We present continuous estimates of snow and firn density, layer depth and accumulation from a multi-channel, multi-offset, ground-penetrating radar traverse. Our method uses the electromagnetic velocity, estimated from waveform travel-times measured at common-midpoints between sources and receivers. Previously, common-midpoint radar experiments on ice sheets have been limited to point observations. We completed radar velocity analysis in the upper ~2 m to estimate the surface and average snow density of the Greenland Ice Sheet. We parameterized the Herron and Langway (1980) firn density and age model using the radar-derived snow density, radar-derived surface mass balance (2015–2017) and reanalysis-derived temperature data. We applied structure-oriented filtering to the radar image along constant age horizons and increased the depth at which horizons could be reliably interpreted. We reconstructed the historical instantaneous surface mass balance, which we averaged into annual and multidecadal products along a 78 km traverse for the period 1984–2017. We found good agreement between our physically constrained parameterization and a firn core collected from the dry snow accumulation zone, and gained insights into the spatial correlation of surface snow density.

An outbreak of respiratory diphtheria occurred in two health districts in the province of KwaZulu-Natal in South Africa in 2015. A multidisciplinary outbreak response team was involved in the investigation and management of the outbreak. Fifteen cases of diphtheria were identified, with ages ranging from 4 to 41 years. Of the 12 cases that were under the age of 18 years, 9 (75%) were not fully immunized for diphtheria. The case fatality was 27%. Ninety-three household contacts, 981 school or work contacts and 595 healthcare worker contacts were identified and given prophylaxis against Corynebacterium diphtheriae infection. A targeted vaccination campaign for children aged 6–15 years was carried out at schools in the two districts. The outbreak highlighted the need to improve diphtheria vaccination coverage in the province and to investigate the feasibility of offering diphtheria vaccines to healthcare workers.

Declining availability of prey is potentially a major factor limiting snow leopard Panthera uncia populations in Tajikistan and neighbouring states. Conservation initiatives to develop community-based trophy hunting programmes for ibex Capra sibirica and argali Ovis ammon polii aim to provide financial incentives for communities to limit poaching of wild ungulates. Such programmes could help to reverse local declines in ibex and argali populations, and consequently snow leopard populations, while simultaneously improving the economic status of local people. However, in practice the desired effect may not materialize. To investigate the premise, we estimated the population density of the snow leopard, using a spatial capture–recapture model based on camera trapping in two study areas (each c. 1,000 km2) in the Tajik Pamirs: a well-managed trophy hunting concession and an otherwise similar area where grazing and poaching are unmanaged. We used distance-truncated counts to assess relative densities of wild and domestic ungulates between sites, and faecal analyses to compare the dietary habits of snow leopards. Our data were limited in scope but suggested that the density of snow leopards and the relative density of wild and domestic ungulates may have been greater in the hunting concession, where wild ungulates accounted for a greater proportion of prey items. Our results provide preliminary evidence that trophy hunting of ungulates may be a viable tool for achieving snow leopard conservation goals; however, we conclude that further investigation is necessary to adequately address the question.

Continental deposits of the Early Jurassic East Berlin Formation in Holyoke, Massachusetts, have yielded an exceptional occurrence of the ichnogenus Treptichnus. Here, burrows are preserved in full relief within thin mud laminae between layers of fine-grained, cross-bedded sandstone. We studied these burrows to evaluate whether earlier explanations of burrow morphology are applicable to all Treptichnus. Our research focused on three questions. (1) Do the Holyoke Treptichnus have significant vertical relief? (2) Does the lack of projections in some of the Holyoke Treptichnus result from stratinomic sectioning through the bottom of the burrow? (3) Do expanded, bulbous ends of burrow segments result from sediment compaction? While addressing these questions, the Holyoke fossils were compared to syntype and topotype material of Treptichnus from the Carboniferous of Indiana. The Holyoke Treptichnus did not exhibit significant vertical relief, and the presence and absence of projections is explained by the positioning of new segments at different points along older ones. The bulbous ends of burrow segments resulted from trace-maker behavior, not sediment compaction. Drawing on the analysis of the Holyoke material, a new reconstruction is proposed that presents continental Treptichnus as a shallow mole-tunnel-like burrow produced just below the sediment surface. This reconstruction is consistent with the morphology of Recent Treptichnus-like burrows produced by fly (dipteran) larvae, which are considered the most likely makers of the Holyoke Treptichnus.

The availability of wild prey is a critical predictor of carnivore density. However, few conservation programmes have focused on the estimation and monitoring of wild ungulate populations and their trends, especially in the remote mountains of Central Asia. We conducted double-observer surveys to estimate the populations of ibex Capra sibirica and argali Ovis ammon in the mountainous regions of Tost Local Protected Area, South Gobi province, Mongolia, which is being considered for designation as a Nature Reserve. We also conducted demographic surveys of the more abundant ibex to examine their sex-ratio and the survival of young during 2012–2013. The estimated ibex population remained stable in 2012 and 2013 and the estimated argali population increased from 108 in 2012 to 230 in 2013. The biomass of wild ungulates was c. 6% that of livestock. Mortality in young ibex appeared to increase after weaning, at the age of 12 months. We estimated the population of wild ungulates was sufficient to support 14–18 adult snow leopards Panthera uncia. The adult snow leopard population in our study area during 2012–2013, estimated independently using camera-trap-based mark–recapture methods, was 12–14. Based on our results we identify the Tost Local Protected Area as an important habitat for the conservation of these ungulates and their predator, the Endangered snow leopard, and recommend elevation of its status to a Nature Reserve.