Protecting Pollinators During Pesticide Applications

For pest management professionals (PMPs), pollinators are not typically top of mind, but they should be a consideration.

Most of the conversation around pollinators occurs in the agricultural and landscaping spheres, but many of the chemistries we rely upon are used across industry lines. New regulations or label requirements placed on active ingredients can impact our work.

We can minimize any potential negative impacts to our industry if we approach this conversation as an ally rather than an adversary, and as such, we need to have some base knowledge about pollinators.

Pollinators are simply animals that are involved in pollination. Pollination is the transfer of reproductive material (pollen) from the anther of one flower to the stigma of another. Pollination is performed by a wide range of animals, including birds, bats, beetles, flies, butterflies, moths and, of course, bees.

POLLINATORS AND THE ECONOMY. Pollinators are estimated to contribute as much as $24 billion to the U.S. economy annually. Without question, honey bees provide the bulk of that value and are estimated to account for approximately $15 billion through direct pollination services, honey production and other bee-related products such as propolis and wax. Bees assist in production of nearly one-third of all food produced and are necessary for most commercially grown crops.

The presence of bees also can enhance production on crops where pollinators are not required. For example, one of my favorite drinks, coffee, comes from a self-pollinating tree. The presence of bees in coffee fields can improve yields by as much as 30 percent. That translates into 100 million cups of coffee per year in the U.S. alone.

For most people, the overly broad statement “no bees, no food” ends the conversation, but pollination is much more complex than that. Non-bee pollinators like flies and butterflies also are important. Perhaps one of the best examples of non-bee pollination is cacao, the plant that is refined into chocolate. Several species of midge flies are essential for pollinating these plants due to the small size and shape of the flower.

LEGAL OBLIGATIONS. There are too many insects and animals involved in pollination to cover in a single article, but honey bees are the primary focus of public attention, and thus regulatory efforts. The western or European honey bee (Apis mellifera) is the most common species managed by humans and is the dominant species in Europe and the Americas.

Due to their beneficial nature, bees may enjoy special legal protections in some locations. A good resource on managing bee pests and legal obligations is your state’s department of agriculture or local university extension agents.

In addition to laws, there are often requirements on pesticides intended to be used outdoors, and these typically can be found in the environmental hazards section of the label.

ALL ABOUT BEES. Bees are in the order Hymenoptera, related to ants and wasps. They are a eusocial insect living in colonies of up to 60,000. Bees employ a caste system and have complex systems of communication. They feed on the nectar that flowers produce.

During feeding, pollen from the plants sticks to the hairs on the bee and is transported from flower to flower. Bees prefer flowers that are yellow or blue and tubular shaped with a landing pad. Once a food source is located, other bees are recruited using pheromones and a “dance.” Bees typically have a range of up to 2 miles from the hive.

Bees tend to be present in the warmer parts of the day, with early afternoon being their most active time outside the hive.

Knowing what bees prefer and when they are active allows PMPs to modify their work to minimize impact on bees.

PESTICIDES AND POLLINATORS. Pesticides, specifically insecticides, are important tools in our industry. The simplest thing we can do to reduce our impact on pollinators is to address conducive conditions that attract pests, thus reducing the need for pesticides. Talking to your customers and working in partnership to eliminate these conditions will result in effective long-term pest control.

We also can change the time of day we schedule certain types of work, like mosquito prevention, to minimize our likelihood of encountering bees. Earlier in the day, bees are less active, so there is less chance of direct contact with insecticides.

As PMPs, we have a lot of control on how and where pesticides are applied. By choosing pesticides that are lower toxicity to bees and applying them in a more targeted manner, we can reduce risks to bees.

One group of chemicals, neonicotinoids, receives a lot of attention because these products are highly toxic to bees. Imidacloprid, acetamiprid, dinotefuran, thiamethoxam and clothianidin are all neonicotinoids. Products containing these active ingredients receive special labeling to alert users.

Using alternatives to these pesticides in areas where bees are more likely to be present can reduce risk. Pyrethrin insecticides are a good example of an alternative commonly used in the industry. As always, carefully read all product labeling closely. In many cases, the label prohibition is on direct contact with bees foraging in the area; however, your local regulations may require enhanced procedures.

Formulation is another consideration that can be controlled by the PMP. Because of the use pattern, granular or dust formulations present a lower risk to bees. Since granules rapidly sort to ground level, bees are unlikely to contact these insecticides. Dusts are typically only able to be applied in cracks and crevices, thus unlikely to impact bees.

Pest control services for flying insects like mosquitoes present one of our most significant risks to pollinators. To effectively prevent flying insects from entering structures, we typically treat the vegetation around the structure, as this is where flying insects rest. Conducting a visual inspection and scheduling services earlier in the day can reduce overall risks.

ENVIRONMENTAL FACTORS. As with any outdoor work, environmental considerations like rain or wind are also a factor. Drift management typically isn’t a significant concern because we mostly apply pesticides directly to or close to structures. That said, areas that are more exposed to windy conditions or very dry areas can experience pesticide drift.

Pesticide drift is simply when the pesticide residue is transported away from the site of application. The most common cause is being blown by the wind. Drift can bring your pesticides to where bees are actively foraging, causing you to commit a label violation, which can result in a potential bee kill.

Drift management requires planning, and for the purposes of a PMP is primarily achieved mechanically: Either adjust your spray pattern to have larger droplets, or bring your sprayer output closer to the target.

WHEN BEES ARE THE PEST. One other consideration: What if bees are the pest? Honey bees can infest structures, causing risks to occupants. The result is that you may be hired to eliminate the hive.

In the context of protecting pollinators, explore hive relocation. Relocation involves working with a professional beekeeper who captures the queen. The colony relocates with the queen, so in this manner we can eliminate the problem without harming the pollinator.

In this situation, arrangements must be made to remove the hive material to prevent other pest problems.

FINAL THOUGHTS. You can reduce risk to pollinators with a little thought and care. Consider adopting a formal integrated pest management (IPM) plan in your regular work.

Our business isn’t applying pesticides, it’s controlling pests. Identifying and eliminating conducive conditions, accurately identifying pests and directing control methods at the source are our most effective approaches.

You also can get involved by working with our partners in other industries. Work and communicate with local beekeeping associations, colleges, extension agents, agricultural and apiary training programs to hear their concerns and collaborate on solutions. Sometimes, it’s as simple as having a conversation.

Steve Russo, B.C.E., is the regional support manager for Terminix Hawaii. He sits on the Hawaii Pesticide Advisory Committee.