  We have studied the entanglement of identical fermions in two spatial regions
in terms of the Berry phase acquired by their spins. The analysis is done from
the viewpoint of the geometrical interpretation of entanglement, where a
fermion is visualized as a scalar particle attached with a magnetic flux
quantum. The quantification of spin entanglement in terms of their Berry phases
is novel and generalises the relationship between the entanglement of
distinguishable spins and that of delocalised fermions.
