Last updated over 4 years ago
The world’s ocean provides a variety of ecosystems for marine organisms depending on the depth of the water and the type of substrate found on the ocean floor. Most of the Gulf of Mexico’s seafloor and shores are soft, sandy bottoms which provide no surfaces for attachment of sessile (non-mobile) organisms. However, there are many artificial structures which provide hard surfaces to which sessile organism can attach. Any hard surface or substrate, such as wooden piers, pilings, concrete bulkheads, rope, jetties, navigational markers, boat/ship hulls, and even fishing line and other marine debris provide a suitable place for attachment by sessile organisms. Within a single day, slime layers of bacteria, protozoans, and diatoms can coat any submerged hard substrate. Chemicals produced by the living slime layer attract free-swimming larvae of sessile organisms. Animals such as mussels and barnacles intensively compete for space on structures such as buoys and hulls of ships. These organisms attract resident populations of mobile animals like crabs, seastars, worms, snails, and fishes. Finally, larger animals and fish congregate, seeking food, shelter, and protection. Once the climax community is established, it is referred to as “fouling.” Opportunistic and tenacious, but rich in diversity, fouling communities also create negative impacts for economic reasons. For recreational boaters, commercial fisherman, military vessels, and the merchant shipping industry, fouling communities create drag and extra weight; reducing cruising speeds and increasing fuel costs. Other expenses are incurred by having the vessels dry-docked, pressure-hosed, sanded, and repainted. The annual process can cost billions of dollars in maintenance. Still, these fouling communities are fascinating to observe and study, as they provide the opportunity to see a variety of organisms taking advantage of a hard substrate in a marine environment.