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Assessments of the biodiversity and structure of coral reef fish communities are often plagued by inadequate sampling and biases inherent in commonly used Underwater Visual Census (UVC) methods. Of these biases, heterogeneity in the detectability of reef-fish species is often ignored, even though it may have substantial effects on biodiversity estimates. Using highly replicated UVC sampling of all fish species at 4 sites in Tanzania, East Africa, we show that detectability varies greatly across species and is affected by traits such as body size and schooling behaviour, and that detectability of reef fishes can be readily accounted for by the application of Capture-MarkRecapture (CMR) models. Based on our results, we recommend that approximately 24 point counts are necessary to assess full reef-fish species richness at sites in the Western Indian Ocean. KEY WORDS: Mark-recapture · Underwater Visual Census · Coral reefs · Bayesian · Marine reserve Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 367: [249][250][251][252][253][254][255][256][257][258][259][260] 2008 Mapstone 1997), species (Kulbicki & Sarramégna 1999), random instantaneous movement (McClanahan et al. 2007), and the choice of method itself (Watson & Quinn 1997, Kulbicki & Sarramégna 1999, Samoilys & Carlos 2000. Most of these problems are dealt with through technique standardisation and by the assumption that biases are consistent among studies (Ackerman & Bellwood 2000). However, unknown systematic heterogeneity can seriously bias estimates of species richness, directly affecting the ability to make accurate assessments of biodiversity.Detectability is defined as the probability of observing a particular species during a given sampling occasion conditional on its presence at that location (Boulinier et al. 1998). UVC based studies routinely assume that detectability = 1 across all species but it can vary substantially among reef fishes due to physical, behavioural, or life-history characteristics. For example, lethrinids have been shown to avoid divers (Kulbicki 1998, Kulbicki & Sarramégna 1999, leading to a frequent lack of agreement between UVC and fishing data in tropical fisheries (Jennings & Polunin 1995, Kulbicki 1998. Cryptic morphology or behaviour can also affect detectability, as more than 90% of cryptic species may be undetected by UVC methods (Willis 2001); the recognition of low detectability has led to surveys that target only a subset of the community that excludes the least detectable species. There is also a strong, positive relationship between detectability and abundance (Dorazio & Royle 2005) that can generate substantial heterogeneity among surveys. Compounding this issue is the fact that surveys are routinely conducted using relatively low numbers of replicates. Not accounting for detection, heterogeneity may be acceptable if the bias is small relative to the size of the target community but it is essential to estimate both the magnitude of biases present and the ap...

SummaryObjectiveThere are conflicting data regarding the association between body mass index (BMI) and health‐related quality of life (HRQoL), especially among certain population subgroups and for mental and physical health domains.MethodsThis study analysed the relationship between BMI and HRQoL (Patient‐Reported Outcomes Measurement Information System mental and physical health scales) using ordinary least squares regression. Each model allowed for the possibility of a non‐linear relationship between BMI and the outcome, adjusting for age, gender, comorbidities, diet and physical activity.ResultsA total of 10,133 respondents were predominantly female (71.7%), White (84.1%), median age of 52.1 years (interquartile range 37.2–63.3) and median BMI of 27.9 (interquartile range 24.0–33.2). In adjusted models, BMI was significantly associated with physical and mental HRQoL (p < 0.001). For physical HRQoL, there was a significant interaction with age (p = 0.02). For mental HRQoL, there was a significant interaction with sex (p = 0.0004) but not age (p = 0.7).ConclusionsThis study demonstrates a non‐linear association of variable clinical relevance between BMI and HRQoL after adjusting for demographic factors and comorbidities. The relationship between BMI and HRQoL is nuanced and impacted by gender and age. These findings challenge the idea of obesity as a main driver of reduced HRQoL, particularly among women and with respect to mental HRQoL.

Crown-of-thorns starfish (CoTS; Acanthaster spp.) are an outbreaking pest among many Indo-Pacific coral reefs that cause substantial ecological and economic damage. Despite ongoing CoTS research, there remain critical gaps in observing CoTS populations and accurately estimating their numbers, greatly limiting understanding of the causes and sources of CoTS outbreaks. Here we address two of these gaps by (1) estimating the detectability of adult CoTS on typical underwater visual count (UVC) surveys using covariates and (2) inter-calibrating multiple data sources to estimate CoTS densities within the Cairns sector of the Great Barrier Reef (GBR). We find that, on average, CoTS detectability is high at 0.82 [0.77, 0.87] (median highest posterior density (HPD) and [95% uncertainty intervals]), with CoTS disc width having the greatest influence on detection. Integrating this information with coincident surveys from alternative sampling programs, we estimate CoTS densities in the Cairns sector of the GBR averaged 44 [41, 48] adults per hectare in 2014.

This prospective acute gastroenteritis (AGE) surveillance was conducted in the inpatient and emergency room settings at a referral pediatric hospital to determine the prevalence of diarrheagenic Escherichia coli (DEC) in children<12 years of age with AGE in Davidson County, Tennessee. Subjects 15 days to 11 years of age, who presented with diarrhea and/or vomiting, were enrolled. Stool specimens were processed for detection of DEC using multiplex polymerase chain reaction. From December 1, 2011, to June 30, 2012, a total of 79 (38%) out of 206 stool specimens from children with AGE tested positive for E. coli. A total of 12 (5.8%) out of 206 stool specimens from children with AGE were positive for a DEC. Eight (67%) out of these 12 were positive for enteropathogenic E. coli, and the remaining 4 were positive for enteroaggregative E. coli. DEC clinical isolates clustered with known E. coli enteropathogens according to multilocus sequencing typing.