Vo 1. 18, No. 8 
Page 4 
Eco logy and Management of Souirrels . 
-— s - 3 - C. M. Nixon, 
S. P. Havera 
In the previous monthly newsletter (MWRL 18(7):2-3), the effects of supple- 
menta fee d, ng dunng wmter on squirrel populations were discussed. Some other 
results from the study are mentioned in this report. 
Allsquirrels trapped were examined f or sarcoptic mange (Sarcoptes scabies 
a possible indication of an inadequate diet. In December, 3 of 23 s'quTrre7s"on 
Area A (experimental) and 1 of 14 on Area B (control) had mange—no significant 
difference. However, in April, on the control area, there was a significant 
caught 56 1 tbe "umber of animals with mange. Of the 20 animals 
__J? 5 ° P ercen t) had mange and 2 were severe cases. In contrast, on the 
severe'cases'' Thts'd f f 6ed ^ ? ° Ut 34 (21 p6rcent ) had manqe a " d 2 w^re 
severe cases. This difference in the frequency of mange occurrence in Aon! 
between the two areas approached the 5 percent level of significance! ,? 
mannp rS 1 She,,ed corn may have had some effect on the occurrence of 
mange on the experimental area. Nineteen ( 9 1 percent) of the 21 squirrels with 
mange, December and April counts combined, were fox squirrels. 
females n f t n l "ml ee ? in9 * 3 Squirrel Population by enabling the mature 
heat and hrPPH n J a ' n 3 ^ f ' c1ent1y good physical condition so that they enter 
np I ! d 5 ! d dunn9 * h e w,nter - Eighteen mature females were caught in 
December and only one (on Area A) had a fall litter. However, in April the 
majority of mature females on both the control and the experimenta/areas were 
nursing young or were pregnant. On the experimental area? seven of nine (78 
percent) mature female fox squirrels were lactating and awther captured female 
a gray squirrel, was pregnant. On the control area, four of the six (67 percent) 
"; re f " e fo * “ptur.d were I ac tat i ng'and one was in heitf loth ^ 
J." 9ray S 8 U1 rreIs captured on Area 8 were lactating. It appears that 
the abundant mast supply the previous fall and the relatively mild winter was 
favorable to squirrel reproduction. 
.. SqU1rre1s haying access to a permanent source of corn during the winter 
months may maintain a relatively stable body weight throughout the winter. 
Although supplemental corn does not supply a perfect nutritional balance, it 
hould provide a ready and stable source of caloric intake in a relatively short 
time. Squirrels were weighed to the nearest 0.1 gram on their first capture 
a?el n and e bet ber ^ Apn ’ T ° n both areas to note “eight differences on the same 
, between areas. Theoretically, the squirrels on the experimental area 
bod? weigh? S A P T° P °. rt,onan y ,ess wei 9 ht and should have had a higher average 
body weight in April than squirrels on the control area. 9 
classes" ^hp^i 9 ^ ana,yS i^ the sorrels were broken down into sex- and age. 
male J? S ? X ” ^ age ' C,aSS for notin 9 weight variation is the adult 
male class because the weights of adult males are not biased by growth as in 
younger age-classes or by pregnancy and lactation as in the adult female age- 
