Maria Alice S. Alves

Birds foraging for fruits and insects in shrubby restinga vegetation, southeastern Brazil

Abstract: Understanding how birds use vegetation to obtain food resources has implications for habitat conservation and management. Restinga is a poorly known and threatened tropical habitat, associated to the Atlantic forest, that could benefit from this kind of information to know which plants can be used and dispersed by birds that can help on the maintenance of this habitat. Frugivorous and insectivorous birds are important components of tropical ecosystems, such as restinga. To provide more information regarding the ecology of restinga, we studied the feeding behavior and spatial use of this vegetation by birds at Restinga de Jurubatiba National Park, southeastern Brazil. We found that feeding behavior was similar to that recorded for the same species in other vegetation types. In addition, spatial use of the restinga vegetation by the most abundant species did not overlap greatly, except for two insectivorous species that used different foraging maneuvers and two frugivorous birds that foraged in flocks. The two most abundant species were generalists in their diet and were capable of feeding at the ground level on sand substrate.

Endemic and threatened tetrapods in the restingas of the biodiversity corridors of Serra do Mar and of the Central da Mata Atlântica in eastern Brazil.

Biodiversity corridors comprise a mosaic of land uses connecting fragments of natural forest across a landscape. Two such corridors have been established along the eastern coast of Brazil: the Serra do Mar and the Central da Mata Atlântica corridors, along which most of the coastal plains are restinga areas. In this study, we analyze the present status of the endemic and endangered terrestrial vertebrates of both corridors. We sampled 10 restingas in both corridors, recording species of amphibians, reptiles, birds, and mammals. Some restingas harbor a relatively large number of endemic species,and two main regions of endemism can be identified along the restingas of both corridors: the coastal restingas from northern Espirito Santo State to southern Bahia State (between Linhares, ES, and Tarancoso, BA), and the coastal region between the restingas of Maricá and Jurubatiba, Rio de Janeiro State. Six species of terrestrial vertebrates considered threatened with extinction are found in the restingas of Serra do Mar and Central da Mata Atlântica biodiversity corridors (Liolaemus lutzae, Formicivora littoralis, Mimus gilvus, Schistochlamys melanopis, and Trinomys eliasi). The region located between the restinga of Maricá and that of Jurubatiba is of special relevance for the conservation of vertebrate species of the restingas of the corridors because a considerable number of threatened species of terrestrial vertebrates are found there. We strongly recommend efforts to develop checklists of threatened faunas for the States of Espirito Santo and Bahia.

Ácaros de penas e carrapatos (Acari) associados a Turdus albicollis Vieillot (Aves, Muscicapidae) em uma área de Mata Atlântica da Ilha Grande, Rio de Janeiro, Brasil

O parasitismo e um importante mecanismo que afeta populacoes e comunidades. O objetivo deste estudo foi investigar a fauna de ectoparasitos que habita o corpo do sabia-de-coleira, Turdus albicollis Vieillot, 1818 e avaliar se a massa corporal do hospedeiro e afetada por estes parasitos. Os individuos de T. albicollis foram mensalmente capturados na Ilha Grande, Rio de Janeiro, no periodo de julho de 1999 a junho de 2000, em uma area de Floresta Atlântica. As aves foram individualmente marcadas, pesadas e examinadas para registrar e quantificar a presenca de ectoparasitos. A abundância e a localizacao dos parasitos no corpo do hospedeiro foram registradas. Em 54 individuos de T. albicollis amostrados, foram encontrados duas especies de ectoparasitos. A prevalencia de acaros de penas, Pterodectes turdinus Berla, 1959, foi de 72,2% enquanto que a de carrapatos, Amblyomma longirostre Koch, 1844, foi de 27,8%. A abundância mensal de P. turdinus foi significativamente relacionada com os meses do ano, sendo maior nos meses com menor frequencia de chuva. Nao houve relacao estatisticamente significativa entre a massa corporal do hospedeiro (g) e a abundância total de acaros de penas e carrapatos.

A case of leucism in the burrowing owl Athene cunicularia (Aves: Strigiformes) with confirmation of species identity using cytogenetic analysis

Leucism is an inherited disorder, characterized by the lack of pigments in part or all of the body, normal coloration of the eyes and, in birds, in naked parts such as the bill and legs. This kind of disorder is sometimes erroneously designated as albinism or partial albinism. In this study, we present a case of leucism in a wild owl. The studied individual presented completely white plumage, light-yellow coloration of legs and bill and normal coloration of eyes. According to morphological features, this owl is a specimen of burrowing owl, Athene cunicularia (Molina, 1782). To confirm the species identity, we used cytogenetic analyses for karyotypic determination, comparing it to the previously described one in the literature. We also studied a captive female of A. cunicularia to complement the species karyotype, which was described in the literature based only on a single male. The karyotype of the leucistic owl individual was compatible with the previously published one for A. cunicularia, confirming the bird was a male specimen. Cytogenetic analysis of the captive female showed that the W sex chromosome is metacentric and comparable to the seventh pair in size. This is the first description of a case of leucism in A. cunicularia for South America. Long-term studies are needed in the Neotropical region to evaluate survival and breeding success in leucistic birds.

Patterns of Vertebrate Diversity and Protection in Brazil

Most conservation decisions take place at national or finer spatial scales. Providing useful information at such decision-making scales is essential for guiding the practice of conservation. Brazil is one of the world’s megadiverse countries, and consequently decisions about conservation in the country have a disproportionate impact on the survival of global biodiversity. For three groups of terrestrial vertebrates (birds, mammals, and amphibians), we examined geographic patterns of diversity and protection in Brazil, including that of endemic, small-ranged, and threatened species. To understand potential limitations of the data, we also explored how spatial bias in collection localities may influence the perceived patterns of diversity. The highest overall species richness is in the Amazon and Atlantic Forests, while the Atlantic Forest dominates in terms of country endemics and small-ranged species. Globally threatened species do not present a consistent pattern. Patterns for birds were similar to overall species richness, with higher concentrations of threatened species in the Atlantic Forest, while mammals show a more generalized pattern across the country and a high concentration in the Amazon. Few amphibians are listed as threatened, mostly in the Atlantic Forest. Data deficient mammals occur across the country, concentrating in the Amazon and southeast Atlantic Forest, and there are no data deficient birds in Brazil. In contrast, nearly a third of amphibians are data deficient, widespread across the country, but with a high concentration in the far southeast. Spatial biases in species locality data, however, possibly influence the perceived patterns of biodiversity. Regions with low sampling density need more biological studies, as do the many data deficient species. All biomes except the Amazon have less than 3% of their area under full protection. Reassuringly though, rates of protection do correlate with higher biodiversity, including higher levels of threatened and small-ranged species. Our results indicate a need for expanded formal protection in Brazil, especially in the Atlantic forest, and with an emphasis on fully protected areas.

Microhabitat Use and Orientation to Water Flow Direction by Tadpoles of the Leptodactylid Frog Thoropa miliaris in Southeastern Brazil

Frog larvae develop in a wide array of microhabitats including permanent and nonpermanent ponds, rivers, lakes, tank bromeliads, and other water reservoirs (Duellman and Trueb, 1994). A unique form of development and microhabitat specialization occurs in tadpoles of leptodactylid frogs of the genus Thoropa: tadpoles live in the film of water on rock surfaces at the wet borders of waterfalls in rain-forest areas, and in rocky fields of mountain ranges of southeastern Brazil (Bokermann, 1965; Caramaschi and Sazima 1984; Cocroft and Heyer, 1988). The tadpoles of this genus have an elongated, dorsoventrally compressed body, reduced fins, an expanded and flattened abdomen with an adherent ventral disk, and a long muscular tail, which, together with the labium, are used for movement and adhesion to the substrate (Bokermann, 1965; Wassersug and Heyer, 1983). Thoropa miliaris (Spix, 1824) occurs near freshwater bodies along the Atlantic rain forest of the states of Rio de Janeiro, Sao Paulo, Minas Gerais, and Espirito Santo in southeastern Brazil (Cocroft and Heyer, 1988) and also on rocky marine shores (Abe and Bicudo, 1991). Information available on microhabitat use by tadpoles of this species is restricted to general notes reporting the use of a very shallow film of current water on rock surfaces at the side of waterfalls with varying slopes, including vertical. These reports suggest that the tadpoles tend to remain with the head oriented against the water flow when adhered to the rock surface (Bokermann, 1965; Abe and Bicudo, 1991). However, there is no quantitative description of microhabitat use by this species. In this study, we analyze microhabitat use by T miliaris tadpoles to address the following questions. Do tadpoles orient randomly or selectively in relation to water flow? Do tadpoles tend to remain at the shallowest sites or use the available film of water indiscriminately? Do tadpoles occupy some slopes available on the waterfall surface more than others? Does water temperature where tadpoles occur differ from that of the main drainage of the waterfalls nearby?

Prediction of threatened tetrapods based on the species–area relationship in Atlantic Forest, Brazil

The species–area relationship was used to test the effects of habitat reduction on the proportion of tetrapod species that would be considered threatened with extinction, assuming the current estimate of 19% of remaining forest coverage in Rio de Janeiro State, Brazil. Here, species–area estimates from deforestation were compared with a Red List produced by experts. Analyses were performed with: (1) the total pool of species that occur in Rio de Janeiro State (159 amphibians, 115 reptiles, 635 birds and 157 mammals); (2) the pool of species endemic to the Atlantic forest (109 amphibians, 46 reptiles, 149 birds and 35 mammals). The sensitivity of the analyses to variations in the Z parameter of the species–area relationship was evaluated. In general, the species–area overestimated the total number of species threatened with extinction for all tetrapods, while the estimate of endemic mammals predicted to be extinct was close to the number of endemic species listed as threatened with extinction. Furthermore, changes in the Z-values did not affect those results. The species–area relationship accurately predicted the number of endemic birds assumed to be extinct since it used values of Z smaller than 0.25. The analyses with endemic species of reptiles and amphibians of Atlantic forest overestimated the number of species predicted to be extinct for both groups. In conclusion, at the considered scale, mammals and birds endemic to the Atlantic forest seem to be more affected by deforestation than reptiles and amphibians.

Two thrush species as dispersers of Miconia prasina (Sw.) DC. (Melastomataceae): an experimental approach

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% of the seeds ingested Our results suggest that both species could act as disperser agents of M. prasina.

Water depth selection during foraging and efficiency in prey capture by the egrets Casmerodius albus and Egretta thula (Aves, Ardeidae) in an urban lagoon in Rio de Janeiro State, Brazil

Este estudo teve o objetivo de avaliar a selecao de profundidade durante o forrageamento, a eficiencia na captura de presas e os itens alimentares capturados por Casmerodius albus (Linnaeus, 1758) e Egretta thula (Molina, 1782). O trabalho foi realizado em uma lagoa urbana, Lagoa Rodrigo de Freitas. Durante seis meses foram realizadas quatro transeccoes (duas de manha e duas a tarde). Quando as aves foram avistadas forrageando, foram registradas a profundidade da agua e o tipo de presa capturada. Nao foi encontrada relacao estatisticamente significativa entre a eficiencia de forrageamento para as duas especies de aves. Entretanto, as especies diferiram significativamente em relacao a profundidade da agua durante o forrageamento e tambem em relacao aos itens alimentares capturados. Casmerodius albus capturou principalmente peixes, enquanto E. thula capturou principalmente invertebrados. Os resultados sugerem que diferencas na profundidade da agua durante o forrageamento e nos itens alimentares capturados permitem um uso diferencial dos recursos alimentares disponiveis para C. albus e E. thula na Lagoa Rodrigo de Freitas.

Abundance, distribution and conservation of Rio Branco Antbird Cercomacra carbonaria and Hoary-throated Spinetail Synallaxis kollari

Summary Cercomacra carbonaria and Synallaxis kollari are passerine birds endemic to the gallery forests of Roraima state in northernmost Brazil and adjacent Guyana. The IUCN Red List of Threatened Species lists both as Vulnerable but they have been removed from Brazil’s list of threatened species because of data deficiency. They are poorly known, reflecting both Roraima state’s distance from Brazil’s main population centres and the inaccessibility of their habitat. In 2004 and 2005, we conducted bird surveys along the major rivers that provided previous sightings, and expanded records from only a handful to several dozens. We found C. carbonaria at 29% of the points surveyed, and estimated its local population density at approximately 80 individuals km 22 and total population size to exceed 15,000 individuals. The species has 723 km 2 of available habitat, 8% of which is inside conservation units. We found S. kollari at 44% of the points surveyed, and estimated its local population density as approximately 60 individuals km 22 , with an estimated total population size exceeding 5,000 individuals. It has 206 km 2 of available habitat, none of which is inside conservation units. We recommend that C. carbonaria be downlisted on the IUCN Red List to the Near Threatened category, and that S. kollari be listed as Endangered. Both species live in areas vulnerable to habitat loss. We also recommend that both species re-enter the Brazilian list of threatened species and highlight the importance of indigenous reserves to their conservation.