DOI: 10.5061/dryad.1zcrjdg5v
title: Persistence of sub-clinical <em>Batrachochytrium dendrobatidis</em> infection in stream anurans in South Asia

description: Chytridiomycosis is caused by Batrachochytrium dendrobatidis (Bd) and
 contributes significantly to amphibian declines globally. It has affected
 more than 500 amphibian species on five continents. In South Asia, the
 Western Ghats is an amphibian biodiversity hotspot; however, the
 population status of anurans and their burden of chytridiomycosis are not
 well understood. Our aim was to understand pathogen prevalence, load, and
 its persistence in a stream anuran community in the Western Ghats. We
 carried out a capture-mark-recapture (CMR) programme in five ephemeral
 streams of the Tillari Conservation Reserve (TCR), Western Ghats, India,
 from 2018 to 2020 during the early (wet) and late (dry) recovery periods.
 We used quantitative Polymerase Chain Reaction (qPCR) to assign disease
 states - no (N), low (L), and High (H) levels to every anuran, based on
 the Bd loads detected. We constructed population models using CMR data
 from skittering frogs, with Program MARK, and estimated transition
 probability, apparent survival probability, and capture probability in
 each disease state. We found that the overall Bd prevalence was 74.6% in
 the community, with an average infection load of 49 to 700 zoospores/swab.
 Many anurans cleared infections between early (wet) and late (dry)
 recovery periods, while some maintained high infection loads. In
 skittering frogs, the infection states did not influence capture
 probabilities and apparent survival probabilities. The transition
 probability between infection states was random, and transitions from any
 disease state to low were more probable than transitions from any disease
 state to high or no disease states. The maintenance of a substantial
 burden of Bd in the anuran community with no apparent impact on their
 survival or capture probabilities suggests an effective pathogen
 transmission mechanism. As anurans continue to show a declining trend in
 the Asian tropics, investigation on the impacts of sub-clinical Bd
 infections in anurans needs impetus.
description: # Persistence of sub-clinical *Batrachochytrium dendrobatidis* infection
 in stream anurans in South Asia Dataset DOI:
 [10.5061/dryad.1zcrjdg5v](10.5061/dryad.1zcrjdg5v) ## Description of the
 data and file structure File: Field_Data_2018_to_2020.xlsx It contains
 data used for capture mark recapture of frogs from 5 stream segments in
 Tillari Conservation Reserve, Maharashtra, India, from 2018-2020. The data
 represent frogs that were captured and marked, and recaptured, that were
 &gt; 29 mm in snout vent length. Descriptions of the data are given below.
 Session : Odd numbers are Wet session, and even numbers are Dry session
 Stream : HB_Hevale Bridge, KA_Kharade, HV_Hevale village, GW_Ghatiwade,
 RW_Raniwade Visit : Total 5 visits each session R_N : Recapture( R ), and
 New Capture ( N ) Swabb : Yes taken ( Y ), and Not taken ( N ) Wt : Weight
 in grams SVL : Snout to Vent length in mm T : Vertical transect quadrant
 number B : Horizontal transect quadrant number DNA Serial No : DNA Serial
 No for DNA samples Mean Cp : qPCR Cp values Year : Year of collection
 Disease State : Positive ( P ), Negative ( N ), Not applicable ( NA )
 Species : EC = *Euphlyctis cyanophlyctis*, IS = *Indosylvirana caesari*,
 InC = *Indirana chiravasi*, NJ = *Nyctibatrachus jog* ## Code/software
 MARK, R version 4.4.1 ## Access information Other publicly accessible
 locations of the data: * Not applicable Data was derived from the
 following sources: * Not applicable