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Nuevo sitio de anidación de la golondrina marina piquigruesa (Gelochelidon nilotica), en el centro de Sinaloa, noroeste de MéxicoDescubrimos un nuevo sitio de anidación para la golondrina marina piquigruesa (Gelochelidon nilotica)en la región central de Sinaloa, México. Registramos la presencia de esta especie en una salina abandonada en la Bahía de Ceuta desde el 2004. Registramos su anidación en 2006, un adulto incubando entre varios nidos de charrán mínimo (Sternula antillarum). Nuestra observación indica que a pesar de la intensidad de los monitoreos de Palacios y Mellink, el inventario de colonias de la golondrina marina piquigruesa en el oeste de México no ha sido terminado completamente, y algunas colonias pequeñas aún pueden ser encontradas.

The taxonomic status of the gerbil Gerbillus amoenus in relation to Gerbillus nanus and the distribution range of these two species in Africa and/or Asia have long been debated and are not yet fully clarified. In our study, we identify two specimens of small gerbils that we captured in two localities of the south of Morocco, using morphometric and/or molecular tools. The body and skull measurements were not able to unambiguously discriminate between three closely related small gerbils (Gerbillus amoenus, Gerbillus nanus and Gerbillus henleyi). However, the cytochrome b gene analysis showed that our two specimens cluster unambiguously with haplotypes of G. amoenus. This represents the first genetic characterization of G. amoenus in Morocco. It confirms, based on mitochondrial DNA, that the previously described species living in Africa is indeed G. amoenus and not G. nanus, the latter species being present strictly in Asia.

The breeding distribution of the Gull-billed Tern Gelochelidon nilotica in Algeria is poorly known as the species is mainly associated with highly unstable habitats. We conducted a survey of the distribution of the species across all major Algerian wetlands and monitored a breeding colony at El Goléa during 2009. The species is usually described as a passage migrant in the Sahara, but its status may have to be reconsidered following our discovery of a small colony nesting on an islet in Sebkhet El Maleh, El Goléa. The colony consisted of 25 birds which built nine nests and foraged exclusively in and around the salt lake. Laying of eggs began in mid-April, in synchrony with high temperatures and strong evaporation. Clutches varied between 1 and 3 eggs but none was successful. The gradual drop in water level and subsequent drying of the Sebkha coincided with the first hatchings, exposing the first hatchlings to mammalian predation arising from the intrusion of jackals Canis aureus, which entirely destroyed the colony.

Background Coastal saltpans are a common supratidal human-modified wetland habitat found within many coastal landscape mosaics. Commercial salt production and aquaculture practices often result in the creation of exposed coastal substrates that could provide suitable breeding habitat for waterbird populations; however, few studies have quantified waterbird breeding success in these artificial wetlands. Methods Here we examine the nesting behavior of the Gull-billed tern (Gelochelidon nilotica) breeding in the Nanpu coastal saltpans of Bohai Bay, Yellow Sea, China over three consecutive nesting seasons (2017–2019) by using nest survival model in Program MARK. Results The results revealed that nest survival of Gull-billed terns in coastal saltpans (0.697) was higher than previously published estimates from other regions, with an estimated daily survival rate (DSR) of 0.982 ± 0.001 (±95% CI). High nest survival was mainly attributed to low levels of human disturbances and low predation rates, while exposure to strong winds, flooding and silting were the main factors causing nest failure. Model-averaged estimates revealed that eggs laid in nests located on ‘habitat islands’ with feather or clam shell substrates were most likely to hatch. Initiation date, nest age, clutch size and quadratic effects of nearest-neighbor distance, nearest distance to road and nearest distance to water were all significant predictors of nest success, but the nest survival declined overall from 2017 to 2019 due to the degradation and loss of breeding habitat anthropogenically caused by rising water levels. Discussion Coastal saltpans represent an alternative breeding habitat for the Gull-billed tern populations in Bohai Bay, but conservation management should prioritize flood prevention to improve the extent and quality of breeding habitat, concurrent with efforts to create further ‘habitat islands’ with suitable nesting substrate.

Here we report the first documented records of the Gull-billed Tern, Gelochelidon nilotica (Gmelin, 1789), from Rio de Janeiro state, on the coast of southeastern Brazil. The species was recorded in Sepetiba Bay, in Rio de Janeiro municipality, in August and September 2014 and September 2015. In all cases, the birds had full nuptial plumage, which suggests breeding in the austral spring and summer. This is inconsistent with the possibility of a migrant from the Northern Hemisphere. The regular monitoring of the coastal environments of this region should provide more conclusive insights into seasonal patterns and the migration routes of this species.

Eggshell pigmentation has been assessed as an indicator of exposure to environmental pollutants in birds, but these studies have only used reflectance spectrophotometry to measure such pigmentation. The present study is the first one that measures eggshell pigments and pollutants in the same eggs to explore their use as biomarkers in birds. We have studied the concentration of organochlorine pesticides and polychlorinated biphenyls (PCBs) in the content of 97 deserted eggs of gull-billed terns (Gelochelidon nilotica) after the abandonment of the colony in Mesas de Asta (Cádiz, S Spain) in 2012. Eggshell thickness and stage of embryo development were studied together along with the concentrations of protoporphyrin IX and biliverdin in eggshells. p,p′-DDE concentrations were high when compared with other studies done with terns in the Mediterranean basin in the past. p,p′-DDE and PCB levels associated with reduced reproductive success were found in 5.1% and 2.1% of the eggs respectively. Eggshell index was largely affected by the embryo development stage, which highlights the need of knowing this information to avoid potential biases in the interpretation of results. The concentrations of protoporphyrin IX and biliverdin in the eggs of gull-billed terns were negatively associated with DDTs levels, which seems to confirm previous observations with phylogenetically related species., University of Castilla-La Mancha funded the analysis of samples with project CGT13-0183. Pablo R. Camarero benefited from a contract with reference PTA2017-14583-I financed by the Spanish Ministry of Economy and Innovation and CSIC.

Selección del hábitat alimentario de la pagaza piconegra (Gelochelidon nilotica) en el centro de España (Castilla–La Mancha) La pagaza piconegra se reproduce en lagos temporales de Castilla–La Mancha, pero depende de los hábitats terrestres de los alrededores para alimentar a los pollos. Por consiguiente, es fundamental conocer el tipo de ambientes que selecciona para capturar presas con las que alimentarlos. La finalidad de este estudio fue evaluar la utilización que los adultos de la pagaza piconegra hacen de los hábitats para la caza. De los 66 lagos estudiados entre 1996 y 2016, constatamos que la pagaza se reproducía en 12. Durante este período, cada lago se utilizó para 1–14 temporadas de cría. Seleccionamos las zonas circulares alrededor de los tres humedales en los que la especie crio en 2013 y 2014. Dentro de estos círculos, muestreamos 60 puntos aleatorios y registramos 125 contactos con pagazas piconegras (incluidas entre 1 y 39 aves). Estimamos las mismas variables ambientales en los puntos de contacto y los aleatorios, con inclusión del uso de la tierra y la distancia al humedal más cercano, a la colonia más cercana y a varios tipos de usos antrópicos (carreteras asfaltadas, viviendas y ciudades). Para evaluar la selección del hábitat, calculamos el índice de selección de Manly para las variables de uso del suelo y utilizamos modelos lineales mixtos para evaluar las diferencias entre las variables de distancia. El principal uso de la tierra que la pagaza piconegra seleccionó para la alimentación fue el cultivo de cereales, mientras que evitó los viñedos. De media, las aves se alejaron para alimentarse hasta 2 km de las colonias y tendieron a evitar la proximidad de ciudades y carreteras asfaltadas, lo que sugiere que la especie es sensible a las perturbaciones antrópicas. Los viñedos constituyen el principal uso de la tierra en esta región y su intensidad está aumentando. Nuestros resultados sugieren que los viñedos se deberían limitar en zonas cercanas a estos humedales, para que la pagaza piconegra pueda alimentarse en sus lugares preferidos., The gull–billed tern breeds in temporary lakes in Castilla–La Mancha in Central Spain but depends on surrounding land habitats to feed its chicks. It is therefore vital to know the type of environments it selects to capture prey to feed nestlings. The aim of this study was to evaluate the use of habitats for hunting by adult gull–billed tern. Of 66 lakes monitored between 1996 and 2016, we found the gull–billed tern used 12 for breeding. Each lake was used during this period for 1–14 breeding seasons. We selected circular areas around the three wetlands where the species bred in 2013 and 2014. Within these circles, we sampled a total of 60 random points and recorded 125 gull–billed tern contacts (including between 1 and 39 birds). We estimated the same environmental variables at contact and random points, including land use and the distance to the nearest wetland, the nearest colony and to several types of anthropic uses (paved roads, houses, and cities). To evaluate habitat selection we calculated the Manly selection index for soil use variables, and fitted linear mixed models to evaluate differences in the distance variables. Land uses selected for foraging by the gull–billed tern were mainly cereal crops, whereas vineyards were avoided. The birds foraged on average up to 2 km from the colonies and tended to avoid proximity of towns and paved roads, suggesting that the species is sensitive to human disturbance. Vineyards are the main land use in this region and the intensity is increasing. Our results suggest vineyards should be limited in areas around these wetlands so that gull–billed terns may forage in their preferred sites.

We report new nesting sites for the Van Rossem’s Gull-billed Tern (Gelochelidon nilotica vanrossemi) at the Agua Dulce and Xola-Paramán lagoons, in the coast of the state of Jalisco, Mexico. We first recorded the nests on 19 June, 2013 and monitored them at two-week intervals until 2 August, 2013. We found eight nests in the Agua Dulce lagoon and 16 in the Xola-Paramán lagoon. These new records expand the known nesting range of the Van Rossem’s Gull-billed Tern along the Pacific coast, from San Diego, California to the state of Colima in Mexico.

North American populations of Gull-billed Terns (Gelochelidon nilotica) are thought to winter in low numbers throughout Central America, with highest single-site concentrations of up to 200 individuals known from the Panama Canal zone. This paper presents information on a previously unknown stopover and wintering site in southern Honduras, where up to 1,640 individuals, approximately 20% of the entire North American metapopulation, are present during the non-breeding season. This site may be of key importance to full cycle conservation of declining North American populations. Information on habitat use in the eastern Gulf of Fonseca is also included.

Albano N., Masero J.A., Sanchez-Guzman J.M., Villegas A. & Santiago-Quesada F. 2011. Effects of diet on growth-related patterns of energy and macronutrient assimilation efficiency in a semi-precocial bird, the Gull-billed Tern Gelochelidon nilotica. Ardea 99: 93–101.

During the 2003 and 2005 breeding seasons we conducted ground surveys of historical, potential, and current nesting sites of the VanRossem’s Gull-billed Tern (Gelochelidon nilotica vanrossemi) along the Pacific coast of Mexico. We documented 13 active colonies, including ten previously unrecorded nesting sites. One previously reported colony was inactive. Colony sizes ranged between one and 161 breeding pairs. In 2005, the estimated breeding population size was 526 pairs. Eighty-two percent of the total breeding population was concentrated in three relatively large colonies, Cerro Prieto and Isla Montague, Baja California and Laguna Las Garzas, Nayarit. Gull-billed Terns nested mostly on islets in very shallow waters. Colony associates included other terns, Black Skimmers (Rhynchops niger), gulls, and egrets. The nesting population of this subspecies in Mexico is very small and consists of a few widely separated colonies. This subspecies should be included in Mexico’s official list of species at ...

Around forty bird species habitually reproduce in the Northern Hemisphere during summer, and migrate to the Southern Hemisphere during northern winter. These migrating birds fly together in large or small groups until they have reached the Caribbean, Central American, or Brazilian shores. Charadrius semipalmatus, Bonaparte 1825, is one of these migrating species that uses resting and feeding areas along eastern and western coasts of North and South America, with several records for the Brazilian coast, and very few for the inland country. On November 24, 2011, an individual of this species was observed on the banks of one of the lakes that compose a complex of about 40 temporary lakes within the Karst of Lagoa Santa Environmental Protection Area. On October 29 and 30, 2012 a single individual of Gelochelidon nilotica, Gmelin 1789, was also observed in Sumidouro State Park. We suggest that these specimens have used the Atlantic Ocean migration route, following the São Francisco River Basin, until the karst area. Although highly impacted, the temporary lakes within the Karst of Lagoa Santa still harbor a significant number of bird species, and serve as resting and feeding places for migratory or errant species that are still eliciting new records. Cerca de 40 espécies de aves se reproduzem no hemisfério Norte durante o verão e migram durante o inverno, desse hemisfério, para o hemisfério Sul. Essas aves migratórias se reúnem em grandes ou pequenos bandos até atingir o Caribe, América Central e região costeira do Brasil. Charadrius semipalmatus, Bonaparte 1825, é uma das migratórias que usa áreas de repouso e alimentação ao longo das costas leste e oeste das Américas do Norte e do Sul, tendo vários registros no litoral brasileiro e muito poucos no interior do país. No dia 24 de novembro de 2011, um indivíduo da espécie foi observado nas margens de uma das lagoas que compõem um complexo de cerca de 40 lagoas temporárias da Área de Proteção Ambiental (APA) Carste de Lagoa Santa. Nos dias 29 e 30 de outubro de 2012 um indivíduo de Gelochelidon nilotica, Gmelin 1789, foi observado na lagoa do Sumidouro, no Parque Estadual do Sumidouro. Sugerimos que os indivíduos utilizaram a rota do Oceano Atlântico para a migração, seguindo a bacia do rio São Francisco até atingir a área da APA Carste de Lagoa Santa. Apesar de altamente impactadas, as lagoas temporárias da APA Carste de Lagoa Santa ainda abrigam expressiva riqueza em espécies e servem como local de repouso e alimentação para espécies migratórias ou errantes ocasionais que continuam sendo registradas.

Gull-billed Tern Gelochelidon nilotica is classed as Endangered in Europe (Tucker and Heath 1994, Hagemeijer and Blair, 1997), but there have been no detailed studies of the trends in the different populations occurring in Europe and Africa. Here we study the status and trends of the species in Europe and north and north-east Africa. We estimate the total population at 10,500–12,900 breeding pairs, and recognize two biogeographical populations in this region. The western population, comprising colonies in northern Europe (Denmark, Netherlands, Germany), France, Italy, Spain, and north and north-east Africa, consists of at most 6,200 pairs, 1,800 of which are in African colonies. The eastern population, comprising colonies in the Balkan Peninsula, Greece, shores of the Black Sea and Sea of Azov, and Turkey, consists of at most 6,800 pairs. Two trends were observed: a first phase from 1900 up to the mid-1970s in which the northern European populations practically disappeared; and a second phase of stabilization, or even increase, in some of the western colonies, while the eastern population continued to decline. There is a marked concentration of the species in just a few localities in the countries of the Mediterranean basin.

Around forty bird species habitually reproduce in the Northern Hemisphere during summer, and migrate to the Southern Hemisphere during northern winter. These migrating birds fly together in large or small groups until they have reached the Caribbean, Central American, or Brazilian shores. Charadrius semipalmatus, Bonaparte 1825, is one of these migrating species that uses resting and feeding areas along eastern and western coasts of North and South America, with several records for the Brazilian coast, and very few for the inland country. On November 24, 2011, an individual of this species was observed on the banks of one of the lakes that compose a complex of about 40 temporary lakes within the Karst of Lagoa Santa Environmental Protection Area. On October 29 and 30, 2012 a single individual of Gelochelidon nilotica, Gmelin 1789, was also observed in Sumidouro State Park. We suggest that these specimens have used the Atlantic Ocean migration route, following the São Francisco River Basin, until the karst area. Although highly impacted, the temporary lakes within the Karst of Lagoa Santa still harbor a significant number of bird species, and serve as resting and feeding places for migratory or errant species that are still eliciting new records.