Does population density influence the welfare of wild newts?
Grantee: Luiza Figueiredo Passos
Institution: Liverpool John Moores University, United Kingdom
Grant amount: $158,060
Grant type: Challenge grants
Focal species: Great crested newt (Triturus cristatus)
Conservation status: Least concern
Disciplines: Physiology, animal behavior, herpetology
Research location: United Kingdom
Project summary
The project seeks to determine how the welfare of the widespread species of great crested newts, Triturus cristatus, is influenced by population density in order to help determine how management practices can foster the welfare of individuals. Based on previous studies that have shown that population size and density correlate negatively with body condition and adult survivorship, this study will test the hypothesis that optimal conditions for population sustainability (i.e., conditions that result in higher juvenile survival) could be suboptimal at the individual level, and consequently negative for welfare. The project will study the welfare of newts in populations with varying densities at different locations in England. Welfare will be assessed using the Five Domains model of animal welfare by collecting measures of health (presence of injuries or diseases, corticosterone level, and telomere attrition), behavior (expression of abnormal behavior, flight response, behavioral restriction), and nutrition (body condition, food availability). Environmental parameters (water quality, shelter availability, predator pressure, proximity to anthropogenic threats) will also be collected to assess the relationship between habitat quality and welfare.
Why we funded this project
We funded this project because it will assess density-dependent welfare using a diverse battery of indicators. It is especially exciting to see them applied to a highly abundant amphibian, as the overwhelming majority of wild animal welfare projects have focused on mammals or birds. The proposing team is also very well qualified and has previously been funded by Wild Animal Initiative, which makes them well-suited to take on an analytically challenging project to disentangle influences of population density on newt welfare.
Find Luiza’s other project, studying house sparrows, here.