Visualizações de Conteúdo : 100617
<<  Outubro 17  >>
 D  S  T  Q  Q  S  S 
  1  2  3  4  5  6  7
  8  91011121314
15161718192021
22232425262728
293031    
E-mail

     At the moment, the Laboratório de Ecologia e Conservação de Aves develops research on the following broad subjects:


         - Bird Ecology; Bird Conservation and Management; Avian Life History; Bird Migration; Geographic Distribution Modeling; Avian parasitism.

  

      Visit the "Publications" link to look at our published results, and the "Current Students" link to look at our ongoing study themes. Most of these publications and studies follow the two main projects of the lab briefly described below.

 

 ECOLOGY AND CONSERVATION OF CERRADO BIRDS

 

The good knowledge of basic population parameters is important to monitor the effects of environmental and climatic changes, estimate the viability of populations, evaluate habitat quality, and detect the most sensitive life stage of a species. However, to understand properly population parameters of a given species it is necessary to conduct well planned long term (> 10 years) studies. This project started in 2002, originally to study the “Demography and conservation of Cerrado birds”, will accumulate in 2013, 12 consecutive years of data collection in the same study site, including more than 5,000 nests monitored and more than 10,000 birds banded. Through these years it has been possible to collect data on population density, reproductive characteristics (e.g. breeding biology and reproductive success), climatic and birds’ food resources (i.e. arthropods and fruits), body condition, sex, and demographic parameters (e.g. adult survival rates, reproductive success, and productivity) of several Cerrado birds. With these data we have been testing several hypotheses, such as: 1) are Cerrado bird populations viable in local reserves; 2) do resources affect reproductive and survival parameters; 3) do demographic parameters vary in relation to body condition; and 4) do climatic changes affect Cerrado birds. The study is taken place at a 100 ha (1 km x 1 km) study plot with 23 km of narrow trails opened through the natural vegetation at Estação Ecológica de Águas Emendadas (ESECAE), Federal District (DF), central Brazil. Our field methodologies include bird banding (metal and color bands) and measurements (mass and size of body parts), estimates of resource biomass (arthropods and fruits), and search and monitoring of nests (visually, with i-buttons, or video cams). With the 12-year data set we are answering conservation wise questions such as analyzing the viability of populations, and predicting the responses of birds to climatic changes. Besides that, several theoretical questions have been tested with respect to the ecology and behavior of birds.

 
 

 

LIFE HISTORY PATTERNS AND KNOWLEDGE GAPS ABOUT BIRDS FROM THE NEW WORLD

     Life history strategies of Neotropical birds – small egg size, larger eggs, longer development periods – differ markedly from strategies of Nearctic birds. However, convincing explanations for these patterns have yet to be agreed upon. This happens especially because explanations are based on biological knowledge from the Northern Hemisphere, which has less than 25% of avian biodiversity. In contrast, the Neotropical region has more than 40% of the planet's avian biodiversity and lacks detailed studies connected to life history theory. Furthermore, traits of most species are unknown and we lack knowledge of broad geographical variation even of better-known traits. In addition to geographical patterns, related to local environmental conditions, life history strategies vary temporally as a result of climatic changes. Changes in breeding season and in clutch size due to temperature increase are well documented in the Northern hemisphere. However, little research has been done to evaluate temporal changes in life-history traits of Neotropical birds. In spite of the absence of long-term monitoring and broad geographical scale studies in traits of Neotropical species, the amount of information available in museums and in the literature is enormous, but usually ignored. With this project we aim to assemble and analyse data from scientific publications with basic breeding data and from major ornithological collections. We will visit the Alexander Library at The Edward Grey Institute of Field Ornithology, Oxford, England, and three museums: Museu de Zoologia da Universidade de São Paulo – MZUSP, São Paulo, Brazil; Western Foundation of Vertebrate Zoology – WFVZ, California, EUA, and; Natural History Museum – NHM, Tring, England. Using the reviewed data the goals of this project are: 1) review and quantify the breeding biology information (clutch size, linear egg measurements, incubation and nestling periods, and breeding season) of Tyranni (582 species pertaining to 5 families) across the New World; 2) map the breeding records, detect geographical gaps for each species, compare with existing distribution maps, and evaluate species resident/migratory patterns; 3) based on results from the previous item, sample three Brazilian sites lacking studies of nests and eggs and expand the collection of nest and eggs of the Marcelo Bagno Ornithological Collection at University of Brasília, Brazil (Coleção Ornitológica Marcelo Bagno da Universidade de Brasília); 4) test which ecological (nest type, migratory behaviour, biome) and environmental (latitude, elevation, seasonality) variables are related to geographical variation in life history traits, and; 5) test if life history traits vary temporally and if it is related to recent climatic changes. After all, we aim to frame all revised data in the current theoretical knowledge to help stimulate the development of Neotropical ornithology and life history theory.