We categorised the abundance of these
three nest-site categories into five abundance
classes as follows: 1 = 0–2 pieces of given variable within average measured sample square, 2 =
3–4 pieces, 3 = 5–8, 4 = 9–20, and 5 ≥ 20 pieces.
We used the categorical variables as environmental data in multivariate analyses (see below).
We classified the microhabitat of each nest
found as belonging to one of the above three nest
site categories or to one of the following categories, here called collectively as “other sites”:
mounds constructed of needles or pieces of
grass, moss or other vegetative material; earthen