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1.
PLoS Biol ; 22(2): e3002497, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38358955

RESUMEN

Online digital data from media platforms have the potential to complement biodiversity monitoring efforts. We propose a strategy for integrating these data into current biodiversity datasets in light of the Kunming-Montreal Global Biodiversity Framework.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales
2.
Ecology ; 104(10): e4151, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37535019

RESUMEN

Alternative migratory strategies can coexist within animal populations and species. Anthropogenic impacts can shift the fitness balance between these strategies leading to changes in migratory behaviors. Yet some of the mechanisms that drive such changes remain poorly understood. Here we investigate the phenotypic differences, and the energetic, behavioral, and fitness trade-offs associated with four different movement strategies (long-distance and short-distance migration, and regional and local residency) in a population of white storks (Ciconia ciconia) that has shifted its migratory behavior over the last decades, from fully long-distance migration toward year-round residency. To do this, we tracked 75 adult storks fitted with GPS/GSM loggers with tri-axial acceleration sensors over 5 years, and estimated individual displacement, behavior, and overall dynamic body acceleration, a proxy for activity-related energy expenditure. Additionally, we monitored nesting colonies to assess individual survival and breeding success. We found that long-distance migrants traveled thousands of kilometers more throughout the year, spent more energy, and >10% less time resting compared with short-distance migrants and residents. Long-distance migrants also spent on average more energy per unit of time while foraging, and less energy per unit of time while soaring. Migratory individuals also occupied their nests later than resident ones, later occupation led to later laying dates and a lower number of fledglings. However, we did not find significant differences in survival probability. Finally, we found phenotypic differences in the migratory probability, as smaller sized individuals were more likely to migrate, and they might be incurring higher energetic and fitness costs than larger ones. Our results shed light on the shifting migratory strategies in a partially migratory population and highlight the nuances of anthropogenic impacts on species behavior, fitness, and evolutionary dynamics.


Asunto(s)
Migración Animal , Aves , Humanos , Animales , Estaciones del Año , Cruzamiento , Metabolismo Energético
3.
Proc Natl Acad Sci U S A ; 120(12): e2212035120, 2023 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-36913571

RESUMEN

Recent studies have suggested that protected areas often fail to conserve target species. However, the efficacy of terrestrial protected areas is difficult to measure, especially for highly vagile species like migratory birds that may move between protected and unprotected areas throughout their lives. Here, we use a 30-y dataset of detailed demographic data from a migratory waterbird, the Whooper swan (Cygnus cygnus), to assess the value of nature reserves (NRs). We assess how demographic rates vary at sites with varying levels of protection and how they are influenced by movements between sites. Swans had a lower breeding probability when wintering inside NRs than outside but better survival for all age classes, generating a 30-fold higher annual growth rate within NRs. There was also a net movement of individuals from NRs to non-NRs. By combining these demographic rates and estimates of movement (into and out of NRs) into population projection models, we show that the NRs should help to double the population of swans wintering in the United Kingdom by 2030. These results highlight the major effect that spatial management can have on species conservation, even when the areas protected are relatively small and only used during short periods of the life cycle.


Asunto(s)
Migración Animal , Anseriformes , Humanos , Animales , Aves , Patos , Estaciones del Año , Demografía
4.
Mov Ecol ; 10(1): 28, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35725653

RESUMEN

BACKGROUND: Migration phenology is shifting for many long-distance migrants due to global climate change, however the timing and duration of migration may influence the environmental conditions individuals encounter, with potential fitness consequences. Species with asynchronous migrations, i.e., with variability in migration timing, provide an excellent opportunity to investigate how of the conditions individuals experience during migration can vary and affect the migratory performance, route, and destination of migrants. METHODS: Here, we use GPS tracking and accelerometer data to examine if timing of autumn migration influences the migratory performance (duration, distance, route straightness, energy expenditure) and migration destinations of a long-distance, asynchronous, migrant, the white stork (Ciconia ciconia). We also compare the weather conditions (wind speed, wind direction, and boundary layer height) encountered on migration and examine the influence of wind direction on storks' flight directions. RESULTS: From 2016 to 2020, we tracked 172 white storks and obtained 75 complete migrations from the breeding grounds in Europe to the sub-Saharan wintering areas. Autumn migration season spanned over a 3-month period (July-October) and arrival destinations covered a broad area of the Sahel, 2450 km apart, from Senegal to Niger. We found that timing of migration influenced both the performance and conditions individuals experienced: later storks spent fewer days on migration, adopted shorter and more direct routes in the Sahara Desert and consumed more energy when flying, as they were exposed to less supportive weather conditions. In the Desert, storks' flight directions were significantly influenced by wind direction, with later individuals facing stronger easterly winds (i.e., winds blowing to the west), hence being more likely to end their migration in western areas of the Sahel region. Contrastingly, early storks encountered more supportive weather conditions, spent less energy on migration and were exposed to westerly winds, thus being more likely to end migration in eastern Sahel. CONCLUSIONS: Our results show that the timing of migration influences the environmental conditions individuals face, the energetic costs of migration, and the wintering destinations, where birds may be exposed to different environmental conditions and distinct threats. These findings highlight that on-going changes in migration phenology, due to environmental change, may have critical fitness consequences for long-distance soaring migrants.

5.
Trends Ecol Evol ; 37(5): 411-419, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35181167

RESUMEN

The ongoing global biodiversity crisis not only involves biological extinctions, but also the loss of experience and the gradual fading of cultural knowledge and collective memory of species. We refer to this phenomenon as 'societal extinction of species' and apply it to both extinct and extant taxa. We describe the underlying concepts as well as the mechanisms and factors that affect this process, discuss its main implications, and identify mitigation measures. Societal extinction is cognitively intractable, but it is tied to biological extinction and thus has important consequences for conservation policy and management. It affects societal perceptions of the severity of anthropogenic impacts and of true extinction rates, erodes societal support for conservation efforts, and causes the loss of cultural heritage.


Asunto(s)
Conservación de los Recursos Naturales , Extinción Biológica , Efectos Antropogénicos , Biodiversidad , Políticas
6.
Sci Rep ; 11(1): 20018, 2021 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-34625581

RESUMEN

Behavioural thermoregulation could buffer the impacts of climate warming on vertebrates. Specifically, the wetting of body surfaces and the resulting evaporation of body fluids serves as a cooling mechanism in a number of vertebrates coping with heat. Storks (Ciconiidae) frequently excrete onto their legs to prevent overheating, a phenomenon known as urohidrosis. Despite the increasingly recognised role of bare and highly vascularised body parts in heat exchange, the ecological and evolutionary determinants of urohidrosis have been largely ignored. We combine urohidrosis data from a scientifically curated media repository with microclimate and ecological data to investigate the determinants of urohidrosis in all extant stork species. Our phylogenetic generalised linear mixed models show that high temperature, humidity and solar radiation, and low wind speed, promote the use of urohidrosis across species. Moreover, species that typically forage in open landscapes exhibit a more pronounced use of urohidrosis than those mainly foraging in waterbodies. Substantial interspecific variation in temperature thresholds for urohidrosis prevalence points to different species vulnerabilities to high temperatures. This integrated approach that uses online data sources and methods to model microclimates should provide insight into animal thermoregulation and improve our capacity to make accurate predictions of climate change's impact on biodiversity.


Asunto(s)
Aves/fisiología , Regulación de la Temperatura Corporal/fisiología , Animales , Conducta Animal/fisiología , Biodiversidad , Cambio Climático , Microclima , Filogenia
7.
J Environ Manage ; 294: 113149, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34218073

RESUMEN

Anthropogenic structures are increasingly encroaching wildlife habitats, creating conflicts between humans and animals. Scaling up renewable energy requires new infrastructures such as power lines, that cause high mortality among birds since they act as obstacles to flight and are used for perching and nesting, which can result in collisions or electrocutions. These interactions often endanger wildlife populations and may also result in high financial costs for companies. Flight behaviour plays a crucial role in collision risk, and the study of flight altitudes enables us to understand what drives birds to fly at collision risk altitudes. This allows the identification of high-risk areas, conditions and bird behaviours, and the implementation of mitigation measures by power line companies. In this study, we use boosted random tree modelling to identify drivers of white stork (Ciconia ciconia) flight altitudes and to investigate the factors that lead them to fly at collision risk altitudes. We found that the main drivers of flight altitude for this soaring bird species were time of day, distance to the nearest landfill site and cloud cover density. Bird age, habitat type and season were comparatively less important. Collision risk increases during crepuscular hours near landfill sites, also in days with high cloud cover density and during the breeding season. In recent years, hundreds to thousands of storks congregate daily at landfill sites to take advantage of the predictability and superabundance of anthropogenic food waste. Some of these sites have high density of power lines, becoming collision risk hotspots for storks and other landfill users. Despite being susceptible to collision, our results suggest that white storks can avoid power lines to a certain extent, by changing their flight altitude at ca. 80 m from these structures. This study shows that the implementation of mitigation measures for existing power lines should be prioritized in areas in the vicinity of landfill sites within white stork distribution ranges, and the projection of new lines should avoid those areas. These measures would benefit species vulnerable to mortality due to power line collision, and it would also reduce associated power outages and economic costs.


Asunto(s)
Altitud , Eliminación de Residuos , Animales , Aves , Vuelo Animal , Alimentos , Humanos , Fitomejoramiento , Instalaciones de Eliminación de Residuos
8.
Conserv Biol ; 35(2): 398-411, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33749027

RESUMEN

Ongoing loss of biological diversity is primarily the result of unsustainable human behavior. Thus, the long-term success of biodiversity conservation depends on a thorough understanding of human-nature interactions. Such interactions are ubiquitous but vary greatly in time and space and are difficult to monitor efficiently at large spatial scales. However, the Information Age also provides new opportunities to better understand human-nature interactions because many aspects of daily life are recorded in a variety of digital formats. The emerging field of conservation culturomics aims to take advantage of digital data sources and methods to study human-nature interactions and thus to provide new tools for studying conservation at relevant temporal and spatial scales. Nevertheless, technical challenges associated with the identification, access, and analysis of relevant data hamper the wider adoption of culturomics methods. To help overcome these barriers, we propose a conservation culturomics research framework that addresses data acquisition, analysis, and inherent biases. The main sources of culturomic data include web pages, social media, and other digital platforms from which metrics of content and engagement can be obtained. Obtaining raw data from these platforms is usually desirable but requires careful consideration of how to access, store, and prepare the data for analysis. Methods for data analysis include network approaches to explore connections between topics, time-series analysis for temporal data, and spatial modeling to highlight spatial patterns. Outstanding challenges associated with culturomics research include issues of interdisciplinarity, ethics, data biases, and validation. The practical guidance we offer will help conservation researchers and practitioners identify and obtain the necessary data and carry out appropriate analyses for their specific questions, thus facilitating the wider adoption of culturomics approaches for conservation applications.


Fuentes de Información Digital y Métodos para la Culturomia de la Conservación Resumen La continua pérdida de biodiversidad es el resultado principal del comportamiento humano insostenible. Por esto, el éxito a largo plazo de la conservación de la biodiversidad depende de una comprensión exhaustiva de las interacciones humano-naturaleza. Dichas interacciones son ubicuas pero varían enormemente en el tiempo y el espacio, lo que dificulta su monitoreo eficiente a escalas espaciales amplias. Sin embargo, la Era de la Información también nos proporciona nuevas oportunidades para comprender de mejor manera las interacciones humano-naturaleza pues muchos aspectos de la vida diaria quedan registrados en una variedad de formatos digitales. El campo emergente de la culturomia de la conservación busca aprovechar los recursos y los métodos digitales para estudiar las interacciones humano-naturaleza y así proporcionar nuevas herramientas para el estudio de la conservación a escalas temporales y espaciales relevantes. No obstante, las dificultades técnicas asociadas con la identificación, acceso y análisis de la información relevante obstaculizan la adopción más amplia de los métodos de la culturomia. Para ayudar a superar estas barreras proponemos un marco de trabajo de investigación de culturomia de la conservación que aborde la obtención de datos, el análisis y los sesgos inherentes. Entre las principales fuentes de datos sobre culturomia se incluyen las páginas web, las redes sociales y otras plataformas digitales a partir de las cuales se pueden obtener medidas del contenido y la participación. Normalmente se busca obtener datos crudos a partir de este tipo de plataformas, pero esto requiere que se tengan en consideración las vías de acceso, el almacenaje y la preparación de la información para su posterior análisis. Los métodos para el análisis de datos incluyen analísis de redes para explorar las conexiones entre los temas, el análisis de series de tiempo para los datos temporales y el modelado espacial para resaltar los patrones espaciales. Los desafíos sobresalientes asociados a la investigación en culturomia incluyen temas de interdisciplinariedad, ética, sesgos de datos y validación. La orientación práctica que ofrecemos ayudará a los investigadores y practicantes de la conservación a identificar y obtener los datos necesarios. También les ayudará a realizar análisis apropiados para responder a sus preguntas específicas, facilitando así la adopción más amplia de las estrategias de culturomia para su aplicación en la conservación.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Humanos , Almacenamiento y Recuperación de la Información
10.
J Anim Ecol ; 90(5): 1109-1121, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33550590

RESUMEN

Sexual segregation in foraging strategies has been little studied in marine species with slight sexual size dimorphism (SSD), particularly regarding the role of environmental conditions and fishery activities. Sexual differences in fishery attendance are of particular concern because uneven mortality associated with bycatch may exacerbate impacts in wildlife populations. Using a seabird species with slight SSD, the Scopoli's shearwater Calonectris diomedea, we assessed sexual differences in foraging strategies and evaluated whether annual environmental conditions and fishery activity shaped such differences. We used a 4-year dataset combining bird GPS tracking, stable isotope analysis, the North Atlantic Oscillation index (NAO, as main proxy of the annual environmental conditions), and fishing vessel positioning data (Vessel Monitoring System, VMS) from the North Western Mediterranean, a region under intense fishery pressure. From 2012 to 2015, we tracked 635 foraging trips from 78 individuals. Females showed a greater foraging effort, a lower fishery attendance, a lower trophic level, and a narrower isotopic niche width than males. Moreover, in years with unfavourable environmental conditions, both sexes showed a lower fishery attendance and increased foraging effort compared to the year with most favourable conditions. Our results revealed that environmental conditions influence space use, feeding resources and fishery attendance differently in males and females, overall suggesting competitive exclusion of females by males from main foraging areas and feeding resources, particularly in unfavourable environmental conditions. We highlight the importance of evaluating sexual segregation under disparate environmental conditions, particularly in species with slight SSD, since segregation may pass otherwise unnoticed if only years with similar environmental conditions are considered. The higher fishery attendance of males likely explains the male-biased bycatch ratio for this species. Thus, inter-sexual differences in foraging strategies can lead to an unbalanced exposure to relevant threats and have implications for the conservation of long-lived species.


La segregación sexual en especies con dimorfismo sexual poco acusado ha sido escasamente estudiada, particularmente en relación al papel de las condiciones ambientales y las pesquerías en las estrategias de búsqueda de alimento. Diferencias entre sexos en la asociación con pesquerías son de especial interés, ya que el impacto de las capturas accidentales sobre la dinámica poblacional podría magnificarse. En este trabajo exploramos las diferencias entre sexos en las estrategias de búsqueda de alimento en la pardela cenicienta (Calonectris diomedea) en el noroeste del Mediterráneo, y evaluamos si cambios anuales en las condiciones ambientales y las pesquerías modulan dichas diferencias. Utilizamos cuatro años de datos, integrando el seguimiento GPS de las aves, el análisis de isótopos estables, el índice NAO, y el seguimiento remoto de barcos pesqueros que operan en la zona (datos VMS). Entre 2012 y 2015 obtuvimos 635 viajes de alimentación de 78 individuos. Encontramos diferencias en las estrategias de búsqueda de alimento entre sexos a pesar del dimorfismo sexual poco acusado de esta especie. En comparación con los machos, las hembras mostraron mayor esfuerzo (viajes más largos en tiempo y distancia), menor asociación con barcos de pesca, menor nivel trófico (es decir, valores de δ15 N en plasma que apuntan a un menor consumo de descartes) y un nicho isotópico más estrecho. Nuestros resultados revelaron que las condiciones ambientales influyen en las diferencias sexuales en las estrategias de búsqueda y uso de recursos de alimentación, así como en la interacción con pesquerías. En general, esto sugiere cierta exclusión competitiva de machos hacia hembras, particularmente en años desfavorables. Incluir años con condiciones ambientales dispares en el análisis puede ayudar a determinar la segregación sexual en especies con dimorfismo sexual poco acusado. Además, en especies longevas, las diferencias sexuales en las estrategias de búsqueda de alimento pueden conllevar diferente exposición a ciertas amenazas como las capturas accidentales en artes de pesca, lo que debe considerarse en el diseño de estrategias de conservación.


Asunto(s)
Conducta Alimentaria , Explotaciones Pesqueras , Animales , Aves , Femenino , Masculino , Caracteres Sexuales
11.
Nat Commun ; 11(1): 5719, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33203869

RESUMEN

Billions of vertebrates migrate to and from their breeding grounds annually, exhibiting astonishing feats of endurance. Many such movements are energetically costly yet there is little consensus on whether or how such costs might influence schedules of survival and reproduction in migratory animals. Here we provide a global analysis of associations between migratory behaviour and vertebrate life histories. After controlling for latitudinal and evolutionary patterns, we find that migratory birds and mammals have faster paces of life than their non-migratory relatives. Among swimming and walking species, migrants tend to have larger body size, while among flying species, migrants are smaller. We discuss whether pace of life is a determinant, consequence, or adaptive outcome, of migration. Our findings have important implications for the understanding of the migratory phenomenon and will help predict the responses of bird and mammal species to environmental change.


Asunto(s)
Migración Animal , Aves/fisiología , Mamíferos/fisiología , Animales , Tamaño Corporal , Rasgos de la Historia de Vida , Longevidad , Filogenia
12.
PLoS Biol ; 18(10): e3000935, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33119582

RESUMEN

The ongoing digital revolution in the age of big data is opening new research opportunities. Culturomics and iEcology, two emerging research areas based on the analysis of online data resources, can provide novel scientific insights and inform conservation and management efforts. To date, culturomics and iEcology have been applied primarily in the terrestrial realm. Here, we advocate for expanding such applications to the aquatic realm by providing a brief overview of these new approaches and outlining key areas in which culturomics and iEcology are likely to have the highest impact, including the management of protected areas; fisheries; flagship species identification; detection and distribution of threatened, rare, and alien species; assessment of ecosystem status and anthropogenic impacts; and social impact assessment. When deployed in the right context with awareness of potential biases, culturomics and iEcology are ripe for rapid development as low-cost research approaches based on data available from digital sources, with increasingly diverse applications for aquatic ecosystems.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Animales Salvajes/fisiología , Sesgo , Especies en Peligro de Extinción , Explotaciones Pesqueras
13.
Trends Ecol Evol ; 35(7): 630-639, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32521246

RESUMEN

Digital data are accumulating at unprecedented rates. These contain a lot of information about the natural world, some of which can be used to answer key ecological questions. Here, we introduce iEcology (i.e., internet ecology), an emerging research approach that uses diverse online data sources and methods to generate insights about species distribution over space and time, interactions and dynamics of organisms and their environment, and anthropogenic impacts. We review iEcology data sources and methods, and provide examples of potential research applications. We also outline approaches to reduce potential biases and improve reliability and applicability. As technologies and expertise improve, and costs diminish, iEcology will become an increasingly important means to gain novel insights into the natural world.


Asunto(s)
Biodiversidad , Ecología , Reproducibilidad de los Resultados
14.
Proc Biol Sci ; 286(1914): 20192227, 2019 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-31662087

RESUMEN

Species interactions are central in predicting the impairment of biodiversity with climate change. Trophic interactions may be altered through climate-dependent changes in either predator food preferences or prey communities. Yet, climate change impacts on predator diet remain surprisingly poorly understood. We experimentally studied the consequences of 2°C warmer climatic conditions on the trophic niche of a generalist lizard predator. We used a system of semi-natural mesocosms housing a variety of invertebrate species and in which climatic conditions were manipulated. Lizards in warmer climatic conditions ate at a greater predatory to phytophagous invertebrate ratio and had smaller individual dietary breadths. These shifts mainly arose from direct impacts of climate on lizard diets rather than from changes in prey communities. Dietary changes were associated with negative changes in fitness-related traits (body condition, gut microbiota) and survival. We demonstrate that climate change alters trophic interactions through top-predator dietary shifts, which might disrupt eco-evolutionary dynamics.


Asunto(s)
Cambio Climático , Dieta , Cadena Alimentaria , Animales , Biodiversidad , Evolución Biológica , Conducta Predatoria
15.
PLoS One ; 14(7): e0220400, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31344107

RESUMEN

Loss of natural wetlands is a global phenomenon that has severe consequences for waterbird populations and their associated ecosystem services. Although agroecosystems can reduce the impact of natural habitat loss, drivers of use of such artificial habitats by waterbirds remain poorly understood. Using the cosmopolitan northern pintail Anas acuta as a model species, we monitored home-range and fine-scale resource selection across the agricultural landscape. Individuals were tracked using GPS-GSM transmitters, and a suite of environmental and landscape features were measured throughout the winter seasons. Spatial patterns of habitat use were analysed using generalized linear mixed effect models by integrating field-observations with GPS telemetry. All birds used rice fields as foraging grounds at night and commuted to an adjacent reservoir to roost during daylight. Home-ranges and maximum foraging distances of nocturnally foraging birds increased with decreasing availability of flooded fields, and were positively correlated with moonlight levels. Birds selected flooded rice paddies (water depth range: 9-21 cm) with standing stubble and substrate with pebbles smaller than 0.5 cm in diameter. Density of rice seeds, rice paddy size, and other environmental and landscape features did not emerge as significant predictors. Our findings indicate that nocturnal foraging of northern pintails within rice fields is driven primarily by straw manipulation, water level and substrate pebble size. Thus, the presence of standing stubble in flooded paddies with soft bottoms should be prioritized to improve foraging areas for dabbling ducks. These management procedures in themselves would not increase economic costs or affect rice production and could be applied for dabbling-duck conservation throughout the world.


Asunto(s)
Agricultura , Anseriformes/fisiología , Ritmo Circadiano/fisiología , Ecosistema , Humedales , Agricultura/métodos , Migración Animal/fisiología , Animales , Conducta Animal , Inundaciones , Oryza/crecimiento & desarrollo , Ríos , Estaciones del Año , España
17.
Sci Rep ; 6: 37373, 2016 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-27876852

RESUMEN

Fisheries provide an abundant and predictable food source for many pelagic seabirds through discards, but also pose a major threat to them through bycatch, threatening their populations worldwide. The reform of the European Common Fisheries Policy (CFP), which intends to ban discards through the landing obligation of all catches, may force seabirds to seek alternative food sources, such as baited hooks from longlines, increasing bycatch rates. To test this hypothesis we performed a combined analysis of seabird-fishery interactions using as a model Scopoli's shearwaters Calonectris diomedea in the Mediterranean. Tracking data showed that the probability of shearwaters attending longliners increased exponentially with a decreasing density of trawlers. On-board observations and mortality events corroborated this result: the probability of birds attending longliners increased 4% per each trawler leaving the longliner proximity and bird mortality increased tenfold when trawlers were not operating. Therefore, the implementation of the landing obligation in EU waters will likely cause a substantial increase in bycatch rates in longliners, at least in the short-term, due to birds switching from trawlers to longliners. Thus the implementation of the landing obligation must be carefully monitored and counterbalanced with an urgent implementation of bycatch mitigation measures in the longline fleet.


Asunto(s)
Aves/fisiología , Ecosistema , Conducta Alimentaria/fisiología , Explotaciones Pesqueras , Animales , Conservación de los Recursos Naturales , Geografía , Islas , Mar Mediterráneo , Dinámica Poblacional , Factores de Riesgo , España
18.
Sci Rep ; 6: 28595, 2016 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-27345214

RESUMEN

In recent years numerous studies have documented the effects of a changing climate on the world's biodiversity. Although extreme weather events are predicted to increase in frequency and intensity and are challenging to organisms, there are few quantitative observations on the survival, behaviour and energy expenditure of animals during such events. We provide the first data on activity and energy expenditure of birds, Eurasian cranes Grus grus, during the winter of 2013-14, which saw the most severe floods in SW England in over 200 years. We fitted 23 cranes with telemetry devices and used remote sensing data to model flood dynamics during three consecutive winters (2012-2015). Our results show that during the acute phase of the 2013-14 floods, potential feeding areas decreased dramatically and cranes restricted their activity to a small partially unflooded area. They also increased energy expenditure (+15%) as they increased their foraging activity and reduced resting time. Survival did not decline in 2013-14, indicating that even though extreme climatic events strongly affected time-energy budgets, behavioural plasticity alleviated any potential impact on fitness. However under climate change scenarios such challenges may not be sustainable over longer periods and potentially could increase species vulnerability.


Asunto(s)
Aves/fisiología , Animales , Biodiversidad , Cambio Climático , Ecología , Metabolismo Energético/fisiología , Inglaterra , Inundaciones , Estaciones del Año , Tiempo (Meteorología)
19.
Oecologia ; 178(4): 1077-91, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25851406

RESUMEN

Migratory shorebirds inhabit environments that may yield contrasting salinity-temperature regimes-with widely varying osmoregulatory demands, even within a given species-and the question is: by which physiological means and at which organisational level do they show adjustments with respect to these demands? Red knots Calidris canutus winter in coastal areas over a range of latitudes. The nominal subspecies winters in salty areas in the tropics, whereas the subspecies Calidris canutus islandica winters in north-temperate regions of comparatively lower salinities and temperatures. In this study, both subspecies of red knot were acclimated to different salinity (28/40‰)-temperature (5/35 °C) combinations for 2-week periods. We then measured food/salt intakes, basal metabolic rate (BMR), body mass and temperature, fat and salt gland scores, gizzard mass, heat-shock proteins, heterophils/lymphocytes (H/L) ratio and plasma Na(+) to assess the responses of each taxon to osmoregulatory challenges. High salinity (HS)-warm-acclimated birds reduced food/salt intake, BMR, body mass, fat score and gizzard mass, showing that salt/heat loads constrained energy acquisition rates. Higher salt gland scores in saltier treatments indicated that its size was adjusted to higher osmoregulatory demands. Elevated plasma Na(+) and H/L ratio in high-salinity-warm-acclimated birds indicated that salt/heat loads might have a direct effect on the water-salt balance and stress responses of red knots. Subspecies had little or no effect on most measured parameters, suggesting that most adjustments reflect phenotypic flexibility rather than subspecific adaptations. Our results demonstrate how salinity and temperature affect various phenotypic traits in a migrant shorebird, highlighting the importance of considering these factors jointly when evaluating the environmental tolerances of air-breathing marine taxa.


Asunto(s)
Aclimatación , Charadriiformes/fisiología , Salinidad , Cloruro de Sodio/metabolismo , Estrés Fisiológico , Temperatura , Animales , Metabolismo Basal , Cruzamiento , Fenotipo , Estaciones del Año , Equilibrio Hidroelectrolítico
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