Biological

Bleaching and disease are decimating coral reefs especially when warming promotes bleaching pathogens, such as Vibrio coralliilyticus. We demonstrate that sterilized washes from three common corals suppress V. coralliilyticus but that this defense is compromised when assays are run at higher temperatures. For a coral within the ecologically critical genus Acropora, inhibition was 75 to 154% greater among colonies from coral-dominated marine protected areas versus adjacent fished areas that were macroalgae-dominated.

Bleaching and disease are decimating coral reefs especially when warming promotes bleaching pathogens, such as Vibrio coralliilyticus. We demonstrate that sterilized washes from three common corals suppress V. coralliilyticus but that this defense is compromised when assays are run at higher temperatures. For a coral within the ecologically critical genus Acropora, inhibition was 75 to 154% greater among colonies from coral-dominated marine protected areas versus adjacent fished areas that were macroalgae-dominated.

The ecology of many coral reefs has changed markedly over recent decades in response to various combinations of local and global stressors. These ecological changes have important implications for the abundance of taxa that regulate the production and erosion of skeletal carbonates, and thus for many of the geo‐ecological functions that coral reefs provide, including reef framework production and sediment generation, the maintenance of reef habitat complexity and reef growth potential.

Coral reefs underpin a range of ecosystem goods and services that contribute to the well‐being of millions of people. However, tropical coral reefs in the Anthropocene are likely to be functionally different from reefs in the past. In this perspective piece, we ask, what does the Anthropocene mean for the provision of ecosystem services from coral reefs? This synthesis of the coral reef ecosystem services literature suggests the field is poorly prepared to understand the changing service provision anticipated in the Anthropocene.

The inherent complexity of high‐diversity systems can make them particularly difficult to understand. The relatively recent introduction of functional approaches, which seek to infer ecosystem functioning based on species’ ecological traits, has revolutionized our understanding of these high-diversity systems. Today, the functional structure of an assemblage is widely regarded as a key indicator of the status or resilience of an ecosystem. Indeed, functional evaluations have become a mainstay of monitoring and management approaches.

Our global analysis of nearly 1,800 tropical reefs reveals how the intensity of human impacts in the surrounding seascape, measured as a function of human population size and accessibility to reefs (“gravity”), diminishes the effectiveness of marine reserves at sustaining reef fish biomass and the presence of top predators, even where compliance with reserve rules is high. Critically, fish biomass in high-compliance marine reserves located where human impacts were intensive tended to be less than a quarter that of reserves where human impacts were low.

Long-term ecological monitoring of reef fish populations often requires the simultaneous collection of data on benthic habitats in order to account for the effects of these variables on fish assemblage structure. Here, we described an approach to benthic surveys that uses photogrammetric techniques to facilitate the extraction of quantitative metrics for characterization of benthic habitats from the resulting three-dimensional (3D) reconstruction of coral reefs. 

The ocean has been experiencing substantial changes in marine physics, chemistry and biology including ocean acidification, rising seawater temperature, ocean deoxygenation and sea level rise. These four, often interacting factors, are expected to increase over the coming decades depending on the concentration of greenhouse gases in the atmosphere. It is imperative that international decision-makers and stakeholders understand the enormous role the ocean plays in sustaining life on Earth, and the consequences of a high CO2 world for the ocean and society.

Difficulties in scaling up theoretical and experimental results have raised controversy over the consequences of biodiversity loss for the functioning of natural ecosystems. Using a global survey of reef fish assemblages, we show that in contrast to previous theoretical and experimental studies, ecosystem functioning (as measured by standing biomass) scales in a nonsaturating manner with biodiversity (as measured by species and functional richness) in this ecosystem.

Scientists have advocated for local interventions, such as creating marine protected areas and implementing fishery restrictions, as ways to mitigate local stressors to limit the effects of climate change on reef-building corals. However, in a literature review, we find little empirical support for the notion of managed resilience. We outline some reasons for why marine protected areas and the protection of herbivorous fish (especially parrotfish) have had little effect on coral resilience.