A bumble bee once common throughout Connecticut soon will become the first bee in the continental United States on the federal endangered species list.

The U.S. Fish & Wildlife Service on Tuesday announced that the rusty-patched bumble bee, once found across 28 states from Connecticut to South Dakota and into Canada, has declined so dramatically in the last 20 years that it will receive endangered species protection starting Feb. 10, a month after notification in the Federal Register. Populations of the bee, which has a reddish-orange patch on its back, have plummeted by 87 percent, the Fish & Wildlife Service said.

Megan Racey, spokeswoman for the Fish & Wildlife Service’s New England office, said the designation is significant for states such as Connecticut, where populations already are extinct, because it serves as a warning about the need to protect remaining pollinator species.

“The message for Connecticut residents is the need to take steps to help other bumble bees and pollinator species, by reducing the use of pesticides and using native plants,” she said.

Pollinator species are important for fruit and vegetable crops as well as for many native species. Each year bees and other pollinators provide an estimated $3 billion in pollination services nationwide, according to the Fish & Wildlife Service.

Declines in pollinator species including bees, butterflies and bats prompted the state last year to ban the use of pesticides containing neonicotinoids, a class of chemicals linked to die-offs of bees and other pollinators, said Dennis Schain, spokesman for the state Department of Energy and Environmental Protection. The agency is working on implementation of the law, he said.

Under the law, products containing neonicotinoids cannot be sold in the state after Jan. 1, 2018. After that, products with these chemicals only can be used by certified applicators or farmers with private applicators certification, he said.

Kimberly Stoner, associate scientist at the Connecticut Agricultural Experiment Station, said records from the past 120 years show the rusty-patched bumble bee commonly was found throughout the state. In the 1990s, however, it was declared a species of special concern, and by 2015, it was declared extinct in the state.

“It was widespread across a large geographic area,” she said. “What’s important is that this is not the only species of bumble bee in decline. There are other species in decline that we may not have lost yet, so it’s important to monitor the species we have. We didn’t know this one was in decline until it was gone.”

She said farmers and gardeners are “highly dependent on a small number of bumble bee species” that are in need of attention. To help protect remaining species, she advised residents to plant native trees and shrubs that will bloom in the spring, when the queen bee is actively feeding, native wildflowers that will bloom in summer and avoid the use of insecticides. Grassland habitats also are needed, as well as natural woodlands where bees find nesting areas in abandoned holes made by chipmunks and other small animals.

According to the Fish & Wildlife Service, small, scattered populations of rusty-patch bumble bees still exist in 13 states, including Maine, Massachusetts, Pennsylvania, Maryland and Virginia. Causes of the decline are believed to be a combination of several factors, including loss of habitat, diseases and parasites, use of pesticides and climate change, which affects the availability of the flowers they depend on.

j.benson@theday.com