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Over the last two decades, monitoring of and research into the little bustard was carried out mainly in western Europe, and has enabled the identification of important threats to the species. Detailed information on the eastern populations’ breeding and wintering grounds is, however, still scarce. Within the western range of the species, the European Common Agricultural Policy has contributed to the loss and degradation of key habitats for little bustards. Agricultural intensification is not only a significant threat to breeding areas, but also a major concern regarding food availability and vegetation cover in post-breeding habitats. Habitat suitability is further diminished by climate change, particularly in summer within the Mediterranean basin, as birds are exposed to increasingly dry weather and rising temperatures. Collision with powerlines is a major source of non-natural mortality, as is illegal killing in Iberia. Energy developments are likely to increase in the near future, namely wind farms and particularly solar farms, which will lead to further habitat loss and collisions with associated powerlines. The eastern range now holds most of the world’s little bustard population, but hunting and poaching in eastern wintering grounds may be threatening the population, as there is evidence of significant disturbance and persecution, but detailed quantification of this is lacking. Direct and indirect effects of hunting in the western range seem important enough also to deserve further attention.

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Poly(fluorene) conjugated polyelectrolyte (CPE)-di-ureasil organic-inorganic composites have been prepared using a versatile sol-gel processing method, which enables selective localisation of the CPE within the di-ureasil matrix. Introduction of the CPE during the sol-gel reaction leads to a homogeneous distribution of the CPE throughout the di-ureasil, whereas a post-synthesis solvent permeation route leads to the formation of a confined layer of the CPE at the di-ureasil surface. The CPE and the di-ureasil both function as photoactive components, contributing directly to, and enhancing the optical properties of their composite material. The bright blue photoluminescence exhibited by CPE-di-ureasils is reminiscent of the parent CPE; however the distinct contribution of the di-ureasil to the steady-state emission profile is also apparent. This is accompanied by a dramatic increase in the photoluminescence quantum yield to >50%, which is a direct consequence of the synergy between the two components. Picosecond time-correlated single photon counting measurements reveal that the di-ureasil effectively isolates the CPE chains, leading to emissive trap sites which have a high radiative probability. Moreover, intimate mixing of the CPE and the di-ureasil, coupled with their strong spectral overlap, results in efficient excitation energy transfer from the di-ureasil to these emissive traps. Given the simple, solution-based fabrication method and the structural tunability of the two components, this approach presents an efficient route to highly desirable CPE-hybrid materials whose optoelectronic properties may be enhanced and tailored for a targeted application.