This is Bird Note.

A tiny Nashville warbler flies to its nest, a fat caterpillar clamped in its beak.

Nearly all of North America's smaller birds, from this warbler to chickadees to thrushes,

raised their young on insects, especially insect larvae, like this juicy caterpillar.

Insects sustain our ecosystems, and not just as a food source. They also pollinate 90% of all plants,

and without plants at the heart of the food web, life on earth would simply collapse.

Though insects are small, easily overlooked, and often vilified, most are beneficial,

but their numbers have dropped by half in the last 50 years,

so it's now critical to help foster insects.

One concrete way to help is to grow native plants that provide food and shelter for insects like caterpillars.

For example, in the eastern United States and Midwest,

buttonbush supports 18 different species of caterpillars and also provides

food for birds in the form of nectar and seeds. Growing such plants directly benefits birds

and helps insects keep the natural world ticking. For Bird Note, I'm Mary McCann.