Assessing the global prevalence of wild birds in trade

Donald, P. F.; Fernando, E.; Brown, L.; Busana, M.; Butchart, S. H.; Chng, S.; de la Colina, A.; Machado Ferreira, J.; Jain, A.; Jones, V. R.; Lapido, R.; Malsch, K.; McDougall, A.; Muccio, C.; Nguyen, D.; Outhwaite, W.; Petrovan, S. O.; Sutherland, W. J.; Stafford, C.; Tallowin, O.; Safford, R.

doi:10.1101/2023.08.09.552606

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bioRxiv · 10.1101/2023.08.09.552606

Assessing the global prevalence of wild birds in trade

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Abstract

Trade represents a significant threat to many wild species and is often clandestine and poorly monitored. Information on which species are most prevalent in trade, and potentially threatened by it, therefore remains fragmentary. We mobilised seven global datasets on birds in trade to identify the species or groups of species that might be at particular risk. These datasets sample different parts of the broad trade spectrum but we nevertheless find a statistically strong congruence between them in which species are recorded in trade. Furthermore, the frequency with which species are recorded within datasets is positively correlated with their occurrence across datasets. This allows us to propose a trade prevalence score that can be applied to all bird species globally. This score discriminates well between species known from semi-independent assessments to be heavily or unsustainably traded and all other species. Globally, 45.1% of all bird species, and 36.7% of globally threatened bird species, were recorded in at least one of the seven datasets. Species listed in Appendices I or II of CITES, species with large geographical distributions and non-songbirds had higher trade prevalence scores. Speciose orders with high mean trade prevalence scores include the Falconiformes, Psittaciformes, Accipitriformes, Anseriformes, Bucerotiformes and Strigiformes. Despite their low mean prevalence score, Passeriformes accounted for the highest overall number of traded species of any order but had low representation in CITES Appendices. Geographical hotspots where large numbers of traded species co-occur differed between songbirds (South-East Asia and Eurasia) and non-songbirds (central South America, sub-Saharan Africa and India). This first attempt to quantify and map the relative prevalence in trade of all bird species globally can be used to identify species and groups of species which may be at particular risk of harm from trade and can inform conservation and policy interventions to reduce its adverse impacts. Article impact statementThe first metric to estimate the prevalence in trade of all the worlds bird species is presented.

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Donald, P. F., Fernando, E., Brown, L., Busana, M., Butchart, S. H., Chng, S., de la Colina, A., Machado Ferreira, J., Jain, A., Jones, V. R., Lapido, R., Malsch, K., McDougall, A., Muccio, C., Nguyen, D., Outhwaite, W., Petrovan, S. O., Sutherland, W. J., Stafford, C., Tallowin, O., Safford, R.. 2023-08-12. Assessing the global prevalence of wild birds in trade. https://doi.org/10.1101/2023.08.09.552606

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