For Part I of this Blog series click HERE
CAW CAW CAW!! CAW CAW CAW! CAW CAW CAW!! CAW CAW CAW!! I heard in the distance one afternoon several summers ago, as I wandered through a Seattle city park with a group of fellow naturalists. CAW CAW CAW!! CAW CAW CAW! A cacophony of agitated crow vocalizations relentlessly rang through the trees.
We made our way towards the ruckus with intent curiosity, and nodded with a sense of satisfaction as our suspicions were confirmed: there, perched in a Western Red Cedar tree, was a Barred Owl. Surrounding him on all sides were dozens of “cawing” crows.
The “caws” increased in volume, pitch, and intensity as the owl fled to a new perch in a nearby tree. The crows followed the owl and surrounded him once again in the branches. The “cawing” continued, and the scene carried on as the owl tried to make his escape. These theatrics trailed through the forest as the owl pressed on from perch to perch in his efforts to evade his rowdy rivals.
At the time I was new to bird language, but it was clear to me that the crows were very, very agitated by the owl. The owl obviously had ticked them off. Considering that the crows were deep in nesting season that time of year, it’s likely that the owl was attempting to devour a tasty baby crow that had yet to fledge. The crows’ body language towards the owl was clear: “You ain’t getting our baby, buddy! No way, no day!” The vocalizations and behavior of the crows indicated that they were utilizing the voice of alarm in order to communicate this sentiment. The crows, being voracious nest robbers themselves, will push out any and all threats with authority during their nesting season.
As I mentioned in my last blog post, there are 5 fundamental voices of birds: song, companion calling, juvenile begging, territorial aggression, and alarm. The first four voices are considered baseline. A bird or group of birds expressing one of these baseline voices are generally going about business-as-usual, unaffected by any life-threatening scenarios.
The fifth bird voice, alarm, is a deviation from baseline and an indication that the bird or group of birds using this voice and its variations is experiencing a life-threatening disturbance of some sort. (Watch Jon Young talk about bird baseline vs. alarm)
Bird alarms are a fascinating learning tool for animal trackers and nature geeks who are interested in connecting with the seen and unseen “stories” of the forest. Oftentimes bird alarms can clue us humans into the presence of predators such as stealthy owls, cats, or weasels who are otherwise difficult to locate firsthand. Birds are the ultimate scouts and trackers, hence why bird language is so cool! You just have to know how to turn the dial on your awareness “radio” and tune into the bird’s “broadcast”.
Bird alarms have different variations or “shapes”, which offer the observer insight on the particular predator or threat that is triggering the alarm. Experienced bird language enthusiasts can become quite tuned into these intricacies and are able to draw accurate conclusions about the presence of specific predator species based on particular bird alarm shapes. Bird language truly is a reputable science!
I have yet to reach such a level of expertise (though I’m becoming pretty spot-on in my predictions of crow and Stellar’s Jay alarms triggered by owls or house cats! Pat was surprised just yesterday that the crazy Stellar’s Jay alarms revealed a day hunting raccoon in the forest.) I’m more of an enthusiastic bird language amateur who is excited to share with you this intriguing way of connecting to the natural landscape. (Check out Jon Young’s book What the Robin Knows if you want to learn from a REAL expert!).
Today I’d like to share 5 categories of common shapes of bird alarm that you’re likely to witness if you choose to tune into the bird language “broadcast” on an average day in a suburban or urban park, as well as some explanations on what these shapes may be implying about seen and unseen dramas taking place in the forest:
1. Parabolic: Ever notice when a group of birds form a bubble or gang amongst the trees and shrubs and start making irritated noises at something below them? This is a “parabolic” shape of alarm, likely caused by a “nest robber” such as a house cat, a hawk or a owl. My story above about the “cawing” crows and the Barred Owl is a quintessential example of this alarm shape. I have witnessed crows and jays engage in this shape of alarm countless times, and whenever I follow the source of this alarm it always reveals either a cat or an owl!
2. Bird Plow/Hook/Popcorn: So, you’re jogging on a trail (or tromping through the woods with your kiddos and/or your dog) and suddenly a group of Juncos or Towhees pops up from the ground or bushes and flies down the trail away from you. Just like that, they all take off in the same direction. You didn’t even notice they were there! This is an example of a “bird plow”, and oftentimes inattentive humans and their dogs are the trigger. A variation of this alarm posture is known as a “hook”: a bird or group of birds hops up from the ground or bushes and lands just above and out of reach of you. As you travel along a trail you may trigger a sequence of hooks, as several songbirds successively pop up from their lower spots and onto higher perches. This is known as a “popcorn.” (Next time, try fox walking instead of tromping, and see how the birds react!!).
3. Sentinel: You’re lounging in a park meadow, taking in the sunshine, when you look up and see a Robin or a Flicker perched up at the very top of a tree. The bird stays there for a very long time, looking intently in the distance. This is an example of “sentinel” behavior. The bird remains silent but his body language shows that he’s in a posture of alarm. He’s getting a clear view of a potential predator from a safe distance. His body language communicates with other birds that a threat may be looming in the distance.
4. Oppression/Tunnel of Silence: You’re walking through the woods on a gorgeous sunny morning, and you notice that the forest is eerily silent. Where are all the birds? you wonder. Why aren't they singing as usual? Perhaps it’s because a Cooper’s Hawk is perched in a tree nearby, ready to pursue the next songbird he sees. This “pillow” of silence that is present is known as “oppression”. The complete lack of bird vocalizations is an alarm in an of itself, as nearby songbirds silently communicate with one another that a hungry hawk is nearby without revealing their own presence. (Watch Jon Young talk about oppression). As the hawk takes off from his perch and weaves through the forest, he may create a “tunnel of silence", or a trail of quiet oppression behind him.
5. Bullet/ Ditch: You’re taking in the scenery as you wander through the forest, when suddenly out of the corner of your eye you notice a group of songbirds quickly flying straight away from something. This formation is known as a “bullet,” and it likely implies that these birds are fleeing for their lives from a Cooper’s Hawk or a Sharp-shinned Hawk as it makes its way through the forest. A variation of this shape of alarm is known as a “ditch”: the birds fly away from the predator and dive into shrubs for cover, where they can remain still and quiet as the hawk passes through.
Well, there you have it fellow bird nerds, some common shapes of alarms that you might come across while you're out exploring. I'd love to hear YOUR bird language stories when you get chance. Notice any shapes of alarm out there?? Please share in the comments below!
For a more in-depth exploration of bird language, check out these resources: