  Recent VLA observations pointed at dwarf spheroidal (dSph) galaxies in the M
81 group reveal a hitherto hidden population of extremely low mass (~1e5 Msol)
HI clouds with no obvious optical counterparts. We have searched 10 fields in
the M81 group totalling 2.2 square degree, both targeting known dwarf
spheroidal galaxies and blank fields around the central triplet. Our
observations show that the new population of low-mass HI clouds appears to be
confined to a region toward the South-East of the central triplet (at distances
of ~100 kpc from M 81). Possible explanations for these free-floating HI clouds
are that they are related to the dSphs found to the South-East of M 81, that
they belong to the galaxies of the M 81 triplet (equivalent to HVCs), that they
are of primordial nature and provide fresh, unenriched material falling into
the M 81 group, or that they are tidal debris from the 3-body interaction
involving M 81-M 82-NGC 3077. Based on circumstantial evidence, we currently
favour the latter explanation.
