Extrapair mating behaviors in the field sparrow: nocturnal singing and extraterritorial forays

While there has been much research on the mating behaviors of birds, most attention has focused on elaborate and/or conspicuous mating displays, such as diurnal songs, ornaments, or mating dances. Much less attention has been devoted to investigating the role of more subtle behaviors, particularly nocturnal signing by diurnal birds and extra-territorial forays (movements off territory). My research explored the function of nocturnal singing and extra-territorial forays in the Field Sparrow (Spizella pusilla). I determined that nocturnal complex song serves to announce the presence of extra-pair males to females and that extra-territorial forays serve primarily in prospecting and soliciting extra-pair matings. While forays are common among both male and female Field Sparrows, a higher foraying rate did not result in greater extra-pair paternity (EPP). Rather, my data provide strong evidence that extra-pair matings are determined by current and previous relationships; females chose extra-pair sires that were current neighbors or neighbors or social mates during previous breeding seasons. Given female preference for extra-pair matings with neighbors, males who have information on the fertility status of neighboring females and coordinate their nocturnal vocalizations in relation to the fertility stage of neighboring females may be able to increase their EPP. Contrary to other studies, I did not find a relationship between the traits of males, females, or females’ social mates (age and tarsus length) and EPP. Thus, proximity to females, rather than male characteristics, appears to be key for a male’s success at acquiring extra-pair paternity. Finally, my findings are consistent with the hypothesis that female choice for extra-pair mates coupled with female foray behavior are driving patterns of extra-pair paternity and nocturnal singing behavior. By integrating research on nocturnal singing, extra-territorial foray behavior, and extra-pair paternity, my work has led to a more comprehensive understanding of extra-pair mating behavior in birds.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Natural Res & Env Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Celis Murillo, Antonio

Contributors dc:contributor

• Brawn, Jeffrey
• Ward, Michael P.
• Benson, Thomas J
• Suarez, Andrew V.

• Nocturnal Song
• Extraterritorial Forays
• Extra-pair mating behaviors
• Field Sparrow
• Nocturnal singing in diurnal birds
• Foray behavior
• Mating behaviors

Statement dc:rights

• Copyright 2015 Antonio Celis Murillo

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/88235

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/88235