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Throughout the world, wetlands have experienced degradation and declines in areal coverage. Fortunately, recognition of the value of wetlands has generated interest in preserving and restoring them. Post-restoration monitoring is necessary to analyze success or failure, thereby informing subsequent management decisions. Restoration of oxbow wetlands has become the focus of targeted restoration efforts to promote recovery of biodiversity and sensitive species, and to enhance ecosystem services. The fish communities of oxbows have been the subject of many monitoring studies. However, a recommended sampling methodology for monitoring the fish communities of oxbows has not been described, thereby limiting our capacity to effectively monitor these ecosystems. We compared four sampling methodologies (backpack electrofishing, fyke netting, minnow trapping, and seining) for fish community data collection with a primary objective of determining an effective method for sampling fish communities in small oxbow wetlands. Seining and fyke netting were determined to be effective methods for sampling oxbow fish communities. Backpack electrofishing and minnow trapping produced low taxonomic richness values and sampled a smaller proportion of species present than seining and fyke netting. Although seining and fyke netting produced similar taxonomic diversity and abundance values, these two gears differ in their ease of implementation and potential habitat disturbance generated by sampling. Therefore, consideration must be given to how species present (especially sensitive species) within the wetland could be impacted by sampling disturbance when choosing between seining and fyke netting. [ABSTRACT FROM AUTHOR]

Within the Great Plains region of North America, oxbow wetlands were lost as streams were channelized and straightened to allow for agricultural use of the landscape. Topeka Shiner, which rely on these oxbow wetlands, have declined in abundance, currently occupy 20% of their historical geographic range, and are now an endangered species. A large emphasis has been placed on restoring oxbow wetlands to recover Topeka Shiner populations. As the number of oxbow restorations has increased, so has the number of monitoring projects focused on these habitats. Currently, conservation practitioners rely on the presence of Topeka Shiner to determine the success of an oxbow restoration. Given the rarity of the species, this method is likely ineffective. Within this study we attempt to create a model that can be used to determine the success of an oxbow restoration that will benefit the Topeka Shiner without relying on the presence of the species in the wetland. We used multiple fish community metrics and modelling strategies to determine the best model for predicting Topeka Shiner CPUE and presence/absence within oxbows. We determined that the top models were ineffective at predicting Topeka Shiner CPUE and presence/absence. Our findings illustrate the random nature by which fish communities become established within oxbows, and the island-like nature of oxbows in terms of how fish communities may become established and change over time. These findings indicate that the success of oxbow restoration for Topeka Shiner needs to be defined at a larger scale than for individual oxbows. Furthermore, our findings corroborate the inability of previous studies to determine reproducible associations of Topeka Shiner with various fish community metrics. [ABSTRACT FROM AUTHOR]

Environmental conditions influence ecological processes that shape stream community diversity and abundance. Deforestation has the potential to limit available particulate organic matter and raise stream temperatures. The degree to which tropical stream communities are impacted by these changes is likely to differ between systems, but empirical data from tropical regions are lacking. This lack of baseline data hinders conservation policy as well as efforts to better understand biogeographic and anthropogenic impacts on species' distributions. To fill this knowledge gap, we surveyed 27 sites in six previously unstudied streams across a gradient of deforestation in northwest Ecuador and assessed the degree to which localized deforestation predicted patterns of community composition of fishes. Using general linear mixed models and AICC we found that neither forest fragmentation nor canopy closure was a significant predictor of species richness and found no difference between the species richness of fragmented and continuous sites. However, forest fragmentation was a strong predictor of abundance, occurring in 31 of 31 general linear mixed models, with higher abundance in fragmented forest than in continuous forest. Of 16 species found, eight occurred at five or more sites and one (Pseudochalceus boehlkei), numbered 200 out of 627 individuals. NMDS and SIMPER analysis suggested that community composition differed between fragmented and continuous sites. P. boehlkei, Pseudopoecilia fria, and Astroblepus cf. fissidens species presented in higher abundances in deforested sites, possibly suggesting a less functionally diverse community. This pattern is consistent with neotropical streams that have experienced partial deforestation but not total degradation of habitat. [ABSTRACT FROM AUTHOR]