  We analyze the dynamics of a four-dimensional null hypersurface in a
five-dimensional bulk spacetime with Einstein-Yang-Mills fields. In an
appropriate ansatz, the projection of the field equations onto the hypersurface
takes the form of conservation laws for relativistic hydrodynamics with global
non-abelian charges. A Chern-Simons term in the bulk action corresponds to
anomalies in the global charges, with a vorticity term arising in the
hydrodynamics. We derive the entropy current and obtain unique expressions for
some of the leading-order transport coefficients (in the abelian case, all of
them) for arbitrary equations of state. As a special case and a concrete
example, we discuss the event horizon of a boosted Einstein-Yang-Mills black
brane in an asymptotically Anti-de-Sitter spacetime. The evolution equations in
that case describe the hydrodynamic limit of a conformal field theory with
anomalous global non-abelian charges on the Anti-de-Sitter boundary.
