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Expanding our knowledge of the nesting sites of Northern Storm-Petrels (Hydrobatidae) in northern Chile is a first step in determining their vulnerability to actions that affect their population dynamics. Globally, the Markham's Storm-Petrel (Hydrobates markhami) and the Ringed Storm-Petrel (H. hornbyi) are categorized as Near Threatened. In the Atacama Desert, previous research reported their use of flat areas devoid of vegetation as nesting microhabitat, where they take advantage of cavities in dry soil to breed. We report a new breeding colony and describe the nest attendance patterns of 2 storm-petrels in the vicinity of a fog oasis with the abundant vegetation characteristic of the hill formations of the coastal Atacama Desert, which constitutes a new nesting microhabitat for these species. Our adult nest attendance records document a daily pattern of nocturnal activity, where parents depart from nests in search of food before dawn and return during the night. The discovery of this new microhabitat for 2 endangered birds supports the protection of fog oases in the Atacama Desert, an ecosystem facing substantial threats. Ampliar nuestro conocimiento sobre los sitios de anidación de especies de petreles de tormenta o paíños (Hydrobatidae) en el norte de Chile es un primer paso para determinar su vulnerabilidad ante acciones que afecten su dinámica poblacional. A nivel mundial, el petrel de Markham (Hydrobates markhami) y el petrel de collar (Hydrobates hornbyi) se clasifican como casi amenazados. En el desierto de Atacama, investigaciones previas reportaron el uso de áreas planas desprovistas de vegetación como microhábitat de anidación, donde aprovechan las cavidades del suelo salino para reproducirse. En este reporte, describimos una nueva colonia reproductiva y analizamos los patrones de asistencia al nido de 2 especies de petreles en las cercanías de un oasis de niebla, con abundante vegetación característica de estas formaciones costeras del desierto costero de Atacama, lo que constituye un nuevo microhábitat de anidación para estas especies. Nuestros registros de asistencia a nidos de adultos documentan un patrón constante de actividad nocturna, donde los padres salen de los nidos en busca de comida antes del amanecer y regresan durante las primeras horas de la noche. El descubrimiento de este nuevo microhábitat para dos aves en peligro de extinción a nivel nacional sustenta la protección a la cual deben someterse los oasis de niebla en el desierto de Atacama, un ecosistema que enfrenta amenazas importantes. Palabras clave: crianza, ecosistema árido, especie en peligro, oasis de niebla. [ABSTRACT FROM AUTHOR]

As the fastest declining pinyon-juniper bird species, the Pinyon Jay (Gymnorhinus cyanocephalus) has generated considerable interest and conservation concern. The Pinyon Jay is named for its mutualistic relationship with pinyon pines (Colorado pinyon [Pinus edulis], single-leaf pinyon [P. monophylla]). Pinyon Jays are critical to the establishment and maintenance of pinyon-juniper woodlands impacted by climate-related drought, fire, and insect outbreaks, a role that may be compromised by the birds' declining abundance. Management for Pinyon Jays is an urgent need, and an improved understanding of their habitat ecology is a priority. Although Pinyon Jay social behavior has been well studied for decades, only recently has the habitat ecology of Pinyon Jays been investigated and only in New Mexico, the Great Basin, and the Colorado Plateau. Knowledge gaps remain, and less is known in other areas. Here we assemble and integrate information on Pinyon Jay habitat ecology from a diverse set of sources. Received 23 October 2022. Accepted 11 May 2023. Al ser la especie de ave en asociación con piñones y juníperos que está en declive más pronunciado, la chara piñonera (Gymnorhinus cyanocephalus) ha generado interés considerable y preocupación por su conservación. La chara piñonera recibe su nombre por su relación mutualista con los pinos piñoneros (piñón de Colorado [Pinus edulis], piñón de una sola hoja [P. monophylla]). Las charas piñoneras son críticas en el establecimiento y mantenimiento del arbolado de pino- junípero impactados por las sequías relacionadas al cambio climático, el fuego y los brotes de insectos, un papel que podría estar en peligro por el declive de abundancia de las aves. El manejo de chara piñonera es una necesidad urgente y mejorar la comprensión de su papel ecológico en el hábitat es una prioridad. A pesar de que el comportamiento social de la chara piñonera ha sido bien estudiado por décadas, no ha sido hasta hace poco que se ha empezado a estudiar el hábitat ecológico de la chara piñonera y este estudio se ha limitado a New Mexico, el Great Basin y el Colorado Plateau. Quedan vacíos de conocimiento y se conoce menos en otras áreas. Aquí unimos e integramos información de la ecología del hábitat de la chara piñonera de diversas fuentes. Palabras clave: ámbito hogareño, colonia de anidamiento, escala, nido, piñón-junípero. [ABSTRACT FROM AUTHOR]

The article presents the discussion on Annual Meeting of the Wilson Ornithological Society (WOS) held from 15–19 April 2021 in joint session with the Northeast Natural History Conference (NENHC) and the Association of Field Ornithologists (AFO). Topics include networking sessions, a career panel, pre-college student activities, career mentoring for students, and early professionals; and studying a wide range of topics in the natural history sciences.

The article discusses benefits of alloparental care in Great Tits (Parus major). It mentions efforts at a nest during an ongoing breeding season increase the parents' future survival and reproductive success rates; and also mentions Alloparents may get the benefit of acquiring practice before their own breeding and help increase their success in the next breeding season.

An introduction is presented in which the editor discusses articles in the issue on topics including satellite tracking; climate change; and shorebird conservation.

The article explores adult animals across many taxa use appeasement signaling to minimize or avoid costly conflict in social settings by jointly communicating their consent to defer and an interest to remain. When foraging, however, appeasement may not be enough to gain access to a resource controlled by a dominant conspecific.

The article explores the Least Tern (Sternula antillarum) commonly breeds along coastal beaches and major interior rivers of North America and the Caribbean. Least Terns have been observed in Hawai‘i since the 1970s; however, few breeding attempts have been documented. Nests have been discovered on the northwestern Hawaiian island of Midway Atoll and the southeastern Hawaiian island of Hawai‘i.

This study presents breeding phenology, fledgling production, and nest success for the Black Swift (Cypseloides niger) over a 22 year period at the Box Canyon colony, Ouray, Colorado, USA. Data were collected annually from 1996 to 2017 by direct observation from arrival of the birds at the nesting colony until all adults and fledglings departed. We documented dates of first arrival, laying, incubation onset, hatching, and fledging, and determined the intervals from arrival to laying, laying to incubation, length of incubation, and length of the nestling period in each year. Breeding events followed each other closely and showed little chronological change throughout the study. We identified a negative trend in the number of nest attempts and fledged Black Swift chicks over time but found no relationship between these 2 trends and the environmental factors of summer temperature, summer precipitation, or tourist visitation. The Mayfield estimate of nest success for all nest attempts was 77.5%. There was unexplained annual variation in nest success, but the trend in nest success remained static, with no correlation between nest success and temperature, precipitation, or tourist visitation. This study represents the largest dataset and longest-duration investigation into the breeding phenology and nest success of the Black Swift. [ABSTRACT FROM AUTHOR]

Cities are constant-expanding novel ecosystems that present multiple pressures for birds, but they can offer opportunities for generalist taxa with traits that ease their establishment. The Crested Oropendola (Psarocolius decumanus) is a Neotropical blackbird that nests colonially in different environments, from mature lowland forest edges to cultivated clearings, including other human-altered ecosystems. Here, we aim to characterize Crested Oropendola colonies in Caracas, Venezuela, a city where these birds have become more common in recent years. During 3 years (2016–2018), we recorded the number of complete nests per colony and tested for differences in colony size based on site characteristics and urban features. Additionally, we did multivariate ordinations (NMDS) to detect associations between such features and colony size, as well as spatial autocorrelation tests for size and change in the number of nests across years. By 2018, we recorded 45 colonies with 317 nests in Caracas (mean = 7), the largest quantity of oropendola colonies found in any locality until now. We report for the first time evidence of solitary nesting behavior and show that colonies placed in multiple trees were fairly common (29%). Colony size was not related to most nesting site features, with the exception of presence of nearby roads. Colonies close to roads showed significantly larger sizes than colonies far from them, potentially due to their isolation from predators. The mean distance between colonies was 1.1 km and we detected a slight negative spatial autocorrelation in nest change among neighboring colonies. We pinpoint differences in colony size and nesting patterns among Psarocolius species, likely related to different degrees of polygyny. Finally, we discuss the potential relationship of coloniality and isolated nesting sites, among other factors, in facilitating the establishment of this species in the city. The Crested Oropendola population in Caracas offers an opportunity to investigate reproductive and social aspects of the species and the evolution of colonial icterids. [ABSTRACT FROM AUTHOR]

We studied the nesting ecology of White-faced Ibis (Plegadis chihi) at 3 sites within the Bear River Migratory Bird Refuge, Great Salt Lake, Utah, USA. Ibises built nests in small mounds (mean height ¼ 14.4 6 4.3 cm) above shallow water (mean depth¼12.0 6 6.6 cm) located within patchy vegetation (mean percent vegetative cover¼17.2 6 17.8% vegetative cover) with mean vegetation height of 31.7 6 9.8 cm. White-faced Ibis typically laid a clutch of 3 or 4 eggs (mean clutch size¼3.08 6 0.76) and initiated nests over a 50 d period between 24 April 2012 and 12 June 2012. Mean nest success was 38% (95% CI: 31–45%) and hatching success of eggs from successful nests was 76 6 26%. Although most of the breeding parameters estimated for White-faced Ibis nesting in Utah were comparable to other populations in Oregon and Idaho (USA), nest success may now be lower than has been historically documented. [ABSTRACT FROM AUTHOR]

Fraser Darling suggested that reproductive synchrony enhances reproductive success of colonial seabirds as a result of predator satiation. However, the cost of yearly reproductive synchrony is high for colonial species for which intraspecific predation is the primary cause of egg and chick loss. A few studies indicate that egg-laying synchrony on a daily time scale within the annual breeding pulse may be an adaptive response to intraspecific predation. Here, we report every-other-day clutch-initiation synchrony in densely nesting cohorts of Ring-billed Gulls ( Larus delawarensis). This is the second known case of clutch-initiation synchrony on a daily time scale in larids, the first being for Glaucous-winged Gulls ( L. glaucescens). In both Ring-billed Gulls and Glaucous-winged Gulls, the degree of clutch-initiation synchrony is inversely related to nearest neighbor distance. Further studies are needed to test whether clutch-initiation synchrony in Ring-billed Gulls is adaptive in the presence of cannibalism, or if it is simply a neutral byproduct of colonial nesting. [ABSTRACT FROM AUTHOR]

Flightless Cormorants (Phalacrocorax harrisi), the only flightless members of their 27-member genus, are listed as vulnerable on the International Union for Conservation of Nature (IUCN) Red List. The world population of <1,000 breeding pairs is restricted to scattered small colonies along the coastlines of Isla Fernandina and Isla Isabela, Galápagos, Ecuador. No previous study has systematically examined daily activity patterns by these birds in relation to environmental variables. We made half-hourly behavior scan counts at a colony of Flightless Cormorants at Cabo Douglas, Isla Fernandina during the daylight hours of 7 consecutive days in May 2011. We used generalized linear models and multi-model inference to examine the response of colony occupancy and behaviors to hour of day, height of tide, temperature, humidity, wind speed, barometric pressure, solar elevation, and solar flux. We show that the behavior of Flightless Cormorants during our period of study was shaped primarily by time of day, wind speed, and solar flux; unlike many marine birds, they responded little to tide. [ABSTRACT FROM AUTHOR]

Enhanced vigilance against prédation is often an advantage of living in groups, but most studies have not examined individual-specific variation in the propensity to be vigilant among the animals within a group. We studied vigilance at the nest in colonially nesting Cliff Swallows (Petrochelidon pyrrhonota) in southwestern Nebraska in 2011 and 2012, and asked whether differences among individuals were consistent over time, whether vigilance varied among different colonies, and whether there were positive or negative fitness consequences of different levels of vigilance. We found significant among-individual variation in extent of vigilance and some variation among different colony sites. Vigilance also varied with date and nesting stage, but other phenotypic characteristics of a bird had no effect on vigilance. Differences among individuals in vigilance were not strongly related to their reproductive success that season, but more vigilant individuals were more likely to attempt intrusions into their neighbors' nests. Vigilance at the nest may be partly directed at monitoring conspecifics' activities in neighboring nests. This study is among the few that have investigated individual variation in vigilance behavior, a possible index of personality for Cliff Swallows, and the first to measure variation in vigilance for a colonial bird while breeding. [ABSTRACT FROM AUTHOR]