  The tunneling of quasiparticles (QPs) across Josephson junctions (JJs)
detrimentally affects the coherence of superconducting and charge-parity
qubits, and is shown to occur more frequently in magnetic fields. Here we
demonstrate the parity lifetime to survive in excess of 50$\,\mathrm{\mu}$s in
magnetic fields up to 1$\,$T, utilising a semiconducting nanowire transmon to
detect QP tunneling in real time. We exploit gate-tunable QP filters and find
magnetic-field-enhanced parity lifetimes, consistent with increased QP trapping
by the ungated nanowire due to orbital effects. Our findings highlight the
importance of QP trap engineering for building magnetic-field compatible hybrid
superconducting circuits.
