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Community structure and function in ecosystems are dependent on top-down and bottom-up factors, which vary across local, regional, and temporal scales. In estuaries of the U.S. Pacific Northwest coast, eelgrass (Zostera marina) ecosystems are exposed to latitudinally varying oceanographic inputs in the form of ocean upwelling. Previous research suggests that ocean upwelling is critical to eelgrass and ulvoid macroalgae abundance, but the degree to which secondary producers are controlled by processes at regional vs. local scales is unknown. Here, we consider the relationships among primary producers (eelgrass, ulvoid macroalgae, and epiphytic microalgae), epifaunal mesograzers, and mesopredator fish within and across three Oregon, U.S.A., estuaries during a spring–summer season to examine the role of multiple scales in structuring these communities. Our objectives were to determine the relative importance of local and regional scales in organizing eelgrass communities and the potential of regional oceanography and trophic interactions in regulating patterns of primary producers in this system. We found that regional and seasonal patterns strongly influenced eelgrass community structure, providing support for the hypothesis that regional bottom-up forcing predominantly controls these assemblages. Additionally, local effects were important to the patterns of primary producers, mesograzers, and mesopredator fish at specific sites, suggesting limited top–down control. Regarding management and conservation, the implications of our results are that in these highly productive systems, the potential for consumers to moderate the effects of eutrophication may be limited., This work was funded by the Department of Fisheries and Wildlife (OSU) to F. Tomas. Funding was partially provided by Oregon Sea Grant under award number NA14OAR4170064 (project number R/ECO‐34) from the National Oceanic and Atmospheric Administration's National Sea Grant College Program, U.S. Department of Commerce, and by appropriations made by the Oregon State Legislature. Support was also provided by the José Castillejo Program to FT (CAS14/00177).

This paper evaluated the efficiency of beach hatcheries as a conservation tool for threatened sea turtle clutches. During six nesting seasons (2013 to 2018), several thousand high-risk clutches from loggerhead turtles (Caretta caretta) were relocated to a hatchery constructed on the same beach, within the Sea Turtle Natural Reserve (STNR, Boa Vista Island, Cabo Verde). Some parameters like hatching success; incubation period, hatchlings’ morphology and their behavioral response were compared to in-situ clutches. •Our findings confirmed that the in-situ nests within the STNR had extremely high egg mortality that was usually over 70 %. Mean hatching success of clutches relocated to hatcheries was significantly higher than in- situ clutches with mean values between 70 to 85 % ( p < 0.0 0 01). •No significant differences were observed in the incubation period ( p = 0.786) and morphology of hatchlings (all p > 0.05) between relocated and in-situ clutches. •This study provided a detailed method and recommendations for sea turtle clutches relocation to the hatchery, that can be beneficial for endangered sea turtle population specially where hatching success is very low

Much progress has been made in the past few decades in understanding the sources, transport, fate, and biological effects of contaminants of emerging concern (CECs) in aquatic ecosystems. Despite these advancements, significant obstacles still prevent comprehensive assessments of the environmental risks associated with the presence of CECs. Many of these obstacles center around the extrapolation of effects of single chemicals observed in the laboratory or effects found in individual organisms or species in the field to impacts of multiple stressors on aquatic food webs. In the present review, we identify 5 challenges that must be addressed to promote studies of CECs from singular exposure events to multispecies aquatic food web interactions. There needs to be: 1) more detailed information on the complexity of mixtures of CECs in the aquatic environment, 2) a greater understanding of the sublethal effects of CECs on a wide range of aquatic organisms, 3) an ascertaining of the biological consequences of variable duration CEC exposures within and across generations in aquatic species, 4) a linkage of multiple stressors with CEC exposure in aquatic systems, and 5) a documenting of the trophic consequences of CEC exposure across aquatic food webs. We examine the current literature to show how these challenges can be addressed to fill knowledge gaps. Environ Toxicol Chem 2019;38:46–60, Funding for the present review was provided by the US Geological Survey Oregon Water Science Center, and the US Geological Survey Toxic Substances Hydrology Program. H.L. Schoenfuss received support from the Great Lakes Restoration Initiative through the US Fish and Wildlife Service CEC team, as well as additional funding from a National Science Foundation grant (CBET 1336062).

Knowledge of the mechanisms influencing phenology can provide insights into the adaptability of species to climate change. Here, we investigated the factors influencing multidecadal trends in the nesting phenology of the leatherback turtle Dermochelys coriacea at Playa Grande, Costa Rica, in the eastern Pacific Ocean and at Sandy Point, US Virgin Islands, in the western Atlantic Ocean. Between 1993 and 2013, the median nesting date (MND) at Playa Grande occurred later, at a rate of ~0.3 d yr-1. In contrast, between 1982 and 2010, the MND at Sandy Point occurred earlier, at a rate of ~0.17 d yr-1. The opposing trends in the MND of each population were not explained by variation in the multivariate El Niño-Southern Oscillation index, North Atlantic Oscillation index, or Atlantic Multidecadal Oscillation index; however, the MND at Playa Grande was significantly correlated with nesting population size. We propose that changes in demography, linked to the population decline at Playa Grande, and the population recovery at Sandy Point may explain the contrasting trends in MNDs. If the observed trends in MND continue into the future, the nesting season at Playa Grande will coincide with increasingly adverse conditions for hatching success, exacerbating the already detrimental effects of climate change. Alternatively, shifts in the nesting phenology may make the Atlantic populations more resilient to climate change. Our findings highlight the increasing need for conservation efforts for eastern Pacific leatherback turtles to consider climate change mitigation practices, Funding for the project at Playa Grande was provided by the Earthwatch Institute, The Betz Chair Endowment of Drexel University, The Schrey Chair Endowment of Indiana University-Purdue University Fort Wayne, and The Leatherback Trust. Funding for the project at Sandy Point was provided by the USFWS — Division of Refuges, the National Marine Fisheries Service — Southwest Science Center, West Indies Marine Animal Research and Conservation Service, USFWS Section 6 appropriations administered through the Virgin Islands Department of Planning and Natural Resources, and the EarthWatch Institute

Santidrián Tomillo, Pilar et al., The most recent climate change projections show a global increase in temperatures along with precipitation changes throughout the 21 century. However, regional projections do not always match global projections and species with global distributions may exhibit varying regional susceptibility to climate change. Here we show the effect of local climatic conditions on the hatchling output of leatherback turtles (Dermochelys coriacea) at four nesting sites encompassing the Pacific, Atlantic and Indian Oceans. We found a heterogeneous effect of climate. Hatchling output increased with long-term precipitation in areas with dry climatic conditions (Playa Grande, Pacific Ocean and Sandy Point, Caribbean Sea), but the effect varied in areas where precipitation was high (Pacuare, Caribbean Sea) and was not detected at the temperate site (Maputaland, Indian Ocean). High air temperature reduced hatchling output only at the area experiencing seasonal droughts (Playa Grande). Climatic projections showed a drastic increase in air temperature and a mild decrease in precipitation at all sites by 2100. The most unfavorable conditions were projected for Sandy Point where hatching success has already declined over time along with precipitation levels. The heterogeneous effect of climate may lead to local extinctions of leatherback turtles in some areas but survival in others by 2100., Funding for the study was provided by a Marie Curie International Incoming Fellowship within the 7th European Community Framework Programme. Specific funding for each site was provided by the Earthwatch Institute, the Betz Chair of Environmental Science at Drexel University, the Schrey Chair of Biology at IPFW and The Leatherback Trust (Playa Grande), the US Fish and Wildlife Service (USFWS) (Sandy Point), the Endangered Wildlife Trust (Pacuare) and NRF/Thuthuka and NMMU Postgraduate Research Scholarship (Maputaland)

[EN]: Monitoring bird populations is essential for the proper management of natural areas, since birds serve as indicator species to assess the conservation status of ecosystems. Therefore, it is important to estimate population sizes using methods of the highest possible accuracy and reliability. In this study, the populations of three marsh-dwelling passerines were sampled in the Tablas de Daimiel National Park (central Spain) during the breeding season, using a double independent observer technique. Data analysis was performed using a hierarchical Bayesian model with covariates that can simultaneously determine the population size and detectability, as well as factors that significantly affect both parameters. The presence of the two most threatened species, the reed bunting Emberiza schoeniclus witherbyi and the moustached warbler Acrocephalus melanopogon, was significantly and positively related to the coverage of fen sedge Cladium mariscus, an indicator species for waters of high quality and low fluctuation in depth. The bearded parrotbill Panurus biarmicus was the most generalist species with no positive association with any of the studied variables. The moustached warbler was more readily detectable until the beginning of May and early in the morning. [ES]: El seguimiento y evaluación de las poblaciones de aves constituye una herramienta fundamental para la adecuada gestión de espacios naturales, dado su carácter indicativo del estado de conservación de los ecosistemas. Por ello, resulta importante aplicar métodos que permitan la mayor precisión y fiabilidad para obtener tamaños de población. En este trabajo se muestreó la población de tres paseriformes palustres en el Parque Nacional de Las Tablas de Daimiel (centro de España) en época reproductora, a través de la técnica de doble observador independiente. Para el tratamiento de los datos se utilizó un modelo jerárquico bayesiano con covariables que permite determinar simultáneamente el tamaño poblacional y la detectabilidad, así como los factores que afectan significativamente a ambos parámetros. La presencia de las dos especies más amenazadas, el escribano palustre iberoriental Emberiza schoeniclus witherbyi y el carricerín real Acrocephalus melanopogon estuvo relacionada significativa y positivamente con el grado de cobertura de masiega Cladium mariscus, especie indicadora de una elevada calidad del agua y un régimen hídrico relativamente poco fluctuante. El bigotudo Panurus biarmicusresultó el más generalista y no seleccionó significativamente ninguna de las variables estudiadas. El carricerín real resultó más fácilmente detectable hasta primeros de mayo y a primera hora de la mañana. To Laura Phillips, Tammy Wilson, Fagan Johnson (USNPS) and Bill Thompson (USFWS) for their help with data from original R+BUGS code.

Understanding how gene flow shapes contemporary population structure requires the explicit consideration of landscape composition and configuration. New landscape genetic approaches allow us to link such heterogeneity to gene flow within and among populations. However, the attribution of cause is difficult when landscape features are spatially correlated, or when genetic patterns reflect past events. We use spatial Bayesian clustering and landscape resistance analysis to identify the landscape features that influence gene flow across two regional populations of the eastern massasauga rattlesnake, Sistrurus c. catenatus. Based on spatially explicit simulations, we inferred how habitat distribution modulates gene flow and attempted to disentangle the effects of spatially confounded landscape features. We found genetic clustering across one regional landscape but not the other, and also local differences in the effect of landscape on gene flow. Beyond the effects of isolation-by-distance, water bodies appear to underlie genetic differentiation among individuals in one regional population. Significant effects of roads were additionally detected locally, but these effects are possibly confounded with the signal of water bodies. In contrast, we found no signal of isolation-by-distance or landscape effects on genetic structure in the other regional population. Our simulations imply that these local differences have arisen as a result of differences in population density or tendencies for juvenile rather than adult dispersal. Importantly, our simulations also demonstrate that the ability to detect the consequences of contemporary anthropogenic landscape features (e.g. roads) on gene flow may be compromised when long-standing natural features (e.g. water bodies) co-exist on the landscape., This work was supported by an NSERC Discovery Grant (SCL), a postgraduate scholarship (MFD), Sigma-Xi Grants-in-Aid-of-Research (MFD), a National Geographic Young Explorers Grant (MFD) and Parks Canada. We gratefully acknowledge the support of WWF-Canada, Environment Canada and the Ontario Ministry of Natural Resources through the Endangered Species Recovery Fund and Species at Risk Research Fund for Ontario.

[EN]: Monitoring bird populations is essential for the proper management of natural areas, since birds serve as indicator species to assess the conservation status of ecosystems. Therefore, it is important to estimate population sizes using methods of the highest possible accuracy and reliability. In this study, the populations of three marsh-dwelling passerines were sampled in the Tablas de Daimiel National Park (central Spain) during the breeding season, using a double independent observer technique. Data analysis was performed using a hierarchical Bayesian model with covariates that can simultaneously determine the population size and detectability, as well as factors that significantly affect both parameters. The presence of the two most threatened species, the reed bunting Emberiza schoeniclus witherbyi and the moustached warbler Acrocephalus melanopogon, was significantly and positively related to the coverage of fen sedge Cladium mariscus, an indicator species for waters of high quality and low fluctuation in depth. The bearded parrotbill Panurus biarmicus was the most generalist species with no positive association with any of the studied variables. The moustached warbler was more readily detectable until the beginning of May and early in the morning., [ES]: El seguimiento y evaluación de las poblaciones de aves constituye una herramienta fundamental para la adecuada gestión de espacios naturales, dado su carácter indicativo del estado de conservación de los ecosistemas. Por ello, resulta importante aplicar métodos que permitan la mayor precisión y fiabilidad para obtener tamaños de población. En este trabajo se muestreó la población de tres paseriformes palustres en el Parque Nacional de Las Tablas de Daimiel (centro de España) en época reproductora, a través de la técnica de doble observador independiente. Para el tratamiento de los datos se utilizó un modelo jerárquico bayesiano con covariables que permite determinar simultáneamente el tamaño poblacional y la detectabilidad, así como los factores que afectan significativamente a ambos parámetros. La presencia de las dos especies más amenazadas, el escribano palustre iberoriental Emberiza schoeniclus witherbyi y el carricerín real Acrocephalus melanopogon estuvo relacionada significativa y positivamente con el grado de cobertura de masiega Cladium mariscus, especie indicadora de una elevada calidad del agua y un régimen hídrico relativamente poco fluctuante. El bigotudo Panurus biarmicusresultó el más generalista y no seleccionó significativamente ninguna de las variables estudiadas. El carricerín real resultó más fácilmente detectable hasta primeros de mayo y a primera hora de la mañana., To Laura Phillips, Tammy Wilson, Fagan Johnson (USNPS) and Bill Thompson (USFWS) for their help with data from original R+BUGS code.