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RESULTS (in progress)

During mid-April through mid-June of 2016-2018, more than 5000 station-hours of nocturnal audio recordings were collected. Eight monitoring stations operated in spring 2016, four in spring 2017, and two in spring 2018. Table 1 indicates the span of monitoring at each station/year with the number of nights of data actually collected -- some nights were missed due to equipment malfunction.

 

71,739 high frequency bird calls (5-10 kHz) were extracted with the Tseep software, most from migrating warblers & sparrows. 20,000+ mid-frequency bird calls (2-5 kHz) were extracted with the Thrush software, the majority from migrating Catharus thrushes. Due to substantial & variable background noise in the mid-frequency range (primarily frog song), quantitative comparison of bird calling in this range was limited to certain species. The 5-10 kHz high frequency range had minimal, and relatively uniform, background noise and this enabled quantitative comparison of bird calls (primarily warblers & sparrows). These data are presented graphically here by date, in station comparison, and by distance from Lake Ontario.

 

The primary sources causing background noise differences in the high frequency band were wind and surf noise. Inter- and intrastation background sound level measurements are linked here and on the forthcoming station comparison pages.

 

Stations 2 & 3 had continuous nightly records for the period May 4 - May 28 in both 2016 and 2017, and station 3 had a continuous nightly record for that period in 2018. Comparison of the nightly warbler and sparrow calling at these stations for the three years is shown here: 2016-2018 warbler & sparrow comparative calling record.

 

So far in the study, 22 species listed in New York as Threatened (3), Special Concern (5), or Species of Greatest Conservation Need (SGCN) have been detected. A number of other species detected are quite rare in the region of the study (i.e., Barn Owl, LeConte's Sparrow). Audio evidence, data, and discussion about these listed and rare species are presented at the following link: Rare Species. Species & quantitative information for calls detected in the high frequency band in spring 2016 (primarily warblers & sparrows), are available in a "Vesper" spectrograph & audio archive (~28,000 calls) searchable by station, date and species. Similar 2017 & 2018 data are still in analysis.

 

The all-night audio recordings (wav files) from this study (2016-2018; ~1.5 terabytes) are available by contacting Bill Evans (ear2sky at oldbird dot org) - a labor, media, and archival fee is involved.