PIKES AND PIKE PERCH #4 
and used repeatedly for two or three days, the pike perch can be 
used but once. When held for several days, especially late in the 
season, the milt comes from the fish thickened, as if taken from a 
dead fish, and is far from being at its best. However, this is true 
to a great extent with the fish taken fresh from the nets late in the 
season. Females that do not “ripen” within two or three days 
are likely not to furnish eggs at all, and if held even two or three 
days late in the season may yield eggs that will not hatch. 
At the Put in Bay (Ohio) station pike perch are obtained in the 
same manner as whitefish—from the pound nets of the fishermen. 
They are sometimes taken directly into the tanks on board the 
steamer from the pound when it is raised, but more often are dipped 
into supplemental nets by an employee of the bureau, who accom- 
panies the fishermen when the pound is lifted, and are held until 
they can be picked up at leisure by the steamer. This permits the 
gathering of fish from many nets, while if they were taken directly 
from the pound only one lifting boat could be followed at a time 
and comparatively few fish collected. The supplemental nets are 
placed at each.pound net where fish are expected. They are 3 feet 
in diameter and 7 feet in depth, and are held open at top and bottom 
by rings of half-inch iron, the bottoms being provided with pucker- 
ing strings to close them. The top ring is fastened to the outhaul 
stake and rim line of the pound, the lower one hanging free and 
acting as a weight to hold the end in place and also serving to keep 
the net open so that the fish will have plenty of room and not be 
scaled by chafing against the meshes. When thus located, the sup- 
plemental net is in a convenient position for receiving the fish when 
the pound is lifted. Rowboats transfer the fish in tubs to the 
steamer, where they are placed in tanks and transported to the pens. 
There they are counted and assorted as to ripeness. 
The pens or live boxes used in the pike-perch work are the same as 
those used for whitefish. Stationary live boxes, supported by piling 
have been used, but as the water at Put in Bay becomes too warm for 
this the boxes are now made so that they can be towed like a raft into 
open waters, where the current is more vigorous and the temperature 
more uniform. Another advantage gained by this method is that an 
equal depth of water is maintained in the live boxes, the rise and fall 
in this section varying from 4 to 5 feet in a single day, according to 
the direction and velocity of the wind and the atmospheric pressure. 
The boxes are 16 feet long, 8 feet wide, and 8 feet deep, divided into 
two equal compartments 8 feet square, provided with false bottoms 
controlled by standards running in guides at the ends. The stand- 
ards are pierced by inch holes at intervals of 6 inches, so that the 
false bottoms may be held at any desired place. 
The pens, in groups of five, are fastened, end on, between booms, 
and the whole thus forms a raft. The booms are made of 4 by 8 
hemlock joists, 2 feet apart on the outside, trussed at frequent inter- 
vals by diagonal cross braces and ties, on top of which are placed two 
tiers of 1-foot wide hemlock planks, thus making the booms, when 
completed, 52 feet long, 2 feet wide, and 1 foot deep, and quite strong 
and rigid, capable of withstanding seas of considerable violence. At 
38258°—27——2 
