Evidence of drastic loss of dung beetle diversity after 25 years in an introduced Brazilian pasture

Abstract

In tropical forest ecosystems, pastures are considered a limiting environment for dung beetles, with long-term negative effects on the diversity of this group. To understand how dung beetle diversity changes over time in introduced Brazilian pastures, studies comparing different periods are needed. Here, we conducted a study sampling dung beetles during 48 consecutive weeks in 1995 and 2020–2021. We used pitfall traps baited with fresh cattle dung in the same introduced pasture located in the Cerrado-Pantanal ecotone of Brazil. Our study found that the total species richness of dung beetles decreased by 40% in 2020–2021 compared to 1995, which could negatively impact the ecological functions of the pastures. Given the importance of dung beetles for maintaining and functioning of pastures, the decline in dung beetle diversity could lead to the degradation of pasture landscapes. We advocate for management plans for livestock production in introduced pastures that include the long-term conservation of dung beetle biodiversity. These plans will ensure the continued provision of dung beetle ecological services by dung beetles over the years.