10.5061/DRYAD.C2FQZ6192
Sankararaman, Vishnupriya
0000-0003-2410-4579
Pennsylvania State University
Dalvi, Shashank
Centre For Wildlife Studies
Miller, David
Pennsylvania State University
Karanth, Krithi
Centre For Wildlife Studies
Local and landscape characteristics shape amphibian communities across
production landscapes in the Western Ghats
Dryad
dataset
2021
FOS: Natural sciences
National Science Foundation
https://ror.org/021nxhr62
1265223
Oracle (United States)
https://ror.org/006c77m33
Karanth
2021-11-06T00:00:00Z
2021-11-06T00:00:00Z
en
119506 bytes
3
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Global tropical forests have been modified and fragmented by commodity
agroforests, leading to significant alterations in ecological communities.
Nevertheless, these production landscapes offer secondary habitats that
support and sustain local biodiversity. In this study, we assess community
level and species-specific responses of amphibians to land management in
areca, coffee and rubber, three of the largest commodity agroforests in
the Western Ghats. A total of 106 agroforests across a 30,000
km2 landscape were surveyed for amphibians using a combination of visual
and auditory encounter surveys. We used a Bayesian multi-species occupancy
modeling framework to examine patterns of species richness, beta
diversity, dominance structure and individual species occupancies. The
influence of biogeographic variables such as elevation and latitude as
well as microhabitat availability of streams, ponds and unpaved plantation
roads were tested on amphibian species occupancy. Coffee agroforests had
the highest species richness and lowest dominance when compared to areca
and rubber. Beta diversity was highest in areca for within agroforest
measures. Compared across agroforests, coffee had highest beta diversity
with areca and rubber. Both elevation and latitude showed an overall
positive association with amphibian occupancy although species-specific
responses varied considerably. Microhabitat availability was one of the
strongest predictors of amphibian occupancy, with mean community response
being positive with presence of water bodies and roads. Pond presence
increased species richness per site by 37% (species-specific responses in
occupancy ranged from -2.7% to 327%). Stream presence alone did not change
species richness but species-specific response ranged from -59% to 273%).
Presence of plantation roads also increased species richness by 21.5%
(species-specific response range -82% to 656%). Being unpaved with little
vehicular traffic, plantation roads seem to provide additional habitats
for amphibians. Presence of all three microhabitats at a site increased
species richness by 75%. Our study highlights the importance of land
management strategies that maintain diverse native canopy and freshwater
bodies and other microhabitats in sustaining amphibian fauna. Market
driven land-use change from coffee to other agroforest types will have
detrimental effects on amphibian communities and their long-term
sustainability in the Western Ghats.
We surveyed 106 unique agroforests (33 areca, 33 coffee, and 40
rubber). Surveys were conducted between June and September, in the monsoon
season, when amphibians are most active. Three teams of two trained
observers conducted systematic, time-constrained searches between 19:00
and 23:00 hours. The length of the survey varied based on the size of the
site from 30 minutes to 300 minutes, with an average survey time of 93
minutes per site. The observers walked at a consistent pace, in a single
direction, along foot paths, roads, cultivated areas, and water
bodies. Observers recorded all frogs detected using visual and auditory
encounter surveys (VES/ AES). Encounter of a species by either method was
considered as a detection and mid to high canopy species were only
observed through auditory surveys. There were no spatial constraints set
on auditory detections. We attempted to identify every individual
encountered to the species-level based on external morphology and acoustic
characteristics. This data consists of 26 species which were reliably
identified in the field.