In a paper just published in The Auk (2018, 135: 299-313), Ferraz Lab graduate Alejandra P. Muñoz et al. use bird-banding data to investigate the latitudinal gradient in bird survival on two fronts. First, they quantify the effect of age on survival for forty species of Amazon forest passerines and find that adults of their tropical site have substantially higher survival probabilities than juveniles. Second, they compare their adult survival estimates with 342 survival estimates from 175 species from Peru to Alaska and find that survival does go down with increasing latitude. The latitudinal effect persists after accounting for effects of migration mode, phylogeny, and time of data collection. The authors conclude that the latitudinal gradient in survival is a fact, at least as seen among New World forest passerines.
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Gonçalo Ferraz
The III Porto Alegre Workshop on Hierarchical Modeling for Ecologists took place October 9-15, 2016. This was the third in a series of Porto Alegre Hierarchical Modeling Workshops, started in 2014. Each edition is focused on a particular modeling topic and the theme for 2016 is site-occupancy modeling with emphasis on the analysis of species distributions. The workshop opened with a one-day introduction to linear, generalized-linear and mixed models, describing their implementation in the Bayesian and likelihood frameworks. From day two on, we turned...
How many Vinaceous-breasted Parrots are there in western Santa Catarina? A group of six biologists from the Ferraz Lab and Unochapecó set out to answer this question in a recent field trip to the west of the Brazilian state of Santa Catarina, from December 12th to 16th, 2015. Ours is one deceivingly simple question with far-reaching implications...
Discursos sobre exploração de recursos naturais renováveis e conservação da biodiversidade
Dr. Guadanin gave an instructive overview of the conceptual and terminological problems at the crossroads between social anthropology and natural resource management. The talk emphasized renewable natural resource use by 'traditional' human groups, but it appears that efforts to generalize knowledge about such use stumble on the definition of 'traditional' and get trapped in a labyrinth of reifications. We discussed the need to clarify concepts, as well as the relative impacts of extractivism and land use change on biodiversity conservation. Renewable natural resource use by whoever does it will be more amenable to study once the people who do the use are sufficiently educated and empowered to formalize their economic activity. In the meantime, researchers may want to complement the social anthropology perspective with a microeconomic approach to solving the most pressing problems.
Is a bird in the hand worth two in the bush? A group of 30 bird banders set out to tackle this question in the IV Bird Banding and Molt Analysis Course (BBMA). The course took place from July 26 to August 1, at the Camp 41 of the Biological Dynamics of Forest Fragments Project (BDFFP), on upland primary forest of the central Brazilian Amazon...
The II Hierarchical Modeling Workshop took place at the Pousada Haras Cambará, in Porto Alegre, February 1-7, 2015. The workshop was co-taught by Marc Kéry (Swiss Ornithological Institute), Juan Manuel Morales (Universidad del Comahue, Argentina), Jérôme Guelát (University of Zurich), Murilo Guimarães (UFRGS) and Gonçalo Ferraz (UFRGS), with the assistance of Thiago Couto (UnB). The 22 attendants came from Argentina, Brasil, Chile, Colombia, Peru, and Uruguay...
The III BBMA course took place November 16-22 at the Pró-Mata research forest, 150 km from the city of Porto Alegre and on the southern end of the Brazilian Atlantic Forest. The initiative was sponsored by the Federal University of Rio Grande do Sul (UFRGS), with support from the National Audubon Society, the Louisiana Bird Observatory, the Costa Rica Bird Observatories, CORBIDI and ABECO.
Some initiatives work out ok, others exceed all expectations. The Bird-Banding and Molt Analysis course certainly went beyond everything the organizers had hoped for. About two years ago, Jared Wolfe and Gonçalo Ferraz started toying with the idea of organizing a bird-banding course at the BDFFP (Biological Dynamics of Forest Fragments Project, near Manaus, Brazil). The number of banders in the Manaus region...