  We study the degradability of fermionic Gaussian channels. Fermionic quantum
channels are a central building block of quantum information processing with
fermions, and the family of Gaussian channels, in particular, is relevant in
the emerging field of electron quantum optics and its applications for quantum
information. Degradable channels are of particular interest since they have a
simple formula that characterizes their quantum capacity. We derive a simple
standard form for fermionic Gaussian channels. This allows us to fully
characterize all degradable $n$-mode fermionic Gaussian channels. In
particular, we show that the only degradable such channels correspond to the
attenuation or amplitude-damping channel for qubits.
