Patterns Of Fish Assemblages Research Articles

Ecomorphological Traits Determine Assemblage Pattern of Small Freshwater Fish in Smaller Lentic Aquatic Bodies

The present study investigated ecomorphological patterns of fish assemblage from freshwater ponds on two functional categories, i.e., foraging behavior and habitat preference. Nine ecomorphological indices were derived from eight morphometric variables and examined on 566 adult individuals belonging to 9 species, 7 families and 4 orders. Samples were collected during April 2016 to September 2017 from freshwater ponds in Birbhum, West Bengal. Mantel test was performed to investigate correlation between morphological, taxonomic, trophic and habitat guild matrices. The partial Mantel test was done to investigate the direct correlation between trophic and habitat guilds with morphology discounting the effect of taxonomic relatedness on species assemblage. The interspecific ecomorphological diversification pattern was analysed by HCPC method. At least three ecomorphological assemblages among these fish species with two significant principal axes of variations were observed. Ecomorphological attributes associated with mouth aspect ratio, compression index and relative body height were on PC1 axis, and relative length and height of head, relative area of eye were on PC 2 axis. Mantel and partial Mantel test showed significant correlation between morphology and trophic guild structure. Outcomes show that morphology is a good predictor of trophic structure of fish assemblage in studying convergent assemblage pattern irrespective of taxonomy.

Integrating freshwater wetland science into planning for Great Barrier Reef sustainability

Abstract The paper ‘Biodiversity values of remnant freshwater floodplain lagoons in agricultural catchments: evidence for fish of the Wet Tropics bioregion, northern Australia’, published in Aquatic Conservation: Marine and Freshwater Ecosystems in 2015, has contributed in several ways to the integration of freshwater wetland science within new catchment management policies and practices for Great Barrier Reef (GBR) sustainability. The Tully–Murray biodiversity study developed novel protocols to sample larval, juvenile, and adult fish life‐history stages in floodplain lagoons using a combination of boat‐based backpack electrofishing and fyke netting. In addition, hydrological and hydrodynamic models were applied in a completely new way to quantify the timing, extent, and duration of water connectivity across floodplain streams, cane drains, and wetlands. Combining the two novel approaches enabled an analysis of lagoon fish assemblage patterns in relation to environmental gradients, especially floodplain hydrology, connectivity patterns, and measures related to agricultural land use. In demonstrating the importance of different levels of connectivity for different biodiversity outcomes in freshwater floodplain lagoons of the Tully–Murray catchment, the subject paper established that floodplain connectivity needs to be taken into consideration in wetland management practices. The timing of the subject publication was fortuitous. It coincided with the preparation of the evidence‐based 2017 Scientific Consensus Statement on land‐based water quality impacts on the GBR. As one of the few freshwater wetland ecology publications for the catchments of the GBR at that time, this paper played an important role in demonstrating freshwater wetland values, fish conservation options, and management imperatives to sustain wetland ecological health and services in GBR catchments. By advancing the understanding of factors driving biodiversity patterns, and the importance of connectivity and ecohydrological processes in freshwater floodplain wetlands of the GBR catchment, the Tully–Murray study helped to drive new policy directives for the protection and restoration of catchment, floodplain, and estuary functions, and connectivity, now embedded in the Reef 2050 Long‐Term Sustainability Plan 2018, an overarching strategy for managing the GBR over the next 35 years, and complementary Queensland environmental legislation.

Altered tropical seascapes influence patterns of fish assemblage and ecological functions in the Western Indian Ocean

The arrangement and composition of habitats within landscapes and fine-scale habitat characteristics influence community structure and ecological processes. These aspects can be altered by anthropogenic activities, thus influencing associated assemblages. Farming of macroalgae is a common practice in tropical settings and alters the natural composition of seascapes by introducing monoculture patches. The farmed macroalgae may also differ in palatability compared to naturally-occurring macroalgae, influencing herbivory. This study assessed how these farms may differ from natural macroalgal beds in terms of habitat heterogeneity, fish assemblages, and herbivory. We surveyed fish assemblages and deployed macroalgal assays within macroalgal beds, farms and at varying distances from these habitats near Mafia Island, Tanzania. Fish composition and herbivory differed between the habitats likely due to different macrophyte species richness, underlying hard substrate in natural macroalgal beds, and high abundance of browsers nearby the farms. Additionally, fish assemblage patterns and herbivory were not consistent across the seascapes and varied with distance from the focal habitats possibly due to the presence of other habitats. The results suggest alterations of seascapes by farming practices may have consequences on fish assemblages and the ecological functions performed, thus positioning of farms should be carefully considered in management and conservation plans.

Fish Assemblage Structure Comparison between Freshwater and Estuarine Habitats in the Lower Nakdong River, South Korea

Variabilities of biological communities in lower reaches of urban river systems are highly influenced by artificial constructions, alterations of flow regimes and episodic weather events. Impacts of estuary weirs on fish assemblages are particularly distinct because the weirs are disturbed in linking between freshwater and estuarine fish communities, and migration successes for regional fish fauna. This study conducted fish sampling at the lower reaches of the Nakdong River to assess spatio-temporal variations in fish assemblages, and effects of estuary weir on structuring fish assemblage between freshwater and estuary habitats. In total, 20,386 specimens comprising 78 species and 41 families were collected. The numerical dominant fish species were Tachysurus nitidus (48.8% in total abundance), Hemibarbus labeo (10.7%) and Chanodichthys erythropterus (3.6%) in the freshwater region, and Engraulis japonicus (10.0%), Nuchequula nuchalis (7.7%) and Clupea pallasii (5.2%) in the estuarine site. The fish sampled were primarily small species or the juveniles of larger species at the estuary region, while all life stages of fishes were observed at the freshwater habitats. The diversity patterns of fish assemblages varied greatly according to study site and season, with higher trends at estuarine sites during the warm-rainy season. No significant difference in diversity between freshwater and estuarine sites during the cold-dry season were found. Multivariate analyses of fish assemblage showed spatial and seasonal differences of assemblage structures. Higher effects of between-site variability but not within seasonal variability at each site were observed. Variations in assemblage structures were due to different contributions of dominant species in each habitat. Common freshwater species characterized the fish assemblage in the freshwater region, while marine juveniles were significantly associated with the estuarine habitat. The results from the ecological guild analyses showed distinct ecological roles for freshwater and marine species, and overlapping roles for fish sampled at the fishways. The lower reaches of the Nakdong River are an important ecosystem for both freshwater and marine juveniles. Nakdong River estuarine residents and migrant fishes, however, have been negatively affected by the construction of the weir (gravity dam), due to the obstruction to migration from and to freshwater habitats. Conservation and management policies aimed at minimizing anthropogenic influences on estuary ecosystems should focus on evaluating ecological functions of estuary weirs.

The effects of ecoregions and local environmental characteristics on spatial patterns in boreal riverine fish assemblages

AbstractThe conservation, management and monitoring of aquatic resources should benefit from understanding their spatial structuring. In this paper, we used the reference condition approach (RCA) to test if the variability in biotic communities, riverine fish assemblages in the present case, is better controlled with a spatial delineation based on ecoregions or by grouping rivers with local catchment characteristics. Electrofishing data from 493 riffles in 99 rivers in Finland were used in the analysis. We completed multivariate analyses (nonmetric multidimensional scaling, multiresponse permutation procedures) to identify differences in fish community composition among groups based on ecoregions or catchment characteristics. We concluded that both regional processes and local environmental characteristics structured fish populations, and bioassessment of freshwaters should be based on regional spatial delineations, supported by local scale characteristics. Spatial delineations like ecoregions should be used to assist the bioassessment to improve the efficiency to detect the human impacts.

Diel and seasonal variation in fish communities in the Zhongjieshan marine island reef reserve

Marine reserves are essential for the conservation of fishery resources. However, marine island reef as a natural reserve is poorly developed, mainly because the ecological patterns of fishes in such areas remain little known. Here, we attempt to uncover the diel and seasonal patterns of fish assemblage in the Zhongjieshan Archipelago, which is a typical marine island reef biotope, located at the junction of the Yangtze and Qiantang rivers in the East China Sea. Fish communities in this area are mainly composed of continental shelf demersal fishes, continental shelf benthopelagic fishes, and continental shelf pelagic-neritic fishes. Among them, continental shelf demersal fishes tend to occur in the daytime or during autumn, continental shelf benthopelagic fishes at night or during summer, and continental shelf pelagic-neritic fishes in the daytime or during spring. Seasonal migratory fishes are mainly observed during spring and summer. Moreover, alternate and migration indices showed the lowest stability of the community in the daytime and during winter, revealing that fishes prefer to occur around the island reef at night or in the day-night time. Such patterns are mainly affected by the seasonal shift, predominant communities, and diel alternation. These findings will greatly help develop the sustainable fishing strategy and construct the marine island reef reserve for the conservation of fishery resources.

Habitat associations and assemblage structure of demersal deep-sea fishes on the eastern Flemish Cap and Orphan Seamount

Advancements in remote-sampling and optical technologies have considerably improved our understanding of fish-habitat relationships and assemblage structure in the deep ocean through direct observations. The composition and complexity of seafloor habitats can strongly influence species diversity and distributions, but the relative importance of different microhabitats - both abiotic and biotic - is poorly understood. We examined differences in fish species composition and relative abundance between different physical (sediment type and boulder density) and biological (coral and sponge densities) habitat categories through in-situ observations from remotely-operated vehicle surveys of unglaciated deep-sea features off the coast of Newfoundland, Canada. Fish-habitat relationships were observed across 61 km of seafloor and spanning depths of 875–3003 m at five dive locations, with additional quantification of fish behaviour and assemblage patterns. Distinct assemblages occurred among depth zones (ANOSIM, Global R = 0.47, p = 0.001), although global tests of overall biological and physical habitats were not significant. Significant pairwise differences in assemblages were only observed in more complex physical habitats (e.g. boulder fields, and outcrops) and complex biological habitats (e.g. dense corals) compared to less complex areas of fine-grain sediment or locations with no or few corals and sponges present. Our results suggest overall structural complexity of physical and biogenic habitat features may be particularly important to some deep-sea fishes. Until further details of these relationships can be explored, conservation efforts should strive to protect a wide-range of microhabitats to preserve valuable fish habitats in the deep-ocean environment.

Complementary responses of stream fish and benthic macroinvertebrate assemblages to environmental drivers in a shale-gas development area

Shale-gas production could impact freshwater quality through contamination of the physical and chemical habitat (e.g., fracturing fluids, untreated or treated effluent) or development-related impacts. Despite environmental concerns, information is lacking to support biomonitoring as a diagnostic tool to assess impacts of shale-gas production. We characterized water quality and biota in areas of high shale gas potential (Early Carboniferous bedrock in New Brunswick, Canada) and surrounding geologic areas, and we assessed patterns in benthic macroinvertebrate (BMI) and fish assemblages. Early Carboniferous stations differed primarily based on water chemistry, and BMI were associated with a gradient in conductivity and temperature across geologic classes. Concordance analysis indicated similar classification of stations by both organism groups, though fish were more related to turbidity and nutrients. Concordance among fish and BMI was strongest at high conductivity, Early Carboniferous stations. These results suggest that geology plays a strong role in driving abiotic habitats and biotic communities of streams, even at small spatial scales. Furthermore, they suggest BMI and fish can provide complementary information for biomonitoring in shale-gas development areas, with BMI responding to increased ion concentrations from surface water contamination, and fish responding to changes in nutrients and turbidity resulting from development.

Effects of habitat structural complexity on diversity patterns of neotropical fish assemblages in the Bita River Basin, Colombia

Several studies have shown that fish assemblages are structured by habitat features, most of them have proposed that there is a positive relationship between habitat structural complexity and species diversity. In this study, we aimed to test this positive-relationship idea in three habitats types (creeks, oxbow lakes and river sandbanks) distributed along the Bita River Basin in South America. Standardized surveys were conducted during January and February of 2016 (low water period) in 30 sites distributed along the entire basin. We recorded 23,092 individuals representing 191 species. To investigate possible relationships between habitat structural complexity and species diversity, we calculated the first three Hill’s numbers, and performed a Non-metric Multidimensional Scaling (NMDS), a Principal Component Analysis (PCA) and a Canonical Correspondence Analysis (CCA). Our results showed that river sandbanks and creeks had the highest species richness. Results from the NMDS analysis (stress = 0.19) showed that fish community composition was different in the assessed habitats (ANOSIM < p = 0.001). According to the results of the principal component analysis, sand percentage, dissolved oxygen, and vegetation width separated river sandbanks from the other habitats. Results from the Hill’s numbers, forward selection procedure, and canonical correspondence analysis suggested that species composition and diversity were significantly influenced by the habitat structural complexity index and conductivity.

Effects of habitat structural complexity on diversity patterns of neotropical fish assemblages in the Bita river basin, Colombia

Effects of habitat structural complexity on diversity patterns of neotropical fish assemblages in the Bita river basin, Colombia

Quantifying the Distribution and Diversity of Fish Species Along Elevational Gradients in the Weihe River Basin, Northwest China

In this study, species compositions, distributions, and diversity patterns of fish assemblages were investigated at 50 sampling sites in the Weihe River and its two largest tributaries, the Jinghe River and the Beiluo River, under high- and low-flow conditions in 2017. For every condition tested and in the all rivers tested, Cyprinidae was the richest family, containing 17 of the 39 identified fish species. Carassius auratus was the most common species, accounting for 11.3% of the total individuals. Nonmetric multidimensional scaling (NMDS), analysis of similarities (ANOSIM), and similarity percentage analysis (SIMPER) revealed that fish species composition differed significantly among rivers (p &lt; 0.05), with dissimilar species assemblages found in the different rivers. Variation was influenced by a combined effect of habitat conditions, environmental factors, and human impact. Canonical correspondence analysis (CCA) identified variables explaining the variation in fish species (p &lt; 0.05), and elevation contributed the most under both flow conditions. Alpha diversity decreased with increasing elevation within rivers as a result of changing environmental conditions, especially for wetted width. Alpha and beta diversities of rivers increased with increasing drainage area, which is related to habitat heterogeneity. The decrease in alpha diversity and the increase in beta diversity with increasing elevation can be explained by variations in habitat and geographic features.

Abundance–occupancy patterns in a riverine fish assemblage

Abstract The interspecific relationships between abundance and site occupancy have been widely studied in plants and animals, but principally in terrestrial systems. With few exceptions, a positive abundance–occupancy relationship has been reported. Few publications have included freshwater fish, possibly suggesting a general lack of abundance–occupancy patterns for this taxonomic group. We examined the relationship between abundance and the extent of site occupancy by 145 species of freshwater fish, including nine non‐indigenous species, sampled over 85 sites spread across the Duck River Basin, Tennessee, U.S.A. A distinct (r2 = 0.79) positive abundance–occupancy curve was observed, with curves differing relative to feeding and size guilds, but not relative to environmental tolerance, conservation status (i.e. listed/non‐listed), or origin (i.e. indigenous/non‐indigenous). The patterns observed are consistent with those reported in many studies of terrestrial taxa. The existence of positive abundance–occupancy relationships in stream fish has at least two major implications for fish conservation. First, species that decrease in occupancy due to anthropogenic disturbances are likely to decrease in abundance, facing inflated prospects for local extinction. Second, occupancy alone may be used to index community status and the need for, or success of, conservation activities.

Biodiversity pattern of fish assemblages in Poyang Lake Basin: Threat and conservation.

Poyang Lake Basin is of great importance to maintain regional ecological balance. However, fish biodiversity in this basin has rapidly declined as the result of anthropogenic habitat alteration, such as dam construction, sand mining, and water pollution. Here, we aimed to analyze the temporal and spatial changes in biodiversity patterns of fish in Poyang Lake Basin over the last 37 years. The number of fish species underwent a significant decrease in the current period. In particular, 36.7% of the migration of fish was extirpated. Twenty‐seven fish species have been formally assessed using the Chinese Red List were currently listed as Critically Endangered (9), Endangered (3), Vulnerable (10), and Near Threatened (5). Alpha and gamma diversity revealed that fish diversity had also decreased, and beta diversity showed significant composition dissimilarity in two periods. PCoA showed that the historical fish composition dissimilarity was significantly different from that of the current period. We found a significant effect of the geographical distance on the spatial turnover component for the historical and current periods. In addition, the nestedness component was the main contributor to beta diversity, which indicated one large protected area should be established in Poyang Lake and the Ganjiang River Basin with higher species richness. These results indicated that fish biodiversity declined in the current period likely caused by anthropogenic habitat alteration and other threatened factors. Therefore, we suggest that the habitat reconstruction and biodiversity conservation for fish have become imperative in this basin, and a complete management plan should be carried out.

A New Zealand demersal fish classification using Gradient Forest models

ABSTRACTSpatial classifications of the environment have previously been used to characterise biodiversity and to facilitate management planning at large spatial scales. Such classifications are more likely to be adopted if they can demonstrate integration of real patterns in habitats or biotic assemblages, in addition to environment. A previous classification used Gradient Forest analysis to derive 30 classes based on demersal fish assemblage patterns and environmental gradients. Here we provide a detailed description of the similarities and differences in the environment and fish assemblages of classes resulting from an updated classification using the same methodology. Environmental differences were associated with varying levels of differences in the distributions of fish species. At broad spatial scales, assemblages are differentiated primarily according to oceanographic conditions such as temperature and depth; at finer scales, patterns in species assemblages are more closely associated with more localised environmental conditions such as productivity, sea-surface temperature gradients and tidal currents. The 30-group classification allows complex biodiversity information to be summarised in ways accessible to stakeholder and environmental managers. Given the hierarchical nature of the classification, there is considerable scope to use a larger number of groups for applications at regional to local scales.

Large-scale cascaded dam constructions drive taxonomic and phylogenetic differentiation of fish fauna in the Lancang River, China

The establishment of widespread non-native species and the loss of native species driven by multiple anthropogenic disturbances have led to a dramatic reconfiguration of current biodiversity. Trends towards homogenization or differentiation of fish fauna due to the impact of both introductions and extirpations on the taxonomic facet of biodiversity have been observed worldwide, while such effects on the phylogenetic facet have seldom been quantified. Here, we measured the spatio-temporal changes in taxonomic and phylogenetic dissimilarities of fish assemblages among 12 mainstream reaches of the Lancang River against the background of large-scale cascaded dam construction. We found that both the taxonomic and phylogenetic structures of fish assemblages exhibited heterogeneity due to the reduction in the distribution area of common native species and imbalanced invasion by non-native species, which resulted from habitat fragmentation caused by the large-scale cascaded dam construction. Furthermore, changes in taxonomic and phylogenetic dissimilarities were highly correlated. Patterns of fish assemblage based on both taxonomic and phylogenetic structures showed clear spatio-temporal differences due to the imbalance of regional changes, namely, small changes upstream and large changes downstream. This study revealed that taxonomic and phylogenetic dissimilarities could increase in dam-fragmented habitats via imbalanced native species loss and non-native species invasion. Therefore, the risk of a generally positive interpretation of taxonomic and phylogenetic differentiation is highlighted, which should be highly important to ecologists and conservationists.

Biogeographic freshwater fish pattern legacy revealed despite rapid socio‐economic changes in China

AbstractUnderstanding drivers of freshwater fish assemblages is critically important for biodiversity conservation strategies, especially in rapidly developing countries, which often have environmental protections lagging behind economic development. The influences of natural and human factors in structuring fish assemblages and their relative contributions are likely to change given the increasing magnitude of human activities. To discriminate natural and human drivers of fish diversity and assemblage patterns in developing countries with rapid socio‐economic development, a dataset of 908 freshwater fish species and 13 metrics including three categories of both natural (i.e., biogeographic) and human drivers (i.e., economic growth, inland fisheries) in China were analysed with machine learning algorithms (i.e., self‐organizing map, random forest). Here, we found that biogeographic drivers explained 21.8% of the observed fish assemblage patterns in China and remained stronger predictors when compared to human drivers (i.e., 15.6%, respectively). Freshwater fish species richness was positively correlated to rainfall, air temperature, surface water area and inland fisheries production but negatively correlated with urbanization. In addition, the strong structuring effects of climatic variables on Chinese fish richness patterns suggested that the fish assemblages could be particularly vulnerable to climate change. Our results showed that natural biogeographic factors still dominate in driving freshwater fish assemblage patterns despite increased human disturbances on aquatic ecosystems in a rapidly developing country. These findings consequently suggested that we should consider both natural (e.g., climate) and human (e.g., urbanization, inland fisheries) factors when establishing aquatic conservation strategies and priorities for developing countries that are experiencing rapid socio‐economic changes.

Contrasting distribution and foraging patterns of herbivorous and detritivorous fishes across multiple habitats in a tropical seascape

Understanding drivers behind patterns of functionally important groups of fishes is crucial for successful management and conservation of tropical seascapes. Herbivorous fishes are the most prominent consumers of marine primary production which can have profound effects on reef resilience. We explored environmental variables affecting distribution and foraging patterns of herbivorous and detritivorous fish assemblages (siganids, acanthurids and parrotfish) across distinct shallow-water habitats (coral reefs, macroalgae beds and seagrass meadows) during September–November 2016 at Mafia Island, Tanzania (8°00′S, 39°41′E). We performed underwater visual census to quantify fish assemblages, measured habitat features, deployed macroalgal assays and conducted inventories of grazing scars. Multi-dimensional scaling and mixed-effects linear models were used to evaluate differences in fish assemblages and environmental variables influencing abundance and foraging patterns of fishes. Fish communities of focal functional groups differed among habitats. Abundance of herbivores and detritivores as well as relative browsing and scraping was highest on coral reefs compared to macroalgae and seagrass meadows. Adult fish were more abundant on coral reefs while juveniles were abundant in macroalgal beds. Coral cover and crustose coralline algal cover had a positive effect on the abundance of fish in coral reef areas, while macroalgal cover had a negative effect. Contrastingly, in macroalgae habitats, macroalgal cover had a positive effect on the abundance of parrotfish. These results highlight the importance of considering connectivity between macroalgal beds and coral reefs through ontogenetic shifts in habitat use by primarily microphagous parrotfish and of incorporating a range of habitats within coastal management plans.

Strong fish assemblage patterns persist over sixteen years in a warming marine park, even with tropical shifts

Spatial conservation plans representing existing patterns of biodiversity in Marine Protected Areas (MPAs) should be robust to changes over 10 to 20 years, a temporal scale over which MPA plans are often retained. Using data from MPAs where changes have been detected due to ocean warming, can help inform discussion on how to increase temporal robustness in planning. Our aim was to determine how well fish assemblage patterns, used to develop a Habitat Classification System (HCS) as a coarse biodiversity surrogate in MPA planning, persisted over a 16 year timeframe in a warming region (east coast subtropics) of Australia. We analysed persistence/change in fish assemblage patterns in the Solitary Islands Marine Park (SIMP) where species shifts and habitat changes associated with ocean warming have been detected. Fish relative abundance was recorded at 12 sites over 16 years (2001–2017) using roving timed counts. Strong cross-shelf patterns were maintained over that 16 year period, which included some large-scale disturbances (destructive storms, 2016 mass coral bleaching event). Overall persistence in these broad assemblage patterns suggest a well-designed HCS can be a robust tool for coarsely representing biodiversity patterns in a warming world at decadal scales. ‘Tropicalisation’ was detected in some categories, suggesting additional planning strategies are needed within those and beyond decadal plans.

Cross and long-shore variations in reef fish assemblage structure and implications for biodiversity management

Fish communities are an important cultural, recreational and commercial resource that also have an important role in the functioning of marine ecosystems. Around the world fish assemblages are experiencing pressures from anthropogenic activities, and marine spatial planning is being established to mitigate these impacts and assist with biodiversity conservation. Information about how fish assemblages are structured across a range of spatial scales which encompass variations in physical, biotic and environmental parameters will assist marine spatial planning and management. We investigated differences in reef fish assemblage composition over three reef lines across an inshore to offshore gradient (3–23 m depth) at two marine reserves (70 km apart) in the Perth metropolitan region, Western Australia. There were significant increases in the number of individuals, species richness, and relative abundance of fish species across the shallow shelf depth gradient in the two locations. There were distinct fish assemblages associated with each reef line, correlated to depth and distance from shore. The differences across the shelf gradient, even over this small depth range, were greater than the differences between the two locations. These findings have implications for marine spatial management and the design of marine reserves that aim to conserve biodiversity. It may be most appropriate for such marine reserves to encompass a wide depth gradient, rather than a large longshore area. At the very least, cross and longshore patterns in fish assemblages should be taken into consideration and used to guide spatial management plans for biodiversity conservation.

Effects of seascape connectivity on reserve performance along exposed coastlines.

Seascape connectivity (landscape connectivity in the sea) can modify reserve performance in low-energy marine ecosystems (e.g., coral reefs, mangroves, and seagrass), but it is not clear whether similar spatial linkages also shape reserve effectiveness on high-energy, exposed coastlines. We used the surf zones of ocean beaches in eastern Australia as a model system to test how seascape connectivity and reserve attributes combine to shape conservation outcomes. Spatial patterns in fish assemblages were measured using baited remote underwater video stations in 12 marine reserves and 15 fished beaches across 2000 km of exposed coastline. Reserve performance was shaped by both the characteristics of reserves and the spatial properties of the coastal seascapes in which reserves were embedded. Number of fish species and abundance of harvested fishes were highest in surf-zone reserves that encompassed >1.5 km of the surf zone; were located < 100 m to rocky headlands; and included pocket beaches in a heterogeneous seascape. Conservation outcomes for exposed coastlines may, therefore, be enhanced by prioritizing sufficiently large areas of seascapes that are strongly linked to abutting complementary habitats. Our findings have broader implications for coastal conservation planning. Empirical data to describe how the ecological features of high-energy shorelines influence conservation outcomes are lacking, and we suggest that seascape connectivity may have similar ecological effects on reserve performance on both sheltered and exposed coastlines.