sheep farmers no more

Innocent looking sheep or highly skilled escape artists? Our two Perendale ewes, ZsaZsa and Pamela, and their lambs, Agnes and Arni, have eaten the grass in the sheep paddock down to the roots. And "we will NOT eat hay!" So we tried adding extra fencing wire to a second paddock, with ample grass. No go. They just did the limbo under the bottom wire (10cm from the ground) and stood in the middle of Falls Road playing chicken with milk tankers and other passing cars. what to do?