Biologists at the Rose Lake Wildlife Experiment Station tested two devices designed to reduce wildlife losses during hay mowing. We ran the tests on the farm area of the station near Lansing, Michigan, from 1950 through 1955. During four of these years we tested the Ohio flushing bar (Warvel, 1949) using four-pound cast-iron sash weights suspended from cables, and during three years we used the extension of the exhaust pipe of a tractor as a flushing device. Flexible metal tubing was attached to the exhaust pipe and supported by the bar used for the Ohio flushing device. This arrangement directed the noise and blast of the unmuffled exhaust into the hay about 13 feet in front of the cutter bar and in the middle of the swath. We found both devices to be mechanically satisfactory, requiring little maintenance. Our tests had the advantage of being closely observed but the disadvantage of dealing with a small population of ring-necked pheasants. Game flushed or killed was tallied by a biologist riding on the mowing machine. We mounted a seat on the caster wheel of a John Deere No. 5 Power Mower so that the observer could get a clear view of the cutter bar and the effects of the flushing device. Because of low pheasant numbers, biologists had to observe the cutting of over 900 acres of hay in order to get approximately 100 pheasant flushes from both of the devices and the control. Spring pheasant numbers on the experiment station varied between six and eight birds per 100 acres during the study period, and hayfield losses were not a serious mortality factor. There was approximately one nest per 30 acres of hay during the 6-year period. While the low pheasant population was not ideal for the test, I feel we did flush enough pheasants to establish the relative effectiveness of the two devices under Rose Lake conditions. In the cutting of 936 acres of hay, 304 pheasant and 101 rabbit flushes were observed, and 13 adult hen and 47 juvenile pheasants and 15 rabbits were killed. We used a John Deere Model B tractor operating at between four and five miles per hour. The hay was secondand third-year alfalfa mixed with smooth brome grass (Bromus inermis). Figures given in this paper are for the first cutting only. The first cutting usually began at or just before the peak of pheasant hatching so that most of the fields were actually cut just after the hatching peak had passed. Between 15 and 20 individual hayfields were involved each year, and a total of 35 different fields were cut during the 6-year period. For the first three years we cut half the total hay acreage with the Ohio bar and half as a control. The fourth year we cut a third with the Ohio bar, a third with the exhaust, and a third as a control. For the last two years we cut half the acreage with the exhaust and half as a control. Each individual field was cut entirely by one method. We attempted to cut adjoining fields by different methods, and during the test period all fields were at some time cut by each method. Our tests failed to show that either the Ohio bar or use of the exhaust blast reduced hayfield mortalities (Table 1). We were disappointed with the results, since investigators in other states have reported greatly reduced pheasant losses when using the Ohio-type flushing bar (Wisconsin-Bell, 1954; Iowa-Boehnke, 1954, and Klonglan, 1955; North Dakota-Fisher, 1954; Ohio-Warvel, 1949, and Swagler, 1951). The failure of the exhaust blast was not surprising, in view of the experimental findings of Stewart and Dustman (1955) regarding the response of incubating pheasants' auditory stimuli.
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Oct 1, 1996
Y Yavin 
Open Access