This has been a great year for sighting irruptive migrants. Bohemian waxwings, pine grosbeaks, redpolls, snowy owls – and now northern shrikes are being reported throughout the state.

Just last week someone sighted a shrike off of the Witter Farm Road in Orono. In this case, the shrike was a bonus in addition to a view of a snowy owl in the same area. It pays to be in the right place at the right time!

Of course, I went in search of both birds, but so far have not found either. I seem to be going through a bad run of birding luck.

Two species of shrike occur in the United States – the loggerhead, a bird of the west and the southeast, and the northern, which nests in the far north. Every couple of years, the northern shrike comes farther south in response to local food shortages.

The shrike is a fascinating bird. It is a songbird about the size of a robin, and resembles the mockingbird in coloration. However, it has the strong, hooked beak and keen eyesight of a falcon. It also has the appetite of a bird of prey – small mammals and other birds as large as mourning doves may be taken.

The one physical feature the shrike lacks are the strong talons that a raptor uses to capture prey. Instead, the shrike will deliver sharp blows of its beak and a killing bite once the prey is immobilized.

Consumption of prey involves a unique habit that has earned it the nickname of “butcher bird.” Because it lacks strong feet and talons, the shrike will impale its food on a thorn, barbed-wire fence, or other sharp object to anchor it while it eats.

The shrike will also store its food this way. If you ever come across small animals stuck to sharp objects in this manner, chances are it is a shrike’s “larder.”

Researchers have observed shrikes storing many food items in this way as preparation for lean times; the birds will even come back up to eight months later to check their larders. During freezing weather, the shrike will tear off small bites of food to be stored, thus making it more accessible than one large, frozen hunk would be. Smart bird.

It is also thought that male shrikes will create larders to attract a mate.

Like many other species we share our planet with, shrike numbers are in decline. Habitat loss, pesticide use, and highway mortality are among the culprits. So is interference. Although the bird doesn’t mind utilizing areas of human habitation for food during the winter, during the breeding season, it refuses to nest anywhere near us.

So, keep an eye out for this gray, black, and white songbird with the sharp, hooked beak this winter. Appreciate it for what it is – another wonderful adaptation of nature.

Thanks to everyone who called in their sightings of snowy owls seen in Belfast, Ellsworth, Brewer, Orono, and the Bangor Mall area. Again, it – and any other birds – can be reported to the Fields Pond Nature Center, at 989-2591.

Happy birding!

Chris Corio’s column on birds is published each Saturday. Corio, a volunteer at Fields Pond Nature Center in Holden, can be reached at fieldspond@juno.com