The pilot reported that he was landing the wheel ski-equipped airplane on a remote snow-covered lake, shortly after touchdown he said the nose of the airplane began to yaw to the right. As the airplane was about 90° into the right turn the pilot heard a loud bang behind and to his right. Postaccident examination of the airplane revealed that the right main landing gear axle had sheared off the gear leg and that the forward right bungee and cabled became disconnected which allowed the ski to impact the top of the right wing which resulted in substantial damage to the wing and fuselage. The pilot said he found a wind hardened snow berm that he believed the right ski impacted on landing which caused the right axle bolts to shear from the gear leg. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.