Crows, Eagles and Red Tail Hawks
An Active Time for Our Local Avian Friends.
It has been a very active time for the birds in Windham and the surrounding region. There has been a Red Tail Hawk hanging around Cobbett’s Pond Road. Donna at Howie Glynn’s also has pictures of this bird near the store. A Bald Eagle has been active over Cobbett’s Pond over the past several weeks, (which means he/she is on Canobie as well). I saw the eagle flying above the lake on Saturday and Sunday this past weekend. An eagle was also spotted by my son Isaac fishing in open water in front of my parents house. There were also four crows strategically stealing parts of the fish that the eagle had so nicely caught for them. And speaking of crows; the great gathering of crows along the Merrimack River in Lawrence will soon be coming to an end. Thousands of crows, return to the same spot on the Merrimack every year to socialize in their giant crow party.
Brian Mertins, on nature-mentor.com says, “Given that crows are so much smaller than eagles, you might be tempted to think eagles would be more dominant…But if you’ve ever watched a group of crows wildly chasing and dive-bombing an eagle through the sky, you know it doesn’t always work that way! Eagles are sometimes seen as royalty of the bird kingdom, so why would a smaller bird like a crow put their life in danger and chase the much larger and threatening eagle? Why do crows chase eagles? Crows do this to protect their nest site from possible danger. They will also steal food from eagles in places where their feeding territories overlap. Of course, to really understand why Crows are able to get away with such a risky behavior, we need to do more detailed comparisons of crows and eagles. This is a way to gain deeper insights into the lives of two incredibly fascinating birds. So let’s take a look at the unique behavior of crows and how their social intelligence gives them anthem the edge against larger predatory birds like eagles….Eagles are relatively defenseless against large gangs of crows. In places where their territories overlap, it’s quite common to see Eagles swooping down to catch a fish, only to have it snatched away by a group of crows. Without any other Eagles around to help in the fight, there’s often no other choice but to go back and catch another meal. You can find the full article at https://nature-mentor.com/crows-chase-eagles/
My wife Kristie bought me just one, really great Christmas present this year; “Gift of the Crows” by John Marzluff and Ton Angell which I recommend.
In an Eaglet Tribune article: “So many crows. So many questions” published on January 28, 2020 we learn the following about the crow gathering in Lawrence: “It’s a bone-chilling sunset in January and 15 men and women, their boots anchored to the snow-covered riverbank, are taking in a spectacle. They watch 15,000 cawing crows breaking into smaller groups and “leap frogging” among trees. Why this knocking around in cliques before settling in for the night — all together — at a final roosting spot along the Merrimack River? Christian Rutz, a biology professor visiting from St. Andrews University in Scotland, wonders about this. And why do the Lawrence crows, on occasion, switch to a new overnight roosting spot? And, more broadly, what brings the crows here? The Lawrence winter roost has been going on for decades, back to the 1980s, says Craig Gibson, a Roman Catholic chaplain at Lawrence General Hospital and dedicated crow watcher. In late fall, the birds start migrating here. Before daybreak they take wing with a few friends and explore locations within about a 20-mile radius. At sunset they return to Lawrence….” Eagle Tribune So Many Crows, So Man Questions
“For decades, the city has hosted a significant winter crow roost. The winter crow roost consists of mostly American Crows, along with a smaller number of Fish Crows. Typically, an hour before sunset, the crows gather in smaller pre-roost groupings. These pre-roost (staging) locations may change on any given night. The crows then converge about a half hour after sunset, into a final roost location. For many years, the final roost location had been along the south side of the Merrimack River, by the New Balance building complex. Over the winter of 2017-2018, and 2018-2019, the final roost location changed many times. Since October 2020, the roost has continued along the Merrimack River by the New Balance building. The size of the winter roost typically grows from an initial group of 2,500 in October to almost 10,000 crows in January and February!” For more information on where to spot the crows in Lawrence go to http://www.wintercrowroost.com/http://www.wintercrowroost.com/
In an article published in Mass Adubon on March 15, 2018 William Freedberg writes: “Every night between November and March, a steady trickle of American Crows pours through the skies of Lawrence and Andover, MA. The trickle quickly becomes a stream. Soon, a deluge. Crows spread from horizon to horizon as they fly together to their communal roost. The number of crows varies every year, but there can be as many of 12,000 or 15,000 at a time…”
“As some of the world’s most intelligent birds, what could American Crows be up to at these roosts? Traditional theories dictate that crows roost together for safety or warmth, or use communal roosts to be able to select mates from a larger pool of candidates. But hungry crows also follow better-fed birds from the roost in the morning, suggesting they are seeking out productive feeding sites, and that roosts can facilitate cooperation. Some roosts are furthermore located strategically near feeding sites, such that crows can grab a reliable snack when they leave for the day and when they return at night.”
“Thousands of crows gathering together in the same place every night make easy pickings for predators like Great Horned Owls. As a result, American Crows gather at a secondary location, or “staging area,” before continuing on to their real roost after nightfall. American Crows will further confuse predators by changing the location of the staging area, or even the roost itself, every few nights. Some human observers confuse these staging areas for the actual roost, not knowing the roost is several hundred feet to several miles away— unless they stay after dark to watch the crows move a second time.”
“The American Crows in Lawrence are surprisingly wide-ranging when not at their roost. Pellets they cough up have revealed saltmarsh snails, telling us that they forage at least as far away as the New England coast. Some of the birds are seasonally migratory, and spend the breeding season far to the north on the St. John’s River in Canada…”