Marine ecology seeks to understand the factors that shape biological communities. Progress towards this goal has been hampered by habitat‐centric approaches that ignore the influence of the wider seascape. Coral reef fishes may use non‐reef habitats (e.g. mangrove and seagrass) extensively, yet most studies have focused on within‐reef attributes or connectivity between reefs to explain trends in their distribution and abundance. We systematically review the evidence for multihabitat use by coral reef fishes across life stages, feeding guilds and conservation status. At least 670 species of “coral reef fish” have been observed in non‐reef habitats, with almost half (293 species) being recorded in two or more non‐reef habitats. Of the 170 fish species for which both adult and juvenile data were available, almost 76% were recorded in non‐reef habitats in both life stages. Importantly, over half of the coral reef fish species recorded in non‐reef habitats (397 spp.) were potential fisheries targets. The use of non‐reef habitats by “coral reef” fishes appears to be widespread, suggesting in turn that attempts to manage anthropogenic impacts on fisheries and coral reefs may need to consider broader scales and different forms of connectivity than traditional approaches recommend. Faced with the deteriorating condition of many coastal habitats, there is a pressing need to better understand how the wider seascape can influence reef fish populations, community dynamics, food‐webs and other key ecological processes on reefs.

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Increases in the frequency of perturbations that drive coral community structure, such as severe thermal anomalies and high intensity storms, highlight the need to understand how coral communities recover following multiple disturbances. We describe the dynamics of cover and assemblage composition of corals on exposed inshore reefs in the Palm Islands, central Great Barrier Reef, over 19 years encapsulating major disturbance events such as the severe bleaching event in 1998 and Cyclone Yasi in 2011, along with other minor storm and heat stress events. Over this time, 47.8% of hard coral cover was lost, with a concomitant shift in coral assemblage composition due to taxon-specific rates of mortality during the disturbances, and asymmetric recovery in the aftermath thereof. High recruitment rates of some broadcast-spawning corals, particularly corymbose Acropora spp., even in the absence of adult colonies, indicate that a strong external larval supply replenished the stocks. Conversely, the time required for recovery of slow-growing coral morphologies and life histories was longer than the recurrence times of major disturbances. With interludes between bleaching and cyclones predicted to decrease, the probability of another severe disturbance event before coral cover and assemblage composition approximates historical levels suggests that reefs will continue to erode.

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Habitat edges commonly support discrete communities compared to adjoining habitats in response to unique boundary conditions. Coral reefs are often adjacent to other habitats, e.g. sand or seagrass meadows, but little is known about how reef-associated organisms respond to the presence of edges. Here, we examined fish communities and benthic assemblages at varying distance from a coral reef−sand edge. At 25 sites, 30 m transects were placed at 5 locations: 1 along the edge and at 5 m and 10 m away from the edge into reef and sand habitats. Counts were made of 51 fish species and benthic composition surveyed. The fish community along the edge was substantially different to communities only 5 m into the sand and reef habitats. Overall, 61% of the 51 fish species appeared to respond to the edge, with 43% significantly higher or lower in abundance along the edge compared to other locations. Twelve species showed positive edge responses, including the wrasse Thalassoma lunare, which was 30 times more abundant along the edge compared to 10 m into the reef. Ten species exhibited negative edge responses, including the damselfish Pomacentrus moluccensis, which was 7 times more abundant 10 m into the reef compared to the edge. Feeding ecology appears to influence edge-related distribution patterns, with carnivores and omnivores dominating the edges and planktivores more abundant into the reef. These findings suggest that habitat edges may play an important role in structuring coral reef fish communities. Future research should focus on experimental approaches to identify the underlying mechanisms driving edge responses.

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