Dung beetle species introductions: when an ecosystem service provider transforms into an invasive species

Abstract

Dung beetle introduction programmes were designed to accelerate exotic livestock dung degradation and to control dung breeding pestiferous flies and livestock parasites. The introduction programmes provided exotic dung beetle species with an opportunity to cross natural barriers and spread beyond their native range. There are no reports that explain what probable adaptation mechanisms enable particular dung beetle species to be the most successful invader. Here we identify the morphological, biological, physiological, ecological and behavioural attributes of the four most widespread and successful dung beetle species in introduced areas on a global scale in relation to the assumption that these species are different from other exotic and native dung beetles. We have recognised Digitonthophagus gazella (Fabricius), Onthophagus taurus (Schreber), Euoniticellus intermedius (Reiche) and Aphodius fimetarius (Linnaeus) as the most successful invaders based on their spread, predominance, distribution range and the reports of invasion. Each of these four species has different natural history traits that increase their fitness making them successful invaders. D. gazella has high fecundity and spreading ability, can instantly locate and colonise fresh and nutritious dung, and has a broad thermal window. O. taurus has morphological plasticity, high fecundity, high brood survival rate due to bi-parenting, and is adapted to extreme thermal and moisture conditions. E. intermedius has remnant-dung feeding abilities, a wide thermal window, functioning best at upper-temperature levels, and successful breeding and survival abilities at extremely low soil moisture conditions. A. fimetarius is small-sized, has high breeding and dispersal abilities, and is adapted to lower thermal and upper moisture extremes and variable soil conditions. Discussed here are perspectives on adaptive attributes of dung beetle species that are important to consider during their selection for redistributions. We have elaborated on the fitness and success characteristics of the four species individually. Further, we recommend a prior-introduction baseline monitoring of native dung beetle assemblages so as to evaluate the future impact of exotic dung beetle introductions on the recipient ecosystem.

Low‐temperature tolerance in coprophagic beetle species (Coleoptera: Scarabaeidae): implications for ecological services

“…Specimens were collected at night up to before sunrise (nocturnal species), an hour after sunrise and an hour before darkness (crepuscular species), and daytime between sunrise and sunset (diurnal species). Species were classified as diurnal or crepuscular or nocturnal if the majority of its individuals were collected in one of the specified periods (Hernández, 2002) and following published literature (see Blume, 1984;Caveney et al, 1995;de Oca & Halffter, 1995;Nyamukondiwa et al, 2018;Pokhrel et al, 2020). Beetles were placed in insulated cooler boxes containing moist soil and dung for feeding during transportation to the laboratory.…”

Synergistic effects of elevated temperature with pesticides on reproduction, development and survival of dung beetles

“…Larval development lasts 28 days since the female makes brood balls, each consisting of an egg covered by dung. These brood balls can vary in terms of weight and size, and will provide the food resource for the developing larvae (Martínez et al, 2017;Pokhrel et al, 2020). Its reproductive strategies allow this species to establish in non-native sites (Pokhrel et al, 2020), and disperse despite the high levels of contamination with agrotoxic products registered in some regions (González-Gomez et al, 2023).…”

“…These brood balls can vary in terms of weight and size, and will provide the food resource for the developing larvae (Martínez et al, 2017;Pokhrel et al, 2020). Its reproductive strategies allow this species to establish in non-native sites (Pokhrel et al, 2020), and disperse despite the high levels of contamination with agrotoxic products registered in some regions (González-Gomez et al, 2023). This species is well known for its response to different sources of environmental stress, and it is known that its reproductive success, physiological condition, and stress tolerance are traits with plasticity in response to stressors such as contaminants in the dung and parasitism (Cruz et…”

Population structure of Phanaeus vindex (Coleoptera: Scarabaeidae) in SE Michigan

“…Such data are needed more than ever as the populations of the rainbow scarab like many other native dung beetle populations are in peril due to habitat loss and fragmentation leading to loss of connectivity ( Cardoso et al 2020 , Watling et al 2020 ), and loss of reliable food sources ( Foster et al 2020 ) driven by the intensification of agriculture ( Blayney 2004 , USDA 2016 , Clay et al 2020 ) and urbanization ( Liu et al 2016 , Simkin et al 2022 ). The resulting extinction pressure is further accelerated by climate change ( Tocco et al 2021 ) and the displacement of native by invasive dung beetle species ( Pokhrel et al 2020 ).…”