  We report a new analysis of the isospin splittings within the decuplet baryon
spectrum. Our numerical results are based upon five ensembles of dynamical
QCD+QED lattices. The analysis is carried out within a flavour-breaking
expansion which encodes the effects of breaking the quark masses and
electromagnetic charges away from an approximate SU(3) symmetric point. The
results display total isospin splittings within the approximate SU(2)
multiplets that are compatible with phenomenological estimates. Further, new
insight is gained into these splittings by separating the contributions arising
from strong and electromagnetic effects. We also present an update of earlier
results on the octet baryon spectrum.
