Pollinator Week: Birds, Bees, & Everything in Between

It’s National Pollinator Week! National Pollinator Week is an annual event celebrated from June 19th through June 25th to honor the unsung heroes of our gardens, fields, and farms.

Over 100,000 invertebrates—including bees, butterflies, beetles, moths, wasps, and flies—and more than a thousand mammals, birds, reptiles, and amphibians take on the job of pollinating plants. 

At least 80% of all flowering plant species need the help of wildlife to move their heavy pollen grains from plant to plant for fertilization.

Bees

Worldwide, there are an estimated 20,000 species of bees, and approximately 4,000 bee species are native to the United States. As they forage, bees perform the critical act of pollination. In fact, bees pollinate a staggering amount of all flowering plants, including many fruits, nuts, and vegetables grown in the United States.

Bumble bees are important pollinators of wild flowering plants and agricultural crops. They are characterized by their rounded, fuzzy bodies and their ability to perform “buzz pollination,” which involves grasping a flower in their jaws and vibrating their wing muscles to dislodge the pollen. Many plants—including a number of wildflowers and crops like tomatoes, peppers, and cranberries—benefit from buzz pollination.

Fun fact: Some species of bee employ a technique called sonication, or buzz pollination, when they harvest pollen. The bee rapidly vibrates its flight muscles while attached to the flower which loosens the pollen, making it easier to collect.

A bee perches on a flower.
A Hunts bumble bee nectaring on rubber rabbitbrush flowers at Seedskadee National Wildlife Refuge. Photo credit: Tom Koerner/U.S. Fish and Wildlife Service

Hummingbirds

Hummingbirds are amazingly adapted pollinators and play an essential role in pollinating many plants. They have long, slender bills and tongues with a two-pronged, feather-like tip that they use to drink nectar from brightly-colored flowers. They drink up to two times their body weight per day. As they move from plant to plant, they carry pollen. As they pollinate native plants in the wild and in your garden, hummingbirds add a splash of color to our landscapes.

Most hummingbird feeders are red to mimic the blooms of the native plants they naturally feed on. In addition to flower nectar, hummingbirds also rely on tiny invertebrates as a key food source, including mosquitoes, flies, and spiders.

In North America, ruby-throated hummingbirds populate the eastern United States; common species in the west include broad-tailed, rufus, and black-chinned.

A hummingbird hovers next to a flower, beak extended into its petals.
A ruby-throated hummingbird collects nectar from a native anise hyssop plant.

Monarch Butterflies

The monarch butterfly is one of North America’s most iconic species, with vibrant orange-and-black wings that streak across the sky. The impressive monarch makes a multi-generational 3,000-mile migration, traveling south to Mexico each fall and back up to Canada in the spring.

As adults, monarchs feed on nectar from a wide range of blooming native plants, including milkweed. Milkweed produces glycoside toxins to deter animals from eating them, but monarchs have evolved immunity to these toxins. As they feed, monarch caterpillars store up the toxins in their body, making them taste bad, which in turn deters their predators. The toxins remain in their system even after metamorphosis, protecting them as adult butterflies as well.

Monarchs have suffered a population decline upward of 90 percent in recent decades. The decline is inextricably linked to a decline in milkweed. Without milkweed, monarchs can’t complete their life cycle, and populations plummet.

An orange, yellow, and black monarch butterfly rests on a flower.
A newly emerged monarch butterfly on a Rocky Mountain beeplant at Seedskadee National Wildlife Refuge. Photo credit: Tom Koerner/U.S.Fish and Wildlife Service

Native Plants and Climate Change 

Pollinators are impacted by climate change in a number of ways. Warmer temperatures can encourage plants to bloom sooner than usual. Not all pollinators can adapt to an early blooming season, which means that many pollinators may have limited food availability from plants.

Pollinators are also vulnerable to periods of drought. With warm weather and low precipitation, flowers produce less nectar to conserve energy. Reduced nectar means that pollinators get fewer calories and sugar which can lower reproduction.

Native plants have formed symbiotic relationships with native wildlife over thousands of years, offering the most sustainable habitat. Native plants help the environment the most when planted in places that match their growing requirements and will thrive in your region’s soils, moisture, and weather.

A striped caterpillar rests on a plant.
Monarch larva feeding on butterfly milkweed in Payne County, Oklahoma. Photo credit: Ray A. Moranz/USDA/NRCS

Bats 

Most people associate pollination with bees and butterflies but often forget the work of their furry colleagues: bats. Not all bats eat insects. Some live on a diet of nectar and fruit. Bats that feed on nectar also serve as pollinators to nighttime blooming plants.

Bats take the night shift, playing a major role in pollinating crops. So naturally, these bats feed on flowers, including those of valuable commercial crops, like figs, dates, bananas, and mangoes which have flowers that only open at night. In North America bats pollinate agave, which is used to make products like tequila, mezcal, and agave nectar.

Throughout time, plants and mammals have shared a dependency on one another that is mutually beneficial.

A bat in flight is about to land on a flower.
Lesser long-nosed bat. Photo credit: Merlin D. Tuttle/Bat Conservation International

Wasps 

As the poster animals for the plight of declining pollinators, bees are much beloved by the public. Did you know bees evolved from wasps? Yes, wasps are pollinators too.

Wasps, like bees, have very high-energy needs that must be met for their survival. They need key resources such as pollen and nectar from a variety of flowers. Many wasps feed on flower nectar, but unlike bees most species are also carnivorous or parasitic, feeding on other insects (including pests) and spiders.

Many wasps are smooth-bodied and do not actively collect pollen. Those with hairs lack the branched, pollen-trapping hairs found on most bees, making them relatively minor pollinators of most plants.

Nonetheless, they do provide pollination, carrying and dropping some pollen grains as they move among flowers.

A wasp with a yellow-orange band on its lower abdomen rests on a yellow flower.
Thread waisted wasp on rubber rabbitbrush at Seedskadee National Wildlife Refuge. Photo credit: Tom Koerner/USFWS

For further information on pollinators, native plants, and other helpful resources: