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Understanding both the distribution and habitat use of populations through the annual cycle is vital to understanding how vulnerable species are to environmental change. However, distributions and habitat use can vary among individuals and populations, particularly in generalist species, with variation depending on external environmental factors, such as resource availability. Comprehensive information across multiple populations is important to guide spatial planning of protected areas and is increasingly available for breeding individuals, but it is still lacking for many species, particularly seabirds, during the non-breeding season, especially those with declining populations. We investigated within-species variation in migratory strategies, non-breeding habitat selection and habitat and spatial specialisation in a declining, opportunistic, generalist seabird, the European herring gull Larus argentatus, from multiple breeding colonies across northwest England and southwest Scotland using global positioning system (GPS) tracking during the non-breeding season of 2014/15. Although several individuals stayed within the area of the breeding colony, the majority of individuals migrated in a southerly direction and spent half of the annual cycle (on average 53%) away from the breeding area and kept moving through the non-breeding period. During non-breeding, herring gulls selected mainly marine intertidal, but also a range of anthropogenic terrestrial habitats. However, habitat selection differed between geographical regions, within a geographical region and among individuals. There was a generalist use of non-breeding habitats at the population level, but some habitat specialisation at the individual level that was repeatable through the non-breeding period despite individuals showing low spatial specialisation. The results highlight the importance of intertidal habitat and a mix of alternative foraging habitats in the wintering areas of herring gulls. The results also highlight that habitat selection in an opportunistic generalist can vary even between nearby regions and that appropriate conservation management plans may need to be tailored to regional differences in specific non-breeding areas.

The spoon-billed sandpiper Calidris pygmaea, a migratory arctic-breeding shorebird, is one of the world’s rarest birds and its population has undergone a large decline in recent decades. We conducted surveys at its most important known wintering area in the Upper Gulf of Mottama in Myanmar to estimate recent (2009 – 2016) changes in its numbers there. The total number of small shorebirds present in the Upper Gulf was counted and the proportion of them that were spoon-billed sandpipers was estimated from sample scans. These two quantities were multiplied together to give the estimated number of spoon-billed sandpipers in each of four years. Total numbers of combined small shorebird species tripled from 21,000 to 63,000 between 2009 and 2016, coincident with efforts to reduce hunting pressure on waterbirds. However, the proportion of small shorebirds that were spoon-billed sandpipers declined and their estimated absolute numbers fell by about half from 244 to 112 individuals. It is probable that loss of intertidal habitat and shorebird hunting elsewhere on the migration route of the spoon-billed sandpipers wintering at Mottama is causing a continued decline, though this is occurring at a less rapid rate than that recorded from Arctic Russia before 2010. The number of spoon-billed sandpipers wintering on the Upper Gulf of Mottama remains the highest single-site total for this species from any known wintering site. Preventing any resurgence of illegal shorebird hunting and ensuring long-term protection of the intertidal feeding habitats and roost sites in the Gulf are high priorities if extinction of this species is to be averted.

Distance-specific fuel economy (FE) and emissions of carbon monoxide (CO), hydrocarbons (HC), oxides of nitrogen (NOx), and particulate matter (PM) from transit buses representing diesel, retrofitted diesel, hybrid-electric diesel, and lean-burn natural gas technologies are presented in this paper. Emissions were collected from these buses at the Washington Metropolitan Area Transport Authority (WMATA) test site in Landover, Maryland. In this program, one bus each from diesel, retrofitted diesel, hybrid-electric diesel, and natural gas technologies was tested on 17 chassis cycles and the other buses were tested on a subset of these cycles. Data show that the test cycle has a profound effect on distance-specific emissions and FE, and relative emissions performance of technology is also cycle dependant. Lean-burn natural gas buses demonstrated their low PM output, diesel engines showed low HC output, benefit of exhaust filtration was evident, and the positive effect of hybrid-electric drive technology was most pronounced for low-speed transient cycles.

In 2020, UK shooting and rural organisations pledged to achieve a voluntary transition from the use of lead shot ammunition to non-lead alternatives for hunting by 2025. The SHOT-SWITCH research project was set up in 2020 to monitor progress towards this aim by examining the proportions of wild-shot common pheasants Phasianus colchicus available to consumers in Great Britain that were killed using lead and non-lead shot. In the study’s third season, 2022/2023, 94% of pheasants sampled had been killed using lead ammunition. Statistically, this is a significantly smaller proportion than in the preceding two seasons (both > 99% lead), but it remains large. We found no direct evidence of any effect of recent voluntary initiatives to promote the replacement of lead with non-lead ammunition by suppliers and retailers of wild-shot game.

Critically Endangered Spoon-billed Sandpipers Calidris pygmaea migrate from their breeding grounds in Russia to winter on the coasts of southern China and South-east Asia. Previous studies on Leizhou Peninsula, Guangdong Province, China have shown that the species is present there in winter, as well as during the autumn and spring migration periods. However, there have been no formal estimates of the number of birds present. In November–December 2020 we conducted systematic searches for Spoon-billed Sandpipers marked individually with leg flags at Tujiao (Leizhou Peninsula) and also made scan surveys there to estimate the proportion of birds with marks. We used these data in combination to make a closed-population mark-resighting estimate of the local population in the Tujiao study area of approximately 60 individuals. Our estimate and its lower 95% confidence limit are both considerably larger than the 33 birds found during a co-ordinated count at Donghai Island, Hebei and Tujiao combined a few weeks later. This may be because raw counts tend to miss some individuals and therefore underestimate the total. The total for Tujiao represents about 8% of the estimated world population in winter, making it the second most important known wintering site after the Upper Gulf of Mottama in Myanmar.