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Foraging behavior of endemic Sri Lanka Dull-blue Flycatcher (Eumyias sordidus) was studied
in the tropical montane cloud forests of Horton Plains National park (HPNP), situated in the
highland plateau of the Nuwara Eliya District from July 2015 to July 2017. Three main
natural habitats were identified as Cloud Forest (CF), Cloud Forest Die-back (CFD) and
Grassland (GL) associated with HPNP. Focal sampling method was used to study the foraging
behaviour of E. sordidus. Foraging individuals were observed directly or through a binocular
from 0600h to 1800h, on three consecutive days per month. Line transects and opportunistic
observations were used to obtain foraging data. Foraging plant types were identified by using
field guides. Total of 1694 foraging attempts were recorded during the study period.
Maximum number of foraging observations (60.14%) were recorded from CF and least
number of foraging observations (5.69%) were recorded from GL Habitat. Observed foraging
height was 4.18±2.77m (Mean±Standard Deviation) above ground and distance to the canopy
above the bird was 3.01±1.76m (M±SD). They preferred the trees with 6.04±2.75m (M±SD)
height, 0.73±0.41m (M±SD) average diameter-at-breast height and 1.71±0.71m (M±SD)
average trunk height in the montane forest habitat. E.sordidus diet consisted of prey (97.03%)
and fruits (2.97%). Prey were captured in Air (29.70%), ground (25.49%), leaves (15.59%),
moss (13.37%), twigs (6.44%), trunks (4.21%) and flowers (2.23%), substrates. Rubus
ellipticus and Rubus rugosus were the main feeding plants of E. sordidus. Aerial foraging
manoeuvre was identified as sallying (hawking). Four types (outward-sally-gleaning, upwardsally-gleaning, outward-striking and upward striking) of sally-gleaning capture techniques
were observed. Return-to-perch frequency was 26%. Ground foraging manoeuvres were
identified as ground-sally-gleaning, stand-ground-gleaning and hopping-ground-gleaning.
When the stationary prey was taken from the substrate while perching, simple-perch-gleaning
and landing-and-gleaning capture techniques were observed. The birds perched and picked at
fruits without sallying (76%) and occasionally some individuals ate only a portion of the fruit
without removing it from the plant (24%). Finding of the present study indicated that E.
sordidus utilized prey items along with fruits of two plant species belongs to family Rosaceae
which is indigenous to the montane cloud forests. The physical techniques of different prey
capture methods and standardized nomenclature for these techniques were suggested from this
study
