EXCLUDING BIRDS FROM RESERVOIRS AND FISHPONDS 5 
marauders. When the large fish are put out they remain in the stream only 
a short time until they are caught. In this way, losses to vermin are reduced 
to a minimum. Therefore, the really practical way to get the most for our 
money and efforts is to raise the trout in completely protected areas until 
they are big enough to be put into the streams or grown still larger in semi- 
protected ponds. 
A poultry-netting fence 3 or 4 feet high will suffice to stop the 
access of birds on the ground to a pond. The fence can be placed 
just on the edge of the pond (where, enclosing the minimum space, 
it will cost least), or it can be set back the necessary distance if 
margins have to be left for carrying on some of the management 
operations. Such a fence would be too high for even great blue 
herons to fish over, and if its upper edge is left without special sup- 
port and the posts. are pointed or tipped with an erect wire, it will 
not serve as a perch even for the smallest of the notable winged 
predators—the kingfisher. 
FicurRH 3.—A, Suggested framework to support a 3- to 4-foot poultry-netting fence and 
an overhead eross wiring for a small pond; B, wicket-shaped guard wires inserted in 
a wood strip for conv enient installation; C, posts guarded against perchers by sharpen- 
ing and by insertion of a guard wire. 
The posts of the fence can be extended upward to any practicaple 
height necessitated by operations in the pond and joined by a mar- 
ginal frame of the same material, to which the overhead wires can 
be fastened. This frame should bear a series of stiff vertical wires 
to prevent perching, or perhaps more conveniently could be over- 
laid by a wooden strip through which such wires project. The choice 
of material for this framework will depend on the size of the en- 
closure and the resultant weight and pull of the cross wires. For 
ponds 50 feet or less in length, wood will do, but for larger ones, 
and in any case for stronger and more lasting service, galvanized 
pipe of appropriate diameter or other metal supports will be best. 
Consideration also should be given in some sections to the probable 
increase in the weight of wiring as a consequence of sleet storms. 
For long spans it Will be necessary to brace the corner posts, and 
