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In melissopalynological studies, the investigation of pollen composition in honey samples reveals the geographical and botanical origin of the samples and links them to the regional climatic conditions. Honeybees (Apis mellifera), collect pollen and nectar for their nutritional requirements based on the seasonal availability of surrounding flora. In this study, pollen content in honey was temporarily investigated for seasonal differences of the bee foraged plants. A melissopalynological investigation was applied to honey samples harvested from 13 beehives located in the Greater Kruger National Park, South Africa. Multivariate statistics (NMDS and Rarefaction curves) were used to show spatial and temporal clustering of the samples. The melissopalynological data were then compared to the species’ flowering season and a botanical survey of the surrounding area. The turnover in pollen composition for different seasons signifies seasonal variation in pollen types. For example, during summer, bees foraged from fewer floral sources. The highest species richness was observed during winter, suggesting a higher dependence on a diversity of floral resources during the driest months. Various seasonal pollen spectra were characterised by a pollen turnover from numerous species, including Combretum type, Sclerocarya birrea, Poaceae, Harpephyllum caffrum and Lannea schweinfurthii but also neophytes such as Medicago sativa. Therefore, honey samples from the Lowveld region in South Africa reflected the seasonal patterns of the surrounding flora although pollen from taxa such as Combretum spp. (average 56%) and Sclerocarya birrea (average 14%) were continuously sought after by bees throughout the year.

1. We review progress in our understanding of the importance of waterbirds as dispersal vectors of other organisms, and identify priorities for further research. 2. Waterbirds are excellent for long-distance dispersal (LDD), whereas other vectors such as fish and mammals disperse similar propagules, but over shorter distances. Empirical studies of internal and external transport by waterbirds have shown that the former mechanism generally is more important. Internal transport is widely recognised for aquatic plants and aquatic invertebrates with resting eggs, but also is important for other organisms (e.g., terrestrial flowering plants not dispersed by frugivores, bryophytes, tardigrades, fish eggs). 3. Waterbird vectors also are important in terrestrial habitats, and provide connectivity across terrestrial–aquatic boundaries. There are important differences in the roles of different waterbird species, especially those using different habitats along the aquatic–terrestrial gradient. Early attempts to predict zoochory based on propagule morphology have been found wanting, and more research is needed into how the traits of vectors and vectored organisms (including life history, dormancy and growth traits) explain dispersal interactions. Experimental studies have focused on the potential of propagules to survive internal or external transport, and research into factors determining the establishment success of propagules after dispersal is lacking. 4. Recent spatially explicit models of seed dispersal by waterbirds should be expanded to include invertebrate dispersal, and to compare multiple bird species in the same landscape. Network approaches have been applied to plant–waterbird dispersal interactions, and these are needed for invertebrates. Genetic studies support effective LDD of plants and invertebrates along waterbird flyways, but there remains a lack of examples at a local scale. Next Generation Sequencing and genomics should be applied to waterbird-mediated dispersal across the landscape. More studies of biogeography, community ecology, or population genetics should integrate waterbird movements at the design stage. 5. Zoochory research has paid little attention to the dispersal of non-pathogenic microbes (both eukaryotic and prokaryotic). Nevertheless, there is evidence that dispersal via avian guts can be central to the connectivity of aquatic microbial metacommunities. More work on microbial dispersal by waterbirds should explore its implications for biogeochemistry, and the interchange with gut flora of other aquatic organisms. In the Anthropocene, the role of migratory waterbirds in LDD of plants and other organisms is particularly important, for example in compensating for loss of large migratory mammals and fish, allowing native species to adjust their distributions under global warming, and spreading alien species along flyways after their initial introductions by human vectors. Recent technological advances have opened exciting opportunities that should be fully exploited to further our understanding of dispersal by waterbirds. AJG was supported by projects from the Ministerio de Ciencia e Innovación (PID2020-112774GB-I00/AEI/10.13039/501100011033) and Ministerio de Economía y Competitividad (CGL2016-76067-P). ESG received the grant RYC2019-027216-I funded by MCIN/AEI/10.13039/501100011033 and from ESF Investing in your future. GGS received a postdoctoral fellowship from CNPq (grant no. 150887/2022-1) ÁLK was supported by a János Bolyai Research Scholarship of the Hungarian Academy of Sciences, New National Excellence Programme of the Ministry of Innovation and Technology ÚNKP-21-5-DE-457, NKFIH FK-138698 grants.

Pishing is an imitated alarm call frequently used by birders and ornithologists to attract birds and provide close-up views. However, despite the widespread use of pishing in the field, data on the success of this technique are still scarce. Here we tested the effectiveness of pishing as an attracter of birds in a subtropical savanna in South Africa, using a randomised controlled trial design. Over a period of 12 months, repeated silent observation and pishing treatments were randomly applied across 30 preselected savanna sites to test the response to pishing of both the bird community and individual species. Overall, significantly more individual birds were recorded during the pishing treatment than during the silent observation control treatment. Furthermore, the observation rates of eleven species, from seven passerine families, were significantly higher during pishing treatments. Robins in the Muscicapidae were especially responsive. Pishing does increase visibility of arboreal passerines in African subtropical savanna. This finding confirms that the technique is an effective tool for increasing bird observations in the field and informs current discussions on the ethics of pishing in the South African birding community. Keywords: birds; alarm call; pishing; playback

Concentrations of organochlorine pesticides have been extensively monitored in birds, particularly from higher trophic guilds such as raptors. While monitoring of raptors has been ongoing for decades, patterns from monitoring activities have never been summarised on a global scale. In this study, we undertake a review to better describe the monitoring of two widespread organochlorine pesticides monitored globally in raptors, DDT and dieldrin. We provide a historical retrospective on the monitoring effort of a global environmental issue. Sampling was heavily biased geographically to the global north, with more than 90 % of studies conducted in this socio-geographic region, most from Europe and North America. Although monitoring occurred from at least 114 species, most samples came from relatively few species, with three species (Eurasian Sparrowhawk Accipiter nisus, Bald Eagle Haliaeetus leucocephalus, and Peregrine Falcon Falco peregrinus) comprising 50 % of samples. The types of raptors sampled have changed over time, with avian and mammal specialists dominating samples until the 1970s, but more diverse dietary guilds monitored in later decades, and greater proportions of samples coming from generalist species. The three most sampled tissues (egg, liver, and plasma) comprised 84 % of all samples. Eggs were the earliest tissue examined and the only tissue sampled in all decades. The geographical bias in monitoring effort and relatively narrow species focus, suggests that patterns in these pesticides are unlikely to be fully representative of all global environments occupied by raptors. While DDT has been banned throughout most of the global north, it remains in use in the global south, yet monitoring effort in the south, does not match that of the north. While monitoring remains prevalent in the global north, contemporary monitoring is limited in the global south with less than 10 % of raptors sampled in Asia, Africa, and South America, over the last 3 decades.