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'. • • <br />additional 7 boxes were placed in the area during 1988 bringing <br />the total boxes to 101 available for the beginning of the 1989 <br />nesting season. <br />North Dakota <br />Two treatment areas had applications of carbaryl bait for <br />the control of grasshoppers; the largest block was 5098 acres and <br />the smaller 1807 acres. No nest boxes were near these block <br />applications; therefore no comparisons can be made between <br />nesting birds in treated and untreated areas. The information <br />presented for Restrels will be the collective data on breeding <br />success. All 100 nest boxes placed in the Demonstration Area <br />during 1987 were available for avian species at the beginning of <br />the 1988 nesting season. The majority of occupied boxes were <br />utilized by Restrels and secondly by Mountain Bluebird (Table 1); <br />twenty-eight of the boxes were not used by any species. All 35 <br />Kestrel nests were started in unoccupied boxes. Thirty-six <br />additional nest boxes were placed in this Demonstration Area in <br />1988 for a total of 136 boxes ready for the 1989 nesting season. <br />3. Results <br />Since no comparison could be made between a treated and <br />untreated area for nesting birds, nesting success by areas is <br />presented as baseline for each. Comparisons between areas are <br />indicated. Initiation of Kestrel egg laying was also determined <br />for the 4 study areas. Chick weights are presented for all <br />areas. Visual estimation of food remains are presented for Idaho <br />and North Dakota also. <br />Colorado - Front Rance <br />r Initiation of egg laying by American Kestrel was earliest on <br />the Front Range compared to the other 3 locations and peaked in <br />the first half of May as compared to later in May for the other <br />I sites (Table 3). Eighty-eight percent of the Kestrel nests <br />successfully hatched at least one egg (Table 4) and had a mean of <br />2.9 young fledged per nest attempt. This rate of success is <br />1 sufficient to maintain a stable population of Kestrels according <br />to Henny (1972) who stated that a mean of 2.88 young fledged per <br />nest was needed. A total of 60 Restrels was banded; adults <br />totaled 12 birds (11 females and 1 male) and the remaining 48 (20 <br />females and 28 males) were young produced in the nest boxes. <br />Colorado - Dinosaur National Monument (DNlL1 <br />Kestrel egg laying commenced for this area similarly to <br />Idaho and North Dakota with the peak of nests having late May <br />