
Practically all the dead fish (Fundulus) measured less than 3 inches, while 
the surviving ones (also Fundulus) ranged from less than 2 inches to slightly 
more than inches long. 
In the 0.2 area mortality was very light. Only 3 dead fish were 
found in the 225-foot channel section between barriers the day after 
spraying and none additional were noted thereafter. live fish were not 
counted since a hole that developed under the lower screen barrier on the 
fourth day after treatment made possible the escape of some. 
Caged Fish 
An attempt was made to appraise mortality by means of cages 
containing known numbers of fish. The cages measured 2 feet on each side 
and were covered with 1/lj-inch hardware cloth. They were placed in ponds 
or creek channels prior to spraying. The procedure, as applied, proved 
unsatisfactory and did not give usable results. It appears probable, 
however, that with slight changes, the equipment and method may prove 
useful in future investigations. Experience in these preliminary studies 
indicated need for greater care in handling captive fish and showed the 
importance of having specimens sufficiently large to avoid confusion with 
smal] killifish able to enter through the wire mesh. Although the effects 
of spraying on fish populations were not determined satisfactorily by this 
method, there was evidence that killifish of the genus Cyprinodon survive 
DUI treatment better than do species of Fundulus. 
11 
