Small Mammal Prey Study for the Mexican Spotted Owl at Two Locations at Los Alamos National Laboratory

Technical Report · Tue Feb 01 04:00:00 EST 2022

DOI:https://doi.org/10.2172/1846121· OSTI ID:1846121

Gadek, Chauncey Ryland ^[1]; Velardi, Milu Sue ^[1]

---

1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

In New Mexico, Mexican spotted owls (Strix occidentalis lucida) are typically found in rocky canyons consisting of mixed-conifer forests that have experienced minimal human disturbance. At Los Alamos National Laboratory (LANL), Mexican spotted owls have been found breeding and foraging in habitats consistent with their known biology, but face the impact of human encroachment in the surrounding upland habitat. Little is known about the prey base present within the Laboratory’s vast forests. In anticipation of expanding human development in proximity to known occupied owl habitat, the goal of our study was to evaluate the small mammal prey base available to Mexican spotted owls at the Laboratory and to assess prey availability, diversity and composition. We sampled two study plots within the Laboratory’s forests for small mammals in 2021. Study plots were situated in conifer, deciduous, mixed conifer-deciduous and mixed oak. Our small mammal trapping efforts and SCR modeling revealed site-specific differences in prey base diversity, abundance and density between the unoccupied Pajarito Canyon and nearby occupied Mortandad Canyon site. These results highlight how managing tracts of land for small mammal prey base may overlap with goals set forth by researchers for Mexican spotted owl habitat needs. We recommend further trapping efforts to better understand prey availability in occupied and unoccupied sites at LANL as well as further investigation of prey selection through the dissection of pellets found in the areas surrounding known nesting locations.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: 89233218CNA000001
• OSTI ID: 1846121
• Report Number(s): LA-UR-22-21422
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
59 BASIC BIOLOGICAL SCIENCES