From the perspective of zoological institutions reintroduction projects offer many possibilities to link conservation and research programmes. An example of the multi‐layered and diverse contributions that zoological institutions in general and, specifically, Vienna Zoo, Austria, can make is the reintroduction of the Northern bald ibis Geronticus eremita in central Europe. The involvement of zoological institutions ranges from the provision of eggs or birds for release trials, to financial and advocacy support, including with government agencies and non‐governmental organizations. Through involvement at a steering level at the coordinative association ‘Förderverein Waldrappteam’ and as a partner in the EU LIFE+ reintroduction project, Vienna Zoo directly contributes to the shape of the reintroduction project for this Critically Endangered species, and provides much more than technical and infrastructural support. The reintroduction of the Northern bald ibis is broadly in line with the reintroduction guidelines of the International Union for Conservation of Nature. This project provides added benefits not only through its work to prevent the illegal hunting of migratory birds but also the production and dissemination of scientific research.

AimLarge and ecologically functioning steppe complexes have been lost historically across the globe, but recent land‐use changes may allow the reversal of this trend in some regions. We aimed to develop and map indicators of changing human influence using satellite imagery and historical maps, and to use these indicators to identify areas for broad‐scale steppe rewilding.LocationEurasian steppes of Kazakhstan.MethodsWe mapped decreasing human influence indicated by cropland abandonment, declining grazing pressure and rural outmigration in the steppes of northern Kazakhstan. We did this by processing ~5,500 Landsat scenes to map changes in cropland between 1990 and 2015, and by digitizing Soviet topographic maps and examining recent high‐resolution satellite imagery to assess the degree of abandonment of >2,000 settlements and >1,300 livestock stations. We combined this information into a human influence index (HI), mapped changes in HI to highlight where rewilding might take place and assessed how this affected the connectivity of steppe habitat.ResultsAcross our study area, about 6.2 million ha of cropland were abandoned (30.5%), 14% of all settlements were fully and 81% partly abandoned, and 76% of livestock stations were completely dismantled between 1990 and 2015, suggesting substantially decreasing human pressure across vast areas. This resulted in increased connectivity of steppe habitat.Main conclusionsThe steppes of Eurasia are experiencing massively declining human influence, suggesting large‐scale passive rewilding is taking place. Many of these areas are now important for the connectivity of the wider steppe landscape and can provide habitat for endangered megafauna such as the critically endangered saiga antelope. Yet, this window of opportunity may soon close, as recultivation of abandoned cropland is gaining momentum. Our aggregate human influence index captures key components of rewilding and can help to devise strategies for fostering large, connected networks of protected areas in the steppe.

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The electrical properties of n‐type Hg1−xCdxTe LPE‐layers are analysed in terms of conduction band electron conductivity and impurity band conduction. In material showing a low concentration of compensating acceptors (K < 0.45) the usual electron conduction occurs. The electron mobility is limited by impurity scattering and lattice scattering in the low and in the high temperature range, resp. High compensated n‐type layers (K > 0.88) show an additional impurity band conduction. From comparative investigations on n‐ and p‐type annealed layers it is seen, that the impurity band is formed by approximately empty donor states on the conduction band edge. The small occupation of the donor states is caused by the high concentration of compensating acceptors.