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We developed a spatially explicit simulation model of poaching behaviour to quantify the relative influence of the intensity, frequency, and spatial distribution of poaching on metapopulation viability. We integrated our model of poaching with a stochastic, habitat-based, spatially explicit population model, applied it to examine the impact of poaching on northern abalone (Haliotis kamtschatkana) metapopulation dynamics in Barkley Sound, British Columbia, Canada, and quantified model sensitivity to input parameters. While demographic parameters remained important in predicting extinction probabilities for northern abalone, our simulations indicate that the odds of extinction are twice as high when populations are subjected to poaching. Viability was influenced by poaching variables that affect the total number of individuals removed. Of these, poaching mortality was the most influential in predicting metapopulation viability, with each 0.1 increase in mortality rate resulting in 22.6% increase in the odds of extinction. By contrast, the location and spatial correlation of events were less important predictors of viability. When data are limited, simulation models of poaching combined with sensitivity analyses can be useful in informing management strategies and future research directions. Nous avons developpe un modele de simulation spatialement explicite du comportement de braconnage pour quantifier l'influence relative de l'intensite, de la frequence et de la repartition spatiale du braconnage sur la viabilite de metapopulations. Nous avons integre notre modele de braconnage a un modele de population stochastique spatialement explicite base sur l'habitat, l'avons applique pour examiner l'incidence du braconnage (Haliotis kamtschatkana) sur la dynamique de metapopulations d'ormeaux nordiques dans la baie Barkley (Colombie-Britannique, Canada) et avons quantifie la sensibilite du modele aux parametres de depart. Si les parametres demographiques demeurent importants pour la prevision des probabilites de disparition pour l'ormeau nordique, nos simulations indiquent que les chances de disparition sont deux fois plus grandes quand les populations font l'objet de braconnage. La viabilite est influencee par des variables associees au braconnage qui ont une incidence sur le nombre total d'individus retires. De ces variables, la mortalite par braconnage est celle qui influence le plus la prediction de la viabilite de metapopulations, chaque augmentation de 0,1 du taux de mortalite se traduisant par une hausse de 22,6% de la probabilite de disparition. En revanche, l'emplacement et la correlation spatiale des evenements sont des variables moins importantes pour ce qui est de predire la viabilite. Quand les donnees sont limitees, les modeles de simulation du braconnage combines a des analyses de la sensibilite peuvent etre utiles pour eclairer les strategies de gestion et orienter les travaux de recherche futurs. [Traduit par la Redaction], Introduction Considered to be one of the primary threats to biodiversity, overexploitation has led to the decline and disappearance of many species worldwide (Wilcove et al. 1998; Venter et al. [...]

Accurate taxonomy, population demography, and habitat descriptors inform species threat assessments and the design of effective conservation measures. Here we combine published studies with new genetic, morphological and habitat data that were collected from seahorse populations located along the European and North African coastlines to help inform management decisions for European seahorses. This study confirms the presence of only two native seahorse species (Hippocampus guttulatus and H. hippocampus) across Europe, with sporadic occurrence of non-native seahorse species in European waters. For the two native species, our findings demonstrate that highly variable morphological characteristics, such as size and presence or number of cirri, are unreliable for distinguishing species. Both species exhibit sex dimorphism with females being significantly larger. Across its range, H. guttulatus were larger and found at higher densities in cooler waters, and individuals in the Black Sea were significantly smaller than in other populations. H. hippocampus were significantly larger in Senegal. Hippocampus guttulatus tends to have higher density populations than H. hippocampus when they occur sympatrically. Although these species are often associated with seagrass beds, data show both species inhabit a wide variety of shallow habitats and use a mixture of holdfasts. We suggest an international mosaic of protected areas focused on multiple habitat types as the first step to successful assessment, monitoring and conservation management of these Data Deficient species., Author(s): Lucy C. Woodall [sup.1] [sup.2] , Francisco Otero-Ferrer [sup.3] , Miguel Correia [sup.2] [sup.4] , Janelle M. R. Curtis [sup.5] , Neil Garrick-Maidment [sup.6] , Paul W. Shaw [sup.7] [...]

Abstract--The long-snouted seahorse (Hippocampus guttulatus) (Cuvier, 1829), was used to validate the predictive accuracy of three progressively realistic models for estimating the realized annual fecundity of asynchronous, indeterminate, multiple spawners. [...]

Accurate taxonomy, population demography, and habitat descriptors inform species threat assessments and the design of effective conservation measures. Here we combine published studies with new genetic, morphological and habitat data that were collected from seahorse populations located along the European and North African coastlines to help inform management decisions for European seahorses. This study confirms the presence of only two native seahorse species ( Hippocampus guttulatus and H. hippocampus) across Europe, with sporadic occurrence of non-native seahorse species in European waters. For the two native species, our findings demonstrate that highly variable morphological characteristics, such as size and presence or number of cirri, are unreliable for distinguishing species. Both species exhibit sex dimorphism with females being significantly larger. Across its range, H. guttulatus were larger and found at higher densities in cooler waters, and individuals in the Black Sea were significantly smaller than in other populations. H. hippocampus were significantly larger in Senegal. Hippocampus guttulatus tends to have higher density populations than H. hippocampus when they occur sympatrically. Although these species are often associated with seagrass beds, data show both species inhabit a wide variety of shallow habitats and use a mixture of holdfasts. We suggest an international mosaic of protected areas focused on multiple habitat types as the first step to successful assessment, monitoring and conservation management of these Data Deficient species. [ABSTRACT FROM AUTHOR]

- In laboratory and field studies of survival, one of two alternative analytical techniques is often used to estimate survival rates and identify covariates, namely parametric survival analysis or Cormack-Jolly-Seber models. These techniques differ in algorithms and assumptions of the data. They also tend to be used under different circumstances depending on whether the intention is to demonstrate group-specific differences or to predict survival variables. Here, we apply and compare both analytical techniques in a study that couples functional genomics with biotelemetry to ascertain the role of physiological condition on survival of adult sockeye salmon ( Oncorhynchus nerka) migrating in the Fraser River, British Columbia, which builds on the growing concern over the decline in numbers of spawning fish. Herein, we show a high level of quantitative and qualitative agreement between the two analytical methods, with both showing a strong relationship exists between the genomic signature that accounts for the largest source of variance in gene expression among individuals and survival in one of the three populations assessed. This high level of agreement suggests the data and the approaches are generating reliable results. The novel approach used in our study to identify physiological processes associated with reduced fitness in wild populations should be of broad interest to conservation biologists and resource managers as it may help reduce the uncertainty associated with predicting population sizes. [ABSTRACT FROM AUTHOR]