DOI: 10.5061/dryad.6t1g1jx08
title: Drought and coyotes mediate mesopredator response to human disturbance

description: Mesopredators in western North America are facing major changes to their
 ecosystems, including drought and the expansion of human disturbance. To
 balance resource needs and risk-taking on the landscape, mesopredators are
 likely shifting their habitat use as well as their interspecies
 interactions. As part of a large-scale study to help evaluate responses of
 terrestrial wildlife to severe drought, the California Department of Fish
 and Wildlife surveyed mesopredator presence across 585 sites in the Mojave
 Desert and Central Valley ecoregions of California. This study spanned a
 drought year (2016) and a post-drought year (2017), providing the
 opportunity to investigate how drought and interspecific interactions may
 mediate spatial patterns of mesopredator occurrence across a continuum of
 human disturbance levels. We used single-season, single-species, and
 conditional two-species occupancy models to elucidate these relationships
 in both ecoregions. We examined occupancy and detection of coyotes (Canis
 latrans) and smaller mesopredators, including bobcats (Lynx rufus) in both
 ecoregions, raccoons (Procyon lotor) in the Central Valley, and desert kit
 foxes in the Mojave Desert (Vulpes macrotis arsipus). The presence of
 coyotes influenced the detection probability of all other mesopredator
 species, and the impacts of drought varied by species and ecoregion.
 Detection of mesopredators in the Central Valley was typically higher in
 2016, especially at low disturbance sites, suggesting species may have
 become more active during the drought to meet resource needs. However,
 detection of mesopredators in the Mojave Desert tended to increase after
 the drought, suggesting a response to an increase in resources (e.g.,
 prey). Coyotes in the Mojave Desert became more detectable in high human
 disturbance in 2016 and less detectable in 2017, possibly increasing
 activity during the drought in human-disturbed areas to obtain
 anthropogenic resources. Drought not only affects individual species and
 their relationships to human disturbance, but it can also impact their
 interspecies interactions and use of different landscape features.
description: This data represents presence/absence data for mesopredators
 based on camera trap surveys conducted at 266 sites in the Central Valley
 and 319 sites in the Mojave Desert of California in 2016 and 2017.
 Additional data included are non-standardized covariate values and real
 parameter estimates from occupancy modeling for mesopredators for
 scenarios of interest involding drought and human disturbance. 
description: There are separate detection histories for each individual
 mesopredator species in both ecoregions and then combined detection
 histories for coyotes and subordinate mesopredator species in both
 ecoregions. Detection history: 1 = species detected on
 this survey (survey = single day in Central Valley and within a 3-day
 survey period in Mojave Desert), 0 = species not detected during survey,
 NA = camera non-functional during survey (camera not aimed at bait for 24
 hrs, likely due to disturbance to the camera). These detection histories
 are followed by standardized values for covariates In
 two species files (CANLAT & other species code)  the two detection
 histories are combined, with the subordinate species (not coyote) coming
 first (column 1 = survey 1 for subordinate species, column 2 = survey 1
 for coyote, column 3 = survey 2 for subordinate species, column 4 = survey
 2 for coyotes, etc.). Covariates are standardized in
 detection histories so CV (Central Valley) and MD (Mojave Desert)
 covariates are included for raw covariate values. Did not include lag for
 coyote or bait for MD in the raw covariates (bait is just sequential from
 1 and lag is same in standardized values). <b>OVERALL
 KEY</b> MD =
 Mojave Desert CV =
 Central Valley CANLAT = Coyote (<i>Canis
 latrans</i>) LYNRUF = Bobcat (<i>Lynx
 rufus</i>) VULMAC = Kit fox (<i>Vulpes
 macrotis</i>) PROLOT = Raccoon (<i>Procyon
 lotor</i>) CV
 covariates: lat = latitude yr =  year (0 = 2016, 1 =
 2017) HD = measure
 of human disturbance (1-10) within a 1 km buffer of the camera at a
 site trees =
 proportion tree cover (including orchards) within a 1 km buffer of camera
 at a site water =
 water at site at time of camera deployment(1 = yes, 0 = no)
 d_water = distance to water
 (km) yr*HD =
 interaction with year yr*water = interaction of presence
 of water at a site with year  yr*d_water = interaction of
 distance to water at site with year j(1-27) = ordinal date on day of
 survey (e.g. j1 = ordinal date on first survey) <em>From detection
 history:</em> 3lag(1-27) = CV coyote Markov
 dependency (= 1 if coyote detected in past 3 days)
 MD covariates: elev = elevation (km)
 water = distance to
 water (km) HD =
 measure of human disturbance (1-10) within a 1 km buffer of the camera at
 a site YR = year (0
 = 2016, 1 = 2017) guzz = presence of guzzler at site
 (1 = guzzler on site, 0 = guzzler not on site) julian1 = ordinal date on day of
 first survey YR*HD
 = interaction of human disturbance at site with year YR*guzz = interaction of presence
 of guzzler at a site with year  YR*water = interaction of distance
 to water at site with year <em>From detection
 history:</em> b(1-9) = standardized bait day
 (same as day of survey = age of bait)
 Single/Two Species Parameter
 Estimates: <strong>Parameter</strong> Single p = detection probability Psi = occupancy probability Two PsiA = occupancy probability of species A (coyote) PsiBA = occupancy probability of species B (subordinate species: bobcat, raccoon, or kit fox) if species A is present (same as PsiBa) PsiBa = occupancy probability of species B (subordinate species: bobcat, raccoon, or kit fox) if species A is absent (same as PsiBA) pA = detection probability of species A (coyote) is species B is absent (same as rA) rA = detection probability of species A (coyote) if both species are present (same as pA) pB = detection probability of species B if species A is absent   rBA = detection probability of species B if species A is present and detected (same as rBa) rBa = detection probability of species B if species A is present and not detected (same as rBA) <strong>Human Disturbance: Measure (1-10) of human disturbance (footprint) within 1 km buffer of site</strong> Central Valley Low = 4 Average =  8.1 High = 10 Mojave Desert Low = 1 Average = 3.4 High = 6.8 SE: Standard Error LCI = lower 95% confidence interval  UCI = upper 95% confidence interval  <em>From two species:</em> Sub. species = subordinate species, species B (dominant species is always the coyote, Species A)