The smaller escapee was easier to catch and I lifted her back. Then I called Peter who was at work, at lunch.
P thought that I could leave the ewe and she would find her own way back but I didn't think she would figure out the itinerary so we decided to cut the fence. I walked back to the garage to look for cutters and also grabbed a free-standing fencing panel. When I got back down the lake, another ewe had found her way out.
I cut the fence next to one of the posts and rolled back the fencing to create an opening. I then attached the fence panel making temporary hinges out of rope. Luckily it was a perfect fit. While chasing the sheep I noticed that they always ran along the fence never venturing far away from the others (who are all watching with great curiosity, as only sheep do). So I pushed the gate out at right angles to the fence and then using a long stick I coaxed them along the fence and they slipped neatly back into the field. Well, that was easier than expected!