Data from: Novel approaches for assessing acclimatization in birds reveal seasonal changes in peripheral heat exchange and thermoregulatory behaviors
Cite this dataset
Zuluaga, Juan; Danner, Raymond (2023). Data from: Novel approaches for assessing acclimatization in birds reveal seasonal changes in peripheral heat exchange and thermoregulatory behaviors [Dataset]. Dryad. https://doi.org/10.5061/dryad.n5tb2rc0w
Abstract
Using thermography and behavioral analyses, we found that heat exchange and thermoregulatory behaviors changed seasonally in chipping sparrows (Spizella passerina). Studies on seasonal acclimatization in birds have primarily involved metabolic measurements, few of which have investigated behaviors, and none have investigated changes in peripheral heat exchange. We captured chipping sparrows in the winter and summer of 2022 in Wilmington, North Carolina, and we collected thermal images of these birds at 15.0°, 27.5°, and 40.0°C. We found that heat dissipation through the bill and legs changed seasonally, but surprisingly both were higher in winter than in summer. We found that heat dissipating behaviors were more common in winter, whereas heat conserving behaviors were more common in summer, and that behaviors associated with resource costs (e.g., panting) or predation risk (e.g., bill tucking) showed the most distinct differences between seasons. Meanwhile, low-cost and low-risk postural adjustments (e.g., feather adjustments and tarsus exposure) did not vary as strongly between seasons but followed similar trends. The seasonal adjustments to behaviors suggest that non-acclimatized birds must use costly thermoregulatory behaviors more frequently than acclimatized birds. The use of thermography catalyzed the discovery of one completely novel behavior, and the first detection of a known behavior in a new species. Both novel behaviors aided in evaporative heat loss and occurred more commonly in winter, supporting the presence of seasonal acclimatization as evidenced by behavioral adjustments. These results provide novel insights to the process of acclimatization and suggest a role of behavioral adjustments in seasonal acclimatization.
README: Novel approaches for assessing acclimatization in birds reveal seasonal changes in peripheral heat exchange and thermoregulatory behaviors
The files titled "CHSP22.csv", "continuous.csv", "morph.csv", "tminmax", "CHSP.temps.csv", and "rh.data.csv" contain the data for "Novel approaches for
assessing acclimatization in birds reveal seasonal changes in peripheral heat exchange and thermoregulatory behaviors". These data were collected from
thermal images collected during experiments on Chipping Sparrows (Spizella passerina) during the winter and summer of 2022. In summary, the experiments
were conducted at 15°C (below the thermoneutral zone), 27.5°C (within the thermoneutral zone), and 40°C (above the thermoneutral zone) and involved the
use of a thermal imaging camera to measurethe surface temperatures of birds. The data come in the form of A) measurements of the surface temperature of
the bill, legs, and eye region, which are regions of interest for thermoregulation (CHSP22.csv), and B) instantaneously (CHSP22.csv) and continuously
(continuous.csv) sampled behavioral data of the birds during the experiment. Data on the morphology of each test subject are contained in "morph.csv".
Data on the ambient temperature and relative humidity inside the thermography chamber during each experiment are contained in "CHSP.temps.csv" and
"rh.data.csv", respectively. Local climate data during the study period are contained in "tminmax.csv".
Description of the Data and file structure
The file titled "CHSP.R" is an R script that contains the code for all statistical analyses and figures in the manuscript. The files titled "CHSP22.csv",
"continuous.csv", "morph.csv", "CHSP.temps.csv", and "rh.data.csv" contain the data for "Novel approaches for assessing acclimatization in birds reveal
seasonal changes in peripheral heat exchange and thermoregulatory behaviors". Values of NA in the data represent instances when the bird was facing away
from the camera during behavioral sampling or during measurements of surface temperature; these may also result for specific body parts (the bill or legs)
if they were tucked away for heat retention during the cold temperature treatment. Below is a description for each of the columns in the datasheets. The
units are listed at the end of the description where applicable.
Variables in 'CHSP22.csv':
bird: the individual bird's assigned ID number
temp: the ambient temperature during the experiment (degrees Celsius)
minute: the minute from which data were extracted during the second half of the temperature treatment
tall: 'tall' is an abbreviation of the binary variable for the presence of the tarsus exposure behavior
gape: binary variable for the presence of panting behavior
bill.tucked: binary variable for the presence of bill tucking behavior
legs.tucked: binary variable for the presence of leg tucking behavior
eye.reg.max: the maximum temperature of the eye region (degrees Celsius)
bill.mean: the average bill surface temperature (degrees Celsius)
leg.mean: the average leg surface temperature (degrees Celsius)
season: the season (winter or summer) during which the experiment was conducted
puff.level.1 binary variable for the presence of feather sleeking
puff.level.2 binary variable for the presence of neutral feather posture
puff.level.3 binary variable for the presence of full ptiloerection
Variables in 'continuous.csv':
bird: the individual bird's assigned ID number
season: the season (winter or summer) during which the experiment was conducted
birdid: the individual bird's assigned ID number combined with the season during which the experiment was conducted
wet: binary variable for the presence of tip wetting
Variables in 'morph.csv':
birdid: the individual bird's assigned ID number combined with the season during which the experiment was conducted
pre.weight: the weight of the individual before the experiment (grams)
post.weight: the weight of the individual after the experiment (grams)
tarsus: the length of the individual's tarsometatarsus (millimeters)
tarsus.width: the medial width of the individual's tarsometatarsus (millimeters)
tarsus.width2: the lateral width of the individual's tarsometatarsus (millimeters)
bill.length: the length of the individual's bill from the anterior edge of the nares to the tip (millimeters)
bill.width: the width of the individual's bill at the anterior edge of the nares (millimeters)
bill.depth: the depth of the individual's bill at the anterior edge of the nares (millimeters)
wing: the length of the individual's wing from wrist to tip (millimeters)
tail: the length of the individual's tail from base of the pygostyle to the tip of the tail (millimeters)
season: the season (winter or summer) during which the experiment was conducted
Variables in 'rh.data.csv':
bird: the individual bird's assigned ID number
birdid: the individual bird's assigned ID number combined with the season during which the experiment was conducted
season: the season (winter or summer) during which the experiment was conducted
rh15: the relative humidity inside the thermography chamber during each individual's 15 degree celsius treatment
rh27: the relative humidity inside the thermography chamber during each individual's 27.5 degree celsius treatment
rh40: the relative humidity inside the thermography chamber during each individual's 40 degree celsius treatment
Variables in 'tminmax.csv':
season: the season to which the measurement (tmin or tmax; see below) corresponds
tmin: mean minimum temperature by day for Wilmington, NC from 14 January to 26 February (degrees F)
tmax: mean maximum temperature by day for Wilmington, NC from 10 May to 14 July (degrees F)
Variables in 'CHSP.temps.csv':
trial: birdid (see below) combined with the trial temperature
Thermo: the ambient temperature during the experiment measured by a thermocouple (degrees Celsius)
season: the season (winter or summer) during which the experiment was conducted
temp: the ambient temperature during the experiment (degrees Celsius)
birdid: the individual bird's assigned ID number combined with the season during which the experiment was conducted
Sharing/access Information
Links to other publicly accessible locations of the data: NA
Was data derived from another source? No
If yes, list source(s):
Methods
These data were collected from thermal images collected during experiments on chipping sparrows (Spizella passerina) during the winter and summer of 2022. In summary, the experiments were conducted at 15°C (below the thermoneutral zone), 27.5°C (within the thermoneutral zone), and 40°C (above the thermoneutral zone) and involved the use of a thermal imaging camera to measure the surface temperatures of birds. We then collected measurements of the surface temperature of the bill, legs, and eye region, which are regions of interest for thermoregulation, and we instantaneously and continuously sampled behavioral data of the birds during the experiment. We then processed these data using mixed effects modeling.
Usage notes
R is necessary for the analysis, and we recommend using R Studio for convenience and ease of installation for the necessary R packages associated with the analysis.
Funding
University of North Carolina Wilmington
National Science Foundation