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Background: The invasion of habitats by non-indigenous species (NIS) occurs at a global scale and can generate significant ecological, evolutionary, economic and social consequences. Estuarine and coastal ecosystems are particularly vulnerable to pollution from numerous sources due to years of human-induced degradation and shipping. Pollution is considered as a class of disturbance with anthropogenic roots and recent studies have concluded that high frequencies of disturbance may facilitate invasions by increasing the availability of resources. Methodology/Principal Findings: To examine the effects of heavy metal pollution as disturbance in shaping patterns of exotic versus native diversity in marine fouling communities we exposed fouling communities to different concentrations of copper in one temperate (Virginia) and one tropical (Panama) region. Diversity was categorized as total, native and nonindigenous and we also incorporated taxonomic and functional richness. Our findings indicate that total fouling diversity decreased with increasing copper pollution, whether taxonomic or functional diversity is considered. Both native and nonindigenous richness decreased with increasing copper concentrations at the tropical site whereas at the temperate site, non-indigenous richness was too low to detect any effect. Conclusions/Significance: Non-indigenous richness decreased with increasing metal concentrations, contradicting previous investigations that evaluate the influence of heavy metal pollution on diversity and invasibility of fouling assemblages. These results provide first insights on how the invasive species pool in a certain region may play a key role in the disturbance vs. non-indigenous diversity relationship. [ABSTRACT FROM AUTHOR]

The US Navy operates a large number of ships, however, unlike most commercial vessels they typically spend long periods of time in port where they may become fouled. This study investigated the feasibility of applying light cleaning (grooming) to maintain four surfaces free from fouling. The test surfaces were an ablative copper antifouling (AF) coating, a silicone fouling release (FR) coating, a two part marine epoxy, and a solid sheet of polytetrafluoroethylene plastic. The surfaces were exposed to static immersion in seawater on the East coast of Florida for 120 days and subjected to 3, 6, 12, and 24-day grooming intervals. Pre-groomed and post-groomed fouling conditions on each test surface were assessed and the maximum required lateral forces at each grooming event were measured. The results showed that grooming prevented or reduced the development of biofilm on the ablative copper coatings. The FR coatings that were groomed at the 3- and 6-day interval remained free from fouling until exposure to severe fouling pressure, which caused the 6-day interval to develop a small amount of fouling. Both the polytetrafluoroethylene and epoxy surfaces became fouled at all grooming frequencies, but fouling was reduced for the 3-day grooming frequency. The lateral forces required to groom the surfaces, with the exception of the FR coatings, increased with time. The results demonstrated that frequent grooming can have prolonged, positive effects on the AF performance of coatings. [ABSTRACT FROM AUTHOR]

Investigates the recruitment of sessile marine invertebrates on Hawaiian macrophytes. Question of whether pre-settlement or post-settlement processes keep plants free from fouling; Explanations for the lack of fouling on macroalgae and seagrasses; Types of anti-fouling protection.

Summary1. We conducted survey and transplant studies to determine whether colonization and residency on soft sediments by introduced, fouling mussels (Dreissena polymorpha and D. bugensis) were affected by physical disturbance, and whether Dreissena presence in turn influenced the diversity and population densities of other benthic invertebrates. Surveys revealed that colony density was typically higher at moderate depths than at shallower and greater ones. However, the largest, midsummer colonies and greatest coverage of sediments by mussels occurred at deeper sites. 2. Disturbance of transplanted colonies varied by depth and colony size, with deeper and larger colonies experiencing the lowest destruction rates. Colony destruction rate was positively correlated with current velocity adjacent to the lakebed. 3. Absence of mussel colonies at shallow sites was not determined by recruitment or substrate limitation, as recruit density was higher and sediment characteristics more suitable for postveliger settlement at shallow than at deeper sites. Rather, seasonal storms have much stronger effects in shallow than in deep water. 4. Mussel residency on soft sediment has profound effects on invertebrate biodiversity. Invertebrate species (taxon) richness and total abundance were positively correlated with mussel colony area. Mussel-sediment habitat supported between 462 and 703% more taxa, and between 202 and 335% more individuals (exclusive of Dreissena) than adjacent soft-sediment lacking mussels. 5. Results from this study illustrate that physical disturbance directly limits the distribution of mussels on soft sediments, and the diversity and abundance of other benthic invertebrates in consequence. [ABSTRACT FROM AUTHOR]

Reports that owners of pleasure boats may be unable to paint their vessels with antifouling agents containing tributyltin (TBT), as a result of legislation and regulation. Design of antifouling paints to keep organisms such as barnacles from settling on boat bottoms; Observation that leaching of TBT from the paint can harm aquatic organisms; Sensitivity of mollusks to TBT; Review of TBT by the U.S. Environmental Protection Agency (EPA) under the Federal Insecticide, Fungicide, and Rodenticide Act.