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Worldwide, fishways are increasingly criticized for failing to meet conservation goals. We argue that this is largely due to the dominance of diadromous species of the Northern Hemisphere (e.g., Salmonidae) in the research that underpins the concepts and methods of fishway science and management. With highly diverse life histories, swimming abilities and spatial ecologies, most freshwater fish species do not conform to the stereotype imposed by this framework. This is leading to a global proliferation of fishways that are often unsuitable for native species. The vast majority of fish populations do not undertake extensive migrations between clearly separated critical habitats, yet the movement of individuals and the genetic information they carry is critically important for population viability. We briefly review some of the latest advances in spatial ecological modelling for dendritic networks to better define what it means to achieve effective fish passage at a barrier. Through a combination of critical habitat assessment and the modelling of metapopulations, climate change‐driven habitat shifts, and adaptive gene flow, we recommend a conceptual and methodological framework for fishway target‐setting and monitoring suitable for a wide range of species. In the process, we raise a number of issues that should contribute to the ongoing debate about fish passage research and the design and monitoring of fishways. [ABSTRACT FROM AUTHOR]

Fish attempting to move upstream through hydroelectric dams can be trapped and killed in turbines. Understanding fish movement patterns can provide useful insights for how to manage dam operations to minimize fish kill in turbines. We evaluated the movements of two migratory fish (Curimba-Prochilodus argenteus and Mandi-Pimelodus maculatus) using acoustic telemetry in the tailrace of Três Marias Dam (São Francisco River, Brazil) from 31 October 2011 to 16 February 2012. The majority of tagged fish left the tailrace in less than one week; however, some individuals returned, performing several visits to the tailrace. Mandi remained longer in the tailrace than Curimba. The number of visits was influenced by diel period, turbine and spillway discharge. Although the diel period was the only important contributor to the visits performed by Curimba, the movements of Mandi were significantly influenced by three factors. We found that whereas Curimba was predominantly diurnal, Mandi showed nocturnal habits. Additionally, visits of Mandi were significantly greater during higher turbine and spillway discharge. We discuss the implications of these results for understanding fish movements in the Três Marias Dam tailrace and their potential implications for adapting hydroelectric operations to minimize fish kills. [ABSTRACT FROM AUTHOR]

The jaguarundi Puma yagouaroundi is a small Neotropical cat that presents two main coloration phenotypes (grey/dark vs. reddish). Although these coat colour variants have been known for decades, and historically speculated to be associated with different habitats, their exact geographical distribution has never been mapped. Moreover, their association to different habitats has so far not been tested statistically, so that their ecological relevance with respect to varying environmental features remains unknown. Based on 566 location records encompassing the entire historical range of the species obtained from camera-traps, captures and skins held in scientific collections, we produced suitability models for both jaguarundi phenotypes using maximum entropy algorithms of niche modelling. The frequency of grey/dark jaguarundis is c. 80%, whereas reddish animals represent c. 20% of our overall sample set. However, there were marked differences in these frequencies across regions. Although the spatial distribution of grey/dark animals did not depart substantially from random expectations (as it encompassed the whole species range), the occurrence of the ancestral reddish form was strongly and significantly non-random. In spite of their broad distribution across multiple habitats, grey/dark animals were significantly associated with moist and dense forests, whereas reddish forms were associated with dry and open areas such as deserts and xeric landscapes. Furthermore, there were clear spatial differences in the suitability models generated for these coat colour phenotypes. We also employed the distribution models to investigate whether particular environmental predictors could explain these different distributions. Predictors related to moisture were especially influential on the differences between the grey/dark and reddish models, and demonstrate an effect of natural selection on coloration traits, suggesting that a complex interplay of different ecological processes regulates this system over evolutionary time. [ABSTRACT FROM AUTHOR]

This work is regarding the development of a novel antenna called optically controlled reconfigurable filtenna, which is based on the integration of a broadband printed antenna with a bandpass reconfigurable RF filter. The filter is designed by applying defected microstrip structure (DMS) technique and positioned in printed antenna feeding line in order to keep the same size of the original antenna. The filtenna bandwidth is optically reconfigurable by using two photoconductive silicon switches excited by CW laser at 808 nm. Numerical results rely on independent and switchable operational modes through the 2.4 and 5.1 GHz ISM bands, whereas measurements demonstrate two reconfigurable modes based on single-band/dual-band operation over the same frequency bands. The proposed device is validated by theoretical, numerical, and experimental results. [ABSTRACT FROM AUTHOR]

This study was aimed to evaluate the behaviour of eighteen clones of Hevea brasiliensis (rubber) against South American leaf blight and to study progress of the disease. The experiment was conducted in Cachoeiro de Itapemirim- ES, where 18 clones were evaluated. The experimental design was a randomized block with four replicates; each experimental unit consisted of three plants. Evaluations were performed at 15-day intervals on 30 leaflets per tree. Disease incidence was quantified and infection classified according to the stages of development and type of damage. Leaf blight occurred during the entire experimental period; however, disease intensity varied with the resistance level of the clones and the time of year. Clones FX 3864, RRIM 725, RRIM 711, IAC 300 and IAN 873 exhibited the highest resistance to leaf blight. [ABSTRACT FROM AUTHOR]