Dec. 20, 2023 under clear skies, wind NW 8MPH, temp 39F; sunset time 4:13PM
Out on Crow Patrol with scouting visits along Market Street with incoming Crows at sunset time. Arrived South Canal Street a few minutes later to watch early incoming flight streams from the west with growing numbers converging onto the extended warehouse roof and Jackson Lumber roof tops.
As usual, there were intermittent flight bursts from Crows on both roof areas. The helpful aerial views allowed opportunity to see numbers on both rooftops and to assess smaller overall numbers. After dark, moved over to the Mill240 park for views of Crows settled into roost trees, again with ability to observe lower overall numbers. The Merrimack river is running at extreme high levels as seen by submerged tree trunks.
After checking a number of prior roost locations, last stop was to check trees along Marston Street, and bingo, discovered over 4,000 Crows on the hillside tightly converged and quiet in the overnight roost at that location.
This is part of a normal roost transition from the New Balance area to the Marston Street hillside area, the same roost location for most of last winter. This last image below shows an unusual flight burst almost 2.5 hours after sunset time. Another spectacular crow show!
For the 2023 Audubon Christmas Bird Count (CBC) for the Andover Circle, this separate Crow Count was 11,600 total Crows, including American Crows and Fish Crows. In 2022, the CBC Andover Circle Crow Count was 13,750. Many thanks to Donna Cooper who coordinates and compiles the Andover Circle each year!
Note on counts/estimates: we are now using improved methods for counting the large number of Crows while streaming, staging, and in the roost. For all images, we use both a modified open source counting software program, as well as a hand count approach, while outside next to the roost, to carefully document our observations and to significantly increase reliability and accuracy of the presented numbers. Please refer to our new roost counting guide on main page.
The Canon mirrorless cameras with the RF 50mm f/1.2 lens and the RF 28-70mm F2 excel in low-light conditions, blending versatile focal lengths with an ultra-wide aperture. Both focal lengths work extremely well in very low light conditions, while the f/1.2 and F2 aperture settings ensure exceptional performance in low light conditions, offering stunning clear, and aesthetically pleasing images, making them ideal for the challenging very low light conditions around the overnight roost.
For all aerial documentary films with migratory and/or wintering birds or other wildlife, advance project planning and aerial imaging flight mission protocols are subject to rigorous review for “no disturbance” to any flight and perch behaviors, use of high resolution/optical zoom optics, overly cautious altitude/buffer zone levels, and low noise signature levels; all to avoid even the smallest disturbance on these migratory and/or wintering birds.
Remember to check out the latest Crow Patrol Podcast with John Macone (Merrimack River Watershed Council): wintercrowroost.com/podcast/
Photo gear used for most outings:
Canon EOS 80D with Canon EF-S 18-135mm f/3.5-5.6 IS
Canon EOS 80D with Canon EF-S 18-135mm f/3.5-5.6 IS (Infrared)
Canon EOS R6 Mirrorless with Canon RF 28-70 f/2 L IS USM
Canon EOS R6 II Mirrorless with Canon RF 50 f/1.2 L USM