Ornitología Neotropical (E-Journal)
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INSIGHTS INTO THE HABITS OF THE ELUSIVE NOCTURNAL CURASSOW (NOTHOCRAX URUMUTUM)
Get PDFNocturnal curassows (Nothocrax urumutum) are one of the most enigmatic birds from South American rainforests. Their elusive habits and their nocturnal vocal behavior have led to the generalized assumption that they differ from other curassows in their presumable nocturnal habits. Here, we compiled camera trap data from long term projects in the Amazon rainforest and the Andes Cordillera piedmont to describe the temporal activity of Nocturnal Curassows. Based on an overall sampling effort of 68838 camera nights we obtained 274 independent records of their activity. The results of this study evidence that Nothocrax has diurnal habits and resembles in activity patterns to all other cracids more than previously expected. This study highlights the use of novel technologies and collaborative research towards the understanding of the natural history, ecology and behavior of animals with cryptic behaviors such as the Nocturnal Curassows
NOTES ON THE DIET OF THE STRAIGHT-BILLED EARTHCREEPER (OCHETORHYNCHUS RUFICAUDUS) AND THE USE OF CITIZEN SCIENCE IMAGE REPOSITORIES
Get PDFHere we report on novel information regarding the diet for the Straight-billed Earthcreeper (Ochetorynchus ruficaudus), an uncommon furnarid of arid environments of the Andes. We describe an event of food consumption in northern Chile, and complement our finding by searching freely-available citizen science repositories for photographic evidence of food items. Novel food items belonging to Coleoptera and Lepidoptera were identified. These findings contribute to our understanding of the natural history of an uncommon species, making use of opportunistic photography and freely-available and ever-increasing citizen science data
URBAN SOUTHERN HOUSE WREN (TROGLODYTES MUSCULUS) NESTING IN APPARENTLY UNSUITABLE HUMAN-MADE STRUCTURES: IS IT WORTH IT?
No full textFree-living birds in cities interact with humans and human-made objects. Here, we investigated whether nesting in human-made structures that are physically unstable and prone to frequent human intervention benefits urban Southern House Wrens (Troglodytes musculus). First, we describe the behavior of individuals that repeatedly attempted to nest in a motorcycle helmet (an unsuitable structure) based on ad libitum observations and camera trapping. We also reviewed nesting records of this wren throughout Brazilian cities deposited in crowdsourcing citizen science platforms, such as Wiki Aves, eBird, and iNaturalist. During our field study, in November and December 2019, wrens attempted to build a nest in the helmet for 8 days. Each attempt was interrupted by the removal of the helmet. We recorded 103 videos of nesting activity, including 3 days of high nest-building effort (up to 68 twigs deposited inside the helmet within a 6-h period) and high territory-defense efforts. Both of these behaviors were sometimes followed by one of four types of vocalizations (contact call, complete song, incomplete song, or sub-song). We found 372 Southern House Wren nesting records in online citizen science datasets: 100 were in urban areas with 86 nests built on 24 different human-made structures. Most nests (n = 71) were in what we deemed as stable structures (safe from human intervention) and 34 of them (47.8%) likely bred successfully (i.e., fledglings present). Only seven nests were built on unstable and unsafe structures, and four (57.1%) of these had sufficient evidence of successful nesting. Although nesting in unsuitable places in cities is less-frequent, their breeding success is comparable with nesting in suitable places. Therefore, the nesting of Southern House Wren in human-made structures might benefit the species, even if they eventually become ecological traps due the risk of human intervention. Our study adds knowledge about the life history of the species in urban environments
INDEPENDENT OBSERVATIONS OF PHAEOMELANIC MALES OF THE VARIABLE SEEDEATER (SPOROPHILA CORVINA) WITH COMMENTS ABOUT ITS POTENTIAL FOR EVOLUTIONARY DIVERGENCE
Get PDFPlumage coloration largely depends on the type and concentration of pigments present in feathers. Therefore, changes in pigment deposition may result in aberrant colorations, which, in turn, will likely interfere with the plumage color’s function (e.g., signaling, protection). Published records of aberrant plumage colors underestimate the type and frequency of these phenotypes, especially in the tropics. Here, we report five independent observations of phaeomelanic males of the Variable Seedeater (Sporophila corvina), in which typically white feathers were instead chestnut-red, likely due to the deposition of phaeomelanin. Our observations add to previous reports of aberrant melanin-based coloration in this species, suggesting that genomic region(s) influencing the expression of phaeomelanin are a biased target for mutations. Because mutations affecting the regulation of melanin deposition result in novel plumage phenotypes, we discuss aberrant phenotypes as an important source of variation fueling rapid divergence among populations of this avian clade
NESTING OF THE YUCATAN VIREO, VIREO MAGISTER, IN MAINLAND MEXICO AND ON ISLA COZUMEL, WITH DETAILS OF BREEDING PHENOLOGY
No full textWe report the first definitive Mexican breeding records of the range-restricted Yucatan Vireo (Vireo magister). We discovered two V. magister nests in July and August 2009 in Sian Ka’an Biosphere Reserve (near Tulum) and one nest on Isla Cozumel in June 2009. We observed two possible additional V. magister nests with eggs in Sian Ka’an in 2009, one each in June and July. All nests were open cups woven onto branches and hung beneath forks. Clutch size was two eggs at definitive V. magister nests. Nests and eggs were similar to those of most Vireo spp., including sympatric nesting congeners. Breeding activities—including egg-laying, incubation, and nestling and post-fledging provisioning—at definite Yucatan Vireo nests occurred in June and July on Cozumel and July and August on the mainland. Incubation and nestling stages lasted ~ 15 days and ~ 14 days, respectively. Yucatan Vireo remains poorly known, warranting further study
CONTRIBUTION OF INFORMAL GREENSPACE TO BIRD CONSERVATION IN CITIES: A COMPARATIVE STUDY ON THE DIVERSITY OF BIRD COMMUNITIES IN VACANT LANDS, URBAN PARKS AND RESIDENTIAL AREAS
Get PDFVacant lands are part of the informal greenspace and could maintain native fauna in urban ecosystems. To provide scientific evidence that promotes bird conservation in cities, we compared different bird community attributes among vacant lands, urban parks, and residential areas in the city of Santiago de Chile. For this, we estimated taxonomic diversity in the three land uses, investigated the species richness and abundance (total and native, including three trophic guilds: granivores, insectivores and omnivores) among land-use types, and evaluated the influence of habitat variables on bird species richness and abundance recorded at sites. We found that vacant lands supported a diverse, with low species dominance, species rich and abundant bird community, comprised mainly by native granivorous and insectivorous birds. In contrast, birds with generalist diet (omnivores) reached high abundances in urban parks and residential areas. While parks and residential areas were dominated by a single omnivore species (Turdus falcklandii and the exotic Passer domesticus, respectively), in vacant lands a set of native species reached high abundances. They included granivorous birds (Sicalis luteola, Zenaida auriculata y Zonotrichia capensis) and insectivorous birds (Tachycineta meyeni y Anthus correndera). Sites with larger cover of herbaceous plants exhibited greater richness and abundance of native birds. In addition, sites with larger proportion of their area covered by bare ground exhibited greater abundance of native birds. Our results demonstrate that vacant lands maintain high bird diversity, as well as a high species richness and abundance of native birds with specialized diets (granivores and insectivores), offering new opportunities to conserve biodiversity in cities
UN RARO CASO DE ENCANECIMIENTO PROGRESIVO CON EXPRESIÓN DE XANTOCROISMO EN EL CACIQUE MEXICANO (CASSICULUS MELANICTERUS)
Get PDFResumen. Con el objeto de reportar un raro caso de encanecimiento progresivo con expresión de xantocroísmo en el cacique mexicano (Caciculus melanicterus) y su desarrollo en el tiempo, se tomaron fotografías anualmente entre 2018 y 2021 a un individuo de plumaje aberrante. En 2018 el ave mostraba simplemente una macha amarilla atípica en la cabeza que ocupaba un estimado del 5% de la superficie de su plumaje. Con el tiempo el color negro de sus plumas fue progresivamente sustituido por amarillo con ligera despigmentación en la cara y las alas. De manera que en 2019, la aberración se había extendido hasta abarcar aproximadamente el 50% de su plumaje y para 2020-2021 alcanzó el 75%. El presente reporte se trata del primer caso de este tipo conocido en el Neotrópico.Palabras clave: Aberración del plumaje, carotenismo, flavismo, pluma, xantocroismo
DESCRIPTION OF COLLARED TROGON (TROGON COLLARIS) NESTS IN THE SIERRA DE ZONGOLICA, VERACRUZ, MEXICO
No full textThere is relatively little information on nesting behavior of the collared trogon (Trogon collaris). In this study we describe three nests of this species and some characteristics of the nesting sites in the Sierra de Zongolica, Veracruz, Mexico
THE DEGREE OF FRUGIVORY OF BIRDS AS ESTIMATED FROM GASTRIC AND FECAL SAMPLES
Get PDFThe degree of frugivory (DF) has long been used to characterize the relative importance of fruits to the diet of a bird and, more recently, as a functional trait related to the role of birds in seed dispersal networks. Although quantitative estimations of DF are desirable, general, categorical classifications or coarse estimations of diet composition based in qualitative information are often used. Data on stomach, fecal and regurgitation contents scattered in the literature or easily obtained in the field could be used to provide a quantitative, potentially more reliable assessment of DF. We compiled such data from the literature and our own fieldwork to obtain 12,576 samples for 985 Neotropical bird species, of which 489 species (49.6%) from 61 families had at least one fruit-containing sample. Gastric (i.e. stomach plus regurgitation) and fecal samples provided similar estimates of DF, despite potential differences in the degree of food digestion. The DF we obtained were higher than those presented in the most frequently used source of quantitative DF estimates in the literature (the Elton Traits database). We further explored with a few study cases the utility of stomach, fecal and regurgitation samples to evaluate intraspecific geographic, sexual, and ontogenetic variations in DF, topics rarely investigated so far. We argued that stomach, fecal and regurgitation sample data abundantly available in the literature or obtained from mist-netted birds may be used to produce quantitative assessments of DF likely more reliable than the estimates used so far and useful for a plethora of ecological studies
NIDIFICACIÓN DENTRO DE CAVIDADES INÉDITA ENTRE FALCÓNIDOS: UNA POBLACIÓN DE CHIMANGOS (MILVAGO CHIMANGO) APROVECHANDO NIDOS DE LOROS BARRANQUEROS (CYANOLISEUES PATAGONUS) EN PATAGONIA ARGENTINA
No full textAbstract. Unprecedented cavity nesting among falconids: a Chimango Caracaras (Milvago chimango) population using Borruwing Parrots (Cyanoliseus patagonus) nests in Patagonia Argentina. The Chimango Caracara (Milvago chimango) is the most abundant member of raptor assemblages from Paraguay and Bolivia to the southern tip of Argentina. In Argentinian Patagonia we studied nesting and other biological aspects of a Chimango Caracaras population that exploits cavities built by marine psittacines, in a unique ornithological assemblage: 12 km of sea cliffs with 37,000 active nests of Burrowing Parrots (Cyanoliseus patagonus). During 56 days we assessed a total of 18 active Chimango Caracaras nests (11 in 2014 and 7 in 2015). All nests contained plant material inside and had some structure to facilitate landing and perching. Most were located in the upper third of the cliff and had a single entrance mouth. The average distance to the nearest nest in the same breeding season was 108.9 m ± SD 90.90 m. We document in detail for the first time the construction of Chimango Caracaras nests inside cavities. Our results document a new breeding substrate for this species and a nesting behaviour unique among falconids, which could be interpreted as evidence of adaptability and plasticity of Chimango Caracaras