Those of you who read this column may recall me saying that sometimes the best bird sightings occur when you least expect them. I know I’ve said it several times, but I must say it again, because it always amazes me.

Many times I’ve set aside time to go birding, read up on all the appropriate tips – identification, habitat preferences, foraging areas – and spent significant amounts of time watching and waiting – all to no avail.

Yet, let me be in the middle of running errands or otherwise occupied, and the most exciting bird will show up or the most unusual behavior will occur.

Such was the case one day a few weekends ago. I had just left the house to go to the barn. My mind was occupied with what I’d be working on with my horse that day, so at first I did not hear the alarm calls the chickadees were making. When they finally did penetrate, I realized there was a predator in the yard. Seconds later a gray missile appeared behind the house and shot away into the trees.

My heart sank when I realized it was a raptor. I thought I had spooked it.

Thankfully, the bird did not go too far. It flew to a tall white pine and alighted in the topmost branches. In the bright sunshine, the bird’s light chest and slate-gray back stood out vividly against the radiant blue of the sky, contrasting with the deep green of the pine tree. It was an adult northern goshawk.

I was thrilled. I don’t know what it is about raptors that captivates me so much, but a sighting of any bird of prey is at the top of my wish list. Especially that of a goshawk.

This bird is just about the stuff of legend. It appears to be fearless in its pursuit of prey. The “Birds of North America” account describes it as having “courage and extreme aggression … when hunting grouse, ducks, rabbits, and hares” for falconers. When goshawks are able to use the element of surprise, their final attack takes place in the form of an incredibly swift glide, covering up to 24 meters per second. If chasing prey over longer distances, its short, powerful wings and long tail give it superior speed and maneuverability in thick cover, and it will crash through apparently impenetrable thickets to get its quarry.

“Hawks in Flight,” by Pete Dunne, David Sibley, and Clay Sutton, has a great quote regarding the goshawk’s hunting prowess that I’d like to share:

“In the north, in winter, prey is scarce. Something that moves lives. Something that lives may escape but not from a goshawk.”

That says it all, don’t you think?

Goshawks show their aggressiveness in other facets of their lives as well. In all species of raptor, the female is larger than the male; and it is she who defends the nest while the male hunts for food. A female goshawk will readily attack people – drawing blood! – who approach too closely during the nestling phase.

I got another look at the goshawk that day. When it had vacated the pine, I went looking to discover where it went. Having no luck, I was returning when I heard the call notes of an evening grosbeak. Curiously, it was just one bird, and it flew erratically before quickly disappearing from sight. This aroused my curiosity; seconds later, the goshawk glided overhead at tree level. It was so low I could see the very fine gray streaking on its white chest and belly feathers, again providing a lovely contrast against the deep blue of the sky.

It also was quickly gone from sight, and although views of it were brief, I considered myself lucky to have seen this “gray ghost” of the north.

NEWS bird columnist Chris Corio can be reached at bdnsports@bangordailynews.net