Black-capped Chickadees (Poecile atricapillus) are among the most tenacious of all the birds. They can be seen in the dead of winter with temperatures well below zero hopping around when every other species has either retired to hibernation or has retreated to shelter. They will pick hair directly from wolves, bears and other mammals to make their nest. Their cheery calls and song are among the first to be heard in the spring, often with snow still on the ground. Chickadees are, for lack of a better description, bad asses.
This last fall I attached a bird house that hung at my grandparents house in a first-tier suburb of Minneapolis for nearly 50 years. I can remember seeing English Sparrows in this house growing up. The house has been so well used the the original hole has been pecked/chewed so wide that a replacement hole has been attached to the original. Even that replacement hole has been resized and shaped by occupants or those seeking access.
This spring I found the chickadees took up residence in this newest box in my yard. They ignored the chickadee specific house where they nested last year, and the renovated Wren house they used the year before that. This year they chose the new box hanging on my deck. This was a spectacular opportunity to document their story just feet from my back door.
Building the Nest
Chickadees use moss hair and other similar material to create a well insulated nest in a small tree cavity or nest box. They often use nest cavities that had previously been used by Downy Woodpeckers or find natural cavities in trees or stumps.
This picture was taken on April 18, 2012
This nest is a testament to the awareness and tenacity of these little birds. There is rabbit hair clearly visible to near the right corner. The rabbit hair is not just from the back but also the underside. There is also what appears to be dog or human hair (the long brown strands). Additionally there are dried leaves, moss and some synthetic fibers. I try to imagine a little chickadee flying around a freshly killed rabbit with the coyote, fox or other predator near by. The chickadee fearlessly swoops down to pluck a tuft of hair and returns to the nest.
I could tell that the nest was complete and I knew that the eggs would soon follow. Every morning the chickadees would sing in the sunrise I listen to their song every day. One day the male was singing just a little more proudly than previously. The song was just a little bit louder with a little more vigor than in previous days, something had changed.
Sure enough, upon investigation I found seven tiny speckled eggs tucked deep in a cozy cup in the nest.
April 20, 2012
Notice the shift in the nest construction to accommodate the eggs and how the nest now serves as an insulated incubator. The female chickadee diligently incubated her clutch for 14 days. She was unphased by the mysterious ape that opened her nest each day. She would simply push a little deeper into her precious eggs that stayed tucked beneath the safety of her weight.
April 24, 2012
On May 4, 2012 the chickadees began to hatch. My wife and daughter checked the box early in the morning and found one lone hatchling surrounded by its six siblings still locked in a shell of calcium carbonate. When I checked later in the day five of the seven had made their appearance. Entering the world naked, blind and barely able to support their own weight. Despite their weak appearance they already contain all the instructions and behavior to ensure their survival. They instinctively raise their heads, mouth agape for any opportunity to be fed. Their white lips around their tiny beaks serve as a target for their parents to deposit food. It ensures that the food reaches the mark in a dark nest box.
May 4, 2012
Feeding the Brood
Over the next twelve days the parents kept a nearly continuous delivery of caterpillars and other insects to the nest. The male would tolerate our presence outside and fearlessly delivered even with our proximity to the nest. The female, however, refused to enter the nest if we were any where in sight. She would nervously call with a beak laced with several caterpillars. The chicks grew quickly, the following photos illustrate just how quickly they changed from the naked helpless hatchlings into a more familiar looking form.
May 6, 2012: 2 Days Old
You can already see the tufts of fuzz around their heads that will serve as the base layer of down to keep them insulated even against temperatures of 30 or 40 below zero. Their tiny wings remain completely naked and useless.
May 7, 2012: Three Days Old
Note the change in one day. The wings are showing the first signs of feather production. The thing dark lines one the edge of the wings are the first signs of formation of feathers. Feathers develop in a similar manner as reptilian scales, an indication of their common ancestory with reptiles and more specifically dinosaurs.
May 9, 2012: Five Days Old
The wings now show clear evidence of flight feathers and the skin has darkened a sign of yet more feather production. The development is controlled by a very specific sequence of genes that are activated at a specific time. The exact same gene, activated at a different time, can result in a completely different structure. Evolution in action!
May 10, 2012: Six Days Old
Wings are now clearly defined with developing flight feathers. The feathers have begun to emerge around the head and body as well.
May 11, 2012: Seven Days Old
I love this picture because it clearly shows the feathers as a modified scale. These little spike-like scales will continue to develop into feathers. Modern birds really are little dinosaurs that can fly!
May 14, 2012: Ten Days Old
The contour feathers, the feathers covering their bodies continue to develop. Each day they make incredible changes, a testament to the dedicated stream of caterpillars from their parents.
May 15, 2012: Eleven Days Old
After eleven days without eyesight their eyes finally open and they see the world for the first time. The left most chick in the picture below is peeking one eye open. Others have not yet reached that developmental milestone. The characteristic white cheek feathers unique to chickadees have also begun to appear.
May 16, 2012: Twelve Days Old
For the first time they actually look like miniature versions of their parents.
May 17, 2012: Thirteen Days Old
A cold night left them tucked deep in the insulated nest. Remember there are seven chickadees in this picture!!
May 18, 2012: Fourteen Days Old
A hot day with temperatures well into the 90’s caused the little birds to find some space and cool down a bit. They have begun to explore the next box beyond the small cup where they have been since they were still in the egg. You can see their small tail feathers and well defined wings. Just a few short days before those feathers looked more like scales than feathers of a bird.
May 19, 2012: Fifteen Days Old
Another day of heat spread them away from each other. They are beginning to show signs of leaving. They eagerly look up, away from the nest. Only a few more days…
May 20, 2012: Sixteen Days Old
A cold night brought the brood back together for one last time. Their collective body warmth ensure survival of the entire brood with nighttime temperatures in the low 40’s. The now look like chickadees and will soon fledge into the outside world.
May 21, 2012: Seventeen Days Old
A parting shot. This is the last picture I took of the brood before leaving the nest. They look eager and ready to leave the tiny cavity in which they have developed. The moment they poke their head out of the hole they must fly. There are no branches or practice flights, the must just go, go into the unknown.
When the chickadees enter the real world they will have the support of their parents for several days. They will learn to find food and survive whatever Mother Nature can throw at them. They will be the next generation of bad ass little birds showing us what survival looks like in the dead of winter. Chickadees have been recorded as old as 10 years in the wild, a testament to their sheer tenacity and ability to survive despite weighing little more than an ounce.
All that remains for the chickadees is a dropping released just before take-off from the nest hole. My backyard has been much more quite but I have still seen several chickadees meticulously searching the trees for juicy caterpillars and other insects.