Activity Budget and Feeding Behaviour of Lesser Adjutant (Leptoptilos Javanicus) in Central Lowland Nepal
Date
2023
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Department of Zoology
Abstract
An activity budget provides a quantitative description of how animals spend their time
engaging in various activities such as foraging, maintenance and reproduction that
directly relates to an animal's metabolism, making it a crucial aspect of studying
behavioural ecology. Lesser adjutant Stork ((Leptoptilos javanicus) is a globally
vulnerable species with declining population and increasing threats. Hence, its activity
budget and foraging behaviour was studied for two seasons [monsoon (August 2022)
and winter season (January 2023)] in Chitwan and Rupandehi-Kapilvastu area to find
the seasonal behavioural activities and factors affecting its feeding success. Extensive
road survey method was used to collect the LAS behavioural video footage and
activity budget was prepared. Lesser Adjutant Stork spent maximum time foraging
(mean 9.97 ± 8.25 min) followed by resting, vigilance, maintenance, other and
locomotion activity. There was a variation in the time spent by LAS on foraging and
resting in between two seasons [foraging behaviour (t-value = 8.203, df = 237, p
<0.05) and resting behaviour (t = 8.341, df = 140, p<0.05)]. Time spent for foraging
was higher in monsoon (1565.56 min, 78% of total time duration) while time spent on
resting (751.03 min, 27% of total duration) was higher in winter season. LAS used
visual mode (96%) of foraging rather than tactile (4%). The snails (n = 477) was
major prey species followed by insects (n = 73), crabs (n = 19), fish (n = 15), frog (n
= 8), snake (n = 9), lizard (n = 3), carcasses (n = 2) and mouse (n = 1). Distance to
road (Estimate = -0.0022 ± 0.0009, p = 0.0171) and the distance to wetland (Estimate
= 0.0013 ± 0.0006, p = 0.0426) are influencing factors for feeding success on LAS.
Description
Keywords
Feedng behavior, Reproduction