Scat Collection and Processing
From 5 May–5 October 2019 and 13 June–22 September 2020, we collected
all wolf scats encountered during fieldwork in IRNP. We collected fresh
scats (e.g., strong smell, moist, tracks present) at wolf radio-collar
GPS location clusters (Svoboda et al. , 2013) and on established
hiking trails (Fig. 1). We placed each scat in a plastic bag, recorded
the date and location (NAD83, UTM Zone 16N), and froze them for later
processing. We considered the collection date as the date of deposit,
although scats may have been up to 11 days old (Sanchez et al. ,
2004).
We processed and identified scat contents following Chenaux–Ibrahim
(2015). We placed frozen scats into nylon stockings, washed them in a
washing machine to remove digestible material and then dried the
contents in an oven. We spread the contents on a 21.5cm x 28cm plate,
overlaid a 25-point grid, and randomly selected one hair from each point
for microscopic identification (Ciucci et al ., 2004). We could
determine moose age class (adult or calf) until 15 September, when the
first molt occurs (Muller, 2006). After 15 September we identified all
moose hair as adult. Wolf hair may be ingested due to grooming or
cannibalistic activity, the latter resulting in a higher amount of hair
in scats (James, 1983; Muller, 2006). Therefore, we did not consider
wolf as a prey item unless we detected wolf hair at >10%
of points in a sample. We pooled all other prey (birds, muskrats, small
mammals, wolves, unidentifiable remains, and vegetation) into an
“other” category.