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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. rixosa foraged on the ground, A. leucocephala with P. sulphuratus were medium-height foragers, and T. melancholicus and M. similis form the third group for which prey attacks usually start from perches from the ground up to 3 m. With the exception of P. 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, P. 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.Este trabalho apresenta dados acerca do comportamento de forrageamento e substratos usados para a captura de presas por 28 espécies de tiranídeos (Tyrannidae) no Brasil. Para seis espécies: Arundinicola leucocephala Linnaeus, 1764, Fluvicola nengeta Linnaeus, 1766, Machetornis rixosa Vieillot, 1819, Myiozetetes similis Spix, 1825, Pitangus sulphuratus Linnaeus, 1766 e Tyrannus melancholicus Vieillot, 1819 -, também são apresentados dados sobre a altura do poleiro usado para caça, tempo de procura por presas, distância e ângulo de ataque. Com raras exceções, manobras do tipo "sally strike" foram as mais freqüentes, enquanto folhas vivas e o ar foram os substratos mais comumente usados para capturar presas. Para as seis espécies acima citadas três grupos de altura de forrageamento puderam ser discernidos: F. nengeta e M. rixosa forrageiam no chão, A. leucocephala e P. sulphuratus ocupam um estrato médio e T. melancholicus e M. similis formam um terceiro grupo e geralmente atacam suas presas a partir de poleiros situados a 3 m ou mais do chão. Com exceção de P. sulphuratus, que apresentou o tempo de procura mais longo, as outras cinco espécies não diferiram nesse aspecto. Três grupos foram também discernidos em relação à distância de ataque: F. nengeta e M. rixosa atacam presas próximas (< 2 m) a eles, A. leucocephala, P. sulphuratus e M. similis formam um grupo de média distância (3-4 m) e T. melancholicus apresentou as mais longas distâncias de ataque (até 12 m). As aves diferiram em alguns aspectos do ângulo de ataque que, juntamente com diferenças sutis em outros aspectos do comportamento de forrageamento podem levar a diferenças importantes na seleção de presas.

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