Complex calls of the chickadees and titmice

Many birds fly south in winter to escape the cold and scarcity of food, but Black-capped Chickadees and Tufted Titmice, members of the family Paridae, are year-round residents. In Virginia, after the breeding season ends, chickadees and titmice form loose winter foraging flocks with other species that often include White-breasted Nuthatches, Downy Woodpeckers, and Brown Creepers. The “follower” species travel with the chickadees and titmice because these two “leader” species are excellent food-finders and alert sentinels that help to create a safer feeding environment for the flock.

Downy Woodpeckers (left) and other species that forage with Black-capped Chickadees (right) rely on the chickadee’s ability to find food and spot predators.

These parids share a unique call system to communicate with flockmates — a nasal, mechanical chick-a-dee call. According to an article in American Scientist (Sept-Oct 2012), the chick-a-dee call is one of the most complex signaling systems documented in non-human animal species. The calls are used to communicate information on identity and recognition of other flocks, the finding of food, contact with flock members, and predator alarms. Amazingly, subtle variations of the call even communicate information about the size and risk of potential predators. According to Cornell Lab of Ornithology, the more “dee” notes in a chickadee-dee-dee call, the higher the threat level. The call also serves as a rallying call to summon others to mob and harass the predator.

Tufted titmice (left) use a variation of the chickadee call, a scratchy “tsee-day-day-day”.

The parids are intelligent, adaptive, resourceful, and curious. They are often the first birds at the feeder in the morning and are entertaining to watch as they interact with other birds. Especially in the drab days of winter, the cheery chickadee-dee-dee call is music to our ears.

Countershading helps birds hide from predators

Have you ever noticed that many of our backyard birds including juncos, titmice, mockingbirds, and a whole host of others are dark on top and a lighter shade on the underside? This contrast is known as “countershading.” The coloring can vary from shades of brown, gray, and black above with buff, light gray, and white below.

In nature, everything has a purpose and the purpose of countershading has to do with concealing the bird from predators. In the case of the Slate-colored Junco, for instance, the two-tone countershading breaks up the outline of the bird’s body as a sort of camouflage to help it blend into its surroundings. The top half of the junco is dark so when seen from above (perhaps by a hungry hawk), it blends in with the darker ground; when seen from below, the bird’s white belly blends in with the lighter coloring of the sky.

Slate-colored Junco

Even when viewed from the side, the two-tone coloring of the Tufted Titmouse disrupts the bird’s outline, helping to conceal it from predators.

Tufted Titmouse

Many hawks including the Red-tailed Hawk receive benefit from countershading. Although hawks are at the top of the food chain and so have few natural predators, other predatory birds, such as bigger hawks and eagles, will steal a kill from the Red-tail if they get a chance. Just as countershading helps conceal smaller birds from predators, it helps the Red-tail escape detection by competitors while he finishes his meal.

Red-tailed Hawk. Photo by US Fish and Wildlife (public domain)

It’s interesting to look at the physical characteristics of birds not just from the standpoint of beauty, but from the perspective of how these traits help them to survive. When we understand that a bird’s coloring can help to attract a mate or avoid detection by a predator, it becomes clear that beauty is indeed as beauty does.

Nature is man’s teacher. She unfolds her treasures to his search, unseals his eye, illumes his mind, and purifies his heart; an influence breathes from all the sights and sounds of her existence.” ~ Alfred Billings Street.

winter bird feeding – to feed or not to feed?

It’s always been more or less conventional wisdom that feeding wild birds in winter ups their survival rate because their normal sources of food – seeds and insects – are greatly diminished. But is this wisdom correct? Some challenge this thinking, saying that feeding the birds makes them overly dependent on human handouts and weakens their ability to find food on their own. So what’s a bird-lover to do?

These questions aren’t easily answered, but a three-year study of black-capped chickadees by the University of Wisconsin found that during harsh winters, survival rates were higher when chickadees have both feeder and natural food options; where winters were more moderate, there were no significant differences in survival rates.

Since the late 1800s, many species including tufted titmice, northern cardinals, and white-breasted nuthatches have been expanding their range northward (following the settlers), some making it as far as southern Canada. Evidence bears out that bird feeding played a role in that expansion. Clearly, in these colder climates, supplemental feeding can be important, if not critical, to bird survival.

Nuthatches visit both suet and seed feeders

Tufted titmice are also regular visitors to our feeders

While it would seem “free” food would be irresistible to birds, some of our Virginia resident species, such as mockingbirds and phoebes, tend to shy away from seed feeders, choosing natural food sources instead.

This mockingbird is warning intruders to stay out of his winter food territory. He is protecting several berry bushes nearby.

These species, however, don’t shun feeders altogether. Phoebes have been known to visit mealworm feeders and mockingbirds occasionally come to suet feeders; however, I’ve never had either species come to my feeders. How about you? What atypical visitors have you seen at your feeders?

It’s true that feeders can put birds at risk by increasing their exposure to predators like cats and hawks. But it’s also true that birds that visit feeders eat more in less time than they would in the wild, giving them more time to watch for predators. In addition, birds that frequent feeders where they know cats are nearby keep a watchful eye for the felines and send out the danger signal to other birds when any predator is spotted. You can minimize the risk by keeping cats indoors or placing feeders where they are inaccessible to cats.

Feeders can also cause bird collisions with windows because they lure birds closer to houses and other buildings. One way to minimize collisions is to add tape or decals to your windows so birds won’t fly into them. Distance also plays a role, so place feeders far enough from windows so there is less chance that startled or frightened birds will fly into them.

If you choose to feed the birds this winter, remember that they will be relying on you when the weather turns harsh. The consequences can be disastrous if you suddenly stop, so once you start filling the feeders, continue through until winter’s end. If you are away over the holidays, ask a friend or neighbor to fill your feeders while you’re gone.

What am I going to do? Although I don’t start supplemental feeding until the first snow or hard frost (usually around mid-November), I’m going to feed the birds, as I always do. During periods of heavy snow, ice, or extreme cold, birds have a difficult time finding food and bird feeders can mean the difference between life and death. For me, it’s a no-brainer.