Learning from Chemical Coping Behaviors of Wildlife to Discover New Approaches for Pest Management

Abstract

Pests, such as parasites and pathogens, persist throughout time and space as threats to public health and food security. The need for novel and sustainable approaches to managing these threats are in high demand. The current approach of discovering and developing chemical treatments to manage pests is tedious, not efficient, and often outpaced by traits of resistance in pests. Here, we propose a new approach to discovering new chemical pest management solutions by observing chemical coping behaviors in wildlife. We define a chemical coping behavior as the exploitation of naturally occurring chemicals within a host's environment to manage pests. Specifically, the use of greenery in nests by avian species may provide clues to plants that can deter ectoparasites. Plants use chemical defenses to cope with their own parasites, pathogens, and herbivores, which avian hosts can exploit to combat pests in nests. A local host-pest-plant interaction was investigated to discover the potential chemical diversity and bioactivity of greenery found in nests of golden eagles (Aquila chrysaetos). We found that each plant offered unique chemicals, but that the plant species underrepresented in nests compared to availability in the landscape provided greater diversity in volatile chemicals whereas overrepresented plant species provided greater diversity in water-soluble chemicals compared to other plants. Furthermore, we tested how concentration and diversity of volatile and water-soluble chemicals in plant species found in nests of golden eagles affected the behavior of a hematophagous parasite (Cimex lectularius, the common bed bug). We found that bed bugs spent less time resting and transitioned from grooming to exploration at an increased frequency with high concentration and diversity of volatiles from plants found in nests of golden eagles. Observing the chemical coping behaviors in the wild could provide a sustainable framework for discovering diverse and robust sources of chemicals and modes of action that can used to manage pests of human concern.