Dec. 22, 2025, a story written by David Wiedner, who has been tracking the local winter crow roost. This article was published in Ink Link, an online newspaper based in Manchester, NH

MANCHESTER, NH – On a recent Wednesday evening on Manchester’s West Side, Craig Gibson stood in a parking lot preparing to launch a thermal-imaging drone. It wasn’t to track down a missing child or lost pet — the plan was to count the thousands of crows that use the area as a night roost.

Gibson, who began photographing and documenting crow roosts in Lawrence, MA, in 2017, had driven up to witness Manchester’s own fall and winter assemblies of these loud and gregarious birds. He joined local bird aficionado Mark Timmerman and the author at a parking lot near Bridge and McGregor streets. Timmerman has been keeping tabs on local crow movements for about seven years; his observations convinced Gibson to pay a visit to the Queen City. An experienced observer of hawks and waterfowl, Timmerman had recently counted 7,800 crows passing over the Amoskeag Fishways on their way to their night roost.

Both Lawrence’s crows and Manchester’s crows have chosen roosting sites near and along the Merrimack River. Gibson co-founded Lawrence’s “Crow Patrol,” a group of residents who watch what Gibson described to the Boston Globe as a “giant avian slumber party.” They are mostly American Crows; a separate species called Fish Crows are also present, but in much smaller numbers. Using disciplined counting methods that he describes on his Winter Crow Roost website, Gibson and others have counted tens of thousands of crows at the Lawrence roost sites. Manchester’s numbers so far are smaller but no less impressive to the casual observer.

Gibson explained that “typically, an hour before sunset, the crows gather in small, pre-roost groupings. These pre-roost (staging) locations may change on any given night. The crows then converge after sunset into the final roost location. Some crows may start as anchors in the final roost just before sunset, and then most other crows join after sunset. They will fly in over the following 60 minutes, until the roost quiets down completely for the night.” He stated that researchers have found that the American Crows gathering at a roost likely spend their day within a 15 to 20-mile radius, but that many wintering crows initially come to the area from hundreds of miles to the north and west.

Timmerman has observed crows coming in large numbers from the north and northwest, loosely following the west side of the Merrimack. To the south, he has seen smaller but still sizable flocks following the Piscataquog River to where it joins the Merrimack at Bass Island on the city’s southwest side. Gibson shared that the roosts typically begin in November and the number of crows increases into January, but then begins to decline in late winter.

Under the roost trees, crow droppings, known as whitewash, is plainly visible, along with what Gibson described as ejected pellets composed mainly of orange-colored remains of fruit from an invasive vine species called Asian Bittersweet. An unfortunately parked car under a large tree in the roosting area exhibited the results of this behavior on its hood and windshield.

Why study crows?

Gibson, who has visited 24 crow roosts in the U.S. and Canada, noted that “crows are among the most intelligent and socially complex birds on the planet, yet much of what they do, especially in winter, happens after dark and goes largely unnoticed.” He added that “observing and diving deeper [into crow behavior] has been a wonderful way to combine curiosity, careful observation, documentation [of] habits, and public education, all centered on a remarkable local natural phenomenon.”

When Timmerman and I mentioned that certain residents of the areas the crows frequent were very aware of their movements and seemed to appreciate the natural phenomenon, Gibson observed that “many locals are certainly aware, but usually with passing interest. Initial reactions are mixed depending on how they interact with the crows. They may be bothered by noise, mess, or smells. The may also have a sense of wonder and awe. Once most locals learn why the crows gather and other background information on seasonal roosting action, how smart and organized they are, then attitudes shift from frustration to fascination. Learning more almost always raises awareness and appreciation.”

Gibson, a former member of the Boston Stock Exchange, said that skills from that job “sharpened my abilities to recognize patterns and movements over time, while my work as a Catholic hospital chaplain taught me how to listen carefully and pay attention to the obvious and not so obvious flow of communications and activities. Studying crow movements requires observing the most subtle behavioral changes and engaging with locals, media, and others nearby about their questions and concerns.”

He estimates that he has spent “thousands of very enjoyable hours over the past nine winter seasons and off season as well” studying the crows, and that “the investment in gear has paid huge dividends as we’ve been able to deploy all kinds of imaging tools to achieve ground-breaking results. The night vision gear and thermal drones have helped us with major new insights after dark with documenting roost movements, counting efforts, and increased public understanding.”

Even with his years of crow observations and interactions with crow researchers, Gibson still has many questions about the crows’ fascinating behavior. “How do crows make instant collective or group decisions? How do they coordinate timing on outbound and inbound flight routes and departure/arrival times? Where do they go each day for foraging and how does that change? What is the exact ratio of American Crows to Fish Crows? What do the different calls mean? Do they stay together as a family each night in the roost? Who are the leaders and how do they lead? Many more questions!”

Over the years, Timmerman has seen the crows use several different pre-roost and roost areas near the river. He wonders why, this year, the crows roosted at first on the small islands on the east side of the Merrimack below the Amoskeag Dam and used trees along Canal and N. Commercial Streets but then shifted to an area less than a mile away to roosts on the city’s West Side. Likewise, I found myself wondering about the crows’ transport of nutrients from one place to another via their droppings and their role in the spread of Asian Bittersweet. Questions like these aside, the impressive spectacle of crows flying en masse low overhead resembled a scene from Alfred Hitchcock’s classic movie “The Birds,” but thankfully without that movie’s more frightening aspects.

Timmerman plans to continue documenting the Manchester crows’ roosting behavior through the winter, while Craig Gibson hopes that Manchester residents appreciate that “these roosts are fascinating, highly organized, and a marvel of nature!”

Manchester resident David Wiedner has held a variety of odd jobs and is currently a recovering attorney. He can be reached at dswiedner@gmail.com