attached
Introduction: Calotes nigrilabris is an endemic, endangered lizard species, restricted to a
few localities in the central highlands of Sri Lanka and is the only agamid species found in
montane high altitude grasslands of the island. This study was focused on the microhabitat
preference of this species to help conservation and management of its small populations.
Association of endangered C. nigrilabris with the “wet patana” grasslands of Horton Plains
National Park has long been observed and it was interesting to study how this species
utilize this unique grasslands habitat which was subjected to human interferences from
time to time.
Methods/ Materials/Methodology: What were the main research methods you
used? Microhabitat preference of Calotes nigrilabris inhabiting the “wet patana”
grasslands of Horton Plains National Park was studied utilizing visual encounter surveys
along 3 fixed length line-transects of 200m each from January to December of 2016. When
the lizards were observed, microhabitat parameters in which they were seen were
recorded by placing 1 x 1 m quadrates (occupied quadrates, 303) taking the perching site
of the lizard as the center. Availability of different microhabitat conditions were studied
using random 1 x 1 m quadrates (unoccupied quadrates, 320) along the transects.
Variables of random unoccupied and occupied quadrates were compared using MannWhitney U-test and significantly different variables of occupied quadrates were further
analyzed using Principal Components Analysis (PCA).
Results/ Findings/Argument Development: What are the main results/findings of
your study? There was a significant difference between available habitat variables and
occupied microhabitat variables (Mann-Whitney U-test, p < 0.05) indicating that C.
nigrilabris was selective in its microhabitat utilization. Amount and type of vegetation was
the main determining factor of microhabitat preference of this species. Microhabitats with
high percentage cover of Ulex europaeus (PC1, 0.606) and Rhododendron arboretum
(PC2,-0.603; PC3, -0.513) were preferred by C. nigrilabris. Bare soil percentage, ambient
temperature, relative humidity and soil moisture percentage were also significantly
different in occupied quadrates.
Discussion/Synthesis and conservation relevance: Discuss and synthesise your
results and the relevance of your findings for conservation practice/science. The
results of this study indicate that C. nigrilabris is selective and well adapted for the
utilization of grassland microhabitats of Horton Plains National Park. Furthermore
microhabitats with rich vegetative cover of Ulex europaeus and Rhododendron arboretum
were providing these lizards protection from their predators and also serve as rich sources
of prey species. Interestingly Ulex europaeus is considered an invasive species. Therefore
this study provides important insights with respect to microhabitat preference of
endangered C. nigrilabris for the conservation and management of the species as well as
its natural habitat as a whole