If ever there was a bird that embodies the phrase "little brain, big heart," it's the black-capped chickadee These popular year-round residents of the Eastern United States and Canada are renowned for their intelligence, and it's no wonder that they're often featured on t-shirts and other merchandise They're also notoriously resourceful, and that tapping you heard in your wren house may have been the sound of a chickadee remodeling it for its own use
 
 The eponymous black-capped chickadee is an obligate cavity nester, and the birds typically build their nests in tree cavities or enlarge existing holes In the absence of suitable natural cavities, chickadees will also nest in prefabricated birdhouses, such as those designed for bluebirds Those who keep bird feeders will often see chickadees perching on or near them, and they'll usually take the food offered by their hosts — but then they'll stash it in one of several different hidden locations to consume later
 
 A typical ***-shaped nest has a base of twigs and rough materials such as fur, mammal hair, or bark, and is lined with softer material such as moss or animal hair The nest is built by the female, who alone may construct a new nest in as little as a week The nest is typically located 4-14 feet above the ground, and the female will help excavate or enlarge a suitable hole The male helps feed the female while she builds the nest, and both mates are involved in defense of their territory
 
 Chickadees are non-migratory and can be found year round in their breeding range which stretches from New England to Alaska and all the way south to the mountains of Tennessee and northern New Mexico They're attracted to many of the same habitats that attract other songbirds, including deciduous and mixed forests, groves of cottonwood trees, and birch and beech forests
 
 In fall, black-capped chickadees form mated pairs that will remain together throughout winter and breed in the same general area Pairs begin searching for cavities in mid-March and by early April, they're beginning to build nests By early May, eggs are hatching and young chicks are fledging by late July
 
 The Black-Capped Chickadee is a common species that's not currently listed as threatened or endangered But climate change is expected to alter the habitat of many birds and the black-capped chickadee will be no exception Audubon is working to reduce the impact of climate change on wildlife through our Survival By Degrees project Learn how you can join us in this work
 
 At the Arboretum, we're working to improve the chickadee habitat through our landscape work and by installing "chickadee tubes" in many of the wren houses on the property Each year, the Arboretum's NestWatch volunteers track the activities of chickadees in these tubes and in a number of other "chickadee-friendly" birdhouses on our grounds Visit  https//nestvuicom/yen-sao-khanh-hoa/  or summer to watch chickadees in action