In most Neotropical Psittacidae the existence and extension of long-distance movements are poorly understood. The Blue-and-yellow Macaw (BYM; Ara ararauna) has a wide range in South America and its ...occurrence seems to be seasonal or sporadic in some areas. This study describes the results of BYM data collected in a monthly regular field effort from July 2001 to June 2005 at the RPPN SESC Pantanal reserve (Mato Grosso state, Brazil). The aim of the study was to evaluate the BYM's use of the reserve resources, its displacements and possible causes. Every observed BYM flock or individual had its date, hour, geographic coordinates, flock size, and activity (landed, feeding, or displacement) registered. The flight azimuth of continuous and straight displacements was also registered. We used circular statistics and vector pairs (azimuth and flock size) to analyze the observed intraday, monthly, and yearly displacements pattern. A total of 189 flocks and 854 BYM were recorded, the average size being 4.5 ± 3.7 individuals per flock. The prevalent activity category was displacement (85.2 ± 3.8%) and the flocks occurred with non-uniform distribution through the year. Seventy one percent of all flocks were registered in only 4 months, each one with a statistically significant well-defined flight bearing direction pattern. The mean vector angles calculated for the January/February data (279°/288°) were the opposite of those obtained for the May/June data (98°/110°). The intraday data showed no change in the main flight direction pattern when morning and afternoon data were compared, indicating they were not night roosting/feeding areas movements. The same months through the 4 analyzed annual cycles had the majority of the records. This directional and repetitive pattern does not fit in circadian or nomadic displacements, but suggests seasonal movements of the BYM in the studied area. The observed directions, period, and seasonal direction change of flight paths are consistent with pre- and post-reproductive periods observed in the central region of Brazil. However, still unknown is their origin and destination, as well as the involved mechanisms.
The Black Skimmer (Rynchops niger) and the Large-billed Tern (Phaetusa simplex) are two migratory waterbirds that breed simultaneously on many river beaches in South America. Both are polytypic taxa ...with little information about the distribution and nonbreeding (“wintering”) areas. Based on data from the literature, citizen science websites, fieldwork, and specimens housed in natural history museums, we revised the distribution of some of the main breeding colonies in South America, comparing it with continental rainy cycles to identify generalities about the role of precipitation seasonality on the defining intratropical migration routes of these species. Our data suggest that the seasonal precipitation cycle of South America directly influences the reproductive timing and distribution of both species, which is largely circumscribed by South America’s rivers. After breeding on sandy beaches during the dry season, both species disperse in small groups or even individually – not in large flocks as seen in breeding areas – making it difficult to find general migration patterns during the rainy season. Nonetheless, individuals of both species tend to follow the course of the largest rivers of the continent and even alternative routes to disperse into several areas throughout South America during the nonbreeding season.
The Blue-throated Macaw (Ara glaucogularis) is a Critically Endangered species endemic to the Llanos de Moxos ecosystem of Beni, Bolivia. To aid conservation of the northwestern population that ...utilizes the Barba Azul Nature Reserve during the non-breeding season, we set out to learn the sites where these birds breed using satellite telemetry. We describe preliminary tests conducted on captive birds (at Loro Parque Foundation, Tenerife, Spain) that resulted in choosing Geotrak Parrot Collars, a metal, battery-operated unit that provides data through the Argos satellite system. In September 2019, we tagged three birds in Barba Azul with Geotrak collars, and received migration data for two birds, until battery depletion in November and December 2019. Our two migrant birds were tracked leaving Barba Azul on the same date (27 September), but departed in divergent directions (approximately 90 degrees in separation). They settled in two sites approximately 50–100 km from Barba Azul. Some details of the work are restricted out of conservation concern as the species still faces poaching pressures. Knowing their likely breeding grounds, reserve managers conducted site visits to where the birds were tracked, resulting in the discovery of breeding birds, although no birds still carrying a transmitter were seen then. A single individual still carrying its collar was spotted 13 August 2021 at Barba Azul. The work suggests that the Blue-throated Macaws of Barba Azul use breeding sites that are scattered across the Llanos de Moxos region, although within the recognized boundaries of the northwestern subpopulation. We conclude that the use of satellite collars is a feasible option for research with the species and could provide further conservation insights.
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•Brazilian Merganser has few suitable areas remaining for its three populations.•Several small hydroelectric plants are planned in areas where the species inhabits.•A high amount of ...suitable area used by the species is not within Protected Areas.•A fifth of the suitable areas are covered by anthropogenic land use, mainly pasture.•Brazilian Merganser situation is critical, calling for urgent conservation actions.
The critically endangered Brazilian Merganser Mergus octosetaceus is one of the rarest waterfowls in the world. Only three isolated populations remain in the Brazilian Cerrado, totaling less than 250 individuals. We evaluated the potential influence of small hydroelectric plants (SHPs) and Protected Areas (PAs) on the species’ conservation. We identified suitable areas by using recent presence records and environmental predictors, and overlapped it with the species dispersion zone and the SHP impact zone. Suitable areas for the species are limited to 4% of the geographic space (142,899km2). Within the dispersion zone, we found 36 planned SHPs, which can impact 4.1% of the suitable area and 17.2% of the suitable area inside PAs. Our results expose the critical situation of the Brazilian Merganser, with few isolated suitable areas, high potential impacts for the three known populations, and a high proportion of suitable areas out of PAs. We highlight the need of considering SHPs impacts on the Brazilian Merganser in environmental impact assessment studies to reduce them. Furthermore, we appointed areas for search of new populations, and emphasize how urgent the implementation of effective conservation actions aiming to protect the remaining suitable habitats for the Brazilian Merganser is.
Sociedade Brasileira de Ornitologia: a history Höfling, Elizabeth; dos Anjos, Luiz; Scherer-Neto, Pedro ...
Revista Brasileira de Ornitologia,
12/2017, Letnik:
25, Številka:
4
Journal Article
Janelas para entender a migração de aves Antas, Paulo de Tarso Zuquim
Revista de Fotografia Científica Ambiental,
10/2017, Letnik:
1, Številka:
1
Journal Article
During February and early March of 1995, Great Gull Island Project researchers surveyed the coasts of northern Argentina, Uruguay, and Brazil for wintering Roseate (Sterna dougallii) and Common ...(Sterna hirundo) Terns. We sighted both species on 6 March in a small flock off Alcobaça (17°33′S, 39°4′W) near Porto Seguro. This sighting of Roseates and the report of the recovery of a Great-Gull-Island-banded Roseate Tern at 18°00′S, 39°30′W on 24 Jan. 1995 provide the southernmost wintering records of the species to date. At Punta Rasa, Argentina, we found an estimated 20,000 to 30,000 Common Terns in early February. Although the species known range includes Argentina, this is the first report of such a large wintering concentration at this latitude. All color-banded Common Terns we saw in Argentina and southern Brazil, as well as all recovered banded birds from these areas, were over one year old. This suggests that older Common Terns occupy the more southern parts of the wintering range. Recoveries of Great Gull Island Common Terns from southern Brazil and Argentina made in April and May, and subsequently trapped on Great Gull Island, show that some birds make the >8000 km trip in 3 wk or less. /// Durante el mes de Febrero y los primeros días de Marzo de 1995, los investigadores del Proyecto Great Gull Island visitaron las costas de Argentina, Uruguay, y Brasil en busca de registros de invierno para el Gaviotín Rosado (Sterna dougallii) y el Gaviotín Común (S. hirundo). Ambas especies fueron observadas en pequeñas colonias en la costa de Alcobaça (17°33′S, 39°04′W), cerca de Porto Seguro el día 6 de Marzo. Los avistamientos de Gaviotín Rosado, junto con la recaptura de un individuo de Gaviotín Rosado anillado en la isla Great Gull el 24 de Enero de 1995, representan los registros invernales más australes para esta especie. Durante los primeros días de Febrero se calcula haber obervado entre 20,000 a 30,000 individuos de Gaviotín Común en Punta Rasa, Argentina. Aún cuando las costas Argentinas han sido consideradas como parte de la distribución normal de S. hirundo, este es el primer reporte de la existencia de grandes colonias invernales en esta latitud. Todos los individuos de Gaviotín Común con bandas de colores observados en Argetina y sur de Brazil, así como todas las recapturas realizadas en estas áreas de aves anilladas en la isla Great Gull, fueron mayores de un año de edad. Esto sugiere, que las aves de mayor edad ocupan la parte más austral del rango invernal de distribución. Las recapturas hechas en Abril y Mayo de Gaviotín Común provenientes de la isla Great Gull en el sur de Brasil y Argentina, prueban que algunas de estas aves son capaces de realizar un viaje de 8000 km en tan solo tres semanas o menos.
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