Butterflies and bees pollinate over 85 percent of flowering plants and contribute to 35 percent of global food production. Bumble bees play a special role in pollination: they work longer days and in worse weather than other bees because of their unique abilities to fly in cooler temperatures and lower light levels. Additionally, bumble bees are the only species that can pollinate plants that require “buzz pollination.” Certain plants only release pollen when a bumble bee attaches itself to the anther of a flower and buzzes its wings at a specific frequency. Tomatoes, blueberries, apples, cranberries, squash, melon, and peppers all rely on the bumble bee’s unique pollinating abilities. A wide range of wildflowers also depend on bumble bees for pollination and continued survival.
The environmental and economic benefits provided by bumble bees are at risk since North American bumble bee populations are in decline. Of the 50 North American bumble bee species, six are losing population and range land. Two of those species, Franklin’s Bumble Bee (Bombus Franklin) and the Western Bumble Bee (Bombus occidentalis), are specific to the West. A loss of either species would stress Western ecosystems and potentially result in the loss of flowering plant species unique to the area.
Suspected causes for bumble bee decline include habitat loss and fragmentation, increased pesticide use, increased prevalence of parasites and pathogens, and ecosystem changes caused by climate change. Bumble bees are particularly sensitive to changes in resource availability. Bumble bee colonies have long life cycles and only produce a few reproductive individuals near the end of that cycle. The entire colony dies at the end of the year and new queens are left to establish the next year’s population. Small changes in the number and types of plants available throughout every stage of a bumble bee’s life cycle have long lasting cumulative effects on colony productivity, the number of new queens produced, and the next year’s population levels.
Within the last few years, the federal government has taken multiple actions to address some of the causes of pollinator population decline.
Regulating Pesticides Under the Federal Insecticide Fungicide, and Rodenticide Act
Of the many chemicals that affect bee health, neonicotinoids are of particular interest to pollinator conservation groups. This class of insecticide is commonly used on agricultural crops, turfgrass, and gardens. The rise in use of neonicotinoids in the early 1990’s correlates in time to the beginning of major declines in bumble bee populations. One study exposed bumble bees to normal field-levels of the chemical and found an 85 percent decrease in new queen production and significant reduction in colony growth. Sublethal exposure levels resulted in decreased foraging ability, food storage, adult health, and brood production.
Insecticides are regulated under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). The Environmental Protection Agency (EPA) is responsible for evaluating a chemical and determining whether “it will perform its intended function without unreasonable adverse effects on the environment.” The EPA began the review process for the neonicotinoids Imidacloprid, Clothianidin, Thiamethoxam, Dinotefuran, and Acetamiprid in 2017 and plans to issue proposed interim decisions in 2019. If the EPA cancels the registration for these widely used neonicotinoids, it will eliminate a large stressor on bumble bee populations.
Protecting the Rusty Patched Bumble Bee Under the Endangered Species Act
In January 2017, the Rusty Patched Bumble Bee (Bombus affinis) was listed as an endangered species by the United States Fish and Wildlife Service (USFWS). The Rusty Patched Bumble Bee is the first and only continental bee protected by the Endangered Species Act (ESA). Its listing is particularly important because of the species’ large geographic range and close relation to other threatened bumble bees.
Historically, the Rusty Patched Bumble Bee was incredibly common in the Upper Midwest Region of the United States. Since the 1990’s there has been an observed loss of the Rusty Patched Bumble Bee from 70 to 87 percent of its historic range and a 95 percent decrease in population size. The reduced population size and range create serious genetic concerns for the Rusty Patched Bumble Bee. Reduced genetic diversity, inbreeding depression, and an issue specific to bumble bee sex determination called the “diploid male vortex” significantly threaten the species’ survival.
The ESA prohibits the “taking” of the Rusty Patched Bumble Bee by both public and private actors. Additionally, the USFWS is now reviewing critical habitat designation which will provide further protections against government actions.
Multiple lawsuits have arisen from the Rusty Patched Bumble Bee’s listing. Although many of them have failed on procedural grounds, the Sierra Club successfully challenged the USFWS’ authorization of a pipeline’s construction across the Rusty Patched Bumble Bee’s range. The Fourth Circuit Court of Appeals held that the USFWS failed to meet its requirement to set a specific numeric take limit: “[N]either one colony nor a small percent is an enforceable standard: There may be multiple colonies within the [affected range], [the Government] cannot know if taken bees are from the same colony or different colonies, and it is not clear what constitutes a ‘small percent’ of queen bees.”
This case is only the first of many developments critical to understanding how the listing of the Rusty Patched Bumble Bee will impact pollinator protection. Previously unprotected, bees have recently gained particularized federal protection under the ESA and potential protection under FIFRA. Unanswered questions remain concerning the impacts of these changes on bumble bee conservation. Ideally, additional protections for more bee species and other pollinators are on the horizon.
Daniel Franz is a rising 2L at Colorado Law and a Staff Writer for the Colorado Natural Resource, Energy, and Environmental Law Review