You are right both about 14 being a good number, as well as their pecks being hard!
Today I had a bit of an adventure. I was planning to let a few guineas out today to explore a little. I had the pen open for a good while while I worked on some things in the run and the coop. It's too windy and a bit rainy out to paint unfortunately but I still had some other things on my to-do list I wanted to tackle. I also had both my dogs out, but I had my training collar on the one that killed the chick, with the remote around my neck. First all the chicks came out. The dog was laying in the grass about 6 feet from the opening to the run, and he was mindful to not even look at them...until one wandered off by itself. He got up, and if I didn't know any better I would think he was just curious, but you could see the tension in his muscles and his shoulders were low so as he approached and got within maybe 3 feet, I hit the button and he backed off. I went back to doing what I was doing, and after about 30 minutes a guinea finally wandered out, followed by another. I wanted three out so I kept waiting. A moment later all 14 were out. Well, dang.
I was standing there watching them all, thinking how small a flock of 14 looks when outside of walls or fencing, when it happened. Nope, it didn't have anything to do with the dog, who was tight by my side. The random screaming panic of a flock of guineas happened, and as always it was for no apparent reason. Generally they do this right before heading to bed each night, but here it was 12:30 in the afternoon. Birds started running all over the place and some of them took flight, one into a tree and six up onto the roof of the coop. Three ran into the coop and I closed the gate. The screaming continued and after about five minutes of running up and down the outside of the run, five more (including the one that had flown into the tree) approached the gate and I opened it up and let it in. Now I just had to deal with the 6 on the roof, which is about 11 feet up in the air. They were still screaming, and sliding around since its a metal roof, and I looked over to the field that borders my property and could see that some hawks were coming over to investigate the ruckus. My mind started spinning and I looked around to see if I had anything that I could use to stop a hawk at least 7 feet over my head if it decided to try to snatch one of the birds. I was at a loss, but luckily the hawk that was closest decided he didn't want anything do with the funny looking screaming velociraptors and headed back in the other direction.
Now what? I though. I went and got the bag of mealworms and showed them a handful, calling "pig pig pig!" like I always do when I greet or treat them. I walked into the run and left the gate open (the other guineas were making a fuss in the coop, and the chickens were huddled in a corner under the coop like they were in a war zone) and started tossing mealworms down and calling to the guineas. One by one I saw them fly down and come toward my voice. A few moments later I had them all in the pen and shut the gate quick. Phew! Hopefully they had enough adventure for the day and are content in the coop and run. I'm debating whether I want to let a few (only three REALLY) out again tomorrow. If nothing else, its good for working on the dog's behavior.
On a side note, some people think e-collars are cruel, and I'm sure at some point in my former life I would have agreed. Actually, I still do, when they are used by people who use them improperly. They go out, get a collar, slap in on the dog, and crank up the remote to yelp level. The dog does something they don't like and they start mashing the button. Wrong. Training comes first, collar comes second. ALWAYS teach right and wrong first, before you even think of using a remote correction device. I've spent the past two weeks with the dog out at the pen. He gets reward and praise for sitting or laying calmly, essentially ignoring the birds. He gets reprimanded for trying to approach the birds or becoming overly interested or predatory/obsessed. Now, the collar is on him so that I don't have to be right beside him but can give a brief yet immediate feedback and correction to his behavior. It's easy for him to behave when I am right by his side, but he needs to know that the expectation continues even if I am yards away or out of sight. I trust him fully with my goose, but these birds are flighty, animated, and small, which makes them a lot more tempting.