Designing a new instrument that has the option of a secondary "power pack" a short distance (maybe up to a few meters) away. Environment is temperate to boreal forests. These instruments may be deployed for a fairly long time (possibly 6 months or more). Animal damage is a significant possibility; think squirrels. porcupines, and such. I am looking for a cable that might be nominally resistant to these creatures. Cable will be two conductor, maybe 16-18AWG or so. Currents are low (few mA). I realize that no cable can be totally resistant, but something that will withstand a casual assault would be helpful.
Suggestions, especially based on experience, are appreciated.