Vo 1. 17, No. 11 
Page 2 
Beyond the initial problem of developing a random sample of hunters, there 
are two sources of bias in mail surveys: ( 1 ) response bias-hunters who'in 
correctly report their take and trips, and ( 2 ) nonresponse bias —di fferences 
in hunting activity between those who respond and those who do not respond. A 
serious effort has not yet been made to define the extent of either type of bias 
in estimates of the squirrel harvest. The present estimate may be inflated as 
much as 500,000 squirrels or more. Y C d as 
^ ■ P° nses °± fliilie Chickens to Habitat Manipulation r. L . westemeier, 
D. R. Vance 
As of 1 November 1974, 17 acquisitions totaling 1,460 acres (1,000 in 
460 'c Mari ° n Count y) are beip 9 managed for prairie chickens by 
the Natural History Survey. Additional land to complete the goal of 1,500 acres 
!" e ? ch c °^ nt y is . not presently available for purchase-at least not in suitable 
locations for prairie ch i ckens—except for one tract of 100 acres in Marion 
County. The asking price for the 100-acre tract is $800 per acre. The Prairie 
Grouse Committee of The Nature Conservancy is now negotiating with the owner, in 
accordance with our recommendation to purchase this property. Although $800 
per acre may seem high, a few tracts of farmland comparable to much of the 
present sanctuary land (purchased for $225 and $525 per acre) have recently sold 
innlTniff-' ?? ? 6r m u nearb V communities. Thus, it has become increas- 
ngly difficult to add to the sanctuary systems and perhaps impossible to 
achieve the goal of 1,500 acres in each county if we are limited to acquiring 
land by purchase. ^ a 
Additional land for prairie chicken management may become restricted to 
such areas as that to be used for the electrical power generating complex now 
frfps| COn n trUCt ' 0 n r' n u JaS ? er C0unty by Central Illinois Public Service Company 
(CIPS). Because of the sizable acreage of prairie farmland involved and the 
n^entL r ?T' ty “ ^ ?° 9 ? ta flock ’ th 15 area a PP aa rs to have considerable 
u P ra ! ne chlcken management-provided a cooperative program can be 
SnitahleV^ lm P ,e " ,en ^ ed - The font units on the CIPS area that are potentially 
presen sInr f Pra ' rie ch1cke " s , tota1 ab °ut 1,000 acres and thus could double the 
p s nt sanctuary acreage of 1,000 in Jasper County. CIPS officials were 
?o r n t ^ W,tha 1 Pre,lmlnary P r °P° sal for Prairie chicken management in July 
y/4 and have taken our proposal under advisement. 
