Does a lack of juveniles indicate a threat? Understanding body size distributions in a group of long-lived vertebrates

This data set contains size and/or sex data from 41,021 freshwater turtles
from 38 species and 428 populations located in parts of Australia both
with and without introduced foxes, as well as populations in the United
States of America, which naturally have raccoons (Procyon lotor), foxes,
and other nest predators. The goal was to examine population-level body
size distributions to establish a baseline for “typical” turtle
populations and test whether populations that are exposed to introduced
foxes have proportionately fewer juveniles compared to both AU populations
that lack introduced foxes and USA populations that are naturally exposed
to nest predators. We additionally conducted analyses on the biases of
trapping methods, effects of sample size, and effects of water body type.
This data set was assembled by pooling the data from numerous researchers.