Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If you need an accessible version of this item please contact JSTOR User Support

Intersexual and Interspecific Differences in the Foraging Behavior of Rufous-Sided Towhees, Common Yellowthroats and Prairie Warblers in the Pine Barrens of Southeastern Massachusetts (Diferencias interespecíficas e intersexuales en la conducta de forrajeo de Pipilo erythrophthalmus, Geothlypis trichas y Dendroica discolor en pinares del sureste de Massachusetts)

David C. Morimoto and Fred E. Wasserman
Journal of Field Ornithology
Vol. 62, No. 4 (Autumn, 1991), pp. 436-449
Published by: Wiley on behalf of Association of Field Ornithologists
Stable URL: http://www.jstor.org/stable/20065822
Page Count: 14
  • Read Online (Free)
  • Cite this Item
If you need an accessible version of this item please contact JSTOR User Support
Intersexual and Interspecific Differences in the Foraging Behavior of Rufous-Sided Towhees, Common Yellowthroats and Prairie Warblers in the Pine Barrens of Southeastern Massachusetts (Diferencias interespecíficas e intersexuales en la conducta de forrajeo de Pipilo erythrophthalmus, Geothlypis trichas y Dendroica discolor en pinares del sureste de Massachusetts)
Preview not available

Abstract

Interspecific differences in the foraging behavior of the three most abundant breeding birds in the southeastern Massachusetts pine barrens were more pronounced than intersexual differences. Significant and relevant intersexual differences did exist, however, and help to explain how this community is organized. The foraging behavior of female Prairie Warblers (Dendroica discolor) was more similar to Common Yellowthroats (Geothlypis trichas) than to male Prairie Warblers. Of the three species, male and female Rufous-sided Towhees (Pipilo erythrophthalmus) showed the least amount of intersexual foraging differences. Male and female Common Yellowthroats foraged at different heights, but did not differ in the use of plant species or foraging maneuvers. The intersexual differences that existed are best explained by the hypothesis that sex-related reproductive activities constrain the behavior of individuals. Male Common Yellowthroats and Prairie Warblers often sang at heights above 3 m. The nests of these species were typically built in shrubs near the ground. Consequently, males of both species may have been foraging higher than females because of related male singing and female nesting activity. Male Rufous-sided Towhees may have been constrained morphologically to forage on the ground, because no intersexual differences in foraging height occurred despite the fact that males often sang well above the ground. /// Diferencias interespecíficas en la conducta de forrajeo de las tres especies residentes mas abundantes de los pinares del sureste de Massachusetts resultaron ser más marcadas que diferencias intersexuales. Sin embargo, se encontraron diferencias intersexuales significativas y relevantes que ayudan a explicar como esta organizada esta comunidad considerada pobre. La conducta de forrajeo de hembras de Dendroica discolor resultó ser más similar a la conducta exhibida por Geothlypis trichas, que a los machos de su propia especie. De las tres especies estudiadas, Pipilo erythrophthalmus, exhibio la menor diferencia intersexual de forrajeo. Los sexos de esta especie forrajearon a diferente altura, pero no difirieron en el uso de especies particulares de plantas o en las maniobras de forrajeo. Las diferencias intersexuales existentes pueden ser explicadas con la hipótesis que indica que las actividades reproductivas relacionadas a los sexos impone límites a la conducta de los individuos. Los machos de G. trichas y de D. discolor a menudo cantan a alturas superior a los 3 m. Los nidos de estas especies típicamente son construídos en arbustos pero cerca del suelo. Consecuentemente, los machos de ambas especies pueden haber estado forrajeando a mayor altura que las hembras debido a actividades relacionados con el canto y el anidamiento de estos, respectivamente. Los machos de P. erythrophthalmus pueden haber estado limitados morfológicamente a forrajear en los suelos. En estos no se encontró diferencia intersexual en la altura de forrajeo, aunque usualmente cantan a una altura considerable del suelo.

Page Thumbnails

  • Thumbnail: Page 
436
    436
  • Thumbnail: Page 
437
    437
  • Thumbnail: Page 
438
    438
  • Thumbnail: Page 
439
    439
  • Thumbnail: Page 
440
    440
  • Thumbnail: Page 
441
    441
  • Thumbnail: Page 
442
    442
  • Thumbnail: Page 
443
    443
  • Thumbnail: Page 
444
    444
  • Thumbnail: Page 
445
    445
  • Thumbnail: Page 
446
    446
  • Thumbnail: Page 
447
    447
  • Thumbnail: Page 
448
    448
  • Thumbnail: Page 
449
    449