We present a Bayesian hierarchical model to estimate the abundance and the biomass of brown trout (Salmo trutta fario) by using removal sampling and biometric data collected at several stream sections. The model accounts for (i) variability of the abundance with fish length (as a distribution mixture), (ii) spatial variability of the abundance, (iii) variability of the catchability with fish le...

—Absence of a species when it is not observed from a given area is ensured only when the probability of observation, when present, is 1. This condition is rarely satisfied in surveys of animals in natural environments, particularly with elusive targets such as fish. Detectability (probability of species encounter) is a function of probability of individual capture, which varies widely with samp...

1. Background .......................................................................................................................................... 1 2. General topics....................................................................................................................................... 3 2.1. Data issues .........................................................................

Together with life-history and underlying physiology, the behavioural variability among fish is one of the three main trait axes that determines the vulnerability to fishing. However, there are only a few studies that have systematically investigated the strength and direction of selection acting on behavioural traits. Using in situ fish behaviour revealed by telemetry techniques as input, we d...

BACKGROUND Nearly all HIV infections in children worldwide are acquired through mother-to-child transmission (MTCT) during pregnancy, labour, delivery or breastfeeding. The objective of our study was to estimate the number and rate of new HIV diagnoses in children less than 13 years of age in mainland France from 2003-2006. METHODS We performed a capture-recapture analysis based on three sour...

The Sardinella aurita fishery off northeastern Venezuela, region of seasonal wind-driven coastal-upwelling, accounts for 90% of the Caribbean Sea small pelagic catch. This law-protected artisanal fishery takes place up to ~10 km offshore. The spatial distribution, number of schools, and biomass of S. aurita were studied using eight hydro-acoustic surveys (1995-1998). The study included the anal...

In a letter to Nature, Myers and Worm present, for a wide range of oceanic ecosystems, an analysis of catches per unit of effort (CPUE) data, leading them to the conclusion of “a rapid worldwide depletion of predatory fish communities”: After a sharp initial reduction, CPUE appears stable since more than twenty years at a level of about 10% of their initial value. Such a result makes quite evid...