  The interplay between shear and bulk viscosities on the flow harmonics,
$v_n$'s, at RHIC is investigated using the newly developed relativistic 2+1
hydrodynamical code v-USPhydro that includes bulk and shear viscosity effects
both in the hydrodynamic evolution and also at freeze-out. While shear
viscosity is known to attenuate the flow harmonics, we find that the inclusion
of bulk viscosity decreases the shear viscosity-induced suppression of the flow
harmonics bringing them closer to their values in ideal hydrodynamical
calculations. Depending on the value of the bulk viscosity to entropy density
ratio, $\zeta/s$, in the quark-gluon plasma, the bulk viscosity-driven
suppression of shear viscosity effects on the flow harmonics may require a
re-evaluation of the previous estimates of the shear viscosity to entropy
density ratio, $\eta/s$, of the quark-gluon plasma previously extracted by
comparing hydrodynamic calculations to heavy ion data.
