Ecological opportunities and individual condition as predictors of extra-pair paternity in a south-temperate swallow (Tachycineta leucorrhoa)

FERRETTI, VALENTINA; MASSONI, VIVIANA; BULIT, FLORENCIA; LOVETTE, IRBY J.

JOURNAL OF FIELD ORNITHOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2018 vol. 89 p. 221 - 233

0273-8570

Ecological andphysiological factors such as breeding density, breeding synchrony, and adultbody condition can all affect extra-pair mating behavior, but the relativeimportance of these factors may vary among species. White-rumped Swallows (Tachycinetaleucorrhoa) nestingin Buenos Aires Province, Argentina, exhibit high rates of extra-pair paternity,with 77% of nests having extra-pair young. Our objective was to determine theextent to which extra-pair paternity in this species is explained by breedingsynchrony, breeding density, and adult body condition. Our study of a populationof White-rumped Swallows breeding in nest boxes was conducted during twoconsecutive breeding seasons (September ? early January 2006-2008). We foundthat neither breeding synchrony nor density of neighbors predicted levels ofextra-pair paternity in our study population. Leaner females were more likelyto engage in extra-pair behavior and fledged more nestlings, but did not differin structural size from females that did not engage in extra-pair behavior,suggesting that female mass is an important predictor of mating decisions and fitnessfor these aerial insectivores. Male body condition was not related to male extra-pairbehavior. The mass of female White-rumped Swallows may affect their flyingability such that, during their fertile period, they are exposed to morepotential extra-pair mates during longer foraging flights. Being lighter mayalso improve the ability of females to provision nestlings later in thebreeding cycle.<!-- /* Font Definitions */@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:"Arial Unicode MS";panose-1:2 11 6 4 2 2 2 2 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-134238209 -371195905 63 0 4129279 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-parent:"";margin:0in;margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:12.0pt;font-family:"Times New Roman";mso-fareast-font-family:"Arial Unicode MS";border:none;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-family:Cambria;mso-ascii-font-family:Cambria;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:"ＭＳ 明朝";mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:Cambria;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;}@page WordSection1{size:8.5in 11.0in;margin:1.0in 1.25in 1.0in 1.25in;mso-header-margin:.5in;mso-footer-margin:.5in;mso-paper-source:0;}div.WordSection1{page:WordSection1;}-->