escaped possible Wood Duck x Chestnut Teal or Wood Duck x Laysan Duck hybrid,
The identification of this hybrid is unknown. Wood Duck x Chestnut Teal has been suggested and at the moment we have very little to go on. It may be the correct ID but further examples of this or other similar hybrids will probably be necessary before we can reach any clear conclusions.
Joern has unearthed a description of another example of a bird identified as Wood Duck x Chestnut Teal hybrid, along with a photo of the mounted specimen (which is unfortunately no longer available), and that one apparently looked rather different. That might indicate that we need a different solution for this bird and one idea Joern has suggested is Wood Duck x Laysan Duck.
escaped possible Wood Duck x Chestnut Teal or Wood Duck x Laysan Duck hybrid (same bird as in photo ID 0883 above),
Wood Duck Aix sponsa
Laysan Duck Anas laysanensis
Chestnut Teal Anas castanea