  We consider the influence of local noise on a generalized network of
populations having positive and negative feedbacks. The population dynamics at
the nodes is nonlinear, typically chaotic, and allows cessation of activity if
the population falls below a threshold value. We investigate the global
stability of this large interactive system, as indicated by the average number
of nodal populations that manage to remain active. Our central result is that
the probability of obtaining active nodes in this network is significantly
enhanced under fluctuations. Further, we find a sharp transition in the number
of active nodes as noise strength is varied, along with clearly evident scaling
behaviour near the critical noise strength. Lastly, we also observe noise
induced temporal coherence in the active sub-network, namely, there is an
enhancement in synchrony among the nodes at an intermediate noise strength.
