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Summary Nitrous oxide (N2O) is a potent, globally important, greenhouse gas, predominantly released from agricultural soils during nitrogen (N) cycling. Arbuscular mycorrhizal fungi (AMF) form a mutualistic symbiosis with two‐thirds of land plants, providing phosphorus and/or N in exchange for carbon. As AMF acquire N, it was hypothesized that AMF hyphae may reduce N2O production. AMF hyphae were either allowed (AMF) or prevented (nonAMF) access to a compartment containing an organic matter and soil patch in two independent microcosm experiments. Compartment and patch N2O production was measured both before and after addition of ammonium and nitrate.In both experiments, N2O production decreased when AMF hyphae were present before inorganic N addition. In the presence of AMF hyphae, N2O production remained low following ammonium application, but increased in the nonAMF controls. By contrast, negligible N2O was produced following nitrate application to either AMF treatment.Thus, the main N2O source in this system appeared to be via nitrification, and the production of N2O was reduced in the presence of AMF hyphae. It is hypothesized that AMF hyphae may be outcompeting slow‐growing nitrifiers for ammonium. This has significant global implications for our understanding of soil N cycling pathways and N2O production.

Bait‐delivered pharmaceuticals, increasingly used to manage populations of wild boar (Sus scrofa) and feral pigs, may be ingested by nontarget species. Species‐specificity could be achieved through a delivery system. We designed the BOSTM (Boar‐Operated‐System) as a device to deliver baits to wild pigs. The BOSTM consists of a metal pole onto which a round perforated base is attached. A metal cone with a wide rim slides up and down the pole and fully encloses the base onto which the baits are placed. We conducted a pilot, captive trial and found that captive wild boar fed from the BOSTM either directly, by lifting the cone, or indirectly, by feeding once another animal had lifted the cone. Thus, we tested whether free‐living wild boar fed from the BOSTM and whether the BOSTM could prevent bait uptake by nontarget species. We observed that free‐living wild boar fed regularly from the BOSTM and that the device successfully prevented bait uptake by nontarget species. The BOSTM should be trialed more extensively to confirm its effectiveness and species‐specificity to distribute pharmaceuticals to wild suids. If successful, the BOSTM could be used to deliver vaccines in disease control programs as well as contraceptives to manage overabundant populations of wild suids.

Worldwide, wild boar (Sus scrofa) and feral pigs are involved in environmental damage and\ud disease transmission. These impacts are often associated with relatively high local densities of pigs, so the\ud monitoring of population trends is important. Dung counts can be used to estimate population trends, but\ud knowledge of daily defecation rates (DDRs) is needed to estimate absolute numbers. To address this issue, we\ud calculated the DDRs of 18 captive, adult wild boar in July 2005 and November 2007. The mean DDR was\ud 3.8–4.3 dung/boar/day, depending on the trial. We discuss the results by comparing the DDR of wild boar to\ud that of other ungulates and omnivores, and we consider the implications of these results for estimating feral\ud pig and wild boar density through dung counts

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