my 5 c worth:
The only way I know to catch a lose Guinea is with a net, just after dark - and you get only one chance! They tend to get calmer and got to sleep at night and they cannot see in the dark. Be careful about that: if you chase them into an obstacle, they could fly up in a panic and break their neck. They tend to panic at night because they cannot see.
It is also very important to get a net that has holes small enough so they cannot stick their head through the net ***or you could break their neck. ***
I got a fishing net at Walmart in the sports equipment department - the biggest one I could find, that is with as big a mouth opening as I could find, but with a fine mesh as the netting material - do not get netting material that has big openings! They had both kinds there when I was looking and I got the wrong one first.
Then I would make myself aware of the exact location of the Guinea before it gets dark. Usually on the branch of a tree or the roof. After dark, I would get on a ladder or just reach up with the net to slip the net over the Guinea's head and body and then pull them towards my body and with a twist of the wrist close the opening of the net and catch the Guinea in side, careful not to hurt them. The opening will be turned 90 degrees from the capture position and the net will cover/close the opening and the Guinea will dangle in the loop of the net below the opening and not able to escape.
If you miss, the Guinea is going to fly up in fright to a higher location and usually out of reach for that night.
The fact that they tend to fly up in panic when they feel attacked is something to consider also, to avoid hurting them and to anticipate an effective capture in the net.
I usually try to carry them in the net with the opening covered by the net and then carefully set them on the ground and untwist my wrist to open the opening back up and let them walk out. Some light is needed here for them to see where they are and how to get out. Sometimes I have to help get the helmet out of a net opening but I try to avoid having to reach for them because it scares them so.
Also be aware that the other Guineas in the pen are going to panic when you come in with this huge net. There needs to be enough space to somehow get in and let the capture out while the others can hide in a corner somewhere.
Not sure any of this helps.
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