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Eco-engineering for Climate Change—Floating to the Future

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Recent papers suggest that epifaunal organisms use artificial structures as stepping-stones to spread to areas that are too distant to reach in a single generation. With thousands of artificial structures present in the North Sea, we test the hypothesis that these structures are connected by water currents and act as an interconnected reef. Population genetic structure of the Blue mussel, Mytilus edulis was expected to follow a pattern predicted by a particle tracking model (PTM). Correlation between population genetic differentiation, based on microsatellite markers, and particle exchange was tested. Specimens of M. edulis were found at each location, although the PTM indicated that locations >85 km offshore were isolated from coastal sub-populations. Fixation coefficient FST correlated with the number of arrivals in the PTM. However, the number of effective migrants per generation as inferred from coalescent simulations did not show a strong correlation with the arriving particles. Isolation by distance analysis showed no increase in isolation with increasing distance and we did not find clear structure among the populations. The marine stepping-stone effect is obviously important for the distribution of M. edulis in the North Sea and it may influence ecologically comparable species in a similar way. In the absence of artificial shallow hard substrates, M. edulis would be unlikely to survive in offshore North Sea waters.
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Overfishing is a major environmental problem in the oceans. In addition to the direct loss of the exploited species, the very act of fishing, particularly with mobile bottom gear, destroys habitat and ultimately results in the loss of biodiversity. Furthermore, overfishing can create trophic cascades in marine communities that cause similar declines in species richness. These effects are compounded by indirect effects on habitat that occur through removal of ecological or ecosystem engineers. Mass removal of species that restructure the architecture of habitat and thus increase its complexity or influence the biogeochemistry of sediments could have devastating effects on local biodiversity and important water–sediment processes. The possible overexploitation of engineering species requires more attention because the consequences extend beyond their own decline to affect the rest of the ecosystem. This is particularly problematic in the deep ocean, where oil and gas exploration and fishing pressure are likely to increase.
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Owing to a combination of increase in coastal population and processes related to global climate change, intense coastal development is inevitable. Shallow-water habitats are prone to be replaced by structures such as seawalls and breakwaters. While adding ample hard substrate to the seascape, these structures are not surrogates to natural habitats, and are often associated with nuisance and invasive species. These differences are attributed to design features including high inclination, low complexity and high homogeneity - all atypical of natural habitats. To date, coastal infrastructure has been designed with limited consideration to marine life developing on it. Consequently, its ability to provide ecosystem services similar to those offered by natural habitats has been severely compromised. This paper presents two case studies implementing ecological enhancement at the Brooklyn Bride Park waterfront. Both strategies are examples for restoring viable ecosystem services while also serving structural and societal goals. The first is an example of structural repairs of aging pier piles, by applying innovative technology of ecological concrete encasement which creates valuable habitat. The second is an example of boosting the ecological performance of a constructed riprap waterfront, by integrating precast tide-pools that add water-retaining habitat features lacking from standard coastal infrastructure.
Article
Concrete based coastal and marine infrastructure (CMI) such as ports, piers, industrial facilities and coastal defense elements dominate coastal zones world-wide. Coastal hardening replaces natural habitats with urban/industrial waterfronts that cannot provide ecosystem services similar to those offered by undisturbed coastlines. As a result, CMI are often considered as sacrificed zones with no environmental value. Studies show that marine flora and fauna on CMI, is typically less diverse than natural assemblages, and is commonly dominated by nuisance and invasive species. Here we summarize the results of a 24 month monitoring study of a breakwater section (Haifa, Israel) composed of armor unites cast from a proprietary concrete mix with an ecological design (ECOncrete® Antifers – EA). The study compared benthic community structure (fish, invertebrates and algae), species richness, live cover, diversity and the ratio of invasive to local species, on EA to that of an adjacent breakwater section made of standard Antifers (SA) composed of Portland based concrete. The abundance, richness and diversity of invertebrates and fish were higher on and around the EA compared to SA, while the ratio of invasive to local species was considerably lower. Moreover, engineering species such as oysters, serpulid worms, bryozoans and coralline algae were more dominant on the EA than on the SA. These ecosystem engineers increase the complexity of the structure, by means of biogenic buildup, which increase the availability of food and shelter in the area, while potentially contributing to the structures stability and longevity via bioprotection. The study indicates the ability of design substrate alterations to facilitate competition for space between local and invasive species on CMI, and demonstrates the feasibility of applying environmentally sensitive technologies for enhancing the biological and ecological performance of structures like breakwaters, piers, and seawalls. Ecological enhancement of concrete based CMI increases the ecosystem services provided by the structure, without hampering its structural performance, and thus should be integrated into future coastal development projects, preferably and most efficiently from early planning stages.
Article
Coastal defences are proliferating in response to climate change, leading to the creation of more vertical substrata. Efforts are being made to mitigate their impacts and create novel habitats to promote biodiversity. Little is known about the effect of aspect (i.e. north-south directionality) and inclination on intertidal biodiversity in artificial habitats. Artificial and natural habitats were compared to assess the role of aspect and substratum inclination in determining patterns of biodiversity at two tidal heights (high and mid). We also compared grazing activity between north-and south-facing surfaces in natural habitats to examine the potential for differential grazing pressure to affect community structure and functioning. Results were variable but some clear patterns emerged. Inclination had no effect on biodiversity or abundance. There was a general trend towards greater taxon richness and abundance on north-facing than south-facing substrata in natural and artificial habitats. On natural shores, the abundance and grazing activity of 'southern' limpets (i.e. Patella depressa) was greater on south-facing than north-facing substrata, with possible implications for further range-expansion. These results highlight the importance of incorporating shaded habitats in the construction of artificial habitats. These habitats may represent an important refuge from grazing pressure and thermal and desiccation stress in a warming climate.
Article
Underwater cities have long been the subject of science fiction novels and movies, but the "urban sprawl" of artificial structures being developed in marine environments has widespread ecological consequences. The practice of combining ecological principles with the planning, design, and operation of marine artificial structures is gaining in popularity, and examples of successful engineering applications are accumulating. Here we use case studies to explore marine ecological engineering in practice, and introduce a conceptual framework for designing artificial structures with multiple functions. The rate of marine urbanization will almost certainly escalate as "aquatourism" drives the development of underwater accommodations. We show that current and future marine developments could be designed to reduce negative ecological impacts while promoting ecosystem services.
Chapter
Rapidly growing populations and expanding development are intensifying pressures on coastal ecosystems. Sea-level rise and other predicted effects of climate change are expected to exert even greater pressures on coastal ecosystems, exacerbating erosion, degrading habitat, and accelerating shoreline retreat. Historically, society’s responses to threats from erosion and shoreline retreat have relied on armoring and other engineered coastal defenses. Despite widespread use on all types of shorelines, information about the ecological impacts of shoreline armoring is quite limited. Here we summarize existing knowledge on the effects of armoring structures on the biodiversity, productivity, structure, and function of coastal ecosystems.
Article
As well as their destructive roles, plants, animals and microorganisms contribute to geomorphology and ecology via direct and indirect bioprotection, which can reduce weathering and erosion. For example, indirect bioprotection can operate via biotic influences on microclimate whereby physical decay processes associated with fluctuations in temperature and moisture (salt crystallization, thermal fatigue and wetting-drying), are limited. In the intertidal zone, the spatial and temporal distribution of macroalgae (seaweeds) is patchy, related to physical and ecological conditions for colonization and growth, and the nature and frequency of natural and anthropogenic disturbance. We examined the influence of seaweed canopies (Fucus spp.) on near-surface microclimate and, by implication, on conditions for mechanical rock decay and under-canopy ecology. Monitoring on hard artificial coastal structures in South West England, UK, built from limestone and concrete showed that both the range and maxima of daily summertime temperatures were significantly lower, by an average of 56% and 25%, respectively, in areas colonized by seaweed compared to experimentally cleared areas. Short-term microclimatic variability (minutes-hours) was also significantly reduced, by an average of 78% for temperature and 71% for humidity, under algal canopies during low-tide events. Using seaweed as an example, we develop a conceptual model of the relationship between biological cover and microclimate in the intertidal zone. Disturbance events that remove or drastically reduce seaweed cover mediate shifts between relatively stable and unstable states with respect to mechanical decay and ecological stress associated with heat and desiccation. In urban coastal environments where disturbance may be frequent, facilitating the establishment and recovery of canopy-forming species on rocks and engineered structures could enhance the durability of construction materials as well as support conservation, planning and policy targets for biodiversity enhancement.
Article
Ecological engineering, defined as the design of sustainable ecosystems that integrate human society with its natural environment for the benefit of both, has developed over the last 30 years, and rapidly over the last 10 years. Its goals include the restoration of ecosystems that have been substantially disturbed by human activities and the development of new sustainable ecosystems that have both human and ecological values. It is especially needed as conventional energy sources diminish and amplification of nature's ecosystem services is needed even more. There are now several universities developing academic programs or departments called ecological engineering, ecological restoration, or similar terms, the number of manuscripts submitted to the journal Ecological Engineering continue to increase at an rapid rate, and the U.S. National Science Foundation now has a specific research focus area called ecological engineering. There are many private firms now developing and even prospering that are now specializing in the restoration of streams, rivers, lakes, forests, grasslands, and wetlands, the rehabilitation of minelands and urban brownfields, and the creation of treatment wetlands and phytoremediation sites. It appears that the perfect synchronization of academy, publishing, research resources, and practice is beginning to develop. Yet the field still does not have a formal accreditation in engineering and receives guarded acceptance in the university system and workplace alike.
Article
The ODAS Italia 1 oceanographic buoy is moored in the Ligurian Sea, 37 nm from Genoa, along the Genoa-Cape Corse transect (43° 48.90′ N-09° 06.80′ E), over a 1270 m deep sea bottom. The underwater portion of the buoy is 37 m long and 0.60 m in diameter, acting as a small island for colonization of fouling organisms and as a fish-aggregating device (FAD). The role of the buoy in attracting and maintaining fish assemblages was investigated by visual censuses in different seasons at depths of 0–40 m. Fish from seven families, comprising 12 species, of which three are benthic, were recorded with maximum abundance in summer. Fouling was studied from samples collected on the buoy and on immersed panels. The fouling community of the buoy consisted of 34 algae and 100 animal species, including three fish. The settlement processes of the fouling community on the panels, in particular on those exposed for over 70 months at 12 m and 33 m depth, are described based on counts of settled organisms, the covering index of each taxa and biomass assessments. On the panels, 63 species were identified. The fouling biomass, on the panel submerged for 70 months, assessed as wet weight, reached 2.8 kg/m2 at 12 m depth and 4.8 kg/m2 at 33 m depth. Observations of benthic organisms settled directly on the buoy were made between 1988 and 1989 and when the buoy was retrieved and brought back to shore on April 15, 1991 after 52 months at sea. At this time, the fouling community along the full 37 m length of the buoy was sampled, and 91 taxa, including 83 species, were identified. Several of the species present on the buoy are shallow, coastal species, some with a very short larval period. Possible ways of colonization by such species are discussed. Despite seasonal changes, the pelagic fish community was more stable over the period of 11 years of study than the benthic community settled on the buoy (that is still developing).
Article
Year-round observations on the condition of intertidal seaweeds growing in situ on the shore, show that the upper limits of the zones characterized by Pelvetia canaliculata (L.) Done et Thur., Fucus spiralis L. and Ascophyllum nodosum (L.) Le Jol. were periodically pruned back by environmental conditions. The uppermost plants of each species showed clear signs of tissue damage 21 to 28 days after a time when drying conditions coincided with neap tides which exposed the plant to aerial conditions for long periods. High air temperatures aggravated the damage, but neither frost nor prolonged rain had any obvious adverse effects. On spring tides the plants were wetted every day and no damage resulted regardless of the weather.These species clearly all reach up to their physiological limits on the shore investigated, but presumably Fucus vesiculosus L. and F. serratus L. do not, for they were never observed to show signs of tissue damage attributable to exposure to air. Transplant experiments did, however, prove that F. serratus cannot survive in the F. spiralis zone and nor can F. spiralis persist in the Pelvetia canaliculata zone.Laboratory experiments also demonstrated that the ability to tolerate desiccation and then to resume photosynthesis and growth when re-submerged was greatest in P. canaliculata, the species found highest on the shore, and was progressively less in species inhabiting successively lower levels.
Article
People have caused major impacts on nearshore and intertidal habitats by building infrastructure associated with shipping, recreation, residential and commercial developments. Together with the desire or need to control erosion, these have led to increased “armouring” of intertidal shorelines, with seawalls, revetments, onshore and offshore groynes and other defence systems, piers and docks replacing natural habitats. Despite the long history of such changes, until relatively recently there had been limited research on the impacts of such alterations to shorelines, especially when compared to research into effects of urbanisation on terrestrial habitats. In addition, most research to date has focussed on the impacts of such changes on the ecological structure of assemblages, i.e. the numbers and types of organisms affected, rather than on ecological processes. With the realisation that most coastal infrastructure cannot be removed, there is now an increasing research effort into ways that infrastructure can be built to meet engineering requirements, but to also increase its value as habitat – ecological engineering. In this review, we discuss the major impacts and the experimental research that has been and is being done to build coastal infrastructure in a more biodiversity-friendly manner. Much of the review has focussed on seawalls, which is where most of the experimental work has been done to date. Finally, we raise some concerns about the types of research effort that are still needed and caution against wholesale implementation of what seem like simple remedies, without evidence that they will have the desired effect in the long term.
Article
The world is changing rapidly, ultimately due to the pressure of human population growth driving change at global, regional and local scales. There is convincing and widely accepted evidence that the climate is changing as a result of anthropogenic forcing due to greenhouse gas emissions ([Mitchell et al., 1995], [Lee et al., 2006] and [IPCC, 2007]). Increased concentrations of one greenhouse gas — carbon dioxide is causing a reduction in the pH of the oceans ([Caldeira and Wickett, 2003], [The Royal Society, 2005] and [Doney et al., 2009]). Global trade is also leading to homogenization of floras and faunas as species are deliberately and/or accidentally transported around the world ([Mack et al., 2000], [Kolar and Lodge, 2002] and [Ruiz and Carlton, 2003]; Drake and Lodge, 2004 J.M. Drake and D.M. Lodge, Global hot spots of biological invasions: evaluating options for ballast-water management, Proc. R. Soc. B. 271 (2004), pp. 575–580. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (72)[Drake and Lodge, 2004] and [Rahel, 2007]). Overfishing is occurring globally for large pelagic species at the top of food webs ([Jackson et al., 2001], [Myers and Worm, 2003], [Worm and Myers, 2003], [Heithaus et al., 2008] and [Baum and Worm, 2009]), and at a regional scale for benthic species in most shallow seas ([Solan et al., 2004], [Steneck, 2006], [Kaiser et al., 2007] and [Genner et al., 2010]). Pollution, whilst being more regulated, especially from point sources, is all pervasive (Thompson et al., 2002) and plastic litter is a global problem (Fig. 1; [Thompson et al., 2004] and [Thompson et al., 2009]). Despite preventative efforts, oil spills can still be a major threat to the marine environment ([Southward and Southward, 1978], [Gundlach et al., 1983] and [Hawkins and Southward, 1992]), with the 2010 sinking of the Deepwater Horizon oilrig in the Gulf of Mexico representing one of the worst oil disasters in United States history. The coasts are becoming increasingly developed leading to habitat loss at local and regional scales ([Lotze et al., 2006] and [Airoldi and Beck, 2007]). Responses to rising and stormier seas will inevitably lead to intervention in coastal processes as people and infrastructure will need to be protected, leading to even more coastal habitat modification and loss (Fig. 2; [Airoldi et al., 2005], [Martin et al., 2005], [Moschella et al., 2005], [Bulleri and Chapman, 2010] and [Chapman and Underwood, 2011]).
Article
As a peak in the global number of offshore oil rigs requiring decommissioning approaches, there is growing pressure for the implementation of a "rigs-to-reefs" program in the deep sea, whereby obsolete rigs are converted into artificial reefs. Such decommissioned rigs could enhance biological productivity, improve ecological connectivity, and facilitate conservation/restoration of deep-sea benthos (eg cold-water corals) by restricting access to fishing trawlers. Preliminary evidence indicates that decommissioned rigs in shallower waters can also help rebuild declining fish stocks. Conversely, potential negative impacts include physical damage to existing benthic habitats within the "drop zone", undesired changes in marine food webs, facilitation of the spread of invasive species, and release of contaminants as rigs corrode. We discuss key areas for future research and suggest alternatives to offset or minimize negative impacts. Overall, a rigs-to-reefs program may be a valid option for deep-sea benthic conservation.
Article
Offshore wind farms are the subject of environmental impact assessments in which potential adverse effects are identified and quantified. Those impacts will then require to be mitigated through appropriate design, construction and operation methods. Where environmental impacts cannot be mitigated, operators would be required to compensate the environment or its users for any actual or potential damage. The present study shows that the placement of offshore wind turbines gives the potential for habitat creation, which may thus be regarded as compensation for habitat lost. Using current design criteria and construction methods, the analysis here indicates that the net amount of habitat created by the most common design of offshore wind turbine, the monopile, is up to 2.5 times the amount of area lost through the placement, thus providing a net gain even though the gained habitat may be of a different character to the one that lost. Hence, the study raises important issues for marine nature conservation managers. The study also provides suggestions for further work in order to increase the empirical evidence for the value of mitigation, compensation and habitat creation. Copyright © 2009 John Wiley & Sons, Ltd.
Article
The growth rates of two fish species, the winter flounder Pseudopleuronectes americanus (Walbaum) (19.3 to 42.6 mm total length, TL) and the tautog Tautogaonitis (Linnaeus) (23.9 to 55.9 mm TL), were used to evaluate habitat quality under and around municipal piers in the Hudson River estuary, USA. Growth rates were measured in a series of 10 d field caging-experiments conducted at two large piers in the summers of 1996 and 1997. Cages (0.64 m2) were deployed along␣transects that stretched from underneath the piers to beyond them, encompassing the pier edge (the transitional zone between the pier interior and the outside). Growth in weight (G w ) was determined at five locations along the transect, 40 m beneath the pier, 20 m beneath the pier, at the pier edge, 20 m beyond the pier edge, and 40 m beyond. Under piers, mean growth rates of winter flounder and tautogs were negative (x¯G W = −0.02 d−1), and rates were comparable to laboratory-starved control fishes (x¯G W = −0.02 d−1). In contrast, mean growth rates at pier edges and in open waters beyond piers were generally positive (x¯G W ranged from −0.001 to +0.05 d−1), with growth at pier edges often being more variable and less rapid than at open-water sites. Analyses of stomach contents upon retrieval of caged fishes revealed that dry weights of food were generally higher among fishes caged at open-water stations (x¯ range = 0.02 to 0.72 mg dry wt) than at pier-edge (x¯ range = 0.01 to 0.54 mg) or under-pier (x¯ range = 0.03 to 0.11 mg) stations, although it was apparent that benthic prey were available at all stations on the transect. Our results indicate poor feeding conditions among fishes caged under piers, and suboptimal foraging among fishes caged at pier edges. Inadequate growth rates can lead to higher rates of mortality, and, based on these and other earlier experiments, we conclude that under-pier environments are poor-quality habitats for some species of juvenile fishes.
Article
A hydrodynamic model explaining the mechanism of contact of marine larvae in vertical flows is presented. Two hydrodynamic factors—flow vorticity and larval self-propulsion—are the key components in the mathematical model. It is shown that flow vorticity causes a larva to rotate and change the direction of self-thrust, thus leading to its migration across the mean flow. The latter motion is of an oscillatory nature. Contact will be enabled only for sufficiently large amplitudes of oscillations. Simple expressions for the probability of initial contact are obtained for two-dimensional Couette and Poiseuille flows. The three-dimensional motion of a larva in a tube is studied using the Monte-Carlo simulations. It is shown that contact probability depends mainly on the ratio of the characteristic flow velocity and the larva’s swimming speed. The theoretical results compare favorably with available experimental data. Possible applications of the method and results presented here to the classical problem of larval attachment to bodies of general geometry are briefly discussed in the concluding section.
Article
Four species of balanomorph barnacles, Balanus crenatus Brugire, B. balanoides (L.), Elminius modestus Darwin and Chthamalus stellatus (Poli), were studied to assess the susceptibility of intertidal barnacle species to desiccation. Known sized samples of barnacles were exposed to controlled desiccating conditions and subsequent survival and water loss were determined. It is clear that the ability to live high on the shore is dependent on a reduction of the overall permeability to water loss. Because of greater surface area to volume ratios, small stages are particularly prone to desiccation. In normal intertidal emersion periods, small stages of B. crenatus particularly, and also of B. balanoides and E. modestus which are similar in their desiccation resistance, would be susceptible to desiccation at normal temperatures and low humidities. Large barnacles would be more prone to death from high temperatures when the tide is out. The spat of C. stellatus, although surviving much longer than spat of larger dimensions of the other species, must also be prone to prolonged emersion conditions at high shore levels.
Article
We examined feeding success of young-of-the-year winter flounder (Pseudopleuronectes americanus Walbaum) (20–50 mm TL) around a large, municipal pier in the Hudson River estuary, USA. Replicate, 3-h feeding experiments were conducted using benthic cages (0.64 m2) deployed under, at the edge, and outside of the pier during late spring and early summer in 1998 and 1999. Significantly more winter flounder caged under piers had empty stomachs ( [`(x)]\bar x =71.9%) than at the edge or in open water ( [`(x)]\bar x =29.2% and 14.4%, respectively). Feeding intensity was significantly higher outside of the pier ( [`(x)]\bar x =0.40%) than the edge or under the pier ( [`(x)]\bar x =0.19% and 0.03%, respectively). Simultaneous with feeding experiments, benthic core samples were collected adjacent to cages. Variability was high, but abundances of prey were consistently higher under the pier ( [`(x)]\bar x =200.14±113.3 SD in 1998; 335±290.2 in 1999) than at the edge ( [`(x)]\bar x =126.6±50.2 in 1998; 70.8±68.5 in 1999) or in open water ( [`(x)]\bar x =53.4±16.1 in 1998; 123.8±193.9 in 1999). No significant differences in prey biomass were determined, suggesting that small, numerous prey were available under the pier and fewer, larger taxa were present at the edge and outside. Data indicate that feeding is suppressed among young-of-the-year winter flounder caged under piers in spite of sufficient prey available. Based on these and other experiments we submit that areas under piers are not suitable long-term habitats for juvenile fish because they interfere with normal feeding activities.
Conference Paper
Worldwide demand for renewable energy is increasing rapidly because of the climate problem, and also because oil resources are limited. Wind energy appears as a clean and good solution to cope with a great part of this energy demand. As space is becoming scarce for the installation of onshore wind turbines, offshore wind energy becomes a good alternative. Renewable electricity from wind power can contribute to achieving Kyoto targets for sustainable energy development, but the green image of wind power may be jeopardized if wildlife is adversely affected. This paper deals with a brief revision of the status and development plans of offshore wind power, followed by a critical discussion about the existing challenges and attendant environmental impacts facing the offshore wind energy. Based on the discussions, suggestions are also recommended.
Article
A 4-yr study on the motile epibionts colonizing hydroids on a floating dock in a South Carolina estuary indicated that the motile epibiotic community may impact benthic and nektonic community processes. Permanent members of the epibiotic community were preyed upon by fish, especially when the Atlantic silverside (Menidia menidia (L.)) became reproductively active and deposited eggs among the hydroids during the spring. When fish predation reduced the number of amphipods within the epibiotic community, crab megalopa colonized the hydroids. Crabs developed into juveniles and emigrated from the epibiotic community after 6–8 wk residence. The community on floating docks may be an important food source for some nekton and may recruit some benthic invertebrates.Although preferential larval settlement and fish predation are intuitive processes associated with floating dock communities, insufficient research has addressed the relationships in soft-bottom areas devoid of naturally occurring hard substrata.
Article
Urban structures in the form of pontoons and pilings represent major coastal habitats for marine organisms and understanding the factors causing abundances of organisms to differ between these and natural habitat has been neglected in the study of coastal ecology. It has been proposed that composition of substrata explain differences previously described between subtidal assemblages of epibiota on rocky reef (sandstone) and pontoons (concrete) in Sydney Harbour, Australia. This study tested the hypothesis that differences in the composition of substratum (sandstone vs. concrete) independent of type of habitat (rocky reef vs. pontoon) affects the development of epibiotic assemblages. This was tested by experimentally providing substratum of the two types in both habitats. Epibiotic assemblages were unaffected by the composition of substratum but strongly affected by the type of habitat; demonstrating that pontoons constitute novel habitats for epibiota. This result highlights a need for determining how current ecological understanding of subtidal epibiota, which is heavily based on studies of urban structures (pilings and pontoons), relates to natural reef. Future tests of hypotheses about the nature of these differences will not only contribute to better ecological understanding of epibiota and their use of urban structures as habitats, but also to better predictions of future changes to the ecology of coastal habitats.