  We investigate the effect of mechanical strain on the dynamics of thin
$\mathrm{MoS_2}$ nanodrum resonators. Using a piezoelectric crystal,
compressive and tensile biaxial strain is induced in initially flat and buckled
devices. In the flat device, we observe a remarkable strain-dependence of the
resonance line width, while the change in the resonance frequency is relatively
small. In the buckled device, the strain-dependence of the damping is less
pronounced, and a clear hysteresis is observed. The experiment suggests that
geometric imperfections, such as microscopic wrinkles, could play a role in the
strong dissipation observed in nanoresonators fabricated from 2-D materials.
