4 
26 FISH PONDS ON FARMS. 
cool waters reproduction may be delayed until the fourth year, or 
in case the species is very poorly adapted to the temperature condi- 
tions the fish may remain small, stunted specimens throughout life 
and never reproduce. 
ENEMIES. 
There are many enemies of fish, especially of fry and fingerlings, 
against which the fish culturist must wage continual warfare. The 
heaviest losses will be from cannibalism, and these will be gauged 
by the balance of the food and fish in the pond. Some species are 
more predaceous than others. For this reason black basses, the scourge 
of restricted waters, are recommended only for large areas of the 
highest fertility. Such species as pike and pickerel should never be 
selected for culture in ponds, as they are the most piratical and 
devastating fishes inhabiting fresh waters. 
It is necessary to guard closely against the inadvertent establish- 
ment in a pond of any undesirable species of fish or animal. Turtles 
and snakes will consume large numbers of fry and fingerlings in the 
course of a season and should be barred from the waters as strictly 
as possible. Kingfishers, herons, ducks, mudhens, fish hawks, etc., 
soon locate a pond and prove most persistent poachers. Powder and 
shot is their most effective deterrent. If inroads on the stock are 
made by mink, they should be trapped in season—at a time when they 
will, at least in part, make reimbursement for their board. Musk- 
rats, while not fish destroyers, work havoc with pond embankments 
and should be exterminated. 
METHODS EMPLOYED BY THE BUREAU OF FISHERIES IN THE 
DISTRIBUTION OF FISH. 
The Bureau of Fisheries will undertake to furnish fish to indi- 
viduals for stocking public and private waters. Blanks upon which 
to submit formal application will be supplied on request. Assign- 
ments of fish are made large enough to form the nucleus for a brood 
stock for a given area of water, and are delivered at the applicant’s 
railroad station free of charge. From the information given in these 
applications the Bureau decides as to the suitability of the waters 
for the fish asked for and reserves the right to substitute other species 
if in its judgment the applicant’s selection is ill chosen or it is im- 
possible, with its limited facilities, to supply the species specified 
within a reasonable length of time. 
None of the pond fishes recommended in the foregoing pages will 
be furnished by the Bureau for stocking lakes or streams in Washing- 
ton, Oregon, California, Idaho, Nevada, or the western portions of 
Wyoming or Montana, as it is believed their introduction into such 
