LRGV Nocturnal Bird Migration Study
Weekly Dickcissel (DICK) night flight call (nfc) totals automatically detected by Nighthawk software. Call monitoring in in 2024 occurred from 9pm-5am. In 2025 it occurred from half an hour after sunset to 90 minutes before sunrise. So, 2024 data involve a consistent 8-hour sample of the night and 2025 involves a consistent time frame relative to sunset and sunrise. For example on July 15, 8 hours and 23 minutes of the night was sampled; on August 15, 8 hours and 58 minutes of the night was sampled; on September 15, 9 hours and 42 minutes of the night was sampled; and on October 15 the nightly sample is 10 hours and 28 minutes. So, 2025 sampled a larger duration of night than 2024 and it increased as the season progressed. Therefore more DICK calls per night/week was likely in 2025. At the end of the season, the data will be converted to percent of total calls per week, which will help provide a better comparison between years.
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