I don't believe that the majority of kangaroos are killed because they are in 'plague proportions'.
The primary reason they do damage to fences is because the fences were erected to keep cattle/sheep and horses IN and not kangaroos OUT. Kangaroos unfortunately try to jump the fences, sometimes successfully, other times not - and therefore get entangled (read hung up) quite cruelly in the barbed wire. Other times they manage to successfully untangle themselves but continue on injured.
You don't see kangaroos grazing on deer properties with properly designed fences to keep deer IN because deer leap as well and will leap over cattle/sheep/horse fences. If the farmers had bothered to think about what they were trying to keep out as well as what they were trying to keep in... they may have solved their problem in part. I won't even go into the argument of the kangaroos were here first.
And... we have kangaroos, wallabies, wombats, cattle, horses and deer on our property so I can speak from some experience. I value them all. As did my father who left one quarter of the property in its natural state so that the lyrebirds, possums (including the greater glider and the pygmy feathertailed glider) could enjoy their continued existence. He built a huge lake and that houses platypus as well.
The deer are escapees - some from long ago, and travel through the property.
