Data from: Cost of dispersal in a social mammal: body mass loss and increased stress

Dispersal is a key process influencing the dynamics of socially and
spatially structured populations. Dispersal success is determined by the
state of individuals at emigration and the costs incurred after
emigration. However, quantification of such costs is often difficult, due
to logistical constraints of following wide-ranging individuals. We
investigated the effects of dispersal on individual body mass and stress
hormone levels in a cooperative breeder, the meerkat (Suricata suricatta).
We measured body mass and faecal glucocorticoid metabolite (fGCM)
concentrations from 95 dispersing females in 65 coalitions through the
entire dispersal process. Females that successfully settled lost body
mass, while females that did not settle but returned to their natal group
after a short period of time did not. Furthermore, dispersing females had
higher fGCM levels than resident females, and this was especially
pronounced during the later stages of dispersal. By adding information on
the transient stage of dispersal and by comparing dispersers that
successfully settled to dispersers that returned to their natal group, we
expand on previous studies focusing on the earlier stages of dispersal. We
propose that body mass and stress hormone levels are good indicators to
investigate dispersal costs, as these traits often play an important role
in mediating the effects of the environment on other life-history events
and individual fitness.