Abstract:
The efficiency of communication between animals is determined by the perception range of
signals. With changes in the environment, signal transmission between a sender and a
receiver can be influenced both directly, where the signal’s propagation quality itself is
affected, and indirectly where the senders or receivers’ behaviour is impaired, impacting for
example the distance between them. Here we investigated how meerkats (Suricata suricatta)
in the Kalahari Desert adjust to these challenges in the context of maintaining group
cohesion through contact calls. We found that meerkats changed their calling rate when signal
transmission was affected indirectly due to increased dispersion of group members as
during a drought, but not under typical wet conditions, when signal transmission was directly
affected due to higher vegetation density. Instead under these wetter conditions, meerkats
remained within proximity to each other. Overall, both direct and indirect environmental
effects on signal perception resulted in an increased probability of groups splitting. In conclusion,
we provide evidence that social animals can flexibly adjust their vocal coordination
behaviour to cope with direct and indirect effects of the environment on signal perception,
but these adjustments have limitations.