DOI: 10.5061/dryad.v15dv4240
title: Nutritional condition of mule deer in western Wyoming, USA

description: Deterioration in nutritional condition with aging could reduce
 reproductive success but coincides with declines in residual reproductive
 potential, thus invoking opposing expectations for late-life reproduction.
 Yet, the mechanisms regulating energy accrual and allocation to
 reproduction and survival throughout the lifetime of long-lived,
 iteroparous animals have remained elusive owing to variation in energetic
 costs across their extended reproductive cycle (from conception to
 juvenile independence). Using 10 years of repeated measures of both
 nutrition (i.e., body fat and food availability) and reproductive
 allocation across the reproductive cycle of 232 free-ranging, adult,
 female mule deer, we revealed that nutrition is a critical piece in
 understanding patterns of reproductive senescence and terminal investment.
 From conception to weaning, age-related patterns of reproduction were
 influenced by both body fat and environmental conditions. Reproductive
 senescence was clear across the entire reproductive cycle, although
 allocation to offspring was partly mediated by nutrition. Terminal
 investment, however, was most evident towards the end of the annual
 reproductive cycle and unveiled only when considering nutritional
 condition and food availability; during years with poor resource
 availability, older mothers raised larger juveniles (6-month old
 juveniles). Our work evokes nutrition as a lurking variable in end-of-life
 reproductive tactics for long-lived animals, while demonstrating the
 necessity of accounting for energy when considering patterns of
 reproductive senescence and terminal investment in wild animals.
description: We used data on age, nutrition, and reproductive investment of
 female mule deer from December 2013 to December 2022. We captured 70
 adult, female mule deer using helicopter net gunning in December 2013.
 Each spring and autumn following that initial capture event, we recaptured
 all surviving individuals and captured new individuals to maintain a
 sample size of 70 animals. At the initial capture event for an animal, we
 extracted one insiform canine to assess age of individuals using cementum
 annuli and assigned a unique animal identifier (e.g., “001”). At every
 capture event, we measured body mass, determined nutritional condition,
 and fit all animals with a GPS radio-collar programmed to take satellite
 fixes every five hours from December 2013 to March 2015, every two hours
 from April 2015 to March 2018 and every one hour from April 2018 to
 December 2022. Nutritional condition of individuals was determined using
 developed protocols for mule deer which include measuring subcutaneous
 rump fat via ultrasonography and body palpation to estimate a body
 condition score. We calculated percent ingesta-free body fat (hereafter,
 body fat) of all animals. Each spring, we assessed pregnancy status and
 fetal number using ultrasonography, and fit all pregnant animals with
 Vaginal Implant Transmitters. Beginning in 2015, we
 monitored all pregnant females each day in spring to identify birth
 events. Following a VIT expulsion alert, or using movement data to
 identify parturition events, we located the adult females and assessed if
 a birth event had occurred. For animals that had given birth, we searched
 the surrounding area for newborn deer. Upon location, we carefully
 restrained, collected data on sex, newborn mass (kg), and morphometrics
 and placed an expandable collar on the animal (ATS VHF 2015; ATS neolink
 2016 – 2017; Vectronic Aerospace GPS 2018 – 2022). All newborn animals
 were assigned a unique animal identifier (e.g., “F001”). Most newborn deer
 (&gt; 90%) were captured either the day they were born or the day
 following their birth. Following capture, we monitored survival of all
 deer captured as newborns throughout the summer. Upon identifying a
 mortality event, we investigated the mortality as soon as possible to
 determine the cause of death. Beginning in 2019, we
 recaptured all surviving juveniles (i.e., offspring that were 6 months of
 age) the first December following their birth following the same general
 protocol of capture and handling adult animals. Following capture of
 juvenile deer in December, we measured juvenile mass (kg) and determined
 body fat of all juvenile animals. We did not extract incisiform canines of
 any juvenile deer because we had known information on birth date and age.
 Adult animals had the following metrics of reproductive effort: pregnancy
 status (binary, 0 or 1), fetal number (categorical, 1 - 3), spring body
 fat (%), mass of newborn (kg), mass of juvenile (kg), survival of
 offspring, and autumn body fat (%). <em>Spatial
 Data</em> Mule deer in this population migrate
 each spring and autumn between their seasonal ranges. We delineated the
 start and end date of both spring and autumn migrations of each individual
 using net squared displacement in Migration Mapper.  Mule deer in this
 population have very distinct summer and winter ranges, and net squared
 displacement is an effective tool at delineating migratory events. Next,
 we created seasonal home ranges for each individual deer using dynamic
 Brownian Bridge (dBBs) movement models with 95% contours for both winter
 and summer ranges. We created winter ranges for each individual using GPS
 data from 1 December to 28 February of each year. If animals were still
 completing their autumn migration after 1 December, we removed all GPS
 locations before their first day following the end of autumn migration. If
 animals began their spring migration before 28 February, we removed all
 GPS locations starting on the day they began their spring migration. We
 created summer home ranges from 1 June to 30 September. If animals had not
 completed their spring migration by 1 June, we removed all GPS locations
 until the day after they had completed their spring migration. If animals
 began their autumn migration before 30 September, we removed all GPS
 locations beginning on the day they began their autumn
 migration. We used remotely sensed data of snow depth
 available through the Snow Data Assimilation System (SNODAS). We
 calculated the average snow depth in winter (from December 1 – Feb 28) and
 extracted the average snow depth during each winter from each home range
 of individual mule deer using the terra package in program R, version
 4.2.2.   We estimated per capita precipitation on each
 summer range, which influences fat accumulation of deer over summer. We
 used remotely sensed data of precipitation with daily estimates of
 precipitation available through DAYMET. We calculated cumulative
 precipitation by summing values of each pixel from 1 June to 30 September.
 We then calculated the average cumulative precipitation on summer range
 for each individual deer. We divided the cumulative precipitation value by
 population estimate.
description: # Terminal Investment and Senescence Dataset
 [https://doi.org/10.5061/dryad.v15dv4240](https://doi.org/10.5061/dryad.v15dv4240) Data collected from adult female mule deer and juvenile mule deer from 2013 to 2022. ## Description of the data and file structure There are two data files that include information on both adult and juvenile. The first file (wrmd_fitness_fawn.dat.sub_submission) includes information about adult female animals, and relevant information on the size of the fawn she gave birth to. It includes the following columns: DecWeight - mass of adult (in kg) in December DecFat - fat of adult (% ingesta free body fat) in December DecLeanMass - ingesta free fat free body mass of adult in December (in kg) Age - age of adult animal (years) MarchWeight - mass of adult (in kg) in March MarchFat - fat of adult (% ingesta free body fat) in March MarchLeanMass - ingesta free fat free body mass of adult in March (in kg) Pregnancy - pregnancy status of adult in March, 1 = pregnant, 0 = not pregnant FetalNum - number of fetuses an adult animal was pregnant with in March EndDate - final date of monitoring for the Adult animal CoD - cause of death for the adult animal Censor - indicates if the mortality date should be censored from a survival analyses Censor_Reason - reason if the animal is censored from survival analyses fallfawns - the number of animals an adult animal recruited in the autumn lactation score - A quantitive score that indicates how full the udder was during December captures change.fat - the change in fat between March and December for an adult animal in a given year. CapDate - the date a fawn was captured in the spring. FawnAge - the age of the fawn at capture (in days) FawnMAss - the weight of the fawn at capture (in kg) age2 - the squared age of the adult animal. j.bday - the julian birthdate of the fawn. uid - the unique indentifier of the adult animal The second dataset (wrmd_fitness_juvenilemass_submission) includes information about adult female animals, and relevant information on the size of the fawn she gave birth to and how large the fawn was at 5-6 months of age. It includes the following columns: AutMass - mass of adult (in kg) in December AutFat - fat of adult (% ingesta free body fat) in December AutLeanMass - ingesta free fat free body mass of adult in December (in kg) Age - age of adult animal (years) Recruitment - the number of animals an adult animal recruited in the autumn SpringCapDate - the date the adult animal was captured in the spring. SpringWeight - mass of adult (in kg) in March SpringFat - body fat of adult (% ingesta free body fat) in March SpringLeanMass - ingesta free fat free body mass of adult in March (in kg) change - the change in fat between March and December for an adult animal in a given year. precip - Values represent the cumulative precipitation in centimeters on an adult animals summer range during a given year. Precipitation was extracted using daily precipitation estimated from the Daily Surface Weather and climatological summaries (DAYMET) at the home range of each deer. Precipitation from Daymet is recorded in mm, we converted to cm for this dataset. estimate - the population estimate during a given year (should be multiplied by 100) percap.precip - the per capita precipitation for an adult animal in a given year; calculated as precip (cm)/estimate fawnsex - the sex of the fawn FawnMass - the mass of the fawn in December (kg) FawnLeanMass - ingesta free fat free body mass of the fawn in December (in kg) FawnFat - fat (% ingesta free body fat) of the fawn in December age2 - age of the mother squared change_mass - change in body mass of the adult between December and march Neonatemass - mass of the fawn at birth j.bday - Julian birthdate of the fawn fawn.masschange - change in mass of the fawn from birth to December uid - unique id of the mother u_fawnid - unique id of the fawn