An African Dusky Flycatcher Muscicapa adusta was observed on 23 May 2024 on Robben Island, Table Bay, South Africa. This brings the total number of bird species recorded on Robben Island to 166; the number reported since 2000 is 135.

Citizen science data are rapidly transforming the conservation landscape. Targeted participatory citizen science initiatives generate nuanced data capable of monitoring trends in populations and generating early warnings for species and habitats experiencing significant declines. In the Hessequa Atlasing Area, Western Cape, South Africa, citizen science 'atlasers' involved with the Second Southern African Bird Atlas Project (SABAP2) have worked with scientific leadership since 2014 to improve the quality of bird atlas data in their region for species monitoring. In this study, we used reporting rates from SABAP2 checklists in the Hessequa Atlasing Area to calculate changes in range size and relative abundance for the 165 most commonly reported species in the region. We used a seven-tier alert system and broad habitat categories to sort species by priority for conservation action. Our results showed that wetland and marine associated species are experiencing the greatest declines in range and relative abundance in the Hessequa Atlasing Area, whilst urban and grassland associated species are largely increasing. We discuss how observed changes in populations may be used to guide conservation action and provide recommendations for scientists and non-scientific community members on engaging with and responding to the changes highlighted in each of the seven alert levels provided.

Data from five citizen science projects were used to document shifting ranges of two species of bulbul in South Africa. We show that African Red-eyed Bulbuls Pycnonotus nigricans steadily replaced Cape Bulbuls P. capensis in the lower Olifants River valley, in northern Western Cape province, South Africa. The first observations of African Red-eyed Bulbuls in this valley were recorded by atlasers in winter 2011. Bird atlas reporting rates were still steadily increasing in this region at the end of 2021. Environmental conditions seem to have been suitable for range expansion of the African Red-eyed Bulbul into the area for at least five decades before they first arrived. This is a common feature of range expansions into the Western Cape. We discuss the value of the citizen science projects. The photographic records of the Virtual Museum have the advantage that they can be verified, and we made use of the habitat features displayed in the background. The bird atlas, in contrast, is based on sight records that cannot be checked; we observed a tendency for bird atlasers, who operate with fieldwork time constraints, to record the bulbuls in the study area as Cape Bulbuls because this was the bulbul that was traditionally observed there. Les donn & eacute;es de cinq projets de science citoyenne ont & eacute;t & eacute; utilis & eacute;es pour documenter le d & eacute;placement des aires de r & eacute;partition de deux esp & egrave;ces de bulbuls en Afrique du Sud. Nous montrons que le Bulbul brunoir Pycnonotus nigricans a progressivement remplac & eacute; le Bulbul du Cap P. capensis dans la basse vall & eacute;e de la rivi & egrave;re Olifants, dans le nord de la province du Cap-Occidental, en Afrique du Sud. Les premi & egrave;res observations de Bulbul brunoir dans cette vall & eacute;e ont & eacute;t & eacute; enregistr & eacute;es par des atlas en hiver 2011. Les taux de signalement des atlas d'oiseaux & eacute;taient toujours en augmentation constante dans cette r & eacute;gion & agrave; la fin de l'ann & eacute;e 2021. Les conditions environnementales semblent avoir & eacute;t & eacute; propices & agrave; l'expansion de l'aire de r & eacute;partition du Bulbul brunoir dans la r & eacute;gion pendant au moins cinq d & eacute;cennies avant son arriv & eacute;e. Il s'agit d'une caract & eacute;ristique commune & agrave; plusieurs cas d'expansion de l'aire de r & eacute;partition dans le Cap occidental. Nous discutons de la valeur des projets de science citoyenne. Les photographies du Mus & eacute;e Virtuel ont l'avantage de pouvoir & ecirc;tre v & eacute;rifi & eacute;es, et nous avons pu utiliser les caract & eacute;ristiques de l'habitat affich & eacute;es en arri & egrave;re-plan. L'atlas des oiseaux, en revanche, est bas & eacute; sur des relev & eacute;s visuels qui ne peuvent pas & ecirc;tre v & eacute;rifi & eacute;s; nous avons observ & eacute; une tendance des observateursaux, qui travaillent avec des contraintes de temps sur le terrain, & agrave; enregistrer les bulbuls dans la zone d'& eacute;tude comme Bulbuls du Cap parce que c'est le bulbul qui a & eacute;t & eacute; traditionnellement observ & eacute; dans cette zone.

This annotated picture booklet aims to provide a quick identification guide to the common birds in Cape Town’s urban gardens. This guide covers the 32 species you are most likely to encounter; though it is not comprehensive, the species included have been carefully selected to help you make a start.

Halting biodiversity loss on land (Sustainable Development Goal [SDG] 15) is an unfolding problem, and as such, requires novel solutions. Citizen science (CS) promises large quantities of data, but introduces the challenge of ensuring these are valuable to conservation research and can inform meaningful action. This paper contributes to this endeavour, examining the impact of systematic as opposed to unstructured fieldwork on the biodiversity monitoring value of data from the Second Southern African Bird Atlas Project (SABAP2). SABAP2 “atlasers” work within a fine-scale grid system to generate avian species checklists that are comprehensive at the time of fieldwork. Though valuable, unstructured fieldwork efforts paint an incomplete picture; effective conservation action requires monitoring—keeping a finger on the pulse of local biodiversity through consistent and systematic data collection. Systematic collection allows for the detection of nuanced biological patterns such as seasonal population trends and movements, rapidly alerting scientists to anomalies and galvanizing swift response. It is, however, a demanding protocol, and implementation requires careful consideration of participant impact and motivations. Here, we used a newly developed approach for measuring temporal data quality to examine the systematic atlasing efforts of a CS community in the Hessequa Atlasing Area, South Africa, assessing the biodiversity monitoring value of structured data collection versus opportunistic checklists. We found that structured data collection increased the temporal resolution of atlas data, and thus its monitoring quality. We discuss challenges in maintaining achievable fieldwork goals for participants, and examine Hessequa’s project structure and participant motivations to provide recommendations for future project management.

Though recent research has explored the negative impact of human infrastructure on large waterbirds, few studies have examined behavioural byproducts such as roosting or nesting on transmission wires. Here, we document our observation of a joint roost of White-breasted Cormorant Phalacrocorax lucidus and African Darter Anhinga rufa on transmission lines in the Western Cape, South Africa. We highlight current gaps in understanding communal roosting, joint roosts between species, and roosting on infrastructure, and provide recommendations for future directions of study.

The individual behavioral traits of predators and prey sometimes determine the outcome of their interactions. Here, we examine whether changes to habitat complexity alter the effects of predator and prey behavior on their survival rates. Specifically, we test whether behavioral traits (activity level, boldness, and perch height) measured in predators and prey or multivariate behavioral volumes best predict the survival rates of both trophic levels in staged mesocosms with contrasting structural complexity. Behavioral volumes and hypervolumes are a composite group-level behavioral diversity metric built from the individual-level behavioral traits we measured in predators and prey. We stocked mesocosms with a host plant and groups of cannibalistic predators (n = 5 mantises/mesocosm) and their prey (n = 15 katydids/mesocosm), and mesocosms varied in the presence/absence of additional non-living climbing structures. We found that mantis survival rates were unrelated to any behavioral metric considered here, but were higher in structurally complex mesocosms. Unexpectedly, katydids were more likely to survive when mantis groups occupied larger behavioral volumes, indicating that more behaviorally diverse predator groups are less lethal. Katydid mortality was also increased when both predators and prey exhibited higher average perch heights, but this effect was increased by the addition of supplemental structure. This is consistent with the expectation that structural complexity increases the effect of intraspecific behavioral variation on prey survival rates. Collectively, these results convey that the effects of predator and prey behavior on prey survival could depend highly on the environment in which they are evaluated.