Fouling Community Composition Research Articles

Fouling community composition on a pilot floating solar-energy installation in the coastal Dutch North Sea

The increasing need for renewable energy has led to the transition of renewable energy devices to the marine environment. Currently, mainly offshore wind farms have been completely developed and are operational in the North Sea. The solar energy sector is also rapidly evolving and floating photovoltaics are continuously created and deployed. In this study, we investigated the colonisation patterns and community changes with time of fouling fauna on the first floating photovoltaics in the coastal Dutch North Sea. Samples were collected by divers from the underwater side of 4 floaters, coated with different anti-fouling techniques (Intersleek, GreenPowerNano PPDura, Finsulate and Pato) at two different moments, shortly after the deployment of the floaters and approximately a year later. In total, 72 fouling taxa were identified on the floaters, from which ca. 11% are known to be non-indigenous species for the region. The anti-fouling coating Intersleek seemed to work the most efficiently against fouling colonisation, since the fouling community sampled from this floater contained the least taxa. However, the small number of samples collected from the different floaters did not allow for a direct comparison between the anti-fouling coatings. The communities evolved with time, with young communities accommodating a larger number of individuals and old communities having less individuals but higher biomass, indicating that the organisms become bigger in size and compete for the available space. Nevertheless, the communities had not reached a stable climax yet, while this process might take multiple years due to the dynamic environment in which floating photovoltaics are deployed. Monitoring the fouling communities occurring on floating photovoltaics in the North Sea for a long-term is necessary to understand the effects of these new man-made structures on the marine environment, especially since floating photovoltaics are moving to offshore locations and will be possibly co-located with offshore wind farms in the future.

The Effect of Husbandry and Original Location on the Fouling of Transplanted Panels

The best way to stop the introduction of non-indigenous species (NISs) is by preventing their transport. In the case of ship hulls, this may be accomplished by managing entrainment onto the hull. This study was designed to examine the role of hull husbandry, i.e., cleaning and grooming, in fouling community structure and to determine the effect of husbandry on the recolonization of surfaces after a transplant was performed. A series of panels were placed at two locations along the east coast of Florida (Port Canaveral and Sebastian Inlet) that are typified by distinct fouling communities. Panels were subjected to one of three treatments: groomed weekly, cleaned every two months, or freely fouling. After four months, all panels were cleaned and transplanted between sites; no further husbandry was performed. Fouling community composition and coverage was characterized at monthly intervals both before and after transplantation. Hull husbandry was found to affect coverage and composition, with groomed panels carrying a lower cover of macrofouling in general. The effect of the original location on subsequent fouling composition and recolonization by specific organisms was confirmed for encrusting bryozoans, barnacles, sponges, and tunicates. Hull husbandry also affected subsequent fouling with specific preferences shown for surfaces that had been groomed, cleaned and undisturbed.

Differences in fouling community composition and space occupation across broad spatial and temporal scales

Sessile marine invertebrate (biofouling) communities have served as an important model in ecology for evaluating fundamental patterns and processes, including invasion dynamics, which vary at broad spatial and temporal scales. Here, we tested for differences in biofouling community development among three biogeographically distinct bays in North America (Chesapeake Bay, Tampa Bay, and San Francisco Bay), exploring possible explanations for differential non-native species success. In particular, we aimed to examine if San Francisco Bay (a global hotspot for non-native species richness) differed in composition and space occupation, especially since open space can facilitate colonization. Additionally, we explored how biogeography, assembly and succession dynamics over the short and long term, and space availability affect marine communities across broad spatial scales. Patterns of community assembly differed among bays, with more bare space and less secondary cover (species settling on species) in San Francisco Bay. San Francisco Bay was also distinguished by a higher percent cover of Tunicata (almost all of which are non-native and historically absent) over multiple time scales. Cirripedia recruited on bare panels in all three Bays but cover increased only in Tampa Bay, as soak time increased. Tube-dwelling Polychaeta distinguished Chesapeake Bay from Tampa Bay and San Francisco Bay. Low-salinity events temporarily restructured the communities in all three bays. Whether differences among bays reflect coastal versus bay-specific patterns remains to be tested.

Impacts of habitat and predation on epifaunal communities from seagrass beds and artificial structures

Within the coastal marine environment, the increased presence of artificial habitat can have negative impacts on the functioning of marine communities. Artificial structures provide a novel, hard surface for the colonization and growth of a variety of marine species and disproportionally favor introduced species. With the global rise in hardened shorelines, it is imperative to examine the ecological processes that occur within these habitats to those occurring in natural habitats. Here, we compared habitat differences in fouling community composition of different successional ages as well as the impact of predation on those communities. Specifically, we investigated how communities differed with respect to natural (seagrass beds) and artificial (docks) habitats and then exposed previously caged communities to predators to examine prey-specific effects within each habitat and on different aged communities. We found that habitat was a good predictor of community structure including both total species richness and introduced species richness higher in artificial habitats. We expected predators to increase available space allowing increased species co-existence, however, this was not the case. Predators in both habitats reduced richness despite having a strong impact on the percent cover of dominant groups. Predators also reduced introduced species richness, particularly in artificial habitats. Artificial structures are an important pathway of success for introduced species and results here show the importance of biotic resistance within these habitats, potentially limiting the spread of introduced species into natural habitat. Overall, species found within the different habitats could be predicted based on life history traits and predators did not increase the similarity of communities between habitats though still acted in a comparable way, reducing the dominant groups.

Fouling community characteristics in subtropical coastal waters of the southwestern East China Sea

A fouling study was conducted in coastal waters southwest of the East China Sea between December 2013 and November 2014. A total of 84 species of fouling organisms belonging to 69 genera, 49 families, and 10 phyla were recorded over the entire year. The community composition was dominated by coastal warm-water species belonging to typical subtropical inner bay communities. The prosperous stage of settlement lasted from April to September, and the adhesion strength of the fouling organisms was the highest in summer. Sessile suspension feeders constituted the main core of settlement for the fouling community. Amphibalanus reticulatus was the most dominant and representative species of fouling organism, and other dominant species included Caprella equilibra, Ectopleura crocea, Anthopleura nigrescens, Stylochus ijimai, Spirobranchus kraussii, Crassostrea angulata, Perna viridis, Jassa falcata, Stenothoe valida, Sphaerozius nitidus, and Biflustra grandicella. The individuals in the fouling community showed a mutual dependence or constraint relationship due to competition for settlement space and food, and they exhibited a particular spatiotemporal distribution in accordance with adaptation to environmental factors. Temperature was the most important environmental factor determining the geographic distribution of fouling organisms. The temperature characteristics of species essentially reflect the differences in the fouling community composition in various climate zones. The species number, settlement stage, and settlement rate of fouling organisms are closely related to water temperature. Local natural environmental conditions (salinity, water currents, light, etc.) as well as human activity (such as aquaculture production) are all important factors affecting the settlement of fouling organisms.

Influence of hydrodynamic stress on the frictional drag of biofouling communities

The role of hydrodynamic wall shear stresses on the development of the fouling community structure and resulting frictional drag were examined using a commercially available fouling release coating. Immersed test panels were exposed to three different hydrodynamic treatments, one static and two dynamic (corresponding to an estimated wall shear stress of 7.0 and 25.5 Pa). The drag of the panels was measured in a hydrodynamic test chamber at discrete time intervals over 35 days. The fouling community composition on the static panels was significantly different from the organisms observed on the dynamic panels. Despite different fouling community composition, the drag forces measured on the panels were very similar. This suggests that the frictional drag of low form and soft fouling communities are similar and that there may be a stepwise increase in frictional drag associated with the presence of mature calcareous organisms.

The ghost of fouling communities past: the effect of original community on subsequent recruitment

Biofouling on ships has been linked to the spread of invasive species, which has been identified as one of the current primary threats to the environment. Previous research on antifouling coatings suggested that the quantity of fouling, as well as community composition, on biocidal coatings was modified by prior fouling settlement. The experiment reported in this paper was designed to determine how preconditioning affected the rate and composition of subsequent fouling on transplanted silicone coatings. A series of 10 × 20 cm panels coated with Intersleek 700 or DC3140 were placed at three locations in Florida (Ponce Inlet, Sebastian Inlet, and Port of Miami), which were characterized by distinct fouling communities. Panels were immersed for four months, cleaned, and reciprocally transplanted among the three sites. Fouling community composition and coverage were characterized at bimonthly intervals both before and after transplantation. The original fouling community affected the subsequent fouling composition and recolonization by tunicates, sea anemones, barnacles, sponges, hydroids, and arborescent bryozoans. The community-level effects were short-term, lasting 2–4 months, but specific responses lasted up to 14 months post-transplant.

Effects of Eutrophication, Seasonality and Macrofouling on the Diversity of Bacterial Biofilms in Equatorial Coral Reefs

Biofilms play an important role as a settlement cue for invertebrate larvae and significantly contribute to the nutrient turnover in aquatic ecosystems. Nevertheless, little is known about how biofilm community structure generally responds to environmental changes. This study aimed to identify patterns of bacterial dynamics in coral reef biofilms in response to associated macrofouling community structure, microhabitat (exposed vs. sheltered), seasonality, and eutrophication. Settlement tiles were deployed at four reefs along a cross-shelf eutrophication gradient and were exchanged every 4 months over 20 months. The fouling community composition on the tiles was recorded and the bacterial community structure was assessed with the community fingerprinting technique Automated Ribosomal Intergenic Spacer Analysis (ARISA). Bacterial operational taxonomic unit (OTU) number was higher on exposed tiles, where the fouling community was homogenous and algae-dominated, than in sheltered habitats, which were occupied by a variety of filter feeders. Furthermore, OTU number was also highest in eutrophied near-shore reefs, while seasonal variations in community structure were most pronounced in the oligotrophic mid-shelf reef. In contrast, the macrofouling community structure did not change significantly with seasons. Changes in bacterial community patterns were mostly affected by microhabitat, seasonal and anthropogenically derived changes in nutrient availability, and to a lesser extent by changes in the macrofouling community structure. Path analysis revealed a complex interplay of various environmental and biological factors explaining the spatial and temporal variations in bacterial biofilm communities under natural conditions.

Marine fouling on floating installations west of Dongsha Islands, the northern South China Sea

Marine fouling on floating installations west of Dongsha Islands, the northern South China Sea, was investigated from August 1987 to October 1990. Two buoy stations were deployed at approximately 110 km and 115 km west of Dongshadao, Dongsha Islands, anchored in water at 325 and 345 m depths, and exposed for 8 and 12 months. The experimental panels were fixed on iron structure frames which were connected to the buoy and its mooring system immersed in water at different depths, and retrieved after 4, 8 and 12 months of exposure. Fouling organisms colonizing the buoys and their mooring systems were sampled after 8 and 12 months of deployment. A total of 86 species was collected and identified at these two stations and the fouling community showed a typical oceanic characteristics. Most of the species were mainly found in the top 50 m depth and a striking vertical zonation of species was also observed with depth. The distance from offshore is a major factor in determining the fouling community composition. In terms of biomass, the fouling community was dominated by pedunculate barnacles, hydroids, and algae, followed by common oysters, pearl oysters and acorn barnacles. Biomass of hard fouling organisms increased over time. Under the influence of hydrological currents propagules of communities around the Dongsha Islands may also affect the development of the fouling communities in the offshore waters.