White Dorpers and Dorpers behave differently to Merino sheep. If anything they are more like goats and cattle. They are naturally curious, will investigate everything in their paddock, enjoy eating rough food, recognise an open gate, know what a poor fence looks like and are easily trained to respect fences as young sheep.
White Dorpers and Dorpers need to be lambed and weaned in secure paddocks. The lambs learn the habits of the ewes. In our own experience, we had more trouble with Poll Dorset rams pushing through fences than White Dorpers.