Woodpeckers are misunderstood. Here's why they peck:
They will zero in on anything cylinrdical, thinking it's a tree, branch, or root. Their first few pecks are intended to make sound; they're listening for an echo that tells them there's a hollow space under the bark. They will then drill a series of holes, until they catch up to the bug that made the tunnel.
That's what the woodpecker is following - the gap between the outer jacket and the conductors. They'll also be fooled by dry / empty irrigation tubing.
Article 110 states that wires need to be protected from mechanical damage. IMO, this general provision trumps any general provision that mights say, for example, that SE can be used for service drops. I maintain that if woodpeckers are a problem -as evidenced by the damage to the wires - code would require additional protection for the wires. Simply using an 'approved' method isn't automatically enough to meet 110. That's my take.
