before, a captive bred animal is bred in captivity and is the offspring of captive parents. A tank-raised animal is an animal collected from the wild as a post-larval or newly settled animal and raised to a salable size in captivity. Both animals have their place in the hobby, along with those animals that are collected as older animals.

When considering older animals, aquarists may find two offerings, although a distinction is rarely made. The two offerings are a “captive-conditioned” animal and an animal with no label beyond being “wild-collected.” A captive-conditioned animal is an animal that has had the opportunity to become conditioned to captive life before sale. A captive-conditioned fish, for example, should be eating a captive diet well and be more gregarious than an animal just recently imported. Of course there is a lot of variability depending on species and even individual animal.

Slightly Different Than Most of Our Tank-Raised Animals

Unlike many of the tank-raised animals we sell, this cuttlefish was not intentionally targeted for collection, and we do not carry tank-raised cuttlefishes as a regular item (we know of no good commercial supply of tank-raised cuttlefishes in North America at present). Instead, this cuttlefish made its way into our system as a “hitchhiker.” When we found it, we moved it to its own holding system and “raised” it for a few months in our system until it was a salable size. While this animal was not intentionally harvested for the aquarium trade as a post-larval or newly settled animal, at the time we offered it for sale, it possessed all of the advantages of our other tank-raised animals (e.g., eating a captive diet, socialized to aquarium life, etc.). That is why we labeled it as tank-raised.

Why Buy Tank-Raised?

One of the reasons we carry a category of animals labeled tank-raised is that this category of animals is (or should be) of particular interest to many aquarists. Beyond the fact tank-raised animals are, in general, hardier animals and less prone to a stress-inducing adjustment period, the argument can also be made they are one of the most sustainable segments of the marine aquarium trade. At the point when tank-raised animals are collected, the natural mortality secondary to predation and competition is extraordinarily high. In laymen’s terms, many of the animals collected at this stage were not going to survive in the wild. As such, taking animals at this stage in their lifecycle takes pressure off the older animals that have a much lower mortality and will become the breeders of the future.

Of course some aquarists may argue tank-raised animals are not sustainable enough and that the only truly sustainable marine aquarium animal is a captive bred animal. While we support and actively promote captive breeding, those of you who have been around the Zoo for a while know we also believe strongly that animals collected from sustainable marine aquarium fisheries are an excellent choice. Why? Because a sustainable fishery, especially in many developing island nations, provides one of the best paths to appropriate socio-economic development for fishers whose villages are just entering global markets.

The Best Aquarist is the Educated Aquarist

We are happy the sale of our little tank-raised cuttlefish generated so much discussion because here at Blue Zoo Aquatics we care deeply about education. The discussion surrounding this animal and its tank-raised label has given us the opportunity to engage with you, our readers and customers, about an important topic. We try to offer a variety of healthy and beautiful animals to our customers. While that variety comes in the form of many, many species, it also comes in the form of the types of animals we sell. Understanding the difference between captive bred and tank-raised animals will make you an even more educated aquarist, and we believe the educated aquarist is the best aquarist! Thanks for reading.