Tire him out really really well before you put him outside. I mean get a dog leash attatchment for your bike (like "The Springer" or "exPETdition) and take them both on a 3-5 mile run - not trot - RUN. It should take less than 45 minutes and he will be tired for the rest of the day. No energy = no jumping the fence.

Don't let their size fool you - I have 2 pitbulls and a miniature poodle. All 3 run attatched to the bike (all 3 at the same time) The poodle has the most energy and can run farther and faster than the pits any day because he is so little. Small dogs need more exercise than most people realize. More than big or medium sized dogs. Yours look like Pugs or French Bulldogs - perfectly capable of keeping up with the bike going 8mph or so for 3-5 miles. That should be plenty to keep them tired enough to stay in your yard.

Plus.. it's really fun to run the dogs with your bike. They love it and take to it immediately. No learning curve as dogs naturally love to run as a pack. If they get distracted easily by squirrels or birds or other dogs, just pedal faster. They can't do 2 things at once - so if they start to chase after something pedal faster and they'll have no choice but to turn their attention back to you and keeping up with the bike.

Hope this helps.

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