Abstract:
Permanent changes caused due to agriculture have resulted in wide-ranging impacts on
amphibian diversity and abundance. Altered environmental conditions such as using chemical
fertilizer, insecticides, antibiotics, growth hormones, and soil erosion have pushed amphibians
to the end of their range of tolerance. Therefore, this study was designed to ascertain the
amphibian species diversity of an urban ecosystem: Nuwara Eliya, with the objective of
assessing the contribution of organic farming for the conservation of amphibian species. Two
different habitat types viz. a terrestrial habitat with an organic farm garden (OFG) and a habitat
with a non-organic farm garden (NOFG), were studied. Amphibian species inside the square
were recorded during the night (19:00 – 21:00) using 5m2 quadratic plots. For each new species
recorded within the plot, a new square was plotted adjacently, and observations were repeated
once a month for a period of 09 months from January - September 2019. As per the observations,
206 amphibians belonging to 06 species and 04 families were recorded within the area
representing critically endangered, endangered and least concern amphibian species. The
Simpson’s index and Shannon diversity index for OFG & NOFG were 0.34/0.36 and 0.53/0.07,
respectively. The most dominant species recorded were the common house toad (Duttaphrynus
melanosticus), small eared shrub frog (Pseudophilautus microtympanum), Mountane hour-glass
tree frog (Taruga eques), with relative abundances of 44.66%, 36.40% and 14.07%, respectively.
The globally critically endangered and endemic schmarda's shrub frog (Pseudophilautus
schmarda) was the least recorded species with a relative abundance of 0.48%, recorded when
heavy rains began in the area (September). The least diversity was recorded in NOFG with a
Shannon diversity index (0.53) and the highest (0.34) was recorded in OFG representing all six
recorded amphibian species including one critically endangered species, leaf nesting shrub frog
(Pseudophilautus femoralis) which was not recorded in NOFG. Therefore, it is evident that these
organic farm habitats act as wildlife refuges and neutralize the negative effects of non-organic
farming on amphibians to a certain extent. Thus, proper conservation plans should be
implemented through research to manage and improve the existing local habitats and thereby
protect the amphibians.
