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1. Urbanisation causes important losses in biodiversity and ecosystem of animals. To test whether these negative effects are preceded by unhealthy individuals in urban populations, we evaluated the effects of urbanisation on the abundance and physical condition of the dung beetle Dichotomius guaribensis, an endemic species of the Brazilian Atlantic Forest.2. We sampled beetles in nine forest fragments with different urbanisation degrees, embedded in the urban matrix of the city of João Pessoa. Besides testing the abundance in each fragment, we quantified four indicators of physical condition in males and females: body size, body mass, energetic condition, and mite load.3. Females tended to be larger, and to have less lipid mass and more mites than males. Urbanisation had no effect on beetle abundance, but it negatively affected body mass and lipid content in males, but not females, revealing different sensitivities for both sexes. Body size and mite load were not affected by urbanisation in males or females. Fragment size had no effect on beetle abundance and physical condition in both sexes, suggesting that urbanisation has a greater impact than fragment size on beetle individual condition.4. In this study, we show that individual deterioration precedes population declines in disturbed environments, and our study opens new insights into the proximate causes that leads to the loss of biodiversity and ecosystem services in urbanised regions.

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Excrement scarcity is one of the main historical factors leading dung beetles to adapt to other food resources. In the Caatinga, a seasonally tropical dry forest, harsh environmental conditions seem to restrict the availability of food resources. In this scenario, the aim of our study was to experimentally investigate the attractiveness of different potential food resources to these insects in the Caatinga. Field samplings were performed, and we tested five resources in pitfall baited traps: excrement, carrion, fruits of two species of columnar cacti, and seeds of one species of Euphorbiaceae (Jatropha mollissima (Pohl)). In a controlled setting, we tested dietary preferences of Deltochilum verruciferum Felsche by offering one or two resources simultaneously. In the field experiments, 297 dung beetles (9 species) were recovered from the traps, and D. verruciferum was the most abundant species. Carrion and excrement were the most attractive resources. Controlled dietary preference tests with D. verruciferum evidenced that these beetles used all tested food resources, excrement and carrion most pronouncedly. Our findings support copro-necrophagy as the main feeding habit of D. verruciferum, but also suggest that alternative resources might be utilized if preferred resources are scarce.

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