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Phylogeography of reef fishes across the line Islands: uncovering population structure in a data deficient regionNARA Subscribed
Despite decades of study, it remains difficult to predict the genetic structure of populations of marine species, even with extensive knowledge of the regional oceanography, geography, and the life history of the species. Genetic data provide key insights into population structure that cannot be otherwise inferred. To this end, phylogeographic patterns across the Line Islands were assessed in three unrelated species of reef-as...
Closing the gap between existing large‐area imaging research and marine conservation needsNARA Subscribed
Emerging technology has immense potential to increase the scale and efficiency of marine conservation. One such technology is large‐area imaging (LAI), which relies on structure‐from‐motion photogrammetry to create composite products, including 3‐dimensional (3‐D) environmental models, that are larger in spatial extent than the individual images used to create them. Use of LAI has become widespread in certain fields of marine...
Variability in composition of parrotfish bite scars across space and over time on a central Pacific atollNARA Subscribed
Parrotfishes are conspicuous herbivores, microvores, and detritivores in coral reef ecosystems, and the impacts of their feeding, particularly their capacity to expose reef carbonate, have received much attention. In many cases, parrotfish assemblages have been shown to control algal proliferation and promote the settlement of corals and crustose coralline algae (CCA). In extreme cases, high densities of parrotfishes may negat...
One mechanism giving fleshy algae a competitive advantage over corals during reef degradation is algal-induced and microbially-mediated hypoxia (typically less than 69.5 µmol oxygen L −1 ). During hypoxic conditions oxygen availability becomes insufficient to sustain aerobic respiration in most metazoans. Algae are more tolerant of low oxygen conditions and may outcompete corals weakened by hypoxia. A key question on the ecolo...
Decades of research have revealed relationships between the abundance of coral reef taxa and local conditions, especially at small scales. However, a rigorous test of covariation requires a robust dataset collected across wide environmental or experimental gradients. Here, we surveyed spatial variability in the densities of major coral reef functional groups at 122 sites along a 70 km expanse of the leeward, forereef habitat o...
Post-settlement demographics of reef building corals suggest prolonged recruitment bottlenecksNARA Subscribed
For many organisms, early life stages experience significantly higher rates of mortality relative to adults. However, tracking early life stage individuals through time in natural settings is difficult, limiting our understanding of the duration of these ‘mortality bottlenecks’, and the time required for survivorship to match that of adults. Here, we track a cohort of juvenile corals (1–5 cm maximum diameter) from 12 taxa at a...
Human impacts decouple a fundamental ecological relationship—The positive association between host diversity and parasite diversityNARA Subscribed
Human impacts on ecosystems can decouple the fundamental ecological relationships that create patterns of diversity in free‐living species. Despite the abundance, ubiquity, and ecological importance of parasites, it is unknown whether the same decoupling effects occur for parasitic species. We investigated the influence of fishing on the relationship between host diversity and parasite diversity for parasites of coral reef fis...
On the prevalence and dynamics of inverted trophic pyramids and otherwise top‐heavy communitiesNARA Subscribed
Classically, biomass partitioning across trophic levels was thought to add up to a pyramidal distribution. Numerous exceptions have, however, been noted including complete pyramidal inversions. Elevated levels of biomass top‐heaviness (i.e. high consumer/resource biomass ratios) have been reported from Arctic tundra communities to Brazilian phytotelmata, and in species assemblages as diverse as those dominated by sharks and an...
Porites coral response to an oceanographic and human impact gradient in the Line IslandsNARA Subscribed
Coral bleaching caused by heat stress (warm water) will arguably be the greatest driver of coral reef loss in the coming decades. Understanding how corals have adapted to distinct oceanographic regimes on multiple scales can provide insight into future tolerance and persistence, information critical to directed intervention or targeted protections. The northern Line Islands span a gradient in oceanographic regimes across latit...
Productivity and fishing pressure drive variability in fish parasite assemblages of the Line Islands, equatorial PacificNARA Subscribed
Variability in primary productivity and fishing pressure can shape the abundance, species composition, and diversity of marine life. Though parasites comprise nearly half of marine species, their responses to these important forces remain little explored. We quantified parasite assemblages at two spatial scales, across a gradient in productivity and fishing pressure that spans six coral islands of the Line Islands archipelago...
Linking the green and brown worlds: the prevalence and effect of multichannel feeding in food websNARA Subscribed
Recent advances in food‐web ecology highlight that most real food webs (1) represent an interplay between producer‐ and detritus‐based webs and (2) are governed by consumers which are rampant omnivores; feeding on varied prey across trophic levels and resource channels. A possible avenue to unify these advances comes from models demonstrating that predators feeding on distinctly different channels may stabilize food webs. Empi...
Fishing drives declines in fish parasite diversity and has variable effects on parasite abundanceNARA Subscribed
Despite the ubiquity and ecological importance of parasites, relatively few studies have assessed their response to anthropogenic environmental change. Heuristic models have predicted both increases and decreases in parasite abundance in response to human disturbance, with empirical support for both. However, most studies focus on one or a few selected parasite species. Here, we assess the abundance of parasites of seven speci...
Large birth size does not reduce negative latent effects of harsh environments across life stages in two coral speciesNARA Subscribed
When juveniles must tolerate harsh environments early in life, the disproportionate success of certain phenotypes across multiple early life stages will dramatically influence adult community composition and dynamics. In many species, large offspring have a higher tolerance for stressful environments than do smaller conspecifics (parental effects). However, we have a poor understanding of whether the benefits of increased pare...
Using successional theory to measure marine ecosystem healthNARA Subscribed
Synthesizing mechanisms of density dependence in reef fishes: behavior, habitat configuration, and observational scaleNARA Subscribed
Coral and rocky reef fish populations are widely used as model systems for the experimental exploration of density‐dependent vital rates, but patterns of density‐dependent mortality in these systems are not yet fully understood. In particular, the paradigm for strong, directly density‐dependent (DDD) postsettlement mortality stands in contrast to recent evidence for inversely density‐dependent (IDD) mortality. We review the pr...