Habitat Area, Not Fragmentation, Associated with Breeding Bird Species Richness

Study Description

Riparian land cover in arid regions is likely to decrease in size and fragment in a warmer and drier future. We created a novel community model to examine whether species richness of breeding birds in canyons in Nevada, USA, increased with total riparian area or decreased with its fragmentation. Species richness was not associated with riparian fragmentation, but had a significant positive association with riparian area. Canyons with intermediate amounts of riparian area (~25 ha) may be management targets, as they are at most risk for species richness losses if riparian areas decrease with future climate change.

Photo 1. View of riparian patches (mostly Populus tremuloides, brighter green on the left side of image) amidst more xeric surrounding sagebrush shrub steppe in Stewart Canyon, Toiyabe Mountains, Nevada, USA. Photo credit: Frank Fogarty.

Photo 2. Red-naped Sapsucker (Sphyrapicus nuchalis), a species typically associated with riparian woodlands in our Great Basin (Nevada, USA) study area. Photo credit: Frank Fogarty.

These photographs illustrate the article “Multiple-region, N-mixture community model to assess associations of riparian area, fragmentation, and species richness” by F. A. Fogarty, J. D. L. Yen, E. Fleishman, R. Sollmann, and A. Ke published in Ecological Applications. https://doi.org/10.1002/eap.2698