Neonicotinoid pesticides and aflatoxins contaminate grains frequently used to feed or bait wildlife. Care should be taken to reduce the risk of toxicity in wildlife through thoughtful purchase, storage and dispersal of feed.
Aflatoxin Overview
- Aspergillus (the fungi that produces aflatoxins) grows on grain due to the presence of carbohydrates.
- Aspergillus is common in the environment and grows best in warm, moist conditions.
- Aflatoxin is produced by Aspergillus fungus as a byproduct of its metabolism. Aflatoxin is highly toxic to many species of wildlife including wild turkey and white-tailed deer if they consume a high enough dose.
- Aflatoxin can cause both acute and chronic health problems including liver failure, compromised immune system, birth defects, tumors, and reduced reproduction.
- The USDA requires grain to be tested for aflatoxin and meet low levels if the grain is intended to be fed to livestock.
Aflatoxin Best Management Practices
- Consider if offering supplemental feed to wildlife is something you need to do at all. What are your objectives and can they be met without supplemental feeding?
- Consider using protein supplements rather than grain for white-tailed deer.
- Only feed grain that has been tested for aflatoxin and meets USDA approved levels for feeding to livestock. Grain sold specifically for wildlife is not necessarily tested and may contain dangerous levels of aflatoxin.
- Avoid feeding grain in warm, moist conditions. Feeding should be limited to times when temperatures are below 60° F. Feeding grain should not be conducted when rain or high humidity is expected. Feeding grain between March-October presents the highest aflatoxin risk.
- Reduce the length of time that grain is exposed by limiting the amount dispensed at any given time. The prompt removal of uneaten grain is recommended especially if it is wet and/or moldy.
- Never feed damaged grain to wildlife. Grain that has mold or is clumping should not be used as bait or feed and should be buried or burned.
- Piling grain should be avoided. Piling grain facilitates the accumulation of moisture, increasing the risk that aflatoxin production occurs in any Aspergillus that might be present on the grain. When feeding, disperse grain as much as possible. Broadcast grain when feasible.
- Use grain sorghum (e.g., milo) rather than corn as it tends to accumulate aflatoxin at a slower rate than corn.
- Clean grain feeders regularly with bleach. Avoid refilling grain without first emptying, cleaning, and fully drying feeders.
Neonicotinoid Overview
- Neonicotinoids are a group of pesticides chemically similar to nicotine. They are intended to provide protection to crops from pest insects. Seeds are coated with neonicotinoids and the pesticide is systemic as the plant grows. Neonicotinoids are also applied to plants by foliar spray or soil treatments.
- Neonicotinoids have been shown to affect non-target insects and to be related to insect declines, including beneficial insects such as honeybees. Many insects that are exposed to neonicotinoids can be consumed by insectivorous birds such as northern bobwhite, wild turkey, and various species of songbirds.
- Neonicotinoids are toxic to vertebrates including fish and birds. These pesticides can cause both acute and chronic health issues in vertebrates.
- Multiple species of birds have been shown to consume neonicotinoid treated seed. Therefore, neonicotinoids have the potential to negatively affect birds directly (through consumption of seed and plant material) and indirectly (through reduction of insects).
- The European Union restricted 3 types of neonicotinoids in 2013 and has increasingly restricted the use of these pesticides as additional scientific evidence has become available showing negative impacts to the environment. Those impacts include reduced abundance in insects (including honeybees and other pollinating species) as well as impacts to birds. A complete outdoor ban was enacted in 2018 in the EU on 3 types of neonicotinoids.
Neonicotinoid Best Management Practices
- Ask your seed and plant provider if they are selling neonicotinoid treated plants.
- Do not plant neonicotinoid treated seeds or plants or use neonicotinoid treatments in areas intended for wildlife and/or insects such as food plots, pollinator gardens, and prairie restorations.
- If using neonicotinoid treated seed for agricultural production, avoid broadcast top-sowing. Rather, drill seed into the soil to make it less available for wildlife consumption.
- Minimize neonicotinoid dust when planting treated seed by avoiding windy conditions, carefully loading seed to prevent dust from becoming airborne, and properly disposing of residual dust from seed bags.
- Minimize use of pesticides except when necessary and use non-neonicotinoid pesticides when feasible.
- Prevent pesticide drift when applying foliar spray by avoiding windy conditions.
- Promptly clean up and dispose any spilled neonicotinoid treated seed when loading planters.
- Notify local beekeepers when using neonicotinoid pesticides.