PRACTICAL USE OF FISH 403 
In the southern United States for many years intelligent persons here and 
there have introduced fish into water tanks for this purpose. Mr. E. A. Schwarz 
found in 1895 that at Beeville, Texas, a little fish was used for this purpose. 
The fish was called a perch, but its exact specific character is not known. Prior 
to 1900, Mr. F. W. Urich, of Trinidad, wrote the Bureau of Entomology that 
there is a little cyprinoid, common in that Island, which answers admirably 
for the purpose. In a letter to the Bureau of Entomology Mr. J. B. Fort, of 
Athens, Georgia, writes that about 1854 his father, Dr. Tomlinson Fort, living 
at Milledgeville, Georgia, found that mosquitoes were breeding extensively in a 
cistern owned by certain livery-stable keepers. They refused to use oil upon 
their cistern, and Mr. Fort was instructed by his father to catch some small fish 
from a creek nearby and place them in the cistern. About a dozen or more 
small fish were so placed and in a day or so all of the larvee were destroyed. This 
instance is mentioned as indicating the early use of fish on a small scale in 
cisterns. 
In “ Mosquitoes ” (1901), Howard recommended the practical use of stickle- 
backs, top minnows (Gambusia affinis and Fundulus notatus) and the common 
sunfish or pumpkinseed, and these fish, especially the top minnows and the sun- 
fish, were used with success in a number of instances in small ponds. An in- 
stance has been described in a letter to the Bureau of Entomology by C. T. 
Anderson, of Anderson, Washington County, Florida, who wrote that he had a 
spring on his place that swarmed with mosquito larve in the summer time. He 
got about a dozen top minnows and put them into the spring without telling the 
rest of the family. In a day or two a member of the family remarked that there 
were no wrigglers in the water. Mr. Anderson verified the observation, and 
after many months was able to state that no mosquito larve had been seen since. 
The common goldfish proves to be an excellent mosquito feeder and during 
the summer of 1901 Mr. J. Kotinsky, of the Bureau of Entomology, conducted 
a series of laboratory experiments with goldfish in an aquarium. He found they 
were voracious feeders on mosquito eggs, preferring them to larve. He further 
noticed that the fish, after taking several larve into the mouth, would eject 
some of them. Further, he found that in a large jar containing four goldfish and 
many hundreds of mosquito larve, a few of the larve succeeded in transforming 
and emerging as adult mosquitoes. The food supply was evidently in excess of 
the capacity of the fish. 
At an earlier date than this Mr. H. W. Henshaw, of the Biological Survey of 
the United States Department of Agriculture, was staying at Fruitville, near 
Oakland, California. The house was badly infested with mosquitoes. He found 
the source of supply to be a lily pond about 7 x 12 feet in size and fully 3 feet 
deep, which was fairly swarming with larve. He got a half dozen goldfish from 
San Francisco and put them in the pond. The following day they were so badly 
bloated they could hardly swim, and in a few days there was not a single larva 
left. The fish bred in the pond and from the time of their introduction there 
was a very marked decrease in the number of mosquitoes in that locality. 
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