DOI: 10.5061/dryad.kh18932js
title: Data from: Declining food availability alters vocal behavior of a nomadic finch

description: Social information (i.e., gathered from other individuals) can be an
 important information source for animal decision-making related to
 foraging and movement. For instance, social information in the form of
 acoustic cues can be used to locate food sources. The ability to
 accurately assess declines in food availability or quality in order to
 make movement decisions can also impact fitness. However, little is known
 about whether the acoustic cues produced by animals differ when food is in
 decline and could therefore be used as a source of information in this
 context. To test this hypothesis, we conducted a study on the effect of
 food availability on the vocal behavior of pine siskin (Spinus pinus).
 Pine siskins are gregarious, nomadic finches that feed on seeds that
 fluctuate irregularly and dramatically in abundance. We recorded and
 characterized the vocalizations of wild-caught birds in captivity under
 two experimental conditions: unlimited food and a 20% reduction in food
 availability. Birds called more frequently when food restricted and
 increased the production of two specific call types (Types B and C). For
 both of these call types, the minimum frequency was higher when birds were
 food restricted, and for C calls the median, peak dominant, and peak
 fundamental frequencies were also higher. We further tested whether
 changes in acoustic frequency were associated with circulating
 corticosterone levels, as is predicted by the hypothesis that circulating
 glucocorticoid levels mediate changes in acoustic frequency in response to
 food restriction, and found only limited evidence to support the
 hypothesis.
description: # Declining food availability alters vocal behavior of a nomadic finch
 Dataset DOI: [10.5061/dryad.kh18932js](10.5061/dryad.kh18932js) ##
 Description of the data and file structure This dataset includes activity,
 body mass, corticosterone, call count, and call frequency measurements
 collected from captive pine siskins experiencing unlimited food
 availability and restricted food availability, in a repeated measures
 experimental design. ### Files and variables #### File:
 Tir\_Watts\_TypeC\_subsample\_fundamental.csv **Description:** Data on the
 fundamental peak frequency of exemplar calls of type c ##### Variables *
 Freq_Peak: Peak fundamental frequency of the call * type: call type (‘cf’
 indicates call type c and fundamental) * Group: Experimental block (1, 2,
 3) * WhichFirst: Which treatment the bird experienced first (Control,
 Restriction) * Treatment: Which treatment the bird experienced for this
 sample (Control, Restriction) * Sex: M or F * Hour: The hour of sampling
 (1,2,3,4) * BirdID: Unique identifier for each bird #### File:
 Tir\_Watts2025\_Activity.csv **Description:** Activity data during each
 food manipulation trial ##### Variables * BirdID: Unique identifier for
 each bird * Sex: M or F * Group: Experimental block (1, 2, 3) *
 WhichFirst: Which treatment the bird experienced first (Control,
 Restriction) * Treatment: Which treatment the bird experienced for this
 sample (Control, Restriction) * Day: Day of experiment (integer) *
 Hour: The hour (1, 2, 3, 4) within each time category (M, A, N) *
 TimeCategory: Morning, Afternoon, Night * activity_total: The count of
 movements * activity_offset: The number of ten-minute bins included in the
 hourly total #### File: Tir\_Watts2025\_BodyMass.csv **Description:** Body
 mass measurements before and after each food manipulation ##### Variables
 * Date_Pre: Date that pre-trial mass was measured * Date_Post: Date that
 post-trial mass was measured * BirdID: Unique identifier for each bird *
 Group: Experimental block (1, 2, 3) * Sex: M or F * WhichFirst: Which
 treatment the bird experienced first (Control, Restriction) *
 Treatment: Which treatment the bird was experiencing during this data
 collection (Control, Restriction) * Mass_Pre: Body mass before the trial
 in grams * Mass_Post: Body mass after the trial in grams * Mass_Delta: The
 change in body mass (in grams) that occurred during the trial (Post minus
 Pre) #### Files: Tir\_Watts2025\_CallCounts\_TypeP.csv,
 Tir\_Watts2025\_CallCounts\_TypeB.csv,
 Tir\_Watts2025\_CallCounts\_TypeR.csv,
 Tir\_Watts2025\_CallCounts\_TypeC.csv,
 Tir\_Watts2025\_CallCounts\_TypeZ.csv,
 Tir\_Watts2025\_CallCounts\_TypeT.csv **Description:** These files have
 the the number of calls of produced for each of the six call types. Each
 call type is represented in a different file with the call type indicated
 in the file name. ##### Variables * BirdID: Unique identifier for each
 bird * Treatment: Which treatment the bird experienced for this sample
 (Control, Restriction) * TimeCategory: Morning, Afternoon, Night *
 Day: Day of experiment (integer) * Group: Experimental block (1, 2, 3) *
 WhichFirst: Which treatment the bird experienced first (Control,
 Restriction) * Sex: M or F * n: the total number of calls of the type
 produced by that individual in that time period #### File:
 Tir\_Watts2025\_CORT.csv **Description:** Pre- and post- trial plasma
 corticosterone data ##### Variables * SampleID: Unique identifier for each
 sample * Plate: Which plate the sample was located on * BirdID: Which
 plate the sample was located on * SampleDate: The date that the blood
 sample was taken in Day-Month format * Group: Experimental block (1, 2, 3)
 * Sex: M or F * WhichFirst: Which treatment the bird experienced first
 (Control, Restriction) * Treat: Which treatment the bird experienced for
 this sample (Control, Restriction) * PrePost: : Whether the sample is pre-
 or post- food manipulation * FinalConc: The plasma corticosterone
 concentration (ng/mL) #### File: Tir\&Watts2025\_TotalCalls.csv
 **Description:** Data on the total number of calls produced during food
 manipulation trails ##### Variables: * BirdID: Unique identifier for each
 bird * Sex: M or F * Group: Experimental block (1, 2, 3) * WhichFirst:
 Which treatment the bird experienced first (Control, Restriction) *
 Treatment: Which treatment the bird experienced for this sample (Control,
 Restriction) * Day: Day of experiment (integer) * TimeCategory: Morning,
 Afternoon, Night * n: the total number of calls produced by that
 individual in that time period #### File:
 Tir\&Watts2025\_TypeC\_subsample.csv **Description:** Data on the
 acoustic properties (i.e., frequencies) of exemplar calls of type c #####
 Variables * WhichFirst: Which treatment the bird experienced first
 (Control, Restriction) * Group: Experimental block (1, 2, 3) * Treatment:
 Which treatment the bird experienced for this sample (Control,
 Restriction) * BirdID: Unique identifier for each bird * Sex: M or F *
 Hour: The hour of sampling (1,2,3,4) * type: call type * Freq_5: Minimum
 frequency (5th percentile) of the call * Freq_95: Maximum frequency (95th
 percentile) of the call * Freq_Peak: Peak dominant frequency of the call *
 Freq_Center: Median frequency of the call #### File:
 Tir\&Watts2025\_TypeB\_subsample.csv **Description:** Data on the
 acoustic properties (i.e., frequencies) of exemplar calls of type b #####
 Variables * Group: Experimental block (1, 2, 3) * WhichFirst: Which
 treatment the bird experienced first (Control, Restriction) * Treatment:
 Which treatment the bird experienced for this sample (Control,
 Restriction) * BirdID: Unique identifier for each bird * Sex: M or F *
 Hour: The hour of sampling (1,2,3,4) * type: call type * Freq_5: Minimum
 frequency (5th percentile) of the call * Freq_95: Maximum frequency (95th
 percentile) of the call * Freq_Peak: Peak frequency of the call *
 Freq_Center: Median frequency of the call #### File:
 Tir\&Watts2025\_TypeC\_Syllables.csv **Description:** Data on the
 number of syllables type c call bout exemplars ##### Variables * Group:
 Experimental block (1, 2, 3) * Treatment: Which treatment the bird
 experienced for this sample (Control, Restriction) * BirdID: Unique
 identifier for each bird * Sex: M or F * WhichFirst: Which treatment the
 bird experienced first (Control, Restriction) * total_syll: count of
 syllables in call bout **Code/software** Files are in .csv format.