Data analysis from: Demographic consequences of changing body size in a terrestrial salamander

Changes in climate can alter individual body size, and the resulting
shifts in reproduction and survival are expected to impact population
dynamics and viability. However, appropriate methods to account for
size-dependent demographic changes are needed, especially in understudied
yet threatened groups such as amphibians. We investigated individual and
population-level demographic effects of changes in body size for a
terrestrial salamander using capture-mark-recapture data. For our
analysis, we implemented an integral projection model parameterized with
capture-recapture likelihood estimates from a Bayesian framework. Our
study combines survival and growth data from a single dataset to quantify
the influence of size on survival while including different sources of
uncertainty around these parameters, demonstrating how selective forces
can be studied in populations with limited data and incomplete recaptures.
We found a strong dependency of the population growth rate on changes in
individual size, mediated by potential changes in selection on mean body
size and on maximum body size. Our approach of simultaneous parameter
estimation can be extended across taxa to identify eco-evolutionary
mechanisms acting on size-specific vital rates, and thus shaping
population dynamics and viability.