  It is shown that each conservative nonsingular Bernoulli shift is either of
type $II_1$ or $III_1$. Moreover, in the latter case the corresponding Maharam
extension of the shift is a $K$-automorphism. This extends earlier results
obtained by Z.~Kosloff for the equilibrial shifts. Nonequilibrial shifts of
type $III_1$ are constructed. We further generalize (partly) the main results
to nonsingular Markov shifts.
