To cooperatively carry food, orders of magnitude larger than their own size and weight, single ants conform their efforts and coordinate their motion to reach their collective goal, the nest. In this study we look at the dynamics of collective transport when the ants motion is frustrated by an obstacle. We compare analytical description of the ant-load system to computer based stochastic simulations. The results show how changes in internal interactions and information fluxes yield different bi-stable dynamical phases, and demonstrate how internal noise sources affect the dynamics. The results display agreement with recent experiments and observations.