The decline in pollinator populations is a complex environmental challenge. While the managed honey bee receives considerable public attention, the real crisis involves thousands of species of wild, native bees, many of which are solitary and unmanaged. These native populations are experiencing rapid decreases in number and geographic range. Understanding this issue requires examining the specific wild bees that have been formally recognized as threatened with extinction.
Specific Endangered Bee Species
The Rusty Patched Bumble Bee, Bombus affinis, was once common across 28 states in the eastern and midwestern United States. It is recognizable by a small, rust-colored patch of hair on the second segment of its abdomen. Since the late 1990s, the species has suffered a decline of more than 90%, and its current range is limited to a few isolated populations. This population collapse led to its classification as the first federally protected bumble bee in the continental United States in 2017.
The Hawaiian Yellow-Faced Bees represent the only native bee species in the Hawaiian archipelago. More than 60 unique species evolved from a single ancestor that colonized the islands. Seven of these species from the genus Hylaeus were formally listed as endangered in 2016, making them the first bees in the United States to receive such protection. These solitary bees are tiny, and they are important pollinators for native Hawaiian plants.
The decline of these native species highlights the vulnerability of specialized pollinators. Solitary species, like the Yellow-Faced Bees, are particularly susceptible because they lack a large colony to buffer against sudden environmental changes or loss of nesting sites. Limited range also concentrates risk, as a single event can wipe out an entire population.
Primary Drivers of Endangered Status
The population drops among wild bees are attributable to three major environmental pressures: habitat loss, pesticide exposure, and the spread of pathogens. Large-scale farming, characterized by monoculture crops, eliminates the diverse floral resources and nesting sites that native bees require. This practice results in habitat fragmentation, leaving isolated patches of land that cannot support stable bee communities.
Systemic insecticides, particularly neonicotinoids, present a pervasive threat. These chemicals are absorbed by the plant and are present in pollen and nectar, exposing foraging insects to toxins. Exposure to neonicotinoids harms solitary ground-nesting bees, reducing nesting success and offspring production. Wild bees are often more susceptible to these chemicals than the European honey bee, amplifying the impact of agricultural practices on native populations.
The introduction of novel pathogens is a third factor, particularly for social species like bumblebees. The parasite Nosema bombi has been implicated in the decline of several North American bumblebee species. Outbreaks in commercial bumblebee colonies, which are reared for greenhouse pollination, have coincided with increased infection rates in wild populations. This suggests that the movement of commercially managed bees can transmit diseases to wild relatives.
How Bees Achieve Legal Protection
The process of formally recognizing a species as endangered or threatened is governed by the U.S. Endangered Species Act (ESA). This process can be initiated by a petition or by a voluntary status review by the U.S. Fish and Wildlife Service. The determination to list a species is based exclusively on the best available scientific data, with economic impacts excluded from the decision-making process.
To be listed, the Services must determine if the species is threatened or endangered due to one of five factors, such as habitat destruction or disease. When a listing is proposed, the Services must also designate “critical habitat,” which consists of specific areas essential for the species’ conservation and recovery. This designation requires federal agencies to ensure their actions do not destroy or adversely modify the habitat.
The protection afforded by the ESA triggers the creation of a recovery plan. This blueprint outlines the necessary steps to improve the species’ status until protection is no longer necessary. For bees, this often involves restoring native habitat, managing disease, and addressing pesticide use within the species’ remaining range. Listing also raises public awareness, which generates funding for research and conservation partnerships.
The Status of the Honey Bee
The European Honey Bee, Apis mellifera, is the species most people associate with the term “bee,” but its status differs fundamentally from native wild bees. This species is not native to North America, having been introduced by European colonists in the early 1600s. It functions primarily as managed agricultural livestock, with millions of colonies maintained by beekeepers for commercial honey production and crop pollination.
Commercial beekeeping faces challenges, including high annual colony losses due to parasites like the Varroa mite and Colony Collapse Disorder. However, the global population of this species remains robust because beekeepers routinely create new colonies to replace losses. This stability contrasts sharply with the plight of native wild species.
The sheer number of honey bees in a commercial hive—tens of thousands of individuals—can challenge native populations. These dense colonies consume vast amounts of nectar and pollen, potentially outcompeting native solitary and social bees for limited floral resources. While the honey bee is important to agriculture, its population stability stands in stark contrast to the decline of the wild species that warrant the endangered designation.