  We present a numerical method that allows a formation of communicating agents
to target the boundary of a time dependent concentration by following a time
dependent concentration gradient. The algorithm motivated by \cite{MB, BKM},
allows the agents to move in space in a non-stationary environment. Our method
is applicable to finding the boundary of any regular surface and may be of
interest for for studying motions of swarms in biology, as well as to
engineering applications where boundary detection is an issue.
