Most people are aware of the need to maintain wild places in as pristine a state as possible. In many situations, however, protection is not enough. Understanding is required, as many wild places are becoming increasingly cut off from the systems that support them, so much so that human intervention is required if they are to remain viable. Unfortunately, a thorough understanding of an environment is largely impossible when people know so little of the creatures that exist within it. As many aquatic creatures go about their lives largely out of the sight and reach of humans, careful observations of well-housed captive specimens may offer the most practical alternative.

Aquatic animals, especially those that live in small freshwater systems, are often affected by pollution more directly than are other animals. With rare exceptions (see “Walking Catfish,” at page 76), such creatures cannot leave their environments when conditions deteriorate. Furthermore, animals that live in water are constantly surrounded by and in touch with whatever pollutants are introduced into their environment. They not only live in the water, but also draw it into their bodies as part of their respiratory processes.

Fish and aquatic invertebrates are, in effect, “canaries in the coal mine,” in that many begin to suffer or disappear long before the destructive effects of human activities become obvious.

It is imperative that people learn as much as they can about the animals for which they are responsible. You should be sure that any animals you purchase have been captive bred. In addition to the ethical concerns involved with damaging an animal population, it is also worth noting that humans have much to learn from our fellow creatures. Nearly all of our medicines have come from natural sources, and no one can be sure where the next important disease cure will be found. The body chemistries of any number of fish, plants, or invertebrates may hold important keys to the future health of our own species. Each extinction closes the door to such possibilities.

Increasingly, international and local authorities are moving to protect aquatic animals by regulating or prohibiting their capture and sale. Unfortunately, the enforcement of such laws is spotty at best, especially because authorities are often overburdened and occupied with many other concerns.

It is up to each aquarist to be scrupulous in avoiding the purchase of protected fish and aquatic invertebrates while understanding that unscrupulous collectors and dealers are often able to circumvent governmental regulations. An offer of sale at a pet store or, especially, via mail or the Internet, is absolutely no guarantee that ownership of the animal is legal.