New insights on the rarity of the vulnerable Cinereous Warbling-finch (Aves, Emberizidae) based on density, home range, and habitat selection / Esclarecimentos sobre a raridade do vulnerável capacetinho-do-oco-do-pau (Aves, Emberizidae) baseados em densidade populacional, área de vida e seleção de habitat

The Cinereous Warbling-finch Poospiza cinerea (Emberizidae) is a Neotropical grassland bird considered rare, with population declining due to habitat loss and classified as vulnerable. However, the species conspicuously remains in several degraded areas, suggesting that it may be favored by these environments. Studies which focus on this species were inexistent until 2012, making questionable any statement about its threaten status. Here we analyzed population density, home range, and habitat selection of two groups of P. cinerea at independent sites that differ in human impact levels. Density was estimated by counting and mapping birds. Kernel density and minimum convex polygon were used to estimate home ranges. Habitat selection was inferred from use and availability of every habitat identified within the home range boundaries. One group positively selected urban tree vegetation, despite the availability of natural habitats in its home range. Based on a review on the literature and our findings, we assume that it is unlikely that P. cinerea is rare owing to habitat degradation, as previously thought. Nevertheless, this species was always recorded around native Cerrado vegetation and thus habitat modification may still threaten this species at some level. It is suggested that this species might be a woodland edge species, but future studies are necessary to confirm this assumption.

O capacetinho-do-oco-do-pau Poospiza cinerea (Emberizidae) é um passeriforme neotropical de ambientes abertos, considerado raro e cuja população está em declínio devido à perda de habitat, sendo classificada como vulnerável. No entanto, a espécie tem sido observada com frequência em vários locais impactados, sugerindo que possa ser favorecida por esse tipo de ambiente. Estudos focados nessa espécie são escassos, o que nos leva a questionar qualquer afirmação sobre seu status de conservação. Nós analisamos a densidade populacional, área de vida e seleção de habitat de dois grupos de P. cinerea em dois locais independentes, que diferiam quanto ao grau de conservação. A densidade foi estimada por contagem e mapeamento das aves. Utilizamos Kernel density e Mínimo Polígono Convexo para estimar as áreas de vida. A seleção de habitat foi inferida a partir do uso e disponibilidade dos habitats nas áreas de vida. Um grupo selecionou positivamente árvores urbanas, apesar de ampla disponibilidade de vegetação natural na área de vida. Com base na revisão de literatura e também em nossas observações, consideramos improvável que a espécie seja rara devido à degradação de habitats naturais como anteriormente sugerido. Mesmo assim, a espécie sempre é observada em ambientes que contém vegetação nativa de Cerrado e, portanto, a degradação desse bioma pode ainda ser uma ameaça. É sugerido que Poospiza cinerea seja uma espécie de borda, e estudos futuros são necessários para confirmação dessa hipótese.

Diet and feeding behavior of the White-naped Jay, Cyanocorax cyanopogon (Wied, 1821) (Aves, Passeriformes, Corvidae) in a disturbed environment in central Brazil / Dieta e comportamento alimentar de Cyanocorax cyanopogon (Wied, 1821) (Aves, Passeriformes, Corvidae) em um ambiente antropizado na região centro-oeste do Brasil

The White-naped Jay Cyanocorax cyanopogon (Wied, 1821) is an omnivorous and opportunistic species, with a multifarious diet. In view of the scarcity of available data in the literature, the aim was to investigate and describe the bird's diet, location of food items, foraging tactics, actual feeding behavior and intraspecific interactions, as a means of defining the items consumed. The study was carried out in a Cerrado area in the Araguaia Campus of the Federal University of Mato Grosso – UFMT, in Pontal do Araguaia, Mato Grosso State, Brazil, from August to December, 2006, and from April to October, 2010. All the feeding events were recorded through 136 hours of animal focal sampling, whereby it was shown that these birds predominantly consume animal nutrients, replenished by vegetable items and human food-waste. Arthropods were predominant in the diet, with ants as the most abundant and frequent item. The fruits, flowers and seeds of eleven plant species were also consumed. Food-waste, representing about 1/10 of the total, was constantly consumed even when other food sources were available. Although active among the various strata, foraging is mainly on the ground. In the event of food-scarcity, the strategy employed is the hierarchical deployment of the members of various-sized groups, with the avoidance of direct competition. This versatility during all seasons, confirms total adaptation to the anthropic environment surrounded by native habitats that characterized the study site.

Cyanocorax cyanopogon (Wied, 1821) é uma espécie onívora e oportunista, que se alimenta de diferentes itens alimentares. Como há poucos relatos na literatura sobre sua alimentação, este estudo visou descrever os itens alimentares consumidos, o local de captura do alimento, as táticas de forrageamento, o comportamento alimentar e as interações intraespecíficas de C. cyanopogon. O estudo foi realizado em uma área de Cerrado do Campus Universitário do Araguaia, Universidade Federal de Mato Grosso, em Pontal do Araguaia/MT, de agosto a dezembro de 2006 e de abril a outubro de 2010. Por meio da amostragem animal focal foram registrados todos os eventos alimentares, num total de 136 h de observações. Os resultados demonstraram que C. cyanopogon consome predominantemente alimentos de origem animal, seguidos pelos de origem vegetal e por resíduos alimentares. Os artrópodes foram predominantes em sua dieta e as formigas foram os itens animais mais abundantes e frequentes. Frutos, flores e sementes de onze espécies de plantas também foram consumidos. Resíduos alimentares representaram cerca de um décimo dos itens consumidos, sendo ingeridos mesmo em períodos de disponibilidade de outras fontes alimentares. C. cyanopogon é forrageadora ativa e utiliza diferentes estratos para a captura do alimento, com maior utilização do solo. Forrageia sempre em grupos de tamanhos variados e apresenta um sistema hierárquico para o consumo de itens menos abundantes, sem haver competição direta pelo alimento. Por consumirem diferentes tipos de alimentos e em todas as estações do ano, conclui-se que C. cyanopogon está totalmente adaptada ao ambiente ocupado pelo ser humano, mas circundado por vegetação nativa, característica do local de estudo.

Effects of light intensity on circadian activity behaviour in the Indian weaverbird (Ploceus philippinus).

Circadian (locomotor activity/perching) behaviour of the weaverbird (Ploceus philippinus) under different light intensities was studied. Six groups of birds were subjected to 12L:12D (L = 1000 and 10 lux and D = 0.3 lux) for two weeks, and thereafter released into constant dim illumination (LLdim = 0.3 lux). After two weeks of LLdim, birds were given a 2 h light pulse of 1000 lux at circadian time (CT) 12, 17 and 20, and exposure of LLdim was continued for another two weeks and the activity pattern was monitored. As expected, all birds were entrained under 12L:12D showing dense-activity in the group that was placed under light phase of 1000 lux. Under LLdim birds exhibited circadian activity rhythms with periods longer or shorter than 24 h. Light pulse at CT 12 caused small delay shift in the activity phase, but a larger delay in phase shift occurred when the pulse was given at CT 17. A pulse at CT 20 caused small advanced phase shift. Thus, photoperiodic weaverbird appears to show circadian system regulated behaviour as seen by activity-rest pattern under programmed light cycles.

Daily and seasonal activity patterns in blackheaded munia.

To test the circadian clock characteristics, activity behaviour of male blackheaded munia was recorded. Two experiments were performed. In experiment 1A, activity of munia was recorded under long days, LD (14L: 10D); and short days, SD (10L: 14D). Locomotor activity of two groups of munia exposed to equinox (12L: 12D) daylength followed by transfer of one group each to continuous dimlight (DD) and continuous bright light (LL) was recorded in experiment 1B. Experiment 2 aimed to describe seasonal trend in daily pattern of activity/rest cycle under natural illumination conditions (NDL). Hourly activity during daytime was more under SD than under LD. Munia did not exhibit bimodality in daily activity pattern; activity during morning, M (2h) was more than evening, E. A free-running activity rhythm was recorded in munia under DD; the same was arrhythmic under LL. The seasonal pattern in daily activity profiles under NDL corresponds to the seasonal changes in daylength. Daylength regulates daily and seasonal activity patterns in blackheaded munia.

Light wavelength dependent circadian and seasonal responses in blackheaded bunting.

Animals in the wild are exposed to daily variations in sun light, viz. duration, intensity and spectrum. Photosensitive blackheaded buntings (Emberiza melanocephala) were exposed to photoperiods differing in the length of light period, wavelengths and intensity. The effects of such light changes were measured on locomotor activity rhythm as well as seasonal responses like development of migratory restlessness: Zugunruhe, body mass and gonadal growth. The results show that the buntings are differentially responsive to light wavelengths and intensities and are indicative of a phase-dependent action of light on the circadian photoperiodic system. These birds seem to use changes in the light variables of the solar environment to regulate their circadian and seasonal responses.

Are levels of digestive enzyme activity related to the natural diet in passerine birds?

Digestive capabilities, such as the rates nutrient hydrolysis and absorption, may affect energy intake and ultimately feeding behavior. In birds, a high diversity in gut biochemical capabilities seems to support the existence of a correlation between the morphology and physiology of the intestinal tract and chemical features of the natural diet. However, studies correlating the activity of digestive enzymes and the feeding habits at an evolutionary scale are scarce. We investigated the effect of dietary habits on the digestive physiological characteristics of eight species of passerine birds from Central Chile. The Order Passeriformes is a speciose group with a broad dietary spectrum that includes omnivorous, granivorous and insectivorous species. We measured the activity of three enzymes: maltase, sucrase and aminopeptidase-N. Using an autocorrelation analysis to remove the phylogenetic effect, we found that dietary habits had no effect on enzymatic activity. However, we found that granivorous and omnivorous species had higher levels of disaccharidase activities and insectivores had the lowest. The major difference in enzymatic activity found at the inter-specific level, compared to the reported lower magnitude of enzyme modulation owing to dietary acclimation, suggests that these differences to some extent have a genetic basis. However, the lack of a clear association between diet categories and gut physiology suggested us that dietary categorizations do not always reflect the chemical composition of the ingested food.

New records of the restinga antwren Formicivora littoralis Gonzaga and Pacheco (Aves, Thamnophilidae) in the state of Rio de Janeiro, Brazil: inland extended range and threats / Novos registros do Formigueiro-do-litoral, Formicivora littoralis Gonzaga e Pacheco (Aves: Thamnophilidae) no Estado do Rio de Janeiro, Brasil: expansão da distribuição continental e ameaças

The Restinga Antwren (Formicivora littoralis) has a narrow distribution range in southeastern Brazil, and it is a typical species of restinga habitat (sandy coastal plain vegetation). In this paper, we describe two new records for the species (22° 51' 45" S and 42° 14' 13" W; 22° 51' 14" S and 42° 11' 47" W) in the northern margin of the Araruama Lagoon, which represent a new inland limit for its distribution (11 km), besides assessing the current state of its habitat. We recorded supposed isolated subpopulations, most of them due the accelerated human-made fragmentation. The Massambaba Environmental Protection Area comprises the larger continuous extent of the suitable habitat for the Restinga Antwren, being essential to its long-term existence. However, the region lacks effective protected areas and, besides urgent practical measures, we recommend an accurate mapping and populational studies on this species.

Formicivora littoralis tem uma restrita faixa de distribuição no Sudeste do Brasil, sendo uma espécie típica de restinga. Descrevemos dois novos registros para a espécie (22° 51' 45" S e 42° 14' 13" W; 22° 51' 14" S e 42º 11' 47" W) na margem norte da Lagoa de Araruama, que representam um novo limite continental para sua distribuição (11 km), além de avaliar o atual estado de seu habitat. Registramos subpopulações supostamente isoladas, a maioria devido ao acelerado processo de fragmentação por intervenção antrópica. A Área de Proteção Ambiental de Massambaba compreende a maior extensão de habitat adequado para F. littoralis, essencial para sua existência a longo prazo. No entanto, a região carece de áreas de proteção efetiva. Recomendamos medidas práticas urgentes, além de um mapeamento acurado e estudos populacionais sobre essa espécie.

Two thrush species as dispersers of Miconia prasina (Sw.) DC. (Melastomataceae): an experimental approach / Duas espécies de Turdus como dispersoras de Miconia prasina (Melastomataceae): uma abordagem experimental

We carried out a seed germination experiment using two thrush species in captivity. We compared the number of germinated seeds and germination time of control seeds (manually removed from fruits) and ingested seeds of Miconia prasina by two bird species, Turdus albicollis and T. amaurochalinus, and also compared retention times of seeds by both thrush species. Control seeds germinated more frequently than those ingested for one species, T. albicollis. The germination time of ingested seeds by T. amaurochalinus was similar to the control seeds but seeds ingested by T. albicollis took longer to germinate than the controls. Both thrush species had a similar seed defecation pattern. The cumulative number of defecated seeds increased by 2 hours after fruit ingestion. At the end of the first 30 minutes both species had already defecated approximately 50 percent of the seeds ingested Our results suggest that both species could act as disperser agents of M. prasina.

Realizamos um experimento de germinação utilizando duas espécies de Turdus em cativeiro. Comparamos o número de sementes germinadas e o tempo de germinação entre sementes controle (manualmente removidas dos frutos) e ingeridas de Miconia prasina por duas espécies de aves, Turdus albicollis e T. amaurochalinus, e também comparamos o tempo de retenção das sementes pelas duas espécies de Turdus. Sementes controle germinaram com maior freqüência do que as ingeridas por uma das espécies, T. albicollis. O tempo de germinação das sementes ingeridas por T. amaurochalinus foi semelhante ao das sementes controle, mas as sementes ingeridas por T. albicollis demoraram mais para germinar do que as sementes controle. Ambas as espécies de Turdus tiveram um padrão similar de defecação das sementes. O número acumulado de sementes defecadas aumentou por 2 horas após a ingestão dos frutos. Ao final dos primeiros 30 minutos ambas espécies já haviam defecado aproximadamente 50 por cento das sementes ingeridas Nossos resultados sugerem que as duas espécies de aves podem atuar como agentes dispersores de sementes de M. prasina.

Potential role of frugivorous birds (Passeriformes) on seed dispersal of six plant species in a restinga habitat, southeastern Brazil

Restingas are considered stressful habitats associated with the Brazilian Atlantic forest, and their ecological interactions are poorly known. The goal of the present study was to determine the potential role of frugivorous birds as seed dispersers in a restinga habitat. Data were collected in Parque Nacional da Restinga de Jurubatiba, southeastern Brazil, where the main physiognomy (Open Clusia Formation) is characterized by the presence of patches of vegetation covering 20 to 48 % of the sandy soil and reaching a height of 5 m. Birds were captured with mist nets (12 x 2.5 m; 36 mm mesh; 1,680 net-hrs) and had their fecal and regurgitate samples inspected for seeds. Six plant species found in these bird samples were studied. The germination of seeds obtained from plants was compared to those from the birds. Both groups of seeds were set on Petri dishes at room temperature and washed when infected with fungi. In general, there was no effect on germination rate, and the effect on germination speed was negative. Germination of seeds from Pilosocereus arrabidae treated by the birds seemed to be influenced by storage of defecated seeds, while few Miconia cinnamomifolia seeds both from plants and from birds germinated. Ocotea notata presented a great variation in time to the onset of germination, perhaps an advantage against dissecation. Aechmea nudicaulis, Clusia hilariana and Erythroxylum subsessile probably take advantage of the arrival to favorable microhabitats, not by the gut effect on the seeds. All plant species studied are numerically important for the community and some of them are main actors in the succession of vegetation patches. Among the birds, Mimus gilvus is an important resident species, endemic to restingas in Brazil, while Turdus amaurochalinus is a visitor and may be important for plants that fructify during its passage by the study site. Although the effect of pulp removal was only tested for one species (Achmea nudicaulis)...

Las restingas se consideran hábitats estresantes asociados al bosque del Atlántico brasileño y sus ecológicas se conocen poco. El objetivo principal del presente trabajo fue determinar el papel potencial de las aves frugívoras como dispersores de plantas en un hábitat de restinga. La información se recolectó en el Parque Nacional da Restinga de Jurubatiba, Brasil. Las aves se capturaron con redes de niebla y sus muestras fecales y de regurgitación se inspeccionaron en busca de semillas. Estudiamos seis especies de plantas de estas muestras. En general, el efecto del paso por el sistema digestivo de las aves sobre el porcentaje de germinación fue nulo (y negativo en la velocidad de germinación). Todas las especies de plantas estudiadas son numéricamente importantes a la comunidad y algunas de ellas tienen papeles principales en la sucesión de parches de vegetación. Entre las aves, Mimus gilvus es una especie residente importante, endémica de tales hábitats en Brasil, mientras que Turdus amaurochalinus es una especie visitante y puede ser importante para las plantas que fructifican durante su paso por el sitio del estudio. El efecto general de los pájaros en la dispersión de semillas en la restinga es probablemente positivo.

Terrestrial passerines in an Atlantic forest remnant of Southern Brazil

Os microhábitats de quatro passeriformes de solo foram estudados no Parque Estadual Mata dos Godoy, um fragmento de floresta Atlântica no Sul do Brasil. Grallaria varia e Hylopezus nattereri apresentaram baixa abundância e ocorrência em apenas uma área do PG, enquanto Chamaeza campanisona e Corythopis delalandi foram registrados nas duas áreas. Os microhábitats de C. campanisona, G. varia e H. nattereri apresentaram muitas árvores de grande porte e um estrato inferior denso. O microhábitat de C. delalandi apresentou poucas árvores de grande porte.

Role of thyroxine and prolactin in the testicular status of spotted munia (Lonchura punctulata).

A long term investigation was made on the importance of thyroxine and prolactin in the reproduction of a tropical wild bird, spotted munia, Lonchura punctulata. Different doses of thyroxine i.m. (0.5, 1.0 and 2.0 microg; 0.56, 1.12 and 2.24 n mol Sodium salt, Sigma) per day/bird were administered in 0.1 ml of 0.9% alkaline NaCl per day per bird. Similarly various doses of prolactin (1.0, 2.0,. and 4.0 i.u.) were given per day/bird in 0.1 ml of 0.9% alkaline NaCl.Almost normal testicular cycle was observed in vehicle treated birds. All three doses of thyroxine suppressed the cycle almost completely indicating a gonado- inhibitory nature of the hormone. Testicular development in all three prolactin treated groups was also inhibited in peak breeding time which indicates the antigonadal nature of this hormone in the reproduction of this bird.

A twelve-month field study of the West African Thrush Turdus pelios (Passeriformes: Muscicapidae): Part 2: annual cycles

In Africa, birds inhabiting forested regions are less seasonal in their activities than those from open areas. In order to study annual cycles in forest regions of South western Nigeria, West African Thrushes (Turdus pelios ) were mist-netted and banded during the last two weeks of each month. The nest is a cup-shaped structure built out of grasses, herbs, weeds, roots and earth laid out in a clockwise manner. Only the nesting tree and feeding sites were defended during the breeding period. The clutch size was 2.69 ±0.20 eggs with a mean incubation period of 14.11 ±0.26 days. The mean nestling period was 15 ±1.00 days. The nestlings were fed on a variety of plant and animal matter, of which grass seeds and insects were predominant. Moult was found to be protracted with a population moult period of 194 days and a much shorter individual moult period. Moult and breeding periods were spread out: moult period dovetailed into the breeding period. The birds were found to gain weight during the period but they attained their maximum weight in August after the moult period. The lowest weight was recorded in February, during the peak of the dry season, when food availability was lower

El nido del tordo africano occidental es una estructura en forma de copa construida con pastos, hierbas, malezas, raíces y tierra, proyectado en el sentido de las manecillas del reloj. Solamente el árbol con el nido y los sitios de alimentación son defendidos durante la crianza. El tamaño de la nidada fue 2.69 ± 0.20 huevos con un periodo de incubación de 14.11 ± 0.26 días. El periodo promedio de cría fue de 15 ± 1.00 días. Los polluelos fueron alimentados con una variedad de material animal y vegetal, predominando las semillas de pasto y los insectos. La muda del plumaje alar es prolongada, con un período poblacional de muda de 194 días y un periodo individual mucho menor. La muda y crianza son tan prolongados que se empalman con el periodo de crianza. Las aves ganaron peso durante el periodo pero alcanzaron su peso máximo en agosto, después del periodo de muda. El peso más bajo fue el de febrero, lo que coincide con el pico de la estación seca, cuando los recursos alimenticios son escasos

A twelve-month field study of the West African Thrush Turdus pelios (Passeriformes: Muscicapidae). Part 1: food and feeding ecology

The feeding ecology of Turdus pelios was studied from field observations and gizzard contents. Quantitative data on feeding were obtained from repeated standard "fixed route "walks and observational points at seven sites from January to December 1998 on 5065ha at the Obafemi Awolowo University campus,Ile-Ife (7 º20 ’ N,4 º33 ’ E).Walks (each lasting about two hours)were started at various times of the day between 7.00 and 16.45 h.A total of 100 walks were made and binoculars were used to observe all feeding activities during 10 minutes at each site.Each feeding record included food type,method of feeding and reaction with con-specifics at feeding sites.Gizzards from mist-netted specimens were also studied.These birds fed most commonly twice a day between 06.00-9.30hr in the morning and between 17.00-18.30hr in the evening.Field observations showed that about 62%of the diet consisted of plant matter.The prey items were earthworms and terrestrial arthropods, of which orthopterans alone constituted 45%of the total.The prey size consumed by both sexes overlapped extensively:differences in prey size were significant only for spiders

Se examina la ecología alimenticia del ave Turdus pelios en Nigeria,África.Se observó que se alimenta frecuentemente dos veces al día entre 6:00 -9:30 am y entre las 17:00 -18:30 pm.Observaciones de campo mostraron que alrededor del 62%de la dieta consite en material vegetal. Las presas fueron lombices y artropodos terrestres,de los cuales los ortópteros constituyen el 45%del total.El tamaño de las presas consumidas por ambos sexos se traslapa ampliamente,y las diferencias fueron significativas solamente respecto al tamaño de las arañas (los machos consumieron más)