The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

Aim To review existing literature on the ability of waterbirds to spread aquatic alien and invasive species, and to assess the relevance of bird-mediated dispersal for the conservation of freshwater ecosystems.Location Global. Methods Literature Review.Results A systematic review of the literature revealed that quantitative studies investigating dispersal of alien organisms by waterbirds are rare (n = 14). Most studies citing waterbird dispersal rely on anecdotes or inferences from morphological dispersal syndromes. However, evidence from each stage of dispersal (i.e. emigration, transport and immigration) shows that waterbirds can carry alien plants and invertebrates internally and externally; transport them between water bodies at a variety of spatial scales; and deposit viable propagules in sites suited to aquatic invasive species.Main conclusions Our review suggests that waterbirds can and do act as important dispersal vectors for freshwater invasive species. Further experimental and field based research on the numbers and viability of moved alien propagules, and the roles of different species in the bird community, is needed. Furthermore, consideration of the spatially explicit manner in which birds move is imperative to understanding invasive spread. Populations of alien aquatic species in seemingly isolated wetlands can no longer be considered contained if they are able to be spread through waterbird-mediated dispersal, and containment measures must recognize such opportunities for further spread. Changing waterbird movement patterns, driven by climate and land use change, further add to the challenge of managing invasive species and offers an interesting opportunity for future research. The study of waterbird-mediated dispersal of aquatic alien invasive species provides insights not only into species invasions, but more generally into movement ecology, population ecology and biogeography.

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1. Patterns of seed dispersal are strongly influenced by disperser and propagule traits. However, the relative importance of these characteristics for dispersal outcomes is unclear. 2. We investigated differences in the potential dispersal of wetland plants between Egyptian goose (Alopochen aegyptiaca) and red-billed teal (Anas erythrorhyncha), two southern African Anatidae. The seeds of seven wetland plants with varying traits were fed to the birds and the dispersal parameters of gut passage time, recoverability and germinability of ingested seed were determined. 3. We tested the effect of disperser species and seed traits on dispersal parameters. In addition, we determined whether increased retention times lead to lower recovery and germination of ingested seed. We predicted that the seed traits of small size and increased hardness would be better at mediating the trade-off between retention time and recoverability and germination, but that this might differ between vectors. 4. The dispersal parameters varied significantly between Egyptian goose and red-billed teal. In particular, Egyptian goose had longer average and maximum retention times of seeds, but also higher recoverability. Furthermore, short seeds had significantly longer average retention time and were also recovered in the highest numbers. Short seed length potentially facilitates endozoochory by two complementary mechanisms. First, short seeds are less digestible, leading to higher recoverability. Second, due to lower digestibility, short seeds are able to survive at longer retention times to be dispersed further, similarly to hard seeds (with hardness positively correlated with seed mass). 5. Our results suggest that small seed length and hardness are optimal seed traits facilitating endozoochory in wetland plants. Dispersal parameters were also influenced by the bird species and indicate that differences in vector morphology and digestive physiology may likely have important consequences for seed dispersal. Hence, vector characteristics should be given more explicit consideration in future studies of seed dispersal in aquatic systems.