Fish-like pit patterns found for atomic force microscopy (AFM) image of grown GaAs(1 1 0) surface is investigated theoretically using the kinetic Monte Carlo (kMC) simulation technique. The anisotropic migration of adatoms indicated by the first principles calculation is included into the model as "virtual" one-component simulation. The result shows that the fish-like pits can be formed with a certain set of parameters in the kMC simulation. Moreover, the other sets of parameters show trench pits as a limit of long fish-like pits. The result shows us that the anisotropy of migration of adatoms during the growth makes the fish-like pattern of pits in the simulation. (c) 2007 Elsevier B.V. All rights reserved.