. The Canadian field-naturalist. 448 The Canadian Field-Naturalist Vol. 106 Table 4. Monthly comparison of disturbance and response characteristics for breeding Bald Eagles in northcentral Michigan, 1990. Disturbance No Response Response Frequency Median Median Median Median Median (no. of no. per distance duration Frequency distance Frequency distance Month events) event (m) (min) {%r (m) (%r (m) March 3 - - - 33 - 67 _ April 223 500 54 800 46 300 May 326 450 62 700 38 300 June 162 200 67 350 33 100 Response frequency (%) = response sample size divided by number of eve
. The Canadian field-naturalist. 448 The Canadian Field-Naturalist Vol. 106 Table 4. Monthly comparison of disturbance and response characteristics for breeding Bald Eagles in northcentral Michigan, 1990. Disturbance No Response Response Frequency Median Median Median Median Median (no. of no. per distance duration Frequency distance Frequency distance Month events) event (m) (min) {%r (m) (%r (m) March 3 - - - 33 - 67 _ April 223 500 54 800 46 300 May 326 450 62 700 38 300 June 162 200 67 350 33 100 Response frequency (%) = response sample size divided by number of events x 100%. occurred on weekends, but in May, weekend occur- rence was 44%. During this study 60% of observed human activity occurred on weekends (N = 431, versus 283 for weekdays). Weekend activity predominated at four breeding areas and was nearly equal to weekday activity at two others. Median distance-to-distur- bance was less on weekends (300 versus 600 m, ). Weekend response frequency was 44%, and weekday, 32% (P = ). Weekend frequencies of occurrence by disturbance group were vehicle 56%, pedestrian 41%, aquatic 80%, noise 62%, and aircraft 48%. Boats, autos, ATVs, and anglers occurred more commonly on weekends, while canoes and hikers were more frequent on weekdays. Human activity near breeding Bald Eagles was recorded throughout daylight hours. However, most human activity occurred after noon (72%, N = 513), with a midday peak between approximately 1300- 1500, and secondary peaks between 0900-1100 and 1600-1900 (Figure 3). Frequency patterns varied RESPONSE FREQUENCY (%) (LINE) 100 - 90 - 80 - 70 - A 60 - /\ 50 - / ^ 40 - / 30 - / 20 - i f 10 - / 0 —ii J L.^_ DISTURBANCE FREQUENCY (N) (BARS). 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 HOUR OF DAY (X100) Figure 3. Disturbance (N) and response (%) frequency by hour for 714 events of human activity near breeding Bald Eagles in northcentral Michigan, 1990. J. Please note that these images are extracted
Size: 1572px × 1589px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorottawafi, bookcentury1900, bookdecade1910, bookyear1919
