I was tightening my chain yesterday. When i started to loosen the bolts on the axle carrier the rear end started to leak a light brown fluid where the carrier clamps down on the axle. Should I be concerned about this?

 

There should be nothing but grease in there.....sounds like you got a lot of water contaminating the axle housing, I would remove the axle and clean out the housing, check the bearings for roughness or corrosion, then pack it all back together with Marine grade wheel bearing grease, it wont mix with water like some standard greases will. there should be a small bolt on top you can hold a grease gun on and pump it full of grease when you have it clean and reassembled.