J. Howard Choat

J. Howard Choat
James Cook University

About

200
Publications
76,151
Reads
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13,396
Citations
Citations since 2016
37 Research Items
5439 Citations
20162017201820192020202120220200400600800
20162017201820192020202120220200400600800
20162017201820192020202120220200400600800
20162017201820192020202120220200400600800
Introduction
Skills and Expertise

Publications

Publications (200)
Article
Full-text available
Patterns of reproductive ontogeny in four species of coral reef wrasses (F: Labridae) Hemigymnus melapterus, H. fasciatus, Cheilinus fasciatus, and Oxycheilinus digramma were investigated. Populations of each species were sampled from two island groups of the central Great Barrier Reef (GBR), Australia and from coral reefs in the central Philippine...
Article
Full-text available
Genetic structure within marine species may be driven by local adaptation to their environment, or alternatively by historical processes, such as geographic isolation. The gulfs and seas bordering the Arabian Peninsula offer an ideal setting to examine connectivity patterns in coral reef fishes with respect to environmental gradients and vicariance...
Article
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Globally, groupers (Epinephelidae) that form fish spawning aggregations (FSAs) are highly vulnerable to overfishing and often require site-specific approaches to management. Over 5-years (2009–2013), we conducted underwater visual censuses (UVC) at a well-known spawning site at Njari Island, Gizo, Western Province, Solomon Islands, that supports ag...
Article
Full-text available
Biological feedbacks generated through patterns of disturbance are vital for sustaining ecosystem states. Recent ocean warming and thermal anomalies have caused pantropical episodes of coral bleaching, which has led to widespread coral mortality and a range of subsequent effects on coral reef communities. Although the response of many reef-associat...
Article
Full-text available
1. Variation in life‐history characteristics is evident within and across animal populations. Such variation is mediated by environmental gradients and reflects metabolic constraints or trade‐offs that enhance reproductive outputs. While generalizations of life‐history relationships across species provide a framework for predicting vulnerability to...
Article
Herbivorous reef fishes are considered to have difficulty digesting plant material at extratropical temperatures and are thus largely restricted to tropical waters where they are thought to have evolved. However, the herbivorous Kyphosidae, with both temperate and tropical species, provides an ideal opportunity to test this view. Previous studies h...
Article
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The structure and dynamics of coral reef environments vary across a range of spatial scales, with patterns of associated faunal assemblages often reflecting this variability. However, delineating drivers of biological variability in such complex environments has proved challenging. Here, we investigated the assemblage structure and diversity of par...
Article
Epulopiscium sp. type B (Lachnospiraceae) is an exceptionally large, highly polyploid, intestinal symbiont of the coral reef dwelling surgeonfish Naso tonganus. These obligate anaerobes do not form mature endospores and reproduce solely through the production of multiple intracellular offspring. This likely makes them dependent on immediate transfe...
Article
Full-text available
Reef configuration and hydrodynamics were identified as the principle physical drivers behind coral reef fish aggregations on a mid-shelf patch reef in the northern section of the Great Barrier Reef (-16.845°, 146.23°). The study was carried out over a six-year period at a large reef pass on the oceanic margin of the northern Great Barrier Reef. Ov...
Data
Caesionidae abundance data at Moore Reef fish aggregation site. (CSV)
Data
Describes the source of environmental conditions collated with the fish composition and abundance data. The data was collected between 1 February 2006 to 29 November 2012, except the Secchi data which commenced 24 June 2007. Data collection for some variables marked with an * was collected sporadically and not continuous due to repository limitatio...
Data
Species list of Moore Reef fish aggregation site. This list 110 fish (>20cm) from 21 families (in bold) and yes (Y) or no (N) whether these species form aggregations at the Moore reef fish aggregation site (with notes on foraging and reproductive behaviour of aggregating species or if unknown). (DOCX)
Data
Moore Reef fish abundance and environmental variable data. (CSV)
Article
Full-text available
The bumphead parrotfish (Bolbometopon muricatum) is an iconic coral reef species of commercial, subsistence, and cultural value that has faced severe declines across the Indo-Pacific. In this study, we summarized the age-based biological characteristics of B. muricatum based on comprehensive surveys of a small-scale but high-yield fishery in Solomo...
Article
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Background Understanding the factors shaping population genetic structure is important for evolutionary considerations as well as for management and conservation. While studies have revealed the importance of palaeogeographic changes in shaping phylogeographic patterns in multiple marine fauna, the role of reproductive behaviour is rarely considere...
Article
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For tropical marine species, hotspots of endemism occur in peripheral areas furthest from the center of diversity, but the evolutionary processes that lead to their origin remain elusive. We test several hypotheses related to the evolution of peripheral endemics by sequencing ultraconserved element (UCE) loci to produce a genome-scale phylogeny of...
Article
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The humphead wrasse (Cheilinus undulatus) and bumphead parrotfish (Bolbometopon muricatum) are two of the largest, most iconic fishes of Indo‐Pacific coral reefs. Both species form prized components of subsistence and commercial fisheries and are vulnerable to overfishing. C. undulatus is listed as Endangered and B. muricatum as Vulnerable on the I...
Article
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We quantify the relative importance of multi‐scale drivers of reef fish assemblage structure on isolated coral reefs at the intersection of the Indian and Indo‐Pacific biogeographical provinces. Large (>30 cm), functionally‐important and commonly targeted species of fish, were surveyed on the outer reef crest/front at 38 coral reef sites spread acr...
Article
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Ectotherms exhibit considerable plasticity in their life-history traits. This plasticity can reflect variability in environmental and social factors, but the causes of observed patterns are often obscured with increasing spatial scales. We surveyed dichromatic parrotfishes across the northern Great Barrier Reef to examine variation in body size dis...
Article
Marine reserves exhibit increases in targeted fish species, but long-term effects on biodiversity are poorly understood. Factors other than reserve status may affect decadal changes, including environmental change. We examined the fish fauna at the iconic Poor Knights Islands over 4 decades (1974-2016) before and after implementation of a no-take m...
Article
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The Arabian Sea is a heterogeneous region with high coral cover and warm stable conditions at the western end (Djibouti), in contrast to sparse coral cover, cooler temperatures, and upwelling at the eastern end (southern Oman). We tested for barriers to dispersal across this region (including the Gulf of Aden and Gulf of Oman), using mitochondrial...
Article
The loss of nursery habitats is widely believed to contribute disproportionally to declines in abundance and productivity of fish populations. However, it has been difficult to establish links between the processes threatening nurseries and changes in population demography. Here we show that juvenile bumphead parrotfish (Bolbometopon muricatum), an...
Article
Full-text available
Coral reef ecosystems are remarkable for their high productivity in nutrient-poor waters. A high proportion of primary production is consumed by the dominant herbivore assemblage, teleost fishes, many of which are the product of recent and rapid diversification. Our review and synthesis of the trophodynamics of herbivorous reef fishes suggests that...
Article
Full-text available
Bolbometopon muricatum, the largest species of parrotfish, is a functionally important species that is characterised by the formation of aggregations for foraging, reproductive, and sleeping behaviours. Aggregations are restricted to shallow reef habitats, the locations of which are often known to local fishers. Bolbometopon muricatum fisheries are...
Article
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Increased temperatures are associated with reduced body sizes, life spans, and reproductive outputs in shallow water marine fishes, reflecting the pervasive effects of temperature on metabolic rates in ectotherms. Herbivorous fishes have been seen as an exception to this trend, based on the hypothesis that physiological and demographic processes in...
Article
The Red Sea is characterised by a unique fauna and historical periods of desiccation, hypersalinity and intermittent isolation. The origin and contemporary composition of reef-associated taxa in this region can illuminate biogeographical principles about vicariance and the establishment (or local extirpation) of existing species. Here we aim to: (1...
Article
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Aim The geological and palaeo-climatic forces that produced the unique biodiversity in the Red Sea are a subject of vigorous debate. Here, we review evidence for and against the hypotheses that: (1) Red Sea fauna was extirpated during glacial cycles of the Pleistocene and (2) coral reef fauna found refuge within or just outside the Red Sea during l...
Article
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Refinements to the methodology of bomb radiocarbon dating made it possible to validate age estimates of the humphead wrasse (Cheilinus undulatus) and bumphead parrotfish (Bolbometopon muricatum). Age for these species has been estimated from presumed annual growth zones in otoliths at similar to 30 and similar to 40 years respectively. The validity...
Article
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Christmas Island (Indian Ocean) is an oceanic high island that is situated 300 km southwest of Java, Indonesia. From 2010 to 2014, the fish community of Christmas Island was surveyed using underwater visual surveys for shallow water (0–60 m) fishes, and line fishing (bottom fishing and trolling) for deepwater (60–300 m) and pelagic fishes. Forty-se...
Article
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The Cocos (Keeling) Islands comprise the most isolated oceanic atoll in the tropical Indian Ocean and are situated 1000 km south-west of Indonesia. The remoteness of the islands has shaped the composition of marine communities but also limited scientific research. This study summarises field research on the marine fishes of the Cocos (Keeling) Isla...
Article
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Newly recruited Ctenochaetus striatus were monitored over a 16-month period in American Samoa, 2002-2003. During this period, a mass recruitment of age-0 C. striatus occurred in March 2002 with numbers reaching 22.9 recruits m(-2). This program provided an invaluable opportunity to (1) analyze the dynamics of a mass recruitment episode and to asses...
Article
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Territories of grazing fishes in the family Pomacentridae have been documented to cover a sub-stantial proportion of shallow, exposed coral reef fronts, and these fishes can have profound effects on benthic community composition, including the recruitment and post-settlement survival of scleractinian corals. However, current studies of territorial...
Article
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Parrotfishes are considered to have a major influence on coral reef ecosystems through grazing the benthic biota and are also primary fishery targets in the Indo-Pacific. Consequently, the impact of human exploitation on parrotfish communities is of prime interest. As anthropogenic and environmental factors interact across spatial scales, sampling...
Article
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Microbial community structure on coral reefs is strongly influenced by coral-algae interactions; however, the extent to which this influence is mediated by fishes is unknown. By excluding fleshy macroalgae, cultivating palatable filamentous algae and engaging in frequent aggression to protect resources, territorial damselfish (f. Pomacentridae), su...
Article
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A scarcity of life-history data currently exists for many exploited coral reef fishes, hindering our ability to interpret fishery dynamics and develop sound conservation policies. In particular, parrotfishes (Family Labridae) represent a ubiquitous and ecologically important group that is increasingly prevalent in commercial and artisanal fisheries...
Article
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High-throughput sequencing approaches have enabled characterizations of the community composition of numerous gut microbial communitiess, which in turn has enhanced interest in their diversity and functional relationships in different groups of vertebrates. Although fishes represent the greatest taxonomic and ecological diversity of vertebrates, ou...
Article
Full-text available
Fishery-independent sampling was used to determine growth patterns, life span, mortality rates and timing of maturation and sex change in 12 common parrotfishes (Labridae: tribe Scarinae) from five genera (Calotomus, Cetoscarus, Chlorurus, Hipposcarus and Scarus) in Micronesia. Interspecific variation in life-history traits was explored using multi...
Article
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In ectotherms, growth rate, body size, and maturation rate co-vary with temperature, with the direction and magnitude of variation predicted by the Temperature-Size Rule (TSR). Nutritional quality or availability of food, however, may vary over latitudinal gradients, resulting in ambiguous effects on body size and maturation rate. The Temperature-C...
Article
Aim The Red Sea is a biodiversity hotspot characterized by a unique marine fauna and high endemism. This sea began forming c. 24 million years ago with the separation of the African and Arabian plates, and has been characterized by periods of desiccation, hypersalinity and intermittent connection to the Indian Ocean. We aim to evaluate the impact o...
Article
Full-text available
Groupers are a valuable fishery resource of reef ecosystems and are among those species most vulnerable to fishing pressure because of life history characteristics including longevity, late sexual maturation and aggregation spawning. Despite their economic importance, few grouper fisheries are regularly monitored or managed at the species level, an...
Article
Full-text available
Phylogenetic reconstruction of the evolutionary relationships among 61 of the 70 species of the parrotfish genera Chlorurus and Scarus (Family Labridae) based on mitochondrial and nuclear gene sequences retrieved 15 well-supported clades with mid Pliocene/Pleistocene diversification. Twenty-two reciprocally monophyletic sisterspecies pairs were ide...
Data
Full-text available
Percentage of coral reef loss and declining reef area for all species of parrotfishes and surgeonfishes (1 = exclusively coral reef dependent, 2 = primarily found in coral reefs, 3 = mixed habitat). (PDF)
Data
Major threats identified for each species of parrotfish and surgeonfish. (PDF)
Data
Full-text available
Complete list of species, Red List Category and associated information on life history, dietary classification and presence in marine reserves. (PDF)
Article
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Parrotfishes and surgeonfishes perform important functional roles in the dynamics of coral reef systems. This is a consequence of their varied feeding behaviors ranging from targeted consumption of living plant material (primarily surgeonfishes) to feeding on detrital aggregates that are either scraped from the reef surface or excavated from the de...
Article
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Many species demonstrate variation in life history attributes in response to gradients in environmental conditions. For fishes, major drivers of life history variation are changes in temperature and food availability. This study examined large-scale variation in the demography of four species of butterflyfishes (Chaetodon citrinellus, Chaetodon lun...
Article
Full-text available
Phylogenetic reconstruction of the evolutionary relationships among 61 of the 70 species of the parrotfish genera Chlorurus and Scarus (Family Labridae) based on mitochondrial and nuclear gene sequences retrieved 15 well-supported clades with mid Pliocene/Pleistocene diversification. Twenty-two reciprocally monophyletic sister species pairs were id...
Chapter
Full-text available
Because the bluehead wrasse mates daily in large aggregations, is not heavily exploited and is easily manipulated, we can answer some questions about spawning aggregations that are very diffi cult to answer in larger, less frequently mating fi shes. For the bluehead wrasse, at least, we know that the sites of spawning aggregations are determined by...