Editor’s Note: This article was originally published in the Summer 2024 issue of New Hampshire Bird Records. 

Did you know that Black-capped Chickadees feed their young caterpillars not seeds? In the winter, chickadees eat seeds, but when they are raising a family, they feed the babies caterpillars which are soft and full of protein and fat. One pair of chickadees must find 6,000 to 9,000 caterpillars to rear one clutch of young – that’s 350 to 570 caterpillars a day!  

Dr. Doug Tallamy, author and a professor in the Department of Entomology and Wildlife Ecology at the University of Delaware, conducted a study on Carolina Chickadees, a close southern relative to our Black-capped Chickadee. Dr. Tallamy is also an expert on the abundance of caterpillars and the plants they feed on. His research shows that if we don’t have caterpillars, we don’t have chickadees, or the many other bird species that feed their young caterpillars. 

Caterpillars need native plants. Many caterpillars feed on specific plant species and they aren’t adapted to feed on non-native species. According to Dr. Tallamy, some native plants support far more caterpillars than others; 14% of native species support 90% of caterpillars. He calls these keystone species. You can help birds by planting these caterpillar-rich native species such as oaks, cherries, and willows. This simple action could help stem bird declines. Choose the right plants and we can restore insects and the birds that feed on them. 

Dr. Tallamy presented a webinar as part of NH Audubon’s pollinator series. In that presentation, he listed things that you can do: 

1. Cut your lawn in half 
2. Plant for specialist bees (see the keystone plants link below) 
3. Remove invasive species 
4. Use keystone plants (link below) that support lots of caterpillars 
5. Landscape for caterpillars 
   • Leave leaf litter (caterpillars pupate under trees in leaves or underground) 
   • Grow ground covers such as Virginia Creeper 
   • Put big beds around all trees with native ground cover 
6. Reduce your light pollution 
   • Install a motion sensor 
   • Use yellow bulbs (for LEDs be sure they use yellow wavelength, not blue with bulb painted yellow) 
7. Oppose mosquito spraying, even the natural pyrethroids are deadly to all insects 
   • Biocontrol in the larval stage is more effective 
   • Use fans at outdoor gatherings 
8. Minimize insecticide use 
9. No bug zappers, 99.98% of insects killed are not mosquitos 
10. Join your Homeowners Association and change from within 

You can see his full presentation on NH Audubon’s YouTube channel

To find plants for your area check out Native Plants and Keystone Plants.