by Monica Yasunaga,
Marine conservation student
Marine degradation from coastal pollution is difficult to measure without the appropriate frame of reference. The parameters that must be considered include the physical, chemical, and biological interactions that are taking part in an area. To understand the extent to which human-induced development and activities affect marine ecosystems, biologists can look to the bottom of the food chain for the meat of the story. Benthic invertebrates, namely those organisms inhabiting the seafloors, are vital to the rest of the food web. Unlike the popular macro invertebrates of the sea (i.e. octopi, squids, and sea jellies) benthic invertebrates are significantly smaller in size– from microscopic to just a few centimeters long (Figure 1 below). On the sea floor they inhabit the surface of rocks, vegetation, coral, and the tiny spaces between sedimentary deposits. These animals support entire food webs, provide ecological services by overturning sediment via burrowing, and are an integral part of aquatic nutrient exchange (Gray et al. 1990). Changes in benthic invertebrate biodiversity over time may be linked to marine pollution trends in coastal ecosystems.