Large herbivorous mammals play an important role in structuring African savannahs and are undergoing widespread population declines and local extinctions, with the largest species being the most vulnerable. The impact of these declines on key ecological processes hinges on the degree of functional redundancy within large-herbivore assemblages, a subject that has received little study. We experimentally quantified the effects of three browser species (elephant, impala and dik-dik) on individual-and population-level attributes of Solanum campylacanthum (Solanum incanum sensu lato), an encroaching woody shrub, using semi-permeable exclosures that selectively removed different-sized herbivores. After nearly 5 years, shrub abundance was lowest where all browser species were present and increased with each successive species deletion. Different browsers ate the same plant species in different ways, thereby exerting distinct suites of direct and indirect effects on plant performance and density. Not all of these effects were negative: elephants and impala also dispersed viable seeds and indirectly reduced seed predation by rodents and insects. We integrated these diffuse positive effects with the direct negative effects of folivory using a simple population model, which reinforced the conclusion that different browsers have complementary net effects on plant populations, and further suggested that under some conditions, these net effects may even differ in direction.

Pitfall traps are commonly used in diet studies for insectivorous and omnivorous wildlife. Pitfall trap methodologies and designs vary considerably among studies and investigators. Such variation and lack of standardization limits scientists' abilities to compare their results with others. We conducted a literature review to identify the most common methods used by past investigators who placed pitfall traps for the purpose of quantifying indices of arthropod abundances, and used this information to guide our proposal for standardized pitfall trapping methods. We documented the pitfall-trap methods of 257 studies published between January 1994 and March 2016 in 107 scientific journals. Pitfall-trap methods varied greatly across the time period. We found only minor differences in the pitfall-trap methods most commonly used in different vegetation communities (e.g., preservative was used less frequently for pitfall trap studies in grasslands). Studies published in wildlife journals tended to use pitfall traps of larger diameters than studies published in other disciplines; these studies also had worse rates of methodological reporting than those in entomology journals. We did not detect a decline in negligent reporting over time; !1 key methodological detail was missing from >50% of studies regardless of the decade published. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

There are 13 files that provide location, rainfall, habitat, vegetation, and animal data from the UHURU experiment. There are several column headings that identify the scale and location of sampling, appearing in many of the 13 datasets that follow.

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