I have shared in previous writings my affinity for members of the Corvid family. Corvids are a group of birds that include crows, ravens, jays, and magpies. Of all the birds in that family, I would say Blue Jays are my favorite. Maybe it is because my middle name is Jay, so as a child I felt an early connection to the bird. Or maybe it is because I grew up associating them with summer vacations in the Northwoods. We named our first son Jay, and he has developed a true affinity for these birds as well.
Jays are really fascinating birds. They are a brilliant blue color, in appearance. In fact, like bluebirds, the feathers are not an actual blue color; they have modified prismatic cells on their feathers that scatter light waves, reflecting the blue back out. They have a prominent crest on their head that they can raise or lower depending on their state of mind. They have a variety of songs, although some would argue they are not terribly musical. My favorite call is perhaps their most iconic; it is often described as a rusty gate hinge, but I think of it more like the sound the well pump handle makes at a public campground. The call for which they are named, a piercing “Jaaaay Jaaaay!” served as my alarm clock when camping, signaling time to grab the fishing pole and head for my canoe. They have other less recognizable calls too. Furthermore, the Corvids have shown some ability to mimic other bird calls; Blue Jays frequently mimic hawks but have been documented as imitating other bird species as well.
The diet of Blue Jays is highly variable, depending on the time of year. They love acorns, so in the fall they collect them, carrying three or four at a time to a nearby location where they hammer them into the ground for safekeeping. This is interesting because they are considered a migratory bird, which normally would not bother saving food compared to over-winter residents like nuthatches. We commonly have jays that overwinter here, but they would not be able to access the acorns during the frost and snow period regardless. Perhaps they are caching the food for the early spring.
Jays like other nuts too, as well as fruits and grains, and are happy to come to larger, stable feeders with larger foods like shelled corn or peanuts. They eat insects, small injured or dead animals (like frogs or rodents) and sometimes even other birds. Jays have a reputation of being nest robbers, but recent studies show nestling birds comprise a very small percentage of their stomach contents.
Jays are definitely not welcome around bird nests, though, and are frequently run off by smaller birds protecting their eggs or young. I did a study in college that showed songbirds definitely have a negative reaction to Blue Jay calls when compared to calls of Northern Flickers, a bird of similar size and volume that is not reputed to be a nest robber.
Blue Jays mate for life. The couple shares in the nest-building, and the female incubates the eggs. The male brings her all her food while sitting on the eggs, and during the first several days after they hatch, the male feeds the female and all the chicks. Once the chicks have grown their flight feathers, they travel with the parents as a family group and forage throughout the summer and fall. They demonstrate a strong family bond and are very social within their own family circles.
Blue Jays may not be the most popular bird, with the prettiest songs or the best reputation, but they are strong, hearty survivors that take care of their mate and their family. They are easy to take for granted because they are so common; still, they are a great addition to the variety of birds that surround us.
Jeremy Holtz is a wildlife biologist with the Wisconsin DNR and writes a weekly column in the Star Journal. To contact him, call 715-365-8999.