Shrub density effects on the community structure and composition of a desert animal community

Positive interactions between shrubs and animals are frequent in desert
ecosystems. Shrub canopies can provide refuge to some animal species from
predators and shelter from stressful environmental conditions by
ameliorating high temperatures through lowering the amplitude of
variation. Consequently, there have been many contrasts of shrub versus
open effects; however, we extend this approach further by testing these
effects on a gradient of shrub densities in the Carrizo National Monument,
California. We tested the hypothesis that shrub density is a
landscape-level predictor of vertebrate community composition and
structure. We used camera traps, transects, and focal observations to
estimate animal density and composition, alongside the deployment of
temperature sensors. Plots were established within shrub patches ranging
from 0 to 12 shrubs per 10m radius. Plots with relatively higher shrub
densities had increased the abundance and richness of vertebrate animal
species. Temperature and residual dry matter were also important mediators
of animal density and richness. Shrub cover was also an important driver
of animal communities but we propose that shrub density is a more rapid
proxy for vegetation effects in deserts relevant to wildlife
conservationists, and managers.