couraging in several States for the black and 

 gray francolins, and the black-necked phea- 

 sant from Iran. The red junglefowl and the 

 Kalij pheasant have not as yet been available 

 in sufficient numbers to make adequate 

 tests. 



Pesticide-wildlife relations 



Toxicological studies and pen tests. -- 

 Toxicological studies of the effects of pesti- 

 cides on wildlife were given special attention 

 in 1961 as the quickest dependable method of 

 detecting potential hazard in the use of new 

 pesticidal chemicals. Tests of herbicidal 

 chemicals were incorporated in the toxi- 

 cological program for the first time. Five 

 hundred and sixteen tests involving more 

 than 3,700 birds and mammals were made 

 with 18 insecticides and 14 herbicides. All 

 of the herbicides tested were relatively 

 nontoxic to quail, pheasant, and ducks. 

 The birds survived for long periods when 

 fed diets containing as much as 5,000 p. p.m. 

 However, certain herbicides (amitrole, 

 dalapon, and derivatives of 2,4-D and 

 2,4,5-TP) appeared to depress reproduction 

 of ducks when fed at levels less than 25 

 percent of those producing mortality. 



Some of the newer organophosphorus in- 

 secticides are highly toxic to birds, and 

 appear to be cumulative in action. Phos- 

 phamidon, which has been suggested for 

 gypsy moth control, is much more toxic 

 than parathion, and quail will not survive 

 on diets containing 1 p. p.m. Co-Ral, dexon, 

 dimethoate, Bayer 25141, and Bayer 29493 

 also are more toxic than parathion, and 

 levels of these compounds producing death 

 of quail range from 1 to 50 p. p.m. Dibrom, 

 thimet, and thiodan have relatively low 

 orders of toxicity, and do not appear to 

 produce cumulative effects. 



Toxicity of heptachlor to woodcock was 

 measured in a special series of tests with 

 birds captured on the Louisiana wintering 

 grounds. Woodcock feed largely on earth- 

 worms and apparently will accept only 

 living food, so it was necessary to develop 

 suitable methods and time periods for 

 exposure of earthworms to the toxicant. 

 The earthworms stored toxicant in their 



tissues without obvious harnn to themselves, 

 and the woodcock showed no aversion to 

 eating poisoned worms. 



Fifty percent of the birds (6 of 12) which 

 fed on worms containing an average of 3 

 p.p.nn. of toxicant died within 34 days. Four 

 more birds had died by the 51st day, and 

 the remaining two were then killed for 

 chennical analysis. Worms collected in 

 areas treated with heptachlor often contain 

 more toxicant than the worms fed to the 

 experimental birds. 



Collections and chemical analyses of 

 woodcock were continued in an effort to 

 determine the extent of heptachlor con- 

 tamination in thewild population. Heptachlor 

 epoxide was found in a high proportion of 

 birds collected in the South and in a high 

 proportion of adults collected in the spring 

 in the North. 



Two new chemicals (kepone and its analog 

 GC-1283) which are being tested for use 

 in fire ant control were found to be con- 

 siderably less toxic to birds than is hep- 

 tachlor. Tests showed, however, that kepone 

 had a marked depressive effect upon re- 

 production of quail and pheasants. Pro- 

 longed exposure to this compound resulted 

 in loss of characteristic coloration of male 

 quail, pheasants, and mallards, and in 

 marked tissue changes in the livers and 

 gonads of pheasants. 



At the Denver Wildlife Research Center 

 one deer and nine cottontail rabbits were 

 fed diets containing varying amounts of 

 pure DDT (p,p' -isomer). This was done 

 in part to test a hypothesis explaining the 

 presence of DDD (Rothane or TDE) residues 

 found in analyzing many field samples. 

 The subsequent presence and prevalence 

 of DDD in the tissues of the rabbits and 

 deer experimentally exposed to pure pp'- 

 DDT must be explained by changes taking 

 place within the bodies of the exposed 

 animals. Since the identity of DDD was 

 established by the infrared spectrophoto- 

 meter and by an alternate paper chroma- 

 tographic technique, it remains only to 

 determine where within the animal, and 

 how, this conversion is accomplished. 

 Generally, DDT has been considered to 



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