BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Summary Monitoring population trends is important for evaluating the effectiveness of conservation interventions. An annual aerial census of three crane species, the Grey Crowned Crane Balearica regulorum, Blue Crane Anthropoides paradiseus and Wattled Crane Bugeranus carunculatus, was performed in KwaZulu-Natal province, South Africa over the past 23 years. These crane species are listed as ‘Endangered’, ‘Vulnerable’, and ‘Vulnerable’, respectively, on the IUCN Red List. KwaZulu-Natal was chosen as a key site for monitoring as it covers an important region for cranes that has received concerted conservation effort since the 1980s. These annual surveys are conducted by Ezemvelo KwaZulu-Natal Wildlife, a provincial conservation agency, and the Endangered Wildlife Trust, a conservation non-profit organisation. We estimated crane population trends from data collected by means of standardised surveys conducted between 2003 and 2019. Results from the surveys show a steady and significant increase in the population size of all three crane species. Interventions including power line collision mitigation and engagement with landowners have been implemented in formal conservation programs to protect these cranes. Results from the annual census suggest that conservation interventions have been effective.

The Southern Bald Ibis is endemic to South Africa, Lesotho and Eswatini, occurring across high and mid- altitude mesic grasslands and has been of conservation concern in the seventies, resulting in a range of monitoring, research and conservation actions. We examine a range of data sources to determine the conservation status of this species, employing a variety of statistical and analysis pathways. We compare trends in reporting rates from Southern African Bird Atlas Projects (SABAP), examine trends in numbers of nests reported through colony monitoring, and explore contributions made to the ‘Threatened species cause’ from the BirdLasser mobile app. Using the BirdLasser data, we find the species is widely reported across the range outside of sites with known colonies and roosts, suggesting a large proportion of the population is not available for counting during the breeding season. Using insights from the SABAP data and occupancy modelling, combined with group counts from BirdLasser data, we suggest the population is likely > 10 000 individuals. None of the trend analysis statistics we used revealed a decrease in population size for the period 1987–2021. We note that certain colonies are still being abandoned, but this is now at a lower rate (< 10% of colonies). After dramatic declines from the early part of the last century, this suggests the declines are now being curtailed, and there is some evidence the species may be recolonizing lost range. However, we note that this species is being negatively impacted by loss of grasslands to alien vegetation, and will likely be negatively impacted by climate change and other developments. While it is difficult to infer causality with conservation attention, the reversal in the fortunes of the species is encouraging for those involved in the long conservation journey of this species. Continued monitoring of this charismatic species is required in addition to ongoing habitat management to ensure declines are conclusively reversed.

Summary Across South Africa, Lesotho, and Eswatini, long-term citizen science atlas data have suggested concerning declines in the population of Black Stork Ciconia nigra. Unlike the Asian and European populations, the southern African Black Stork population is described as resident and is listed as “Vulnerable” in South Africa, Lesotho, and Eswatini. Here we report on surveys of historical nesting locations across northern South Africa, finding evidence for nest site abandonment and limited evidence of recent breeding. We undertook detailed species distribution modelling within a maximum entropy framework, using occurrence records from the BirdLasser mobile app. We cross-validated the models against information in the Southern African Bird Atlas Project (SABAP2) database, highlighting Lesotho as an important potential breeding area. Additionally, we used SABAP2 to assess population trends by investigating interannual patterns in reporting rate. Comparing current reporting rates with those from SABAP1 (1987–1992), we found that there has been a dramatic decrease. We noted that a large proportion of the population occurs outside the breeding range during the breeding season, suggesting a considerable non-breeding population, especially in the extensive wildlife refuge of the Kruger National Park. The slow declines observed might be indicative of a population which is not losing many adults but is failing to recruit significant numbers of juveniles due to limited breeding. Using densities derived from transect surveys, we used predictive models to derive estimates of breeding range carrying capacity and a population estimate, which suggested declines to numbers around 600 for this subregion. Minimising disturbance at breeding sites of this cliff-nesting species and improving water quality at key population strongholds are pathways to improving the status of the species in the subregion.