Comparison of niche overlaps and niche width between species at
broad and regional scales
Broad scale: At the larger spatial scale of Ladakh, the
elliptical projections of niche space indicated that the three species
separated best along the first two dimensions, albeit with significant
overlaps (Figure 4). The niche overlap analysis suggested that OL was
very likely to be found in the microhabitats that are inhabited byON (mean = 40 %) and OM (mean= 50%) (Figure 5).Both OM and ON were less likely to be found in microhabitats inhabited
by other species (mean < 15%) (Figure 5). The n-dimensional
niche width constructed was different across species
(Pr(>F) = <2e-16 ***, F value = 6541, df = 2),
with OL having the smallest niche, OM having an intermediate-sized
niche, and ON having the largest niche as evidenced by Turkey HSD tests
(Figure 6).
Regional scales: When the species were subdivided based on
location (OL South-East Ladakh, ON North-West Ladakh, ON South-East
Ladakh, OM North-West Ladakh, OM South-East Ladakh), elliptical
projection of niche spaces indicated significant overlaps between niches
of ON and OL in the South-East, the niche of OM in the South-East and
the North-West, and ON in North-West Ladakh being distinct with no
significant overlaps with any other niche (Figure 7). The niche overlap
analysis suggested that all species across geographic areas had unique
niches and were unlikely to be found in microhabitats of other species
(Figure 8). The niche width of species across geographic areas was
different at the regional scale (Pr(>F) = <2e-16
***, F value = 9570, df = 4) and revealed contrasting patterns to those
recovered at the broad scale. Tukey HSD tests suggested that the niche
width of OM in the North-West was the largest, followed by ON and OL in
the South-East, having the second and third largest niches, respectively
(Figure 9). The niche width of ON and OM in the South-East did not
differ (diff = 2.68, p adj = 0.089) and were among the smallest niches
in comparison (Figure 8).