Refuge Notebook

Article
Dated February 27, 2004

Unexpected Encounters: Aggressive Grouse Defends Territory
By Ted Bailey

One never knows what to expect in nature; a sudden encounter with the unexpected is one of the reasons I enjoy walking in natural environments. As one of my daughters used to say long ago when she was a child, "You never know what you're going to see." She would say this when I sometimes took my family with me into the field while studying leopards in Africa. She was then repeating in her own way my own mantra to them, which was an attempt to keep our children captivated by the unique African animals we often observed.

My walks on the Kenai Peninsula seldom result in close encounters with nature's creatures; most, if any, encounters are long distance experiences. However a recent exception to this rule occurred when my wife and I were walking through a wooded area on January 29. After steadily walking along we paused to talk and take in the beautiful snow-covered scenery. While talking to her I noticed out of the corner of my eye that a rather large bird had just landed on the snow about twenty feet behind her. At first it was partially hidden. I told her a bird had landed behind her and I thought it was a bold gray jay. But soon after, from behind a small spruce tree walked a daring spruce grouse directly toward us. In a few minutes it was only ten feet from us and I knew then it was a male by its flaring bright red "eyebrows." It was obviously intent on encountering us. Since my wife was wearing a bright red parka I told her she had probably attracted a territorial male grouse intent on defending his territory. Soon the bird was at her feet, jumping up several times to buffet his wings against her legs, scratching her clothing with his feet and pecking at her with his beak.

Needless to say, my wife did not share my utter fascination with this sudden encounter. So we switched coats and the grouse quickly switched his attention to me instead of her. He "attacked" me several additional times and twice I reached down, grabbed him in my hands and tossed him into the air. He immediately went into a "hover" at a height of about eight feet and quickly landed again at my feet. All the while he was periodically vocalizing with guttural "chirring" sounds and spreading and flicking his tail. After about twenty minutes we walked away. He followed us by walking behind us on the ground until we reached a small gully. There he stopped, apparently convinced he had "removed" us from his territory.

I was certain that my wife's red parka had triggered a "territorial defense," an instinctive behavioral response in grouse because we had both witnessed a similar response over ten years earlier when another male grouse in a different area similarly "attacked" me when I was wearing a bright orange wool cap. But that occurred later in either March or April and this was only January. I returned with a camera the next several days but no grouse appeared and I considered our experience another "one time encounter."

However, my "attractive-red-clothing-hypothesis" for initiating the grouse's territory defensive behavior was shattered on February 8 when my son and I were again walking through the same area. Neither of us was wearing any visible red clothing. The grouse suddenly appeared again, vocalizing and displaying as it proceeded to "attack" us, buffeting its wings against our legs as in the previous encounter. Again I picked up the bird in my hands, tossed him into the air and he immediately landed at our feet. To condense an ongoing saga, the grouse responded to our presence in a similar fashion on February 9, 11, 12, 16, 18 and 20.

The boundary of his territory was distinct; he would not venture out of it nor concern himself with us beyond this invisible boundary. Most "attacks" were initiated in the center of his territory when we or I paused there for several minutes. A person continuously walking through the area without stopping probably would not even be aware that a grouse was nearby. To confront us, or me if I was walking alone, he either walked on the snow out of a dense stand of spruce trees or less often flew down from taller mature spruce trees nearby. I paced the length, perhaps the diameter of his territory, and it was at least eight hundred feet. On my February 20 encounter he escorted me out of his territory by walking its entire length.

What is one to make of such behavior? It is primarily an instinctive behavioral response, which means the grouse is merely reacting to a stimulus, in this situation our presence, with or without red clothing, in his territory. Instinctive behavioral responses are "hard wired" into an animal's brain circuits like circuits in your computer; once they are initiated they usually cannot be stopped and run their course. Our impulse to run when suddenly encountering a bear is a similar instinctive response that we are told by bear experts to "override" in our brains by our hopefully learned behavior.

In The Birds of North America: Spruce Grouse, grouse experts David Boag and Michael Schroeder discuss behaviors and sounds made by territorial male spruce grouse. One is a pecking sound made by the male's beak when it pecks aggressively at the ground or inanimate objects; the grouse I observed repeatedly pecked at the snow while it displayed in front of me. Another display I observed was the tail-flick display produced by a rapid simultaneous lateral displacement of all the retrices in an exaggerated fanning of the tail. This was accompanied by vocal "chirring" sounds.

Another observation the authors mention is that rather than flying, spruce grouse prefer to walk when moving from place to place, a fact exemplified by the male I observed that walked over eight hundred feet to escort me from his territory. When an intruder starts to flee, which I sometimes did to elicit this response, a male will run toward the intruder with its plumage slicked down. Others have gotten male spruce grouse to attack their own image in a mirror with their feet, bill and wings focusing on the neck, head and back of the "intruder.”

Territories are most aggressively defended during the breeding season, but apparently they may be defended year round. Territorial behavior is related to the level of circulating hormones (androgens) in males, and not all males, especially yearling males are territorial. This particular grouse apparently has a high level of circulating androgens. His territorial behavior has fascinated me for nearly a month and has enriched my experience walking in the winter, exemplifying what my daughter once said: "You never know what you're going to see".

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Ted Bailey is a retired Kenai National Wildlife Refuge wildlife biologist who has lived on the Kenai Peninsula for over 27 years. He is an adjunct instructor at the Kenai Peninsula College and maintains a keen interest in the Kenai Peninsula's wildlife and natural