GREENWICH — An Audubon Greenwich naturalist was greeted on the first of January by a flock of American robins feasting on winterberry holly outside his window.

He’s hoping to teach people how they can enjoy the same.

Robins and other birds that stick around the northeast over winter thrive on a variety of different nuts, seeds and berries, said Senior Naturalist Ted Gilman, who is touting an Audubon program that encourages people to provide and protect resources the birds need to thrive.

“The Bird-Friendly Communities program seeks to enlist people all over the United States in planting a wide variety of native plants, which provide an essential combination of natural foods in all seasons and provide shelter for birds all year long,” Gilman said this week.

Even something seemingly harmless, Gilman said, like sprucing up the yard and attempting to clear debris, can have detrimental consequences for local winter birds.

“People say, ‘Oh the plants are dead, I’ll cut them down,’” he said. “Well, you just cut down a whole bunch of bird feeders.”

Plants from late summer and fall mature come winter, the naturalist said, leaving their flowers and seeds for birds like the dark-eyed junco — which jump on top of them to shake all the tiny morsels they contain down to the ground.

“Every house, every yard. ... is a bird hotel,” Gilman said walking across the snowy Audubon property, pointing out native plants producing winter bird food. “If you have native plants that cover the entire calendar year, you have good accommodations all year long — just like your favorite hotel chain.

“We need to ask, ‘Do we have a full calendar of food?’” he said.

Plants like winterberry holly, American holly, inkberry, bayberry, red cedar and sumac are among those that provide food for American robins, bluebirds and mockingbirds throughout winter — and evergreens provide shelter for these species from dangerous weather and predators.

For information on creating bird-friendly habitats, Audubon Connecticut Bird-Friendly Communities Coordinator Katie Blake can be contacted through email at kblake@audubon.org, and information can be found on the Bird-Friendly Communities section of the Audubon CT website.

Information on native plants that can help feed and protect birds during different times of the year can be found at the Audubon Connecticut website and at the center.

Gilman said bird feeders can help local birds, pointing out a few near the back window of the Hilfiger Children’s Learning Center — where an educational indoor bird-watching area has been set up with treats hanging outside for flying visitors — but they do not replace the natural foods provided by the landscape.

Birds can be found pecking food from trees and plants even in the coldest blizzards.

“We want people to understand the entire landscape of plants has been providing food for birds long before us,” Gilman said. “Feeders are just a supplement for that.”

Email Jennifer Turiano at jturiano@greenwichtime.com and follow her on Twitter: @jturianoGT and Instagram: @greenwichgreen.