DOI: 10.5061/dryad.3xsj3txkn
title: Data from: The scope and adaptive value of modulating aggression across breeding stages: Case study in a competitive female songbird

description: In seasonally breeding animals, costs and benefits of territorial
 aggression should vary over time; however, little work thus far has
 directly examined the scope and adaptive value of individual-level
 plasticity in aggression across breeding stages. We explore these issues
 using the tree swallow (Tachycineta bicolor), a bird species in which
 females compete for limited nesting sites before producing a single brood.
 We measured the aggressiveness of nearly 100 females within three
 different stages: (1) shortly after territory-establishment, (2) during
 early incubation, and (3) while caring for young chicks. We used k-means
 clustering to categorize females into four distinct plasticity ‘types’
 based on the timing, direction, and magnitude of their changes in
 aggression between stages. We then tested whether plasticity type and
 stage-specific aggression vary with key performance metrics. Two of the
 four plasticity types became less aggressive across consecutive breeding
 stages, consistent with population-level patterns, though these plasticity
 types largely did not differ from one another in survival or reproductive
 success. A third type was characterized by high levels of among-stage
 plasticity; these females, had significantly lower body mass while
 parenting, tended to hatch fewer eggs, and had the lowest observed
 overwinter survival rates. A final type exhibited limited plasticity, with
 moderate to low levels of aggression in all stages; this low plasticity -
 low aggression phenotype was not associated with any negative effects to
 performance. These results reveal substantial among-individual variation
 in behavioral plasticity, which may reflect diverse solutions to
 trade-offs between current reproduction and future survival.
description: Collection and processing of the data described in detail in the
 manuscript "The scope and adaptive value of modulating aggression
 across breeding stages: case study in a competitive female
 songbird". 
description: All analyses were conducted in R.
description: # Data from: The scope and adaptive value of modulating aggression across
 breeding stages: Case study in a competitive female songbird Paper: Scope
 and adaptive value of modulating aggression over breeding stages in a
 competitive female bird Authors: Elizabeth M George, Abigail M Weber,
 Kimberly A Rosvall Description: This README file describes the data
 accompanying the above publication. Each line of data refers to data
 collected from one female tree swallow during one particular year. Below
 are descriptions of the contents of each column: * Year= calendar year.
 2018 corresponds to Y1 in text, 2020 corresponds to Y2 *
 F_ID= female ID (unique 9-digit federal band #) * Age_class
 = y1 = one year old (brown plumage) females, y2+ are females 2y old or
 older (blue-green plumage) * Age= age in years 
 * How_aged= whether female’s age is exact (‘known’) or an estimated
 minimum, based on their plumage when originally banded (see next 3
 columns) * year_banded= year when female was first banded.
 Used with ‘Age_class_whenbanded’ to estimate age *
 Age_class_whenbanded = whether females were nestlings (y0), one-year old
 brown plumaged (y1) or 2y or older (blue-green plumage; y2+) when first
 banded. Used for estimating age * banded_in_prioryear= yes
 or no (Y/N), whether a female had previously been captured/banded at one
 of our study sites. Indicates whether a female was new to our study
 population at the time of the aggression assays *
 TE_STI_score, Inc_STI_score, C_STI_score: result of 5 minute aggression
 assay (STI), defined as # of 5 sec time bins that contained any aggressive
 behavior (range= 0-60) * TE = aggression measured during Territory
 Establishment (TerrEst) stage, Inc= during incubation, C= during
 chick-rearing * F_mass: female body mass, measured in grams * ‘NA’s
 indicates that we did not measure body mass during Inc or C for that
 female. * F_mass_stage: breeding stage in which body mass was measured
 (either Inc for incubation or C for chicks) breeding stage (Inc or C). All
 Y2 measurements occurred during C, and almost all Y1 measurements occurred
 during Inc. *  F_return_nextyr: whether a female was captured at our study
 sites in the following year’s breeding season (2019 for Y1, 2021 for Y2).
 Used as a proxy for overwinter survival. Y= ‘yes, female returned’, N=
 ‘no, female was not seen again’ * laydate_first= the date of a
 female's first clutch initiation, used in analyses of 'first egg
 day' as a response variable * laydate_brood= the date of a
 female's clutch initiation for the nest whose chicks' mass and
 survival were analyzed. this differed from laydate_first only for the
 select cases in which a female's first clutch failed and she
 successfully relaid and raised chicks * relaid_nest = whether or not the
 reproductive data from a female (n_c_hatched, avg_D12_c_mass, etc.) came
 from a female’s second attempt at a nest, because her first nest failed
 for some reason. Y= yes, was a relaid nest, N= not a relaid nest. Used to
 filter data prior to analyses of reproductive performance *   n_e_laid=
 number of eggs laid by a female (specific to one reproductive effort, not
 counting relaid nests). Represents clutch size except in the cases when
 clutch reduction occurred (next column) * clutch_reduct= ‘clutch reduction
 amount’. how many eggs were artificially removed from a nest after laying
 but before hatching * n_e_couldhatch= ‘number of eggs that could hatch’.
 The difference between n_e_laid and clutch_reduct. Used to measure
 hatching success * hatchdate= calendar date on which the majority of a
 brood hatched * n_c_euth_d6= ‘the number of chicks euthanized on day 6
 post-hatch’. A count of the number of chicks terminally collected for
 another study- occurred on day 6 post-hatch * n_c_d12- ‘number of chicks
 alive in nest on day 12 post-hatch’ * ‘NA’ indicates that the number of
 chicks alive in the nest at that time could not be evaluated *
 avg_D12_c_mass= brood-average chick mass (in grams) on day 12 post-hatch *
 ‘NA’ indicates that 0 chicks were alive in the nest on day 12 (i.e., the
 nest ‘failed’ due to predation, abandonment, etc.), and thus body mass
 could not be measured * n_c_euthd12= ‘number of chicks euthanized on day
 12 post-hatch’. A count of the number of chicks terminally collected for
 another study- occurred after day 12 mass measurements * n_c_alive_pd12=
 ‘number of chicks alive post-day 12’, calculated as the difference between
 n_c_d12 and n_c_euthd12 * ‘NA’ indicates that 0 chicks were alive in the
 nest on day 12 (i.e., the nest ‘failed’ due to predation, abandonment,
 etc.), so this measure is irrelevant * brood_reduction= ‘total artificial
 brood reduction’, sum of n_c_euth_d6 and n_c_euthd12 * c_recruit= ‘chick
 recruitment’. Binary variable: were any fledged chicks from this brood
 captured found in the breeding population the following year? (Y=
 yes/N=no) * ‘NA’ indicates that 0 chicks were alive in the nest on day 12
 (i.e., the nest ‘failed’ due to predation, abandonment, etc.), so
 fledgling recruitment could not be measured * Year_ID= concatenation of
 Year and Female ID, giving unique ID per female per breeding season *
 TE_Inc_scorediff= ‘TE, Inc STI score difference’. Inc STI score minus TE
 STI score * Inc_C_scorediff= = ‘Inc, C STI score difference’. C STI score
 minus Inc STI score * fmass_ebr= ‘female mass-relevant experimental brood
 reduction’. A binary variable indicating whether a clutch or brood
 reduction occurred prior to a female’s body mass measurement (Y=yes, N=no)
 * fsurv_ebr= ‘female survival- relevant experimental brood reduction’. A
 binary variable indicating whether a clutch or brood reduction occurred at
 any stage, which could have affected a female’s survival to the next year
 (Y=yes, N=no) * hatch_ebr = ‘hatch-relevant experimental brood reduction’.
 A binary variable indicating whether a clutch reduction occurred prior to
 hatching, which could have affected hatcing success (Y=yes, N=no) *
 d12m_ebr= ‘day 12 chick mass-relevant experimental brood reduction’ A
 binary variable indicating whether a clutch or brood reduction occurred
 prior to chick mass measurements on day 12 post-hatching (Y=yes, N=no) *
 csurv_ebr= ‘chick survival/recruitment-relevant experimental brood
 reduction’. A binary variable indicating whether a clutch or brood
 reduction occurred at any stage, which could influence whether chicks were
 recruited into the study population in the following year (Y=yes, N=no) *
 F_return_nextyr_bi = ‘female return next year binary’, converts the
 F_return_nextyr into 0s and 1s, for statistical analyses (N=0, Y=1). R
 script for data analyes and figures is also provided, to be run in
 sequential order using this data set.