Demographic rates of wild bison

Demographic data were collected on wild bison in Yellowstone National Park to estimate population growth rate, annual survival probability, and fertility. Separate data files exist for each rate or probability. The data for estimating population growth rate include annual counts and management removals. The data for estimating survival and fertility are from adult female bison fit with radio collars. These data are applicable for estimating vital rates of plains bison in North America. Data were collected by the National Park Service.
, Counts and Managment Removals
Annual counts were completed during 1901-2024. Counts completed by winter surveys in the initial decades and aerial counts starting in the 1960s. Aerial counts generally occurred in summer. Management removals occurred in winter between counts. Removals were accounted for in estimating population growth rate.
We fit the data to a discrete time model of population growth: y~[t+1]~ = r (y~[t]-r[t]) + e, where y[t]~ is the count during year* t*, r~[t]~ is the removals occurring after count, and* e* is model uncertainty. Bayesian inference and Monte Carlo integration were used to estimate model parameters.
Age-specific survival
Age-specific annual survival probability was estimate from 166 female bison fit with radio collars during 1996-2015. Female bison were a minimum of two years of age at the time of collaring. 
We fit the data to binomial model with survival probability given by a linear combination of age using Bayesian inference and Monte Carlo..., # Demographic rates of wild bison

Dataset DOI: [10.5061/dryad.mkkwh71d5](https://doi.org/10.5061/dryad.mkkwh71d5)

## Description of the data and file structure

Data files included to complete analyses using Program R. 

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### Files and variables

#### File: birth_rate.csv

**Description:** 

##### Variables

* id: animal ID
* year: year
* age: age
* calf: A \"1\" indicates a calf was observed in close association with the dam including nursing. A \"0\" indicates a calf was never observed with the dam during the calving period. Animals were located at least weekly during the calving period. Estimates likely include some level of neonate loss.

#### File: female_age_specific_surv.csv

**Description:** Data file of annual survival observations of adult female bison. Each row of data includes the animal ID, year, age, and survival observation. The year followed the same structure as used for modeling population growth rate, beginning on June 1 of the previous year and ending on May 31 of ...,