Sublethal effects of a mass mortality agent: Pathogen-mediated plasticity of growth and development in a widespread North American amphibian

Amphibians exhibit diverse responses to environmental challenges, but their responses to infection risk remain poorly understood. This study investigates how the presence of ranavirus, a deadly viral pathogen, affects growth, development, and resource allocation in wood frog (Rana sylvatica [Lithobates sylvaticus]) tadpoles. Using three years of pond survey data from a wood frog metapopulation in northeastern Connecticut, USA, we compared tadpole physiological rates across three scenarios: ranavirus-free ponds, ponds with sustained ranavirus infection, and ponds experiencing ranavirus die-offs. In ranavirus-positive ponds, tadpoles exhibited increased growth and resource allocation early in their development. These differences waned following die-off events in some ponds but persisted where widescale infection did not lead to die-off. This study provides evidence that an important disease agent appears to induce growth and developmental responses in its host that may help tadpoles survi..., Pond Surveys
Ranavirus surveys spanned ~mid-April to mid-July each year, during which we sampled each pond at least once every two weeks. At each visit, we collected up to 20 live wood frog tadpoles via timed dip net surveys with durations based on estimated pond area (m2) and estimated tadpole density per unit effort (Werner et al. 2007; \"rasy_density\" column in dataset). Density surveys were not conducted on 34 occasions (14% of sampling events) in our analysis dataset. When surveys were missed due to early season hatchling clustering near the oviposition site (~76% of cases), we used density values from the following survey ~two weeks later. For surveys missed due to other reasons (e.g., rain, equipment failures; ~14% of cases), we estimated tadpole densities as the average from the nearest surveys before and after the missing session. If both neighboring surveys were unavailable, we used the density from the most recent survey. We also recorded the presence of the predatory salamand..., , # Data from: Sublethal effects of a mass mortality agent: pathogen-mediated plasticity of growth and development in a widespread North American amphibian

[https://doi.org/10.5061/dryad.j9kd51cnq](https://doi.org/10.5061/dryad.j9kd51cnq)

## Description of the data and file structure

This directory contains data and code from:

Billet & Skelly (2025). Sublethal effects of a mass mortality agent: pathogen-mediated plasticity of growth and development in a widespread North American amphibian. [https://doi.org/10.3389/famrs.2025.1529060](https://doi.org/10.3389/famrs.2025.1529060)

## Files and variables

### File: Billet_RVallocation_data_archive_Oct2024.zip

Description: Compressed archive containing all data, code, and project files needed to reproduce the analysis. Contents include:

* RVallocation_data_archive_Oct2024.csv — Primary dataset (described below).
* RVallocation_CodeFile_Oct2024.R — R script to replicate all analyses. Instructions are provided inline as comments.
* Billet_..., ,