  We investigate the polarons formed by immersing a spinor impurity in a
ferromagnetic state of $F=1$ spinor Bose-Einstein condensate. The ground state
energies and effective masses of the polarons are calculated in both
weak-coupling regime and strong-coupling regime. In the weakly interacting
regime the second order perturbation theory is performed. In the strong
coupling regime we use a simple variational treatment. The analytical
approximations to the energy and effective mass of the polarons are
constructed. Especially, a transition from the mobile state to the
self-trapping state of the polaron in the strong coupling regime is discussed.
We also estimate the signatures of polaron effects in spinor BEC for the future
experiments.
