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Conservation initiatives overwhelmingly focus on terrestrial biodiversity, and little is known about the freshwater cobenefits of terrestrial conservation actions. We sampled more than 1500 terrestrial and freshwater species in the Amazon and simulated conservation for species from both realms. Prioritizations based on terrestrial species yielded on average just 22% of the freshwater benefits achieved through freshwater-focused conservation. However, by using integrated cross-realm planning, freshwater benefits could be increased by up to 600% for a 1% reduction in terrestrial benefits. Where freshwater biodiversity data are unavailable but aquatic connectivity is accounted for, freshwater benefits could still be doubled for negligible losses of terrestrial coverage. Conservation actions are urgently needed to improve the status of freshwater species globally. Our results suggest that such gains can be achieved without compromising terrestrial conservation goals., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

In freshwater systems, the abundance and diversity of long-distance migratory fish are limited by the maintenance of longitudinal connectivity and natural flow regimes of rivers. Using a graph-based view of each riverscape, we analyzed the river fragmentation process and overlapped with the probable number of migratory species in each remaining stretch. Applying this methodology in basins, we assess historical and potential scenarios quantifying segment extensions free from dams determining the fish richness based on the available habitat for each species. The highest number of migratory species was observed in fragments longer than 100 km. In the future scenario, there was an increase in the number of fragments, with an increase in the number of stretches shorter than 50 km, inadequate to maintain most of the migratory species. Segments of the highest classification order and located in the longest lotic fragments were considered the most important for the species habitat conservation. Dam construction in these segments could seriously affect the ecological processes at a regional level. The proposed analyses enable to approach basins with high diversity of species and nonsalmonid species, supporting the lack of base data concerning those areas, and determine priorities for studies and conservation.

Science has a critical role to play in guiding more sustainable development trajectories. Here, we present the Sustainable Amazon Network (Rede Amazônia Sustentável, RAS): a multidisciplinary research initiative involving more than 30 partner organizations working to assess both social and ecological dimensions of land-use sustainability in eastern Brazilian Amazonia. The research approach adopted by RAS offers three advantages for addressing land-use sustainability problems: (i) the collection of synchronized and co-located ecological and socioeconomic data across broad gradients of past and present human use; (ii) a nested sampling design to aid comparison of ecological and socioeconomic conditions associated with different land uses across local, landscape and regional scales; and (iii) a strong engagement with a wide variety of actors and non-research institutions. Here, we elaborate on these key features, and identify the ways in which RAS can help in highlighting those problems in most urgent need of attention, and in guiding improvements in land-use sustainability in Amazonia and elsewhere in the tropics. We also discuss some of the practical lessons, limitations and realities faced during the development of the RAS initiative so far.

The decline in stocks of commercial fish species has been documented in several regions of the world. This decline is due partially to the effect of evolutionary pressure caused by the management of fishing activity, which reduces the size of fish after a few generations. In this paper, the population dynamics of the Pintado Pseudoplatystoma corruscans, one of the main commercial species of freshwater fish in Brazil, were simulated considering different scenarios of fishing mortality and different minimum and maximum lengths of capture. The results show that selective fishing based on the different proposed selectivity curves can result in an evolution-mediated increase in the growth rate of the fish, the biomass and the catch. This suggests that appropriate changes in Brazilian legislation can contribute to the sustainability of fisheries and to conservation of the fish stocks exploited by man., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)