What does entomology have to do with bird decline?

Hello, I'm Amanda McNulty with Clemson Extension and Making it Grow. In North America, we've lost three billion (yes, billion with a "B") breeding birds in the past 50 years. Doug Tallamy, an entomologist, someone who specializes in the study of insects, recently spoke about this topic in Columbia. What does entomology have to do with bird decline? Well, 97% of land birds feed their young caterpillars. Even birds that are primarily seed eaters must feed their babies insects. Caterpillars are full of protein, fat, and other compounds and are easy and safe to stuff down a baby bird's throat. To feed a single nest of chickadee babies, the parents have to gather between 6 to 9,000 caterpillars. Working from sunup to sundown, caterpillars are almost entirely found on native plants that serve as larval food sources.