Data from: Anthropogenic nesting substrates increase parental fitness in a Neotropical songbird, the Pale-breasted Thrush (Turdus leucomelas)
Data files
May 14, 2024 version files 26.23 KB
Abstract
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.
README: 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
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