A recent popular magazine ran an article about how a dog saved a man from a copperhead snake. What rubbish! Yes, copperhead snakes are poisonous. Their bites are rarely fatal, especially from a smaller snake like the one in the article.
Why do I know about these much maligned snakes? I live with them in a place once called Copperhead Gulch.
A recent article in “The Missouri Conservationist” (Vol 82, issue 6, June 2021 ) about a study of these snakes confirmed what I’ve known for years. They are shy, prefer to flee and are rarely fatal.

One of my first encounters was when my half grown cat Mittens came in with her leg swollen. It was night so I made her as comfortable as I could. She was miserable with her leg triple its normal size.
In the morning the vet told me it was probably a copperhead bite. Mittens would recover. She did and lived a long life after that.
One or more of my goats get bitten every year. Copperhead snakes like moist areas like stream beds and the goats step on them.
The affected goat limps in that evening. Her leg is swollen so that her toes stick out. She lies down in a corner of the barn and moans all night.

The next morning the swelling is going down. The goat is up, still limping, but eager to go out to pasture for the day.
The vet can give a steroid shot to the cat or goat to make the swelling go down faster. It is expensive and doesn’t cut the recovery time down very much.
One year I found a hen dead in my chicken yard. The next day another one was dead. Then it stopped.
I stepped into the hen house that night to gather eggs and found I had stepped over a copperhead now coiling up just inside the door sill. We stared at each other a few tense moments. It slid quickly over the floor to go under the cement pad under the roost.

I checked carefully the next few days before entering the hen house. I saw the snake several times. Then I didn’t.
The snake still lived there hunting the mice that came out at night. I caught glimpses now and then over the three years it was there. I assume the snake had learned the chickens went to bed at night and I came when the light was on at night, so it waited.
Are many poisonous snakes dangerous? Probably. As is mentioned in “America’s Snake: The Rise and Fall of the Timber Rattlesnake”, most bites in the U.S. are because someone was showing off and threatening the snake.
In 30 years I’ve only come across one aggressive copperhead and I’ve seen dozens. Copperhead snakes are not the dangerous snakes people like to tell stories about. Given a chance they will avoid you. After all, you are far too big to eat.
Black rat snakes are a bigger problem in the hen house as discussed in “Exploring the Ozark Hills“.