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Made available in DSpace on 2020-12-10T18:04:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-01 In this paper we present data on the foraging maneuvers and substrates used to capture preys by 28 species of tyrant flycatchers (Tyrannidae) in Brazil. For six species: Arundinicola leucocephala Linnaeus, 1764, Fluvicola nengeta Linnaeus, 1766, Machetornis rixosa Vieillot, 1819, Myiozetetes similis Spix, 1825, Pitangus sulphuratus Linnaeus, 1766, and Tyrannus melancholicus Vieillot, 1819 -, we go further to investigate perch height, search time, sally distance, and sally angle. With a few exceptions, sally strike was the most frequent foraging maneuver. Living foliage and air were the most frequent substrates used to capture preys. Among the six species Studied in detail we found three distinct groups of perch heights: F. nengeta and M. rixoso foraged on the ground, A. leucocephala with A sulphuratus were medium-height foragers, and T. melancholicus and H. similis form the third group for which prey attacks usually start from perches from the ground up to 3 m. With the exception of A sulphuratus, which had the longest search time, the other five species did not differ in this aspect of the foraging behavior. Three groups were also discernible in relation to sally distance: F. nengeta and M. rixosa usually attacked prey close (< 2 m) to them, A leucocephala, A sulphuratus and M. similis form a medium-distance (3-4 m) group, and T. melancholicus had the longest sally distances (up to 12 m). Birds differ in details of the sally angle that, together with other subtle differences in the foraging behavior, may render important differences in prey selection. Univ Estadual Paulista, Posgrad Ciencias Biol, Area Zool, BR-13506900 Rio Claro, SP, Brazil Univ Vale Rio Dos Sinos, Programa Posgrad Biol Ciencias Saude, BR-93022000 Rio Grande Do Sul, Brazil Univ Estadual Paulista, Posgrad Ciencias Biol, Area Zool, BR-13506900 Rio Claro, SP, Brazil

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2014-02-26T17:22:25Z No. of bitstreams: 0 Made available in DSpace on 2014-02-26T17:22:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:56:37Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T13:56:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-01-01 To investigate the movement of seeds transported by fruit-eating birds in an agricultural, fragmented landscape of the Atlantic forest of southeast Brazil, I asked which bird species are the main seed dispersers in such environment, and how they use the available habitats (small forest fragments, forest thickets, live fences, isolated trees, and active pastures) where they are most likely to drop the seeds they swallow the relative importance of fruit-eating birds as seed vectors was evaluated based on the number of fruit species eaten, the number of visits, and visitation rate to fruiting plants. Habitat use was accessed by recording the habitats where birds were seen or heard during walks conducted throughout the study area. Sixteen plant species were observed during 308.3 plant-hours. Forty-one bird species were observed eating fruits in a total of 830 visits to fruiting plants. Sayaca Tanagers (Thraupis sayaca) and Pale-breasted Thrushes (Turdus leucomelas) ate the greatest number of fruit species, were the most frequent plant visitors in terms of number and rate of visits, and had a broad range of habitat use. These two species and the Rusty-margined Guan (Penelope superciliaris), which is able to swallow large fruits with large seeds that smaller bird species cannot cat, likely have a great contribution to the movement of seeds throughout this highly degraded landscape. Univ Estadual Paulista UNESP, Dept Bot, Plant Phenol & Seed Dispersal Grp, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista UNESP, Dept Bot, Plant Phenol & Seed Dispersal Grp, BR-13506900 Rio Claro, SP, Brazil