We have terrier mixes that look like tall, curly coated JRT. Our dog also used to jump or climb fences to go on little adventures, she killed chickens..
It's been wonderful since we got a remote training collar. It has a beep setting and ten levels of shock correction. After a couple of days of one on one training, it's been great. Before she used to charge the pen all the time, now she gives it a very big berth. Once a worker left the gate open, she ambled out, and I beeped the collar. She returned and sat at the main closed gate and waited for me to let her back in. Terriers are difficult dogs to train, it's a big power struggle and pain doesn't work for them when it's coming from your hands. Now she associates her behaviour with the beeping/shock and if beeped she runs home immediately.
We were considering rehoming her, it was so bad. Now she's been angelic for months.