Usually there are more cocks than hens in a given lot of squabs and it is easier to give a hen which lays infertile eggs a new mate and sell the cock without experimenting further.
Barren hens and impotent cocks are not common in well bred birds, and very little trouble may be anticipated from such causes.
When one of a pair of squabs dies, the chances are about nine out of ten that the female of the pair dies. This is because she is two days younger than her brother and has less chance to get a start. Thus it happens that every loft produces more cocks than hens, a circumstance which has led some of the hucksters who sell pigeons as squab-raisers to send out lots of birds in which there were many more cocks than hens. This is why we have insisted that the buyer should buy from a reliable breeder and buy mated pairs.
In a loft containing fifty young cocks and fifty young hens it almost always happens that the matings are not all made up, as some birds refuse to mate with certain other ones, and there may be a few birds which have not mated. In this case the odd birds may be put among other young birds and so find mates that suit them.
In catching pairs at the time they are being recorded, or when they are to be sold as breeders, two people should do the work. A catching net, which is a netted bag the mouth of which is fastened to a hoop with a long handle, is used. The pigeon breeder soon gets so expert that he can trap a pigeon in such net without fail and without disturbing the other birds in the loft.
When a couple of pigeons is found driving, the one who does the catching traps one of them with the net while his helper keeps watch on the other one of the pair. The captured pigeon is examined and its band number put on the record. Then the helper takes the net and catches the one he has been watching and the band number is taken, always remembering that a bird with a band on the right leg is a cock and one with a band on the left is a hen.
If the method here recommended is followed, the pigeon-keeper will be able to know just what each pair of birds is doing and keep a pedigree of every bird in his flock by a simple method of bookkeeping as follows:
When the squabs that are to be kept as breeders are being banded the band numbers of the parent birds should be taken and set down in this way:
| Squab numbers | Parent numbers |
| Cock 111 | 84-67 |
| Hen 112 | 84-67 |
In making this record the number under the head "Parent numbers" is always set down in the same way, the name of the father first and the mother next.