Prince Edward County, Ontario, Canada
HANDLING THE FOUL AND THE LOATHSOME August/September, 2011 issue The bizarre object we were now staring at in the water was a cluster of Bryozoan, and it floated, half submerged, held in place by a sunken branch to which it appeared tethered. It was a something my fellow hikers had never seen before, and the “thing” fascinated them. I had encountered these strange objects before in slow moving bodies of water, interestingly, here at Depot Lakes Conservation Area more than anywhere else. “Is it a plant, or is it an animal?” they wanted to know. Bryozoan are actually animals, although millions of these microscopic aquatic organisms may have been involved in the baseball sized gelatinous mass that nodded in the water before us as if acknowledging our presence. It was only one of numerous features we found that day during our nine kilometre walk in this conservation area, just northwest of the village of Verona. At 3,000 acres, Depot Lakes Conservation Area is the largest of the some 30 conservation areas owned by Quinte Conservation. Its three lakes – Second, Third and Fourth Depot Lakes, make up the headwaters of the Napanee River. The Depot Lakes are part of a chain of five Depot Lakes in the area, but those within the conservation area itself are of particular importance as they serve as reservoirs, its two dams holding back volumes of water, and releasing it as needed to supply water downstream during periods of low flow. It was the size of a basketball, round and translucent, somewhat textured, but so slimy as to defy touching. Finally, it was I who volunteered to close my eyes and gently lift the object from the water for a closer look. As a dairy farmer from way back, my hands had already experienced many questionable textures, and had probed numerous dark recesses where most hands seldom venture. The gelatinous object I now held in my hand was attached to a decaying piece of vegetation and trembled noticeably as I rotated it for some clue as to what it might be. The sensation was not unlike holding a quivering ball of Jell-O, the only difference being, that it was decidedly sticky and certainly, not in the least bit appetizing. The Bryozoans that turn up at this time of the year are mostly the soft and gelatinous variety, but they do occur as tufted leaf-like fronds or even hard calcified skeletons, not unlike coral. Almost all Bryozoans are colonial, composed of anywhere from a few to millions of individuals. The one I held in my hand likely contained millions of individuals, all amassed to form the globulus gel I pulled out of the water. Although an animal they don’t really move around, although some species do to a certain degree. How do they reproduce? Bryozoans are able to propagate both sexually and asexually, the latter occurring by budding off new zooids (individual functioning units) as the colony grows. If a piece of the colony breaks off, this piece can continue to grow and form a new colony. Most are hermaphroditic - that is, individuals possessing both ovaries and testes. Some shed both eggs and sperm into the water where they fuse, but the majority brood their eggs in tiny chambers, capturing free-swimming sperm with their tentacles to fertilize the eggs. The eggs divide, develop into free-swimming larvae, escape from the brood chamber, and swim away to settle on an object somewhere to metamorphose into a new zooid, thus starting a new colony. Of course, we can’t see this unless we were to somehow view the whole process under a microscope. All we get to see is the mass of millions that have united to form something we can observe floating in the water - or hold in our hand, for those who dare to experience the sensation. At first glance, Bryozoans superficially appear to have more in common with coral, but Bryozoans and corals belong to quite different phyla and are unrelated. A glob that we may find is actually a colony of zooids, not polyps as in corals. And each of these zooids has whorls of delicate feeding tentacles gently swaying in the water catching food. Bryozoans feed on minute organisms, including diatoms and other unicellular algae. In turn, they are fed upon by grazing organisms such as small fish and are subject to competition from algae. Who knows what daily routine in their lives we interrupt by lifting specimens out of the water. And these little critters have been around for awhile. They have a fossil record extending back some 500,000,000 years, to the upper Cambrian period. Identifying a mass as a Bryozoa (or plural Bryozoan since there are millions of them in one cluster) is enough for us. To identify the exact species would be a painstaking job as there are about 5,000 living species in the world. And in some cases, they can be downright nuisances as they often clog water intakes. Yet, they produce an incredible variety of chemical compounds, some of which may possibly find uses in modern medicine. As an example, one compound produced by a marine species of Bryozoa, the drug bryostatin 1, is currently under serious testing as an anti-cancer drug. If you want to be “one up”, these little - and sometimes, not so little - critters of shallow water, are scientifically known as Pectinatella magnifica. The next time you see one of these globs attached to an underwater plant or fallen tree branch, impress everyone with your new found knowledge of the foul and the loathsome. Then bravely reach in the water and hold one up in your cupped hands for all to see. You will undoubtedly experience a few squeamish expressions from onlookers. You will also need a few paper towels and lots of cleaner to rid your hands of the accumulated slippery mucus. Enjoy! “The Blob” can be found in Fourth Depot Lake. However, any body of slow moving water will usually yield a few Bryozoan at this time of the year. For more information on birding and nature and guided hikes, check out the NatureStuff website at www.naturestuff.net Terry Sprague lives in Prince Edward County and is self-employed as a professional interpretive naturalist.