I am looking for a battery powered sound monitor for a coop. All the baby monitors we can find are plug in or are rechargeable but only have 15 hours or less charge time. Our dog barks when critters come in the yard but he does it for anything including deer. I want to hear when the chickens get scared so I can get out there in time. We have fencing all over the run but a weasel got in and killed meat birds and the next week a possum chewed through 2 layers of welded wire fence and Killed my wife's favorite Americauna hen.