Monitoring Reports
Section II. Bird Survey
Introduction
Bird surveys conducted over many years help researchers monitor trends in bird populations. These intensive, long-term studies lend insight about different species' behavior and their preferred habitats. Changes in the environment, either natural or human induced may be reflected in changes of population or species numbers.
Surveys are conducted during various times of the year, depending on the focus of the research. Spring and Fall surveys are used to record the various migratory species that use an area as a stopover site on their journey to breeding or wintering grounds. Surveys conducted in the winter are used to monitor the resident species during the non-breeding season. Breeding bird surveys are conducted during the summer months, during the height of the breeding season. In this region, the optimum sampling period is during the month of June. The optimum time of sampling is during the early morning hours, between 4:00 and 9:00 am, a period when the birds are most active.
Survey Methods
Ten stations were selected to survey the breeding birds (Figure 1). The stations are approximately 900 feet apart, within theCoffee Creek Watershed Preserve between the railroad grade (now Rail Road) on the north and the Indiana Toll Road on the south. Six of the ten stations (1, 2, 3, 4, 9 and 10) are located in wooded portions of the corridor. The stations were selected (1) to avoid overlap in potential territories and thus avoid censusing the same birds more than once and (2) to allow sampling at each of the various habitat types present within the corridor. All individuals seen and/or heard at a station within a 5-minute sampling period were recorded, except for the survey in 1997, when 10 minute intervals per station were used.
Station Descriptions
Surveys were conducted on August 4, 1997, June 21,1998, June 27, 1999, and August 3, 2000. The average temperature ranged between 72 and 75 degrees. The range of time, average temperature, weather, number of minutes spent at each station, and the number of birds and species found each year are detailed in Table 2 and illustrated in Figure 13 under Results and Discussion. Descriptions of sampling stations and the bird species recorded at each station are presented in Appendices 33-38.
| Year | Time | Avg. Temp. | Weather | Min. per Station | # Birds (# species), per Station |
| 8/4/97 | 6:00-10:40 am | N/A | N/A | 10 min. | 98 (29) |
| 6/21/98 | 5:10-8:15 am | 75˚ F | Winds calm, sky clear/partly cloudy | 5 min. | 194 (36) |
| 6/27/99 | 6:00-8:30 am | 75 ˚ F | Winds calm, sky partly cloudy/overcast | 5 min. | 264 (38) |
| 8/3/00 | 7:30-9:40 am | 72 ˚ F | Winds moderate, sky mostly sunny | 5 min | 162 (37) |
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Table 2. Amount of time spent, weather conditions, and
number of birds found at each sampling station during the
1997, 1998, 1999, and 2000 bird sampling events.
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