Influence of personal information, public information, and extra-pair paternity on breeding site fidelity in a songbird

Background/Question/Methods

I investigated the role of extra-pair paternity on use of public information and personal information for patch fidelity decisions.  It is unknown if songbirds use public information about the number of conspecific fledglings for patch fidelity decisions when extra-pair paternity is uncommon.  I tested if probability of patch fidelity was associated with (1) number of fledglings in adjacent territories (public information), and (2) number of fledglings raised with a social mate (personal information).  I used logistic regression to predict probability of patch fidelity of males and females based on the 2 uncorrelated predictor variables (Spearman’s rank correlation, S = 21895.28, n = 50, P = 0.723).  I monitored patch fidelity of 107 territories, counted the number of fledglings in each territory, and assessed parentage of 102 young from 36 nests for white-eyed vireos (Vireo griseus) from 2008–2010 in a 100 ha patch of woodland in central Texas, USA.  I excluded the social male as the father of 3 of the 102 young and did not exclude any of the social females as the mother with parentage analysis using 6 microsatellite loci.

Results/Conclusions

Number of fledglings in adjacent territories was not a good predictor of probability of patch fidelity for males (β₁ = 0.166, df = 35, P = 0.247, Nagelkerke’s R² = 0.054) or females (β₁ = 0.121, df = 17, P = 0.670, Nagelkerke’s R² = 0.016).  Number of fledglings raised with a social mate was also not a good predictor of patch fidelity for males (β₁ = –0.296, df = 43, P = 0.360, Nagelkerke’s R² = 0.029), whereas it was a good predictor for females (β₁ = 1.281, df = 21, P = 0.048, Nagelkerke’s R² = 0.409).  The dominant ecological concepts for explaining site fidelity in songbirds, personal reproductive success with a social mate and public information, did not predict probability of patch fidelity well for male white-eyed vireos.  Personal, but not public information was a good predictor of probability of patch fidelity for females.  My results suggest that use of public information may depend on frequency of extra-pair paternity.  Males may primarily use other information for patch fidelity decisions beyond reproductive success of conspecifics for patch fidelity decisions in some circumstances.  My results support the need to ensure high levels of nesting success for females to return and maintain populations in areas managed for breeding songbirds for conservation efforts to be successful.