Data for: Body condition of phocid seals during a period of rapid environmental change in the Bering Sea and Aleutian Islands, Alaska

Data and R code to accompany the paper, Body condition of phocid seals during a period of rapid environmental change in the Bering Sea and Aleutian Islands, Alaska. Deep Sea Research Part II: Topical Studies in Oceanography, 2020, 104904, ISSN 0967-0645, https://doi.org/10.1016/j.dsr2.2020.104904.

We used multiple linear regression to model body condition (mass/length) as a function of species, age class, sex and year for ribbon and spotted seals in the Bering Sea, and harbor seals in the Aleutian Islands, from 2007 to 2018, for evidence of recent trends that might reflect trophic or bottom-up changes in the ecosystem.

The file "ultrasound morph data_2018Dysonall_20072009.csv" is a spreadsheet text file with the following data fields:
speno: A unique specimen number for each seal
species: Eb = Erignathus barbatus, bearded seal; Hf = Histriophoca fasciata, ribbon seal; Pl = Phoca largha, spotted seal; Pv = Phoca vitulina, harbor seal
year: Calendar year of the sampling event
capture_dt: Date, hour, and minute of sampling, in UTC
project: Project name identifier
sex: M = male; F = female
age_class_lku: ADT = adult; SUB = subadult; YOY = young of the year; PUP = maternally dependent pup
blubber_depth_dor_hip_cm_a: Ultrasonic measurement of blubber depth, dorsal at hip, in centimeters
blubber_depth_r_lat_hip_cm_a: Ultrasonic measurement of blubber depth, lateral at hip, in centimeters
blubber_depth_dor_ax_cm_a: Ultrasonic measurement of blubber depth, dorsal at axilla, in centimeters
blubber_depth_r_lat_ax_cm_a: Ultrasonic measurement of blubber depth, lateral at axilla, in centimeters
std_length_cm: Straight-line length, prone, nose to tip of tail, in centimeters
curv_length_cm: Curvilinear length along body surface, prone, nose to tip of tail, in centimeters
ax_girth_cm: Axillary girth, in centimeters
max_girth_cm: Maximum girthAxillary girth, in centimeters
hip_girth_cm: Girth at hipsAxillary girth, in centimeters
final_mass_kg: Body mass, in kilograms

The file "bodycondition_analysis.R" contains the R statistical language code for the analysis reported in the paper.