Abstract:
Species diversity and community structure of reptiles of selected agroecosystems
in Thrissur, Kerala was studied during January 2017 to May 2017. The agroecosystems
chosen for the study were Coconut Plantation, Cashew Plantation, Rubber Plantation,
Botanical Garden, Home garden and Wetland. Time-constrained visual encounter
survey was the method used for the study, and a total effort of 360 man hours were
spent in the field. The highest number of individuals were recorded from the Botanical
Garden with 159 individuals of reptiles. While, the species richness was highest in the
Coconut Plantation and Cashew Plantation with 11 species each. 18 species of reptiles
belonging to six families were observed during the study. This include six species of
geckos, four species of skinks, one agamid species and seven species of snakes. Bronze
Grass Skink Eutropis macularia, was the most abundant species. More reptiles were
recorded during night hours than morning hours.
Correspondence analysis was deployed to compare the reptilian diversity
between the habitats. Home garden and Wetland were found distinct in reptilian species
composition from the rest of the agroecosystems. The effect of habitat variables on the
presence of reptile species was analysed using canonical correspondence analysis.
Litter cover, litter depth, canopy height, canopy cover, shrub cover and herb cover were
found to influence the presence of the species Russell’s Kukri Snake Oligodon
taeniolatus. Relative humidity was found to influence the presence of the reptiles such
as Oriental Garden Lizard Calotes versicolor, Beddome’s Cat Snake Boiga beddomei,
Termite Hill Gecko Hemidactylus triedrus, Spotted House Gecko Hemidactylus
brookii, Common Wolf Snake Lycodon aulicus, Trinket Snake Coelognathus helena
and Checkered Keelback Xenochrophis piscator. Maximum temperature was found to
influence the presence of reptiles such as Common Krait Bungarus caeruleus,
Dussumier’s Litter Skink Sphenomorphus dussumieri and Bark Gecko Hemidactylus
leschenaultii.
Two species of reptiles that are endemic to Western Ghats such as Beddome’s
Cat Skink Ristella beddomii and Dussumier’s Litter Skink Sphenomorphus dussumieri
were recorded. Of these, the report of the Ristella beddomii from the KAU campus is
of interest, as it has been reported from a lower altitude (50m) than the already known
lowest altitude range (400m) for this species.
This documentation is important as it highlights the significance of
agroecosytems in conserving the reptilian fauna of the region, including some of the
Western Ghats endemic species.
