What about the Jack Russell? Although they have short coats, they are agile, smart, natural hunters. They would survive in most climates because they have the ability to burrow in cold weather and the short hair would be good in hot weather. They are quick and can hide easily so they would not easily become prey to other animals.
I think a lot of the terriers would adapt well. The Silky terrier( my dog) is adaptable to hot or cold weather , is agile, has a keen sense for hunting and is very quick. My silky goes out in the woods all the time and stays for hours. He loves it! I use to worry about him getting hurt by wild animals, but after I saw him roll with a raccoon and win, I knew he was ok!!