  We consider the Czir\'ok model for collective motion of locusts along a
one-dimensional torus. In the model, each agent's velocity locally interacts
with other agents' velocities in the system, and there is also exogenous
randomness to each agent's velocity. The interaction tends to create the
alignment of collective motion. By analyzing the associated nonlinear
Fokker-Planck equation, we obtain the condition for the existence of stationary
order states and the conditions for their linear stability. These conditions
depend on the noise level, which should be strong enough, and on the
interaction between the agent's velocities, which should be neither too small,
nor too strong. We carry out the fluctuation analysis of the interacting system
and describe the large deviation principle to calculate the transition
probability from one order state to the other. Numerical simulations confirm
our analytical findings.
