DOI: 10.5061/dryad.sxksn03h0
title: Data and code from: Climate and species traits give rise to complex phenological dynamics

description: Climate change has substantially shifted the phenology of organisms. These
 shifts vary across species and habitats and are shaped by species natural
 history traits and local environmental conditions, yet the relative
 importance of these drivers remains unclear. Moreover, climate can have
 diverse effects on different aspects of phenology, such as the timing and
 duration of activity, but this complexity is rarely captured by commonly
 used phenological metrics. We used multidecadal butterfly surveys and
 climate data from five montane sites spanning an elevational gradient to
 investigate how climate affects different aspects of annual flight period
 of 135 butterfly species. Using a hierarchical Bayesian framework, we
 modeled annual probability of occurrence distributions for species using
 polynomial models that capture changes in abundance, timing, and length of
 flight. Spring maximum and minimum temperatures and winter precipitation
 were the best predictors of inter-annual variation in phenology. High
 winter precipitation, which usually comes in the form of snow, delayed
 phenology, while warmer spring maximum temperatures advanced phenology
 across elevations. Even modest increases in spring minimum (nighttime)
 temperatures caused strong phenological shifts. Climate effects varied
 among sites, among species within sites, and even among populations of the
 same species across sites, with particularly pronounced variation among
 species within a site. Variation in climate effects were slightly better
 explained by local climate than by natural history traits. Among natural
 history traits, voltinism and overwintering stage were particularly
 influential. Importantly, climate influenced different aspects of the
 flight period (e.g., timing versus duration) in distinct ways, with both
 natural history traits and local climate modulating these responses. Our
 findings highlight the often-overlooked importance of winter precipitation
 and nighttime temperatures in shaping phenology and demonstrate the value
 of considering the entire flight period, rather than distinct aspects
 alone, to improve our understanding and predictions of species response to
 climate change.
description: # Data and code from: Climate and species traits give rise to complex
 phenological dynamics Dataset DOI:
 [10.5061/dryad.sxksn03h0](https://doi.org/10.5061/dryad.sxksn03h0) ##
 Description of the data and file structure ### Files and variables This
 data archive contains three main folders, each with sub-folders that
 include a Data_README.txt file describing the content and usage of that
 sub-folder. #### File: DATA.zip **Description:** This file contains the
 long-term dataset, including presence/absence records for all butterfly
 species at each site from 1985 to 2023, species natural history traits,
 and climate data. #### File: Statistical_models.zip **Description:** This
 file contains the R scripts for all fitted models (both with and without
 climate variables) used to estimate annual occurrence distributions for
 each species at each site using a hierarchical Bayesian framework in stan.
 #### File: Figures_and_Tables.zip **Description:** This file contains the
 R scripts used to generate all main figures, supplementary figures, and
 tables. ## Code/software Software and packages used to run the scripts in
 this archive include: * R (version 4.2.2) * RStan package (Version 2.21.8)
 * Stan * loo package (Version 2.5.1) * Vegan package (version 2.6-8)