Zapus eDNA detection data

The New Mexico meadow jumping mouse (Zapus hudsonius luteus) is a riparian
obligate species native to the southwestern United States. The
species was listed endangered in 2014 due to habitat loss by over-grazing,
wildfire, and recreation. Jumping mice move through streamside, herbaceous
vegetation, and may leave behind cells suitable for environmental DNA
(eDNA) analysis. Use of eDNA to detect the presence of the animal from
vegetation can complement current survey approaches (live capturing, track
plating, camera trapping) while reducing field labor and the risk of harm
to the animal. We developed a highly sensitive, species-specific assay
that used quantitative real-time PCR. Through dilution tests, we
determined that only 3 copies of target DNA within a sample were necessary
for positive detection at 95% confidence. In our first
experiment, we assessed the specificity for our
assays through rigorous laboratory tests involving
closely related species ("Specificity test short assay"
& "Specificity test long assay"). To investigate
long-term persistence of eDNA on plant material ("Nest
detections"), we tested our assay on 4 nests that were sampled 3 to 6
months after a radio telemetry study identified them as day-use sites. We
then conducted a field survey to detect presence of New Mexico meadow
jumping mice using sterile cotton swabs to sample plants at 6 locations
along two occupied streams ("Field trial
detections"). We collected 60 swabs along transects. We
opportunistically swabbed plants (n = 9) following visual observation of
jumping mice on plants. We detected eDNA in 3 of 4 nests. From transects,
we detected 1 jumping mouse from a location where the animal was not
previously observed. We also detected jumping mice from 3 of 9 observation
informed (opportunistic) samples. We demonstrated that eDNA can persist on
nests that the animal contacted long after abandonment. eDNA detection
rate increased when informed by visual observation, and improvements to
sampling strategies may further increase detection rate. Our results
highlight the promise of using eDNA from terrestrial plants to detect
presence of riparian specialists.