Not Too Hot To Handle 61 



fers trout or bass, or catfish, perch, or suckers, he takes his 

 sport seriously and is much concerned about the finny popu- 

 lation of our lakes and streams. 



So, when water areas are sprayed to control the mos- 

 quito, or when forest areas are sprayed to control the numer- 

 ous insect enemies of our forest trees, the fisherman is un- 

 derstandably concerned about the effea of DDT upon his 

 favorite sport. 



The toxicity of DDT to fish has not been studied as 

 thoroughly as has been the toxicity toward warm-blooded 

 animals, but experiments that have been carried out indicate 

 that fish and cold-blooded animals, such as frogs, snakes, 

 salamanders, and crayfish, are killed by quantities of DDT 

 which wouldn't even make a warm-blooded animal sick. 



From a practical point of view, this means that waters 

 containing fish should not be treated with too high doses of 

 DDT. One-half to one pound of DDT per acre of pond or 

 stream will kill lots of fish, and will destroy an even higher 

 percentage of the aquatic insects upon which the fish feed. 

 Therefore, it is a good idea to keep DDT out of the home of 

 the fish, except where it is applied for mosquito control and 

 the concentrati on is kept very low. 



It s a Bird! 



Birds, unlike fish, can tolerate appreciable amounts of 

 DDT without turning up their toes. In faa, birds react to- 

 ward DDT in about the same manner as rats, rabbits, sheep, 

 and dogs. A toxic dose of DDT is about the same per unit 

 of weight for animals with feathers as it is for animals with 

 fur. 



When large forest areas were first treated with DDT for 



