Bonneville Power Administration

06/25/2020 | News release | Distributed by Public on 06/25/2020 17:44

Murder hornets threaten pollinators, but you can help save them


Mount Hood near Odell, Oregon. But the bees and wildflowers stole the show. Photo by Jesse Byron, Transmission Services.

Yes, we did use 'murder hornet' in the headline for dramatic effect to entice you to read about all of the threats to pollinators, including loss of habitat, other predators, pesticides and herbicide use, and climate change.

Giant Asian hornets
, or murder hornets, whose native range extends from northern India to East Asia, are not just scary to humans, but attack and destroy honeybee hives. Anest of this invasive species was found in August 2019 near Vancouver Island, Canada, and two other nests were detected in the state of Washington, according to the U.S. Department of Agriculture.

What are some of the threats to pollinators?

While the giant Asian hornet is an example of an exotic threat to pollinators, it is not nearly as common as other factors that are contributing to their decline.
According to the Xerces Society for Invertebrate Conservation, pollinators are declining at an alarming rate throughout the U.S. and globally. Dozens of pollinator species are already listed under the Endangered Species Act, and the U.S. Fish and Wildlife Service is also considering listing the monarch butterfly under the ESA.

Exposure to parasites and pesticides, disease, loss of floral resources that serve as food, nectar and hosts, and habitat removal are all factors contributing to the decline.

Climate change is also affecting pollinators. In some instances, it affects the behavior of pollinators, and it alters the blooming time of some plant species. For example, in some areas, flowers are blooming before native mason bees hatch and have the opportunity to use the floral resources.

While the threat from four-centimeter giant hornets may be terrifying, please don't kill other insect pollinators, including our native bees (all smaller than the giant hornet). Even our native wasps are very helpful, providing pollination services and killing insects that prey on native bees.

What is BPA doing to protect pollinators?

BPA has developed pollinator-friendly best management practices for transmission facilities that cover maintenance, construction and vegetation management. One example of the agency's efforts to protect pollinators includes its work to safeguard Taylor's checkerspot butterfly habitat in the Santiam-Toledo transmission line right-of-way. You can read more about this project in the book 'Attracting Native Pollinators: Protecting North America's Bees and Butterflies,' by The Xerces Society.

BPA has also updated its landscaping policy to prioritize planting native plants to save water consumption, in addition to supporting pollinators.

In addition, BPA funds projects that enhance pollinator habitat through its Fish and Wildlife Program. This includes projects implemented by the Methow Salmon Recovery Foundation, which helps recover ESA-listed salmon in northern Washington. Methow Salmon views pollinators as a key part of the interconnected web that supports both salmon and communities. The foundation says using native plants is an important part of the restoration process.
As part of Pollinator Week, BPA has released its Pollinator friendly business practices implemented by BPA's fish and wildlife programreport, which is intended to help project sponsors enhance and create pollinator habitat as part of their fish and wildlife restoration projects.

What you can do to help pollinators

The USFWS offers these tips for supporting and protecting pollinators.

Plant a pollinator garden.Choose plants that flower successively throughout the growing season to provide nectar and pollen sources while pollinators are active.

  • Plant in clumps, rather than single plants, to better attract pollinators and help pollinators conserve their resources.
  • Provide a variety of flower colors and shapes to attract different pollinators. These guides for BPA's service territory provide information on the types of flowers that different pollinator groups (bats, hummingbirds, bees, butterflies, etc.) find attractive: Cascade mixed forest, intermountain semi-desert, and Selecting Plants for Pollinators.
  • Whenever possible, choose native plants because they are more beneficial to native pollinators since they coevolved. They will attract more native pollinators and some serve as host plants for some species of pollinators. Check field guides to find out which plants are used by local butterflies.
  • If monarch butterflieslive within your area, consider planting native milkweed so their caterpillars have food. Find a list of milkweed appropriate for your area.Plant other native flowering species near the milkweed so the monarchs have a food source.

Provide pollinator nesting sites. Different pollinators have different needs for nesting sites.

  • Hummingbirds typically nest in trees or shrubs and use plant materials, mosses, lichens, and spider webs to construct their nests. Their nests are very hard to find because they are typically tiny, located well off the ground, and are camouflaged to protect from predators.
  • Many butterflies lay eggs on specific host plants that their young caterpillars eat. For example, monarch butterflies lay their eggs on milkweed plants. You can find out more about the plants butterflies use by searching on the butterfly species of interest. Many of our native shrubs host butterfly species.
  • Most bees nest in the ground and in wood or dry plant stems. Many bees are solitary nesters, except bumble bees and non-native honeybees. Bumble bees have been found nesting in holes in the ground abandoned by small mammals, in openings in stone walls, in abandoned bird boxes, and other cavities. You can provide nesting sites for native bees in the following ways:
  • Ground nesting sites: Simply maintaining a small, undisturbed patch of well-drained bare or sparsely vegetated ground may provide nesting habitat for ground-nesting bees. It is best if the site faces south so that it gets the most sun possible during the day. Avoid inundating the bare ground when watering. Avoid using ground cloth and do not disturb areas where bees are seen near the ground.
  • Wood nesting sites: Carpenter bees will chew their own burrows in wood, while many other bees use holes or cavities that are already in wood or hollow plant stems.
  • Some bees will nest in artificial nesting sites - blocks of preservative-free wood drilled with holes of different diameters. Read this USDA articlefor information on how to build one.

Avoid herbicide and pesticide use during the time of year when pollinators are active. Pesticides can kill more than the target pest or weed. Some residues can kill pollinators for several days after the pesticide or herbicide is applied. Pesticides can also kill natural predators of garden pests, such as ladybugs, which can lead to even worse pest problems.

Consider the following when managing pests in your garden:

  • Buy organic seeds and plant starts whenever possible. Avoid plants that have been treated with neonicotinoids, and if you unsure about whether the plants have been treated, don't purchase them.
  • Create a diverse garden habitat, rather than monocultures, to resist pest invasion.
  • Intercrop susceptible garden plants like broccoli or cabbages with herbs that tend to repel pests such as thyme, sage, lavender and rosemary.
  • Try removing individual pests by hand if possible (wearing garden gloves) or by knocking them off the plant with a water spray (neem oil could also harm pollinators).
Accept some pests in the gardens and consider them food for songbirds and other wildlife.