The roosting
ecology of most waterbird species is poorly known and even less is known from southern
Asia, where many species inhabit human-modified areas. Roosting ecology of the
Black-headed Ibis (Threskiornis
melanocephalus) was studied in urban and rural settings in southern
Rajasthan, India. Analyses focused on assessing whether site characteristics
varied between nest sites, urban and rural roost sites, and paired sites (i.e.,
a waterbird roost site near Black-headed Ibis roosts but without Black-headed
Ibis). Additionally, the hypothesis that factors affecting Black-headed Ibis
numbers at roosts would be similar at urban and rural sites was tested. Tree
characteristics (canopy cover, girth at breast height) were different (P < 0.05) between nest and roost
sites. Urban roost sites experienced 2.3 times greater disturbance than rural
roost sites. Paired site characteristics were similar to urban roost sites
(multi response permutation procedure, significance
of δ = 0.3), but were dissimilar to rural roost sites. Co-occurring
roosting bird assemblages were significantly different between roosts and
paired sites (significance of δ < 0.01)
in urban and rural settings. Black-headed Ibis numbers at urban roosts were
influenced by multiple variables, but models showed considerable ambiguity at
rural sites. Results strongly suggest that including roost sites in a species
status assessment is important.
Journal Article
In press
Roosting ecology of Black-Headed Ibis (Threskiornis
melanocephalus)
in urban and rural areas of southern Rajasthan, India
Waterbirds 42(1).