  By incorporating a large-scale shear flow into turbulent rotating convection,
we show that a sufficiently strong shear can promote dynamo action in flows
that in the absence of shear do not act as dynamos. Our results are consistent
with a dynamo driven by either the shear-current effect or by the interaction
between a fluctuating $\alpha$-effect and the velocity shear; they are though
inconsistent with either a classical $\alpha^2$ or $\alpha \omega$ mean field
dynamo.
