Regime shifts in rocky intertidal communities associated with a marine heatwave and disease outbreak.

Long-term, large-scale experimental studies provide critical information about how global change influences communities. When environmental changes are severe, they can trigger abrupt transitions from one community type to another leading to a regime shift. From 2014 to 2016, rocky intertidal habitats in the northeast Pacific Ocean experienced extreme temperatures during a multi-year marine heatwave (MHW) and sharp population declines of the keystone predator Pisaster ochraceus due to sea star wasting disease (SSWD).

Resistance of rocky intertidal communities to oceanic climate fluctuations.

A powerful way to predict how ecological communities will respond to future climate change is to test how they have responded to the climate of the past. We used climate oscillations including the Pacific Decadal Oscillation (PDO), North Pacific Gyre Oscillation, and El Niño Southern Oscillation (ENSO) and variation in upwelling, air temperature, and sea temperatures to test the sensitivity of nearshore rocky intertidal communities to climate variability. Prior research shows that multiple ecological processes of key taxa (growth, recruitment, and physiology) were sensitive to environmental variation during this time frame.

Testing effects of bottom-up factors, grazing, and competition on New Zealand rocky intertidal algal communities.

Top-down and bottom-up factors and their interaction highlight the interdependence of resources and consumer impacts on food webs and ecosystems. Variation in the strength of upwelling-mediated ecological controls (i.e.

Community theory: Testing environmental stress models.

Intensifying climate change and an increasing need for understanding its impacts on ecological communities places new emphasis on testing environmental stress models (ESMs). Using a prior literature search plus references from a more recent search, I evaluated empirical support for ESMs, focusing on whether consumer pressure on prey decreased (consumer stress model; CSM) or increased (prey stress model; PSM) with increasing environmental stress. Applying the criterion that testing ESMs requires conducting research at multiple sites along environmental stress gradients, the analysis found that CSMs were most frequent, with 'No Effect' and PSMs occurring at low but similar frequencies.

Increasing instability of a rocky intertidal meta-ecosystem.

Climate change threatens to destabilize ecological communities, potentially moving them from persistently occupied "basins of attraction" to different states. Increasing variation in key ecological processes can signal impending state shifts in ecosystems. In a rocky intertidal meta-ecosystem consisting of three distinct regions spread across 260 km of the Oregon coast, we show that annually cleared sites are characterized by communities that exhibit signs of increasing destabilization (loss of resilience) over the past decade despite persistent community states.

Biogeography of ocean acidification: Differential field performance of transplanted mussels to upwelling-driven variation in carbonate chemistry.

Ocean acidification (OA) represents a serious challenge to marine ecosystems. Laboratory studies addressing OA indicate broadly negative effects for marine organisms, particularly those relying on calcification processes. Growing evidence also suggests OA combined with other environmental stressors may be even more deleterious.

Remote sensing: generation of long-term kelp bed data sets for evaluation of impacts of climatic variation.

A critical tool in assessing ecosystem change is the analysis of long-term data sets, yet such information is generally sparse and often unavailable for many habitats. Kelp forests are an example of rapidly changing ecosystems that are in most cases data poor. Because kelp forests are highly dynamic and have high intrinsic interannual variability, understanding how regional-scale drivers are driving kelp populations-and particularly how kelp populations are responding to climate change-requires long-term data sets.

Regional processes are stronger determinants of rocky intertidal community dynamics than local biotic interactions.

Understanding the relative roles of species interactions and environmental factors in structuring communities has historically focused on local scales where manipulative experiments are possible. However, recent interest in predicting the effects of climate change and species invasions has spurred increasing attention to processes occurring at larger spatial and temporal scales. The "meta-ecosystem" approach is an ideal framework for integrating processes operating at multiple scales as it explicitly considers the influence of local biotic interactions and regional flows of energy, materials, and organisms on community structure.

Generality in multispecies responses to ocean acidification revealed through multiple hypothesis testing.

Decades of research have demonstrated that many calcifying species are negatively affected by ocean acidification, a major anthropogenic threat in marine ecosystems. However, even closely related species may exhibit different responses to ocean acidification and less is known about the drivers that shape such variation in different species. Here, we examine the drivers of physiological performance under ocean acidification in a group of five species of turf-forming coralline algae.

Fundamental contradictions among observational and experimental estimates of non-trophic species interactions.

The difficulty of experimentally quantifying non-trophic species interactions has long troubled ecologists. Increasingly, a new application of the classic "checkerboard distribution" approach is used to infer interactions by examining the pairwise frequency at which species are found to spatially co-occur. However, the link between spatial associations, as estimated from observational co-occurrence, and species interactions has not been tested.

Transformative Research Is Not Easily Predicted.

Transformative research (TR) statements in scientific grant proposals have become mainstream. However, TR is defined as radically changing our understanding of a concept, causing a paradigm shift, or opening new frontiers. We argue that it is rarely possible to predict the transformative nature of research.

Incorporating Context Dependency of Species Interactions in Species Distribution Models.

Species distribution models typically use correlative approaches that characterize the species-environment relationship using occurrence or abundance data for a single species. However, species distributions are determined by both abiotic conditions and biotic interactions with other species in the community. Therefore, climate change is expected to impact species through direct effects on their physiology and indirect effects propagated through their resources, predators, competitors, or mutualists.

A keystone ecologist: Robert Treat Paine, 1933-2016.

Robert T. Paine, who passed away on 13 June 2016, is among the most influential people in the history of ecology. Paine was an experimentalist, a theoretician, a practitioner, and proponent of the "ecology of place," and a deep believer in the importance of natural history to ecological understanding.

Long-term declines in an intertidal foundation species parallel shifts in community composition.

The earth is in the midst of a biodiversity crisis, and projections indicate continuing and accelerating rates of global changes. Future alterations in communities and ecosystems may be precipitated by changes in the abundance of strongly interacting species, whose disappearance can lead to profound changes in abundance of other species, including an increase in extinction rate for some. Nearshore coastal communities are often dependent on the habitat and food resources provided by foundational plant (e.

Correction: Sea Star Wasting Disease in the Keystone Predator Pisaster ochraceus in Oregon: Insights into Differential Population Impacts, Recovery, Predation Rate, and Temperature Effects from Long-Term Research.

[This corrects the article DOI: 10.1371/journal.pone.

Interacting environmental mosaics drive geographic variation in mussel performance and predation vulnerability.

Although theory suggests geographic variation in species' performance is determined by multiple niche parameters, little consideration has been given to the spatial structure of interacting stressors that may shape local and regional vulnerability to global change. Here, we use spatially explicit mosaics of carbonate chemistry, food availability and temperature spanning 1280 km of coastline to test whether persistent, overlapping environmental mosaics mediate the growth and predation vulnerability of a critical foundation species, the mussel Mytilus californianus. We find growth was highest and predation vulnerability was lowest in dynamic environments with frequent exposure to low pH seawater and consistent food.

Sea Star Wasting Disease in the Keystone Predator Pisaster ochraceus in Oregon: Insights into Differential Population Impacts, Recovery, Predation Rate, and Temperature Effects from Long-Term Research.

Sea star wasting disease (SSWD) first appeared in Oregon in April 2014, and by June had spread to most of the coast. Although delayed compared to areas to the north and south, SSWD was initially most intense in north and central Oregon and spread southward. Up to 90% of individuals showed signs of disease from June-August 2014.

Are large macroalgal blooms necessarily bad? Nutrient impacts on seagrass in upwelling-influenced estuaries.

Knowledge of nutrient pathways and their resulting ecological interactions can alleviate numerous environmental problems associated with nutrient increases in both natural and managed systems. Although not unique, coastal systems are particularly prone to complex ecological interactions resulting from nutrient inputs from both the land and sea. Nutrient inputs to coastal systems often spur ulvoid macroalgal blooms, with negative consequences for seagrasses, primarily through shading, as well as through changes in local biogeochemistry.

Ocean acidification research in the 'post-genomic' era: Roadmaps from the purple sea urchin Strongylocentrotus purpuratus.

Advances in nucleic acid sequencing technology are removing obstacles that historically prevented use of genomics within ocean change biology. As one of the first marine calcifiers to have its genome sequenced, purple sea urchins (Strongylocentrotus purpuratus) have been the subject of early research exploring genomic responses to ocean acidification, work that points to future experiments and illustrates the value of expanding genomic resources to other marine organisms in this new 'post-genomic' era. This review presents case studies of S.

Intensification and spatial homogenization of coastal upwelling under climate change.

The timing and strength of wind-driven coastal upwelling along the eastern margins of major ocean basins regulate the productivity of critical fisheries and marine ecosystems by bringing deep and nutrient-rich waters to the sunlit surface, where photosynthesis can occur. How coastal upwelling regimes might change in a warming climate is therefore a question of vital importance. Although enhanced land-ocean differential heating due to greenhouse warming has been proposed to intensify coastal upwelling by strengthening alongshore winds, analyses of observations and previous climate models have provided little consensus on historical and projected trends in coastal upwelling.

Designing effective reserve networks for nonequilibrium metacommunities.

The proliferation of efficient fishing practices has promoted the depletion of commercial stocks around the world and caused significant collateral damage to marine habitats. Recent empirical studies have shown that marine reserves can play an important role in reversing these effects. Equilibrium metapopulation models predict that networks of marine reserves can provide similar benefits so long as individual reserves are sufficiently large to achieve self-sustainability, or spaced based on the extent of dispersal of the target species in order to maintain connectivity between neighboring reserves.

Transcriptomic responses to ocean acidification in larval sea urchins from a naturally variable pH environment.

Some marine ecosystems already experience natural declines in pH approximating those predicted with future anthropogenic ocean acidification (OA), the decline in seawater pH caused by the absorption of atmospheric CO2 . The molecular mechanisms that allow organisms to inhabit these low pH environments, particularly those building calcium carbonate skeletons, are unknown. Also uncertain is whether an enhanced capacity to cope with present day pH variation will confer resistance to future OA.

Transcriptome profiles link environmental variation and physiological response of Mytilus californianus between Pacific tides.

SUMMARY: The marine intertidal zone is characterized by large variation in temperature, pH, dissolved oxygen and the supply of nutrients and food on seasonal and daily time scales. These oceanic fluctuations drive of ecological processes such as recruitment, competition and consumer-prey interactions largely via physiological mehcanisms. Thus, to understand coastal ecosystem dynamics and responses to climate change, it is crucial to understand these mechanisms.

More than a meal… integrating non-feeding interactions into food webs.

Organisms eating each other are only one of many types of well documented and important interactions among species. Other such types include habitat modification, predator interference and facilitation. However, ecological network research has been typically limited to either pure food webs or to networks of only a few (<3) interaction types.