What a Merino flock actually needs from a fence
Merinos are a tightly flocking wool breed, and that temperament shapes the fence. A single loose dog can bunch the whole flock into a corner, so the barrier has to hold both an outside predator pushing in and frightened sheep piling against it from inside. Woven-wire field fencing is the starting point: a continuous mesh a coyote cannot walk through, tall enough that a dog cannot clear it easily, and rigid enough that it does not sag into a ladder when sheep lean and rub their dense fleeces along it.
Smooth high-tensile strands alone are a poor fit here. A predator can part them, a lamb can step between them, and a wool-heavy ewe pushing through may not feel enough to back off until she is tangled.
Mesh size, height, and the electric offset
Choose woven wire with smaller openings near the ground that graduate upward. Lambs are the sizing test: if a lamb can get its head through an opening, its shoulders may follow, and a stuck lamb is exactly the commotion that draws predators. The bottom of the fence should sit snug to the ground line, following dips rather than bridging over them, because coyotes and dogs work low and will dig where they find a shadow of a gap.
An offset electric strand on the outside of the posts, set out from the mesh at roughly predator nose height, changes the encounter. The animal investigating the fence meets the strand first, before it has a paw on the wire or a nose under it. Keep vegetation cleared off that strand — long wet grass leaning against it drains its effect and hides the very gaps you need to see.
Gates, corners, and the night pen
Most Merino losses through fencing happen at the weak furniture, not the straight runs. Gates should be mesh-filled rather than barred, hung so the gap underneath is no wider than the gap a lamb could use, and latched with something a clever dog cannot nudge and a hurried person cannot leave half-closed. Corners need proper bracing: a flock surging into a slack corner can bow posts outward and open a crawl space in a single night.
If predator pressure is heavy where you live, the strongest addition is a smaller, very tight night pen near the barn where the flock is brought in the evening. Lambing ewes especially belong in that secure core, since a ewe separated to lamb at the far end of a big pasture is the most vulnerable animal on the place.
Keeping the fence honest over a season
Fencing is not finished when it is built. Wool sheep rub, and rubbing works staples loose over months; ground shifts after rain; a fallen branch can press a whole section down and become a bridge. Walk the perimeter looking specifically at the bottom wire, the gate bottoms, and any place where washouts have scored a channel under the mesh. Repair a dig attempt the same day you find it and fill and pack it, because a predator that has started a hole will return to that exact spot.
Bring wounded or badly frightened sheep to a veterinarian promptly — bite wounds on a wool-covered animal can hide under the fleece and be far deeper than they look from outside.
Everyone who checks this flock should be looking at the same notes on fence repairs, lambing pens, and weak corners, and KinsLe Family Sharing keeps that shared picture current for the whole family.