Pearls are not only a product of a living being—a mollusk—but their mother mollusk is also a host for dozens of other life forms! When we think about other animals that we use in our lives (as a food source or as a luxury good, such as furs), we can rarely imagine these creatures being a part of something larger or coexisting with other animals from different species. We may picture a hen house bursting with chickens or a pen full of cows, but we find it hard to imagine these caged animals as part of something greater, but with pearl oysters it is quite the opposite and quite fascinating.
In nature, pearl oysters are usually found attached to rocks or hard corals, thus they are surrounded by other life forms. The rocklike shells of pearl mollusks make them extremely attractive to many species of plants and animals that will call a pearl oyster home. I once handled pearl oysters that were literally covered with life—about five species of algae, six species of polychaete and flat worms, eight species of crabs and crustaceans, four types of snails (conchs, limpets, and chitons), and seven species of other mollusks (drill mussels, geoducks, mussels, scallops, and other pearl oysters). And these were the ones I could see just by using my eyes.
In a sense, pearl oysters resemble a small ecosystem of their own, a self-contained biome where an ecological tug of war ensues that leads to eventual stability. But why would this be important? We have two more articles to explore this subject, but it is important to say that sometimes we focus on the large item in the picture and miss out on all the other important images. One of my teachers once told me about a gray whale symposium he attended; the speaker mentioned the importance of saving gray whales when another man chimed in to explain that without gray whales, we would also lose a unique species of barnacle. For sure, we rarely see the whole environmental picture.
Image: (lt.) Pearl oysters teaming with sea life versus ones (rt.) that have been cleaned by sea urchins
Douglas McLaurin-Moreno is a biochemistry engineer with a master’s degree in sustainability and natural resources management as well as a university professor, PAO instrstructor, and a founder of the Sea of Cortez pearl brand, the first commercial marine pearl farm in the entire American continent. Image is Moreno's own.