Data from: Nonlinear scaling of foraging contacts with rodent population density

Density-dependent shifts in population processes like territoriality,
reproduction, dispersal, and parasite transmission are driven by changes
in contacts between individuals. Despite this, surprisingly little is
known about how contacts change with density, and thus the mechanisms
driving density-dependent processes. A simple linear contact-density
function is often assumed, but this is not based on a sound basis of
empirical data. We addressed this question using a replicated,
semi-natural experiment in which we measured contacts at feeding stations
between multimammate mice, Mastomys natalensis, across ten distinct,
linearly increasing densities between 10 and 272 animals/ha. Unexpectedly,
unique contacts increased not linearly but sigmoidally with density, which
we attribute to the species’ scramble competition mating system,
small-scale dominance/avoidance and absence of territoriality. These
results provide new insights into how species’ characteristics can relate
to density-dependent changes in contacts, and the unexpected shape of the
contact-density function warrants that density-dependence in ecological
models, such as parasite transmission models, must be parameterized with
care.