Do you know that goats aren't afraid of rubber snakes? I bought some very realistic ones that scare guests but the goats just lay down and sleep on them. I was hoping to keep the snakes off the porch, but so far, no go.
@Sanguine One answer is "yard cats". Cats LOVE eating snakes. They will get together to gang up and kill one,and then fight each other to see who gets to eat it. I've had my shop cats kill and eat a big cottonmouth that got into my workshop,and had the house cats catch and kill a copperhead they discovered slithering down the hallway one day.
The cottonmouth was over 3 feet long and they had been trying to warn me he was in the shop for a couple of days,but I was distracted and didn't pay any attention. When I would go in there in the afternoons to give them food and water,instead of greeting me at the door,they would be up on the hood or roof of my 33 Dodge sedan. The tom would jump off,walk a couple of steps,stop and look around really carefully,and then walk a few more. Should have made me suspicious,but I was having health issues and ignored it.
Then one day I went in there to get some lumber for a house repair,and as I was sorting through the lumber stack I saw movement out of the corner of my eye,and saw over 2 feet of cottonmouth slithering behind the lumber stack. Couldn't shoot because of ricochets,and couldn't immediately grab a square point shovel,so I let it go for another day. Found the shovel and left it by the door,and went in there wearing leather boots for the next couple of days. Moved every piece of lumber the first day,but he was no longer there,so I figured he was crawled up under one of the cars. Since there was no chance of me crawling under a car to look for a cottonmouth,I left it for another day.
I think it was the 3rd or 4th day I went in there looking for the snake,and the first thing I noticed was the cats waterbowl and food bowl were overturned in the floor,and both of the shop cats were laying in the floor flat of their backs,snoozing. They didn't even wake up when I came in and closed the door. Right away I knew they were "sleeping off a snake dinner",and I had nothing to worry about.
I found out about the copperhead in the hallway when I heard the cats jumping and making noises,and went to look. I have no idea how they caught and killed that one without getting bitten,since the hallway was so narrow,but they did the job.
BTW,if you see snakes in your yard or live in an area with a lot of snakes,you need a couple of house cats,too. If they are in the yard,it is only a matter of time before they are in the house. If a mouse can get in your house,so can a snake. In fact,the snake is in there looking for mice.
Get two house cats. A snake stands a chance against one cat,but two cats will tag team him,and while one has him distracted,the other will get him from behind and bite his head off..
The will then fight each other over who gets to eat him,but ignore that. It's just "cat business" and they will work it out.