a special about Shakleton this week commented that the first winter on the ice, Shakleton insisted that the men all crop their hair --and keep it cropped, to insure that everyone was keeping groomed, in the long winter. One member notes in a diary, 'we looked liked croppers, convicts all.'

american dictionaries only show two meanings for croppers, is the idea of a convict from the second (a fall from grace, as it were,) and perhaps a prison practice of shaving heads, to keep down on lice, etc?

and the second cropper is from crop and neck--i am guessing cockney rhyming slang, but for what?!

#1
a sharecropper.
#2
NOUN: 1. A heavy fall; a tumble. 2. A disastrous failure; a fiasco.
ETYMOLOGY: Perhaps from the phrase neck and crop, completely