Ue 



1958 



Scott: Wildlife Research 



195 



in greater detail in a report, now in 

 preparation, on sex ratios in doves. 



The effort to appraise mortality among 

 mourning doves included study of their 

 parasites and diseases (Kossack (Sc Han- 

 son 1954; Levine 1954; Hanson, Levine, 

 Kossack, Kantor, & Stannard 1957). The 

 paper by Han:on et al. describes the 

 ectoparasites of doves and the arthropod 

 fauna of their nests and summarizes the 

 results of a 7-year study of the incidence 

 of blood parasites in relation to ages of 

 the doves and to regions of the state. 



The relation of age and the stages of 

 wing molt to body weight, body fat, and 

 migration habits was studied (Hanson & 

 Kossack \951 b) . In contrast to interpre- 

 tations of fat deposition in passerines, the 

 analysis of data on fat deposition in 

 mourning doves showed no consistent re- 

 lationship to migratory habits, but instead 

 proved to be related to the energ>' de- 

 mands of the molt, regional farming prac- 

 tices, soil fertility, and food habits. Doves 

 that had fed almost exclusively on corn 

 in good soil areas had formed relatively 

 heavy amounts of fat ; most of those taken 

 on poor, sandy soil where they fed largely 

 on seeds of wild plants had formed little 

 or no fat. 



After 10 years of study there is still 

 no evidence that dove populations in Illi- 

 nois are controlled by hunting. Popula- 

 tion declines which have taken place are 

 generally traceable to habitat destruction, 

 disease, and adverse weather. 



Mammals 



To the wildlife historian the apparent 

 lack of interest in mammals by early re- 

 searchers of the Natural History Survey 

 and its predecessors constitutes something 

 of an enigma. Almost half a century 

 slipped away before Forbes, upon receiv- 

 ing a letter from C. A. Rowe of Jackson- 

 ville in April of 1907 reporting the de- 

 struction of seed corn by moles and en- 

 closing the stomach contents of a mole 

 containing about 65 per cent corn, was 

 stimulated to authorize research on a 

 problem in economic mammalogy (West 

 1910:14). The resulting studies (Wood 

 1910^; West 1910) provided the f^rst evi- 

 dence that moles included corn, or any 

 substantial amount of plant food, for 

 that matter, in their diet. 



Fur-Bearing Mammals. — Forbes 

 (1912//) included fur-bearing mammals 

 among the animal resources of Illinois, 

 but a program of consequence did not 

 get under way until the 1930's, when 

 evaluations of fur resources were under- 

 taken. 



Neither technical nor popular interest was 

 great enough to focus further attention of 

 the state's research agencies on furbearers 

 until, in 1930, David H. Thompson, E. C. 

 Driver, and D. I. Rasmussen of the Illinois 

 Natural History Survey staff borrowed trap- 

 pers" reports . . . from the Illinois State De- 

 partment of Conservation, to which law 

 provided that each licensed trapper report 

 his catch monthly during the trapping season 

 (Mohr 1943rt:505). 



Brown ^ Yeager (1943:437) stated 

 that some of the figures derived by Driver 

 and Rasmussen were published in the 

 Blue Book of the State of Illinois (Frison 

 1931, 1933). 



Following a limited survey of helminth 

 parasites in fur-bearing animals collected 

 during the hunting seasons of 1935—36 

 and 1936-37, Leigh (1940:191) stated 

 that "A study of the literature offers lit- 

 tle information on pathogenicity of the 

 parasites found in the hosts studied." 

 This shortcoming in our knowledge con- 

 tinues to prevail. 



The desire to obtain a reasonably re- 

 liable evaluation of the fur resource in 

 Illinois eventually resulted in two im- 

 pressive reports (Brown & Yeager 1943; 

 Mohr 1943^/). Brown & Yeager (1943) 

 based their evaluation on an intensive 

 oral survey covering the 1938-39 and 

 1939-40 trapping seasons, and Mohr 

 (1943rt) made an analysis of fur-taker re- 

 ports beginning with the 1929-30 trap- 

 ping season and ending with that of 

 1939_40, excepting the 1931-32, 1932- 

 33, and 1933-34 seasons. The results 

 obtained by the two methods were rela- 

 tively similar. The average value of the 

 annual fur catch was estimated to have 

 been a little over $1,000,000, about 80 

 per cent of which represented returns for 

 muskrats and minks. To aid in investiga- 

 tion of fur-bearing animals. Yeager 

 (1941fl) assembled a bibli()graph\- of over 

 2,600 references on North American fur 

 animals. 



Some valuable contributions on the 

 relationship of muskrat populations to 



