  With current magnetic field shielding and high precision detection in dipolar
spinor Bose-Einstein condensates, it is possible to experimentally detect the
low or zero field nonsecular dipolar dynamics. Here we analytically investigate
the zero-field nonsecular magnetic dipolar interaction effect, with an emphasis
on magnetization dynamics in a spin-1 Bose-Einstein condensate under the single
spatial mode approximation within the mean field theory. Due to the biaxial
nature of the dipolar interaction, a novel resonance occurs in the condensate
magnetization oscillation, contrast to the previous assumption of a conserved
magnetization in strong magnetic fields. Furthermore, we propose a
dynamical-decoupling detection method for such a resonance, which cancels the
stray magnetic fields in experiments but restores the magnetization dynamics.
Our results shed new lights on the dipolar systems and may find potential
applications beyond cold atoms.
