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 Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Orientation and Microclimate of Horned Lark Nests: The Importance of Shade

C. Alex Hartman and Lewis W. Oring
The Condor
Vol. 105, No. 1 (Feb., 2003), pp. 158-163
Stable URL: http://www.jstor.org/stable/1370617
Page Count: 6
  • Read Online (Free)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Orientation and Microclimate of Horned Lark Nests: The Importance of Shade
Preview not available

Abstract

Across their range, Horned Larks (Eremophila alpestris) consistently construct their nests adjacent to and north of a conspicuous object such as a tuft of grass, shrub, or rock. We studied the relative importance of a northern nest orientation to nest microclimate in Horned Larks breeding in northeastern California. Nests showed a significant northern bias in orientation angle and were 49% shaded in the early afternoon, the hottest part of the day. Artificial nests of eastern, western, and southern orientations exhibited little to no shade during this time. A northern nest orientation also allowed nests to face prevailing winds during the day and avoid them in the evening. The Horned Larks' preference for a northern nest orientation offers multiple advantages for regulation of nest microclimate. /// De forma consistente a lo largo de su rango de distribución, Eremophila alpestris construye sus nidos adyacentes a y al norte de objetos conspicuos, como parches de pasto, arbustos o rocas. Estudiamos la importancia relativa de la orientación de los nidos hacia el norte para el microclima de éstos en individuos de E. alpestris que se reproducen en el noreste de California. El ángulo de orientación de los nidos presentó un sesgo significativo hacia el norte y éstos tuvieron un 49% de sombra durante las primeras horas de la tarde, el período más caliente del día. Nidos artificiales con orientación hacia el este, oeste y sur exhibieron poca o ninguna sombra durante esa parte del día. La orientación hacia el norte también permitió a los nidos orientarse hacia la dirección predominante del viento durante el día y evitar los vientos durante el atardecer. La preferencia de E. alpestris por la orientación de los nidos hacia el norte ofrece múltiples ventajas para la regulación del microclima del nido.

Page Thumbnails

  • Thumbnail: Page 
158
    158
  • Thumbnail: Page 
159
    159
  • Thumbnail: Page 
160
    160
  • Thumbnail: Page 
161
    161
  • Thumbnail: Page 
162
    162
  • Thumbnail: Page 
163
    163