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Contemporary conservation science requires mediating conflicts among nonhuman species, but the grounds for favoring one species over another can be unclear. We examined the premises through which wildlife managers picked sides in an interspecies conflict: seabird conservation in the Gulf of Maine (GOM). Managers in the GOM follow a simple narrative dubbed the gull problem. This narrative assumes Larus gulls are overpopulated and unnatural in the region. In turn, these assumptions make gulls an easy target for culling and lethal control when the birds come into conflict with other seabirds, particularly Sterna terns. Surveying historical, natural historical, and ecological evidence, we found no scientific support for the claim that Larus gulls are overpopulated in the GOM. Claims of overpopulation originated from a historical context in which rising gull populations became a nuisance to humans. Further, we found only limited evidence that anthropogenic subsidies make gulls unnatural in the region, especially when compared with anthropogenic subsidies provided for other seabirds. The risks and consequences of leveraging precarious assumptions include cascading plans to cull additional gull populations, obfuscation of more fundamental environmental threats to seabirds, and the looming paradox of gull conservation—even if one is still inclined to protect terns in the GOM. Our close look at the regional history of a conservation practice thus revealed the importance of not only conservation decisions, but also conservation decision‐making. [ABSTRACT FROM AUTHOR]

El palangre de superficie es un arte pesca dirigido a la captura de peces pelágicos, el cual puede enganchar especies vulnerables como tiburones, tortugas, aves y mamíferos marinos. El objetivo del presente trabajo fue analizar la incidencia de estos grupos en la pesca de barcos nodrizas ecuatorianos. La base de datos fue proporcionada por el Instituto Público de Investigación de Acuicultura y Pesca, correspondiendo a registros de observadores a bordo, para el período 2019-2023. La principal carnada utilizada fue Dosidicus gigas. Se encontró el uso de anzuelos tipo “C” y “J”, siendo el segundo el más utilizado. Un total de 14 especies de tiburones, una de raya (Pteroplatytrygon violacea) y una de mantarraya (Mobula birostris) incidieron en la pesca con palangre. Prionace glauca, Alopias pelagicus, Carcharhinus falciformis, A. superciliosus e Isurus oxyrinchus tuvieron la incidencia anual más alta. La incidencia de tiburones mostró una baja relación con la cantidad de lances. Las aves marinas reportadas fueron 25 especies, alimentándose o deambulando. Oceanites gracilis y Procellaria parkinsoni tuvieron la mayor incidencia. Los delfines fueron los mamíferos marinos más representativos, el Género Delphinus fue el más abundante, sin evidencia de mortalidad. Las tortugas Chelonia mydas y Lepidochelys olivacea presentaron registros recurrentes, mientras que Caretta caretta y Dermochelys coriacea fueron esporádicas. Los tiburones fueron el único grupo que presentó mortalidad, mientras que, las tortugas presentaron lesiones corporales sin mortalidad. Bajo este escenario, es necesario desarrollar y aplicar medidas de manejo que promuevan la protección de las especies vulnerables.

Seabirds interact with fishing vessels to consume fishing discards and baits, sometimes resulting in incidental capture (bycatch) and the death of the bird, which has clear conservation implications. To understand seabird–fishery interactions at large spatiotemporal scales, researchers are increasing their use of simultaneous seabird and fishing vessel tracking. However, vessel tracking data can contain gaps due to technical problems, illicit manipulation, or lack of adoption of tracking monitoring systems. These gaps might lead to underestimating the fishing effort and bycatch rates and jeopardize the effectiveness of marine conservation. We deployed bird‐borne radar detector tags capable of recording radar signals from vessels. We placed tags on 88 shearwaters (Calonectris diomedea, Calonectris borealis, and Calonectris edwardsii) that forage in the northwestern Mediterranean Sea and the Canary Current Large Marine Ecosystem. We modeled vessel radar detections registered by the tags in relation to gridded automatic identification system (AIS) vessel tracking data to examine the spatiotemporal dynamics of seabird–vessel interactions and identify unreported fishing activity areas. Our models showed a moderate fit (area under the curve >0.7) to vessel tracking data, indicating a strong association of shearwaters to fishing vessels in major fishing grounds. Although in high‐marine‐traffic regions, radar detections were also driven by nonfishing vessels. The tags registered the presence of potential unregulated and unreported fishing vessels in West African waters, where merchant shipping is unusual but fishing activity is intense. Overall, bird‐borne radar detectors showed areas and periods when the association of seabirds with legal and illegal fishing vessels was high. Bird‐borne radar detectors could improve the focus of conservation efforts. [ABSTRACT FROM AUTHOR]

The "island syndrome" refers to similarity in the biology of island organisms, but its generality is questionable, as the scope of species and traits examined are often limited. Here, I show that birds breeding exclusively on islands (breeding island endemics) evolved smaller clutches, using a dataset of 4,530 bird species. Using an inclusive definition of a breeding island endemic, which also encompasses migratory species and seabirds, I examine the evolution of clutch sizes in island breeding species using phylogenetic generalized linear models. Across disparate phylogenetic hypotheses, and after accounting for biological and geographical co-variables, I show that breeding island endemic landbirds (470 species) evolved smaller clutch sizes than continental breeding species (3,818 species). I show that the evolution of clutch size follows the expectations of the island syndrome, as among breeding island endemic landbirds there is a positive relationship between clutch size and breeding range area. Finally, I reinforce the view that the island syndrome is a general pattern in birds, spanning diverse phylogenetic and ecological groups, by showing that in a seabird-only dataset (242 species), breeding island endemic seabirds show evolution of smaller clutch sizes. In a model of the full dataset of both landbirds and seabirds (4,530 species) there was no evidence of an interaction of being a seabird with breeding island endemicity, showing that seabirds and landbirds respond in the same way. This study, using more than 40% of all bird species, provides the first evidence of a general evolutionary response in a life history trait, clearly showing the island syndrome as a general evolutionary tendency associated with island environments. [ABSTRACT FROM AUTHOR]

The expanding use of wind farms as a source of renewable energy can impact bird populations due to collisions and other factors. Globally, seabirds are one of the avian taxonomic groups most threatened by anthropogenic disturbance; adequately assessing the potential impact of off-shore wind farms (OWFs) is important for developing strategies to avoid or minimize harm to their populations. We estimated avoidance rates of OWFs--the degree to which birds show reduced utilization of OWF areas--by Sandwich Terns (Thalasseus sandvicensis) at 2 breeding colonies in western Europe: Scolt Head (United Kingdom) and De Putten (the Netherlands). The foraging ranges of birds from each colony overlapped with multiple OWFs. We modeled GPS tracking data using integrated step selection functions (iSSFs) to estimate the relative selection of habitats at the scale of time between successive GPS relocations--in our case, 10 min, in which Sandwich Terns traveled ~2 km on average. Besides the effects of OWFs and the direct surroundings of OWFs, iSSFs considered distance from the colony and habitat characteristics (water depth and sediment grain size) as well as movement characteristics. Macro-avoidance rates, where 1 means complete avoidance, were estimated at 0.54 (95% CI: 0.35, 0.7) for birds originating from Scolt Head and 0.41 (95% CI: 0.21, 0.56) for those from De Putten. Estimates for individual OWFs also indicated avoidance but were associated with considerable uncertainty. Our results were inconclusive with regard to the behavioral response to the areas directly surrounding OWFs (within 1.5 km); estimates suggested indifference and avoidance, and were associated with large uncertainty. Avoidance rate of OWFs significantly increased with turbine density, suggesting that OWF design may help to reduce the impact of OWFs on Sandwich Terns. The partial avoidance of OWFs by Sandwich Terns implies that the species will experience risks of collision and habitat loss due to OWFs constructed within their foraging ranges. [ABSTRACT FROM AUTHOR]

Seabirds spend most of the year offshore, out of human sight, covering great distances while migrating and foraging for food often in remote areas of the high seas. Several small seabirds that anthropogenic activities might threaten have hitherto remained untracked. One such species is the anti-tropical White-faced Storm-petrel Pelagodroma marina. Indeed, its movements and activity patterns are largely unknown, although often regarded as dispersive. In this study, we aimed to identify the post-breeding movements and the daily activity patterns of White-faced Storm-petrels breeding in Cabo Verde (P. m. eadesorum). We tracked five adults with geolocators (GLS) between 2019 and 2022 and modelled their routes using Satellite Geolocation for Animal Tracking (SGAT). We programmed geolocators to record when the bird was dry or on the water to understand their daily activity patterns during the non-breeding period. Results showed that the White-faced Storm-petrels breeding in Cabo Verde are truly migratory, heading towards the northwest Atlantic in May-June and returning in October-November through the northeast towards Cabo Verde, following a clockwise movement. Birds spent the non-breeding period in areas associated with seamounts along the mid-Atlantic Ridge and south of the Azores. In addition, we found that the species is mainly active at night during the non-breeding season, suggesting that it takes advantage of the diel vertical migration of zooplankton and nekton associated with seamounts. The time spent on the water increased before returning to the colony, probably due to reduced flying ability during the moulting period. Our data add to the growing evidence that the North-central Atlantic is a crucial location for the conservation of pelagic seabirds and highlights the need to protect these remote areas from the increasing human impact on the high seas.—Medrano, F., Repullés, K., Militão, T., Leal, A. & González-Solís, J. (2024). Migratory movements and activity patterns of White-faced Storm-petrels Pelagodroma marina breeding in Cabo Verde. Ardeola, 71: 101-118. Las aves marinas pelágicas pasan la mayor parte del año en alta mar, recorriendo grandes distancias y a menudo en áreas remotas poco protegidas de alta mar. Considerando que varias especies de aves marinas pueden estar siendo afectadas por actividades antrópicas durante su migración, es relevante conocer las zonas visitadas durante esta etapa. Una especie cuya migración es poco conocida es el paíño pechialbo Pelagodroma marina. Hasta ahora, no se había investigado si realizan una migración o solo existe dispersión. Además, la especie es nocturna durante la incubación y diurna/nocturna durante la cría del pollo, pero no se conocen sus patrones de actividad durante la migración. En este estudio, caracterizamos los movimientos migratorios del paíño pechialbo en Cabo Verde (P. m. eadesorum), rastreando seis adultos con geolocalizadores (GLS) entre 2019 y 2022, y modelamos sus rutas migratorias. Para comprender su actividad diaria fuera, registramos el tiempo que pasan en el agua mediante geolocalizadores. Los resultados mostraron que la especie migra en mayo-junio dirigiéndose hacia el noroeste del Atlántico, y regresan en octubre-noviembre por el noreste hacia Cabo Verde, en el sentido de las agujas del reloj. Las principales áreas no reproductivas están ubicadas a lo largo de la Dorsal Atlántica y al sur de Azores, un área con numerosos montes submarinos. Los datos de actividad mostraron que la especie es principalmente nocturna y que el tiempo que pasan en el agua tiende a aumentar antes de regresar a la colonia, probablemente debido a una capacidad de vuelo disminuida durante el proceso de muda. Nuestros datos se suman a la evidencia que muestra que el Atlántico norte central es un sitio clave para la conservación de las aves marinas pelágicas y resalta la necesidad de proteger estas áreas remotas para mitigar los crecientes impactos de las actividades humanas en alta mar.—Medrano, F., Repullés, K., Militão, T., Leal, A. y González-Solís, J. (2024). Movimientos migratorios y patrones de actividad de los paíños pechialbos Pelagodroma marina que anidan en Cabo Verde. Ardeola, 71: 101-118. [ABSTRACT FROM AUTHOR]

The Mediterranean Shag Gulosus aristotelis desmarestii is a conservation priority seabird endemic to the Mediterranean and Black Seas that is considered a valuable sentinel of marine ecosystem health. However, knowledge of its population size and dynamics in the Adriatic Sea is limited. Here, the majority of the population breeds in Croatia, with a high proportion of birds migrating northwards to the Gulf of Trieste and Venice Lagoon during the non-breeding period. To bridge this knowledge gap, a first coordinated census was undertaken in 2020 and 2021 in the Adriatic region (Italy, Slovenia and Croatia), which supports 20-33% of the total non-breeding Mediterranean subspecies population. In 2020 a total of 4,993 birds were counted while in 2021 the count was 4,871. Italy hosted the largest number of birds (x̄ = 3,040), followed by Croatia (x̄ = 951) and Slovenia (x̄ = 941), with most of the birds (c. 69%) roosting on mussel farms. To fully comprehend the non-breeding population dynamics, we conducted an estimation of the 13-year (2010-2022) population trend in the Gulf of Trieste. During this period, the population strongly declined (–44.7%) for reasons yet to be identified. In 2012-2014, a population fluctuation coincided with an exceptionally wet winter and spring at the Croatian breeding colonies. It is possible that changes in migration strategy, such as new migratory routes, by this partial migrant may have partially offset the decline of birds in the Gulf of Trieste, as the Venice Lagoon population increased during the same period. Overall, the Adriatic population appears to be declining and yet subject to dynamic changes in its non-breeding distribution. To fully comprehend the reasons behind this trend, further research of both breeding and non-breeding populations is necessary. —Scridel, D., Utmar, P., Koce, U., Kralj, J., Baccetti, N., Candotto, S., Ciriaco, S., De Luca, M., Pascucci, M., Sartori, A., Tinarelli, R., Sava, S., Vicario, G. & Spoto, M. (2024). Conservation status of the Mediterranean Shag Gulosus aristotelis desmarestii in the Adriatic Sea during the non-breeding period: baseline population, trends, threats and knowledge gaps. Ardeola, 71: 19-42. El cormorán moñudo mediterráneo Gulosus aristotelis desmarestii es una especie prioritaria de conservación, endémica del mar Mediterráneo y el Mar Negro, y se considera un valioso centinela de la salud del ecosistema marino. Sin embargo, el conocimiento sobre el tamaño y la dinámica de la población de G. a. desmarestii en el Mar Adriático es limitado. Aquí, la mayoría de la población se reproduce en Croacia, con una alta proporción de aves que migran hacia el norte hasta el golfo de Trieste y la laguna de Venecia durante el período no reproductivo. Para cerrar esta brecha de conocimiento, se realizó un primer censo coordinado en 2020 y 2021 en la región del Adriático (Italia, Eslovenia y Croacia), que alberga del 20% al 33% de la población total de la subespecie mediterránea en el período no reproductivo. En 2020 se contabilizaron un total de 4.993 aves, mientras que en 2021 la cifra fue de 4.871. Italia albergó el mayor número de aves (x̄ = 3,040), seguida de Croacia (x̄ = 951) y Eslovenia (x̄ = 941), y la mayoría de las aves (aproximadamente el 69%) se posaron en granjas de mejillones. Para comprender completamente la dinámica de la población en el período no reproductivo, se realizó una estimación de la tendencia de la población en el golfo de Trieste durante 13 años (2010-2022). Durante este período, la población ha experimentado un fuerte declive (–44.7%) por razones aún por identificar. En 2012-2014, se observó una fluctuación temporal de la población coincidiendo con un invierno y primavera excepcionalmente húmedos en las colonias de reproducción croatas. Además, es posible que los cambios en la estrategia de migración (es decir, nuevas rutas migratorias) de esta especie parcialmente migratoria hayan contrarrestado la disminución de las aves en el golfo de Trieste, ya que hubo un aumento de la población en la laguna de Venecia durante el mismo período. En general, la población del Adriático parece estar disminuyendo y su distribución en el período no reproductivo está sujeta a cambios dinámicos. Para comprender completamente las razones detrás de esta tendencia, se necesitan investigaciones adicionales sobre la población en período reproductivo y no reproductivo.—Scridel, D., Utmar, P., Koce, U., Kralj, J., Baccetti, N., Candotto, S., Ciriaco, S., De Luca, M., Pascucci, M., Sartori, A., Tinarelli, R., Sava, S., Vicario, G. y Spoto, M. (2024). Estado de conservación del cormorán moñudo mediterráneo Gulosus aristotelis desmarestii en el mar Adriático durante el período no reproductivo: población de referencia, tendencias, amenazas y lagunas de conocimiento. Ardeola, 71: 19-42. [ABSTRACT FROM AUTHOR]

In the midst of the sixth mass extinction, limited resources are forcing conservationists to prioritize which species and places will receive conservation action. Evolutionary distinctiveness measures the isolation of a species on its phylogenetic tree. Combining a species' evolutionary distinctiveness with its globally endangered status creates an EDGE score. We use EDGE scores to prioritize the places and species that should be managed to conserve bird evolutionary history. We analyzed all birds in all countries and important bird areas. We examined parrots, raptors, and seabirds in depth because these groups are especially threatened and relatively speciose. The three focal groups had greater median threatened evolutionary history than other taxa, making them important for conserving bird evolutionary history. Australia, Brazil, Indonesia, Madagascar, New Zealand, and the Philippines were especially critical countries for bird conservation because they had the most threatened evolutionary history for endemic birds and are important for parrots, raptors, and seabirds. Increased enforcement of international agreements for the conservation of parrots, raptors, and seabirds is needed because these agreements protect hundreds of millions of years of threatened bird evolutionary history. Decisive action is required to conserve the evolutionary history of birds into the Anthropocene. [ABSTRACT FROM AUTHOR]

Climate change has resulted in a marked advancement in the breeding phenology of many bird species. Since the timing of many monitoring programs is based on calendar dates, changes in the timing of birds' breeding seasons may result in a mismatch with the census period. Using data from a long-term population study of Common Murres (Uria aalge; Common Guillemots in Europe) on Skomer Island, Wales, together with simulations, we show that the 2-week advance in the timing of breeding in Common Murres between 1973 and 2020 has serious implications for the timing of census counts. We show that because censuses have traditionally been conducted during the same fixed calendar period each year, the size of the breeding population has been underestimated. We recommend that censuses of breeding seabirds be made relative to the median egg-laying date rather than on specific calendar dates. Since climate change has resulted in a widespread advance in the timing of birds' breeding seasons in the northern hemisphere, our results may be relevant to Common Murres at other colonies, and to other bird species worldwide. [ABSTRACT FROM AUTHOR]

With the projected increases in shipping activity and hydrocarbon extraction globally, there is an increased risk of negative ecological impacts from oil pollution on the marine environment, including seabirds. Oil Vulnerability Indices (OVIs) are a common approach to assess seabird species vulnerability to oil pollution and to identify where species are most at risk, typically across regional spatial scales and for a relatively limited number of species. This approach generally requires comprehensive data on at-sea distributions and densities; however, for many regions, these data are limited. We present a simplified OVI to assess seabird species vulnerability to oil pollution. To create the spatial component of the OVI, we used a predictive foraging radius approach, using existing colony size and foraging range data, to project at-sea distributions of seabird populations during the breeding season. We demonstrate this approach over a large spatial scale, the eastern North Atlantic, which includes areas where seabird at-sea data are lacking. Our results reveal areas off west Greenland, Iceland, and Norway where seabirds are most vulnerable to oil pollution during the breeding season, largely driven by large colonies of auks (Alcidae). We also identify locations along the coast of mainland Norway, Iceland, and Scotland, where seabirds are particularly at risk to oil pollution associated with major shipping routes. Identifying areas where species are most at risk can help inform where, and which, measures should be put in place to mitigate the impacts of oil pollution, such as protecting and avoiding high risk areas, for example, through adopting dynamic Areas to be Avoided (ATBAs). Our simplified OVI combined with the predictive foraging radius approach can be adapted to other regions globally that lack seabird-at-sea distribution data, to other marine wildlife, and to assess risk from hydrocarbon extraction and other anthropogenic threats, including fishing activities and offshore renewable developments. [ABSTRACT FROM AUTHOR]

Man-made debris is a global problem for seabirds because it is ingested by many species. Markham's Storm Petrel Hydrobates markhami, which breeds in the Atacama Desert and is endemic to the Humboldt Current in the eastern South Pacific, has been poorly studied in this regard. Earlier studies found low levels of man-made debris in the species' diet. We quantified the present-day frequency-occurrence of man-made debris in fledglings and adults of Markham's Storm Petrel in Chile. We found that 16 of 25 fledglings and all adults contained man-made debris in their digestive tract, indicating the prevalence of man-made debris in this species' diet is higher than previously reported. Additional work is needed to assess the importance of this finding to conservation efforts. [ABSTRACT FROM AUTHOR]

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Censos recientes revelan un declive poblacional acusado de la gaviota patiamarilla Larus michahellis en buena parte de su área de distribución. Ya a mediados de la década de 2010 se registró en la costa vasca un declive cercano al 50% respecto al censo de 2007. Tras repetir el censo en 2021, el objetivo de este artículo es (1) actualizar el tamaño poblacional de la especie en la región, (2) calcular su tendencia y (3) evaluar su actual estado de conservación. En términos absolutos la población ha pasado de un promedio de unas 4200 parejas reproductoras durante la década de 2000 a 1861 parejas en 2021 (56% de disminución). Hay pequeñas colonias, especialmente en torno al estuario del río Nervión, para las que no se tienen datos en 2021, por lo que la cifra dada para este año sería ligeramente mayor. Regionalmente, no obstante, se observan diferencias notables. En Gipuzkoa la población ha disminuido un 6%, mientras que en Bizkaia el declive alcanza un 82%. El número de colonias tiende a disminuir ligeramente, pasando de un máximo de 27 colonias en la década de 2000 a 24 en 2021. Además, el número de colonias con más de 100 parejas ha pasado de 10 durante la década de 2000 a 4 en la actualidad. Cabe mencionar: (1) el fuerte descenso o práctica desaparición de las que fueron las colonias más importantes de la costa vasca, situadas en Bizkaia (destacan en este contexto Lekeitio, Izaro y Aketx) y (2) el mantenimiento de las colonias más orientales, situadas en Gipuzkoa, que convierte a Ulia en la colonia más numerosa de la costa vasca en la actualidad. Otro aspecto de interés es la creación de nuevas colonias en el denominado Gran Bilbao, ubicadas a lo largo del estuario del Nervión. De continuar el declive, la especie podría rarificarse como reproductora en varios tramos de costa y pasar a estar casi amenazada. Abstract : Recent studies suggest a severe decline in yellow-legged gull populations across much of their distribution range. Already by the mid 2010s, the Basque coast was found to suffer declines of nearly 50% as compared to the global census conducted in 2007. After repeating the census in 2021, the aim of this study is to (1) update the population size of the breeding population of the yellow-legged gull on the Basque coast, (2) estimate its trend and (3) evaluate and update its conservation status. Overall, the population dropped from ca. 4200 adult breeding pairs during the first decade of the 21st century to 1861 pairs in 2021 (a 56% decline). There are a number of small colonies, especially around the Nervión river mouth, for which there was no data in 2021, so the actual population for that year may in fact be slightly higher. We also detected regional differences. In Gipuzkoa, the population was observed to decrease just 6%, whilst in Bizkaia the decline was 82%. The number of colonies also declined overall, from 27 colonies during the first decade of the 21st century to 24 in 2021. Moreover, the number of colonies with more than 100 pairs was found to decline from 10 during the first decade of this century to 4 in 2021. Overall, it must be emphasised that the main colonies existing in Bizkaia during the decade of 2000 are now in decline or have disappeared (e.g., Lekeitio, Izaro and Aketx), whilst the most eastern colonies located in Gipuzkoa seem to remain stable, hence Ulia is now the main yellow-legged gull colony of the Basque coast. Another interesting aspect is the creation of colonies around the Nervión river mouth, within the so-called Gran Bilbao. Should this steep decline continue, the species may become rare as a breeding bird in many areas along this coast, and may even be considered as being almost threatened.