No other marine fish have been as instrumental in the growth of the marine hobby as the clownfish, particularly the ocellaris or false percula clown (Amphiprion ocellaris). Several species of clownfish have been kept and bred in captivity for several decades now.
Besides being relatively inexpensive and plentiful, clownfish are ideally suited for the majority of small marine aquariums. With the growing popularity of nano-reefs, clownfish are gaining even more favor among aquarists searching for small, peaceful fish. Wild clownfish are completely dependent on a host anemone for protection, so they do not have a large territory, making them ideally suited to the confines of an aquarium.
Unfortunately, there are a number of problems associated with the capture of these animals from the wild. It is ironic that the group of fish that caused many aquarists to try their hand marine fishkeeping has suffered extensively from their own appeal. In essence, its own popularity has been its undoing.
In conjunction with coral reef destruction caused by global warming and other events, the capture of clownfish for the marine aquarium hobby is severely depleting the numbers of wild clownfish. It is painfully clear that an alternative to collecting wild clownfish is desperately needed.
There is good news when it comes to clownfish. Due to the efforts of a number of intrepid aquarists and commercially operated ornamental fish farms, a steady supply of quality captive-bred (CB) clownfish are available. There are numerous advantages to CB clownfish over wild-caught (WC) clownfish. CB varieties are parasite-free, younger, already accustomed to aquarium foods and create no negative impact on the environment.
Captive-bred clownfish have not been through the stress of capture and the excruciatingly long process from the time it is collected to the time it is sold. In many instances, it may take a week or more from the time a clownfish is taken off a reef until it arrives at your local retail store. Considering the rigors that clownfish endure on the way to the store, it’s amazing any survive at all. Mortality rates both in shipping and in fish store tanks can be significant.
With CB clownfish, on the other hand, shipping is often less than a day of travel from the time they leave the breeder’s facility to when they are in a store’s tanks. The combined factors of short transit time, disease-free animals and careful handling results in hardly any fish loss at all — good for the fish, retailer and consumer.
One of the noted benefits of CB clownfish is the guaranteed age of the fish you are purchasing. Due to the social structure of clownfish, it’s impossible to know the age of a fish simply based upon size. In clownfish society, only the two largest, most aggressive fish are reproductively active. The rest of the individuals in the social group are forced to remain small and sexually inactive. For this reason, size is not a good indicator of age — a 10-year-old clownfish in the wild could the be the same size as an 8-month-old captive-raised fish, for example. Captive-bred clowns are often sold at between 6 and 12 months of age. Buying young fish means lower costs, greater adaptability and improved breeding success. Some breeders report that the young of CB clownfish are easier to raise than those from WC parents. As already noted, CB clowns are already accustomed to eating prepared aquarium foods, such as flakes, pellets and frozen diets.
One of the other benefits of purchasing CB clownfish is the knowledge that in doing so, you have done no damage to already fragile reef ecosystems. When a clownfish is removed from its host anemone, not only does that anemone frequently fall victim to predation, but the numerous species dependent on that anemone die, as well.
Purchasing CB clownfish also sends the message to retailers that we want CB fish. By letting the pet fish industry know that consumers will buy CB species, we can help prevent the destruction of the world’s reefs.
CB Clown Misperceptions
There are several myths regarding CB clownfish. Among the more persistent myths are that CB clownfish will not occupy host anemones and that these clownfish are inbred, resulting in facial deformities and missing stripes.
The desire to occupy a host anemone is a very strong instinct for anemonefish. This genetic trait doesn’t simply disappear within just one or two generations of breeding. In the wild, an anemone host is crucial to the survival of a clownfish, and CB clownfish prove just as eager for a host anemone.
I acquired a rather old breeding pair of CB clownfish that had never even seen an anemone. Within about 30 minutes of placing a bubble anemone (Entacmaea quadricolor) in their tank, they had taken up residence in their new host. Of course, my results may be atypical, as E. quadricolor is not a natural host species for A. ocellaris, so some individuals may take longer to acclimate.
Actually, it’s not all that essential to keep an anemone with clownfish in an aquarium. The proper clownfish aquarium will not contain any predacious fish, and therefore the need for a stinging host is completely unnecessary. However, because clownfish are generally poor swimmers, they will naturally seek a safe haven. Shelter for these curious fish can come in many forms, including bottles, filter intake tubes or even a laboratory beaker. Clownfish are resourceful and will frequently make the best of the situation.
The issue regarding inbreeding resulting in deformities requires more detailed explanation. It is true that deformities and genetic anomalies are more frequently seen in CB clownfish than in WC ones. The reason for this is quite fundamental. It is estimated that fewer than 20 of every million clownfish born in the wild survive long enough to reach breeding age. In captive aquariums, however, it is not uncommon for nearly 95 percent of the fish to survive to adulthood, despite deformities and genetic anomalies, making it possible for more genetic aberrations to be observed.
In addition, other factors, such as water parameters and nutrition during larval stages can greatly affect the quality of fish. Elevated nitrogen compounds in the water during larval stages have been shown to result in fish with gill flaring, or one or more incomplete or missing stripes. It is the responsibility of the breeder to cull deformed and otherwise undesirable fish.
Unfortunately, due to other issues — be it a desire for more profits or an inability to bring themselves to destroy fish — many breeders fail to remove these fish. Of course, a missing stripe or “bulldog” face does not mean there is anything genetically wrong, and these individuals can still prove to be wonderful additions to an aquarium (with any resulting progeny containing the genetic potential to be normal).
The fact that some people find these deformities appealing has led to the rise of certain “designer” clownfish. The problem is that by allowing these fish into the marketplace without the necessary explanation regarding their deformities, some breeders have made it possible for the negative image of CB clownfish to be perpetuated, continuing the myth. The fact is that inbreeding is not the cause of mis-barring and fish with missing vertebrae or jaw deformities (called “pug-nosed”). Jaw deformities can be caused by a simple birth defects or by water conditions during metamorphosis; these are not necessarily traits that will be passed along.
In most instances, the CB clownfish offered on the market are either F1 individuals (born of WC parents) or are F2 (born of F1 parents). In both cases, this is not nearly enough captive breeding to see any effects of inbreeding. Interestingly enough, due to the short larval period of clownfish, most wild populations of these fish probably represent pockets of genetically isolated fish. So, if anything, the CB clownfish offered for sale could most likely be termed “intraspecific hybrids,” which means fish born of parental species that simply have different geographical lineages. To a degree, this could be called hybrid vigor. Generally the term “hybrid” refers to breeding two different species, and it is generally accepted that when two different genetic lineages or species cross, the progeny end up with a good genetic mix and the strongest genes of both parents. In our instance, the mixed lineages are simply healthy fish of the same species with unrelated parents.
Demand Quality Captive-Bred Clownfish
As aquarists, the only way that we can justify the continuation of our hobby is through responsible fishkeeping practices, which include buying CB fish when available. If we continue to harvest at an ever-accelerating rate from the oceans, we will eventually run out of resources. With the technological advancements today in the areas of biology and aquaculture, it is clear that eco-friendly fish farming is both possible and essential.
As marine aquarium hobbyists, we can help this change happen by supporting aquaculturists who produce quality fish. Although the number of CB marine species nowhere rivals the quantities of aquacultured freshwater fish available (about 80 percent), the number is slowly increasing. One of the major roadblocks along the way is the limited funding available. Until aquarists begin supporting breeders by purchasing CB fish, the situation will be slow to change. In the case of clownfish, to date more than 13 species (from both Amphiprion and Premnas) are regularly cultured and offered for sale.
Want to Learn More?
The next time you find yourself at your local fish store, take a look at the tanks and ask the manager where his or her clownfish are coming from. Any good store dealing in saltwater fish can easily get CB clownfish for you at very competitive prices. Or why not try your hand at breeding clownfish? There is a wealth of information available on the subject, and it can be a very rewarding experience. Paying a few extra dollars is well worth the added expense to ensure a viable future for our hobby.