DOI: 10.5061/dryad.0k6djhb63
title: Data from: Anthropogenic nesting substrates increase parental fitness in a Neotropical songbird, the Pale-breasted Thrush (Turdus leucomelas)

description: The failure of breeding attempts is a major hindrance to bird
 reproduction, making nest site choice under strong selective pressure.
 Urbanization may offer lower risk of nest predation to certain bird
 species, but the impact of using anthropogenic structures as nesting sites
 on parental fitness is seldom studied. We studied the effect of
 anthropogenic substrates and brood parasitism by the Shiny Cowbird
 (Molothrus bonariensis) on the nest success of a Neotropical songbird, the
 Pale-breasted Thrush (Turdus leucomelas). We monitored 263 nesting
 attempts between 2017 and 2020 to estimate daily survival rate (DSR),
 which represents the probability of a given nest survive until the next
 day. DSR was modelled as a response variable in function of substrate type
 (plants as “natural” or human buildings as “artificial”) and brood
 parasitism as fixed factors, using as covariates year, a linear and a
 quadratic seasonal trends. Additionally, we tested the effect of these
 same explanatory variables on the number of fledglings per nest using a
 generalized linear mixed-effects model. Most nests (78.7%) were placed in
 artificial substrates and apparent nest success (i.e. the percentage of
 nesting attempts that produced at least one thrush fledgling) was higher
 in artificial (50.2%) than in natural substrates (37.5%). DSR was higher
 for nests in artificial than in natural substrates regardless of cowbird
 parasitism, whereas the number of fledglings per nest was higher both in
 artificial substrates and for nests without cowbird parasitism. We
 highlight that nesting in buildings significantly increases parental
 fitness in Pale-breasted Thrushes, which may favor their settlement in
 cities and potentially drive the evolution of this breeding behavior in
 urban birds.
description: # Data from: Anthropogenic nesting substrates increase parental fitness in
 a Neotropical songbird, the Pale-breasted Thrush (Turdus leucomelas)
 [https://doi.org/10.5061/dryad.0k6djhb63](https://doi.org/10.5061/dryad.0k6djhb63) Data on nesting attempts of the Pale-breasted Thrush (*Turdus leucomelas*) in southeast of Brazil. ## Description of the data and file structure These data were gathered by monitoring nests of the study species in two periurban areas of southeast of Brazil and report basical information about nest success and other variables, such as year, study site (São Carlos or Rio Claro municipalities), type of nesting substrate (human-buildings or trees) and the presence of brood parasitism by the Shiny Cowbird (*Molothrus bonariensis*). Other information include the day of the breeding season each nest was first and last checked, its age at discovering and its fate (successful, when at least one thrush chick survived until fledging or failed otherwise), as described below: year: study years, from 2017 to 2020 site: study sites, Rio Claro municipality (campus of the Universidade Estadual Paulista, 22º23’43”S, 47º32’46”W) or São Carlos municipality (campus of the Universidade Federal de São Carlos, 21º59’02’’S, 47º52’58’’W), both located at the central region of São Paulo State, southeast of Brazil substrate: the origin of nest substrate, artificial ("building") or natural ("tree") substratetype: the type of nest substrate structure nestcode: a numerical code (ID) of the nest clutchsize: number of thrush eggs per nest parasitism: the presence of parasitism by Shiny Cowbird (*Molothrus bonariensis*), coded 0 for absence and 1 for presence fledglings: number of thrush young that fledged per nest FirstFound: day of the breeding season that the nest was found (day 1 = the day of the first egg found in a given breeding season) AgeFound: estimated age of the nest when found from the day the first egg of that nest was laid (day 1) LastChecked: the day of the breeding season the nest was checked for the last time LastPresent: the day of the breeding season when the offspring was alive in the nest during nest checking AgeDay1: the number of days estimated between the day the first egg was laid in a given nest and the day 1 of the breeding season Fate: nest fate, coded as 1 at least one thrush chick survived until fledging or 0 otherwise NA: data not available