When a 3-manifold fibers over the circle it often does so in infinitely many ways, and this gives a kind of laboratory for studying Teichmuller spaces and mapping class groups in many surfaces at once. Farb-Leininger-Margalit proved an influential theorem showing that fibered 3-manifolds organize the mapping classes of "short" Teichmuller translation length in all genera. We prove an analogous theorem for Weil-Petersson translation length. The proof uses recent theorems on renormalized volume as well as good old fashioned 3-manifold topology from the 1980s.  Quadratic differentials come into the story in a couple of different ways that I will try to point out. Joint work with Leininger, Souto and Taylor.