When the time came to set my little fish free in the rearing ponds, as a matter of principle I covered the ponds with herring-net, closely pegged down on the banks so that I could not even get my hand under the edge. I did not think that there were any kingfishers or herons about, and so was very surprised when one morning, on going down to feed the fish, I found a kingfisher under the net, flying up and down the pond trying to get out. By carefully introducing a landing-net under the netting over the pond, I was able to catch the intruder, and caught four more in the same way in about three weeks. Since that time I have not agreed with the people who have stated that the kingfisher is almost extinct, at least in that part of the country. I may say that there are but few streams there, and that it is not at all an apparently likely place for kingfishers. I am quite sure that wherever any one begins to rear fish there he will find that kingfishers are fairly common. The amateur will probably be also surprised at the way herons appear, if he conducts his fish-rearing operations, as he should do, in a secluded spot.
Many of the directions I gave as to the management of the fry and the rearing boxes, apply also to the fry after they have been turned out into the ponds. The doses of earth should still be given regularly, and salt may be applied also in the way I have already described. The little fish will be found to scatter over the pond or to divide again into two bodies, one at the upper and one at the lower end of the pond, as they did in the boxes. The fish culturist should try to induce these fish to come to the head of the pond as much as possible. It is a good thing to place some boards across the head of the pond to give shade and shelter to the fry. It will probably be found that if much artificial food is given to the little fish, a scum will be formed on the surface of the water. This scum is composed of grease, and should be removed, as soon as it is observed, with a gauze net.
All the time that these operations have been going on with regard to the little fish themselves, due attention should have been given to the vegetation round the ponds. The alders and willows which I before recommended to be planted round the ponds should be induced as much as possible to overhang the water. Grass and other vegetation should be allowed to grow freely round the margins, as many insects are then likely to fall into the water.