Weigh in.

Weighed the hives -- with an electronic fish scale - by lifting the back end of each hive off the ground.  Most of the hives weighed 18-22kg -- but #2 (the one with 3 Farrars) weighed 28kg and hive #9 (Rosendal) weighed only 11kg.  Added a Apifonda (2,5kg) packet in all hives except #2.

It has been an exceptionally warm month of February, with temperatures often well above zero during the day, so we were worried the bees would be leaving the hives, burning up energy and eating all their reserves.