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Little is known about the current state of freshwater biodiversity in Canada, one of the countries with the greatest amount of surface waters in the world. To address this knowledge gap, we compiled a list of all available assessments of conservation status for freshwater species (over 3000 taxa) and further evaluated the overall status of six distinct taxonomic groups, focusing on organisms reliant on fresh waters (i.e., aquatic plants, invertebrates (with a focus on freshwater mussels), fishes, herpetofauna (reptiles and amphibians), birds, and mammals). Overall, 11.7% of all freshwater species of plants and animals assessed were found to be 'at risk' (i.e., listed as 'Threatened', 'Endangered', or 'Extirpated') and 17.9% identified as 'Special Concern'. We found that 37.9% of species lacked sufficient data to enable their status to be assessed. Data gaps in Canada's assessment of its freshwater species were most prevalent in invertebrates (excluding freshwater mussels). Given the alarming state of freshwater biodiversity in Canada, we conclude by providing recommendations that focus on evaluating temporal trends and informing conservation actions. Les connaissances sur l'etat actuel de la biodiversite des especes d'eau douce au Canada, un des pays disposant de la plus grande quantite d'eau de surface au monde, sont limitees. Pour examiner cette lacune, nous avons compile une liste de toutes les evaluations disponibles du statut de conservation d'especes d'eau douce (plus de 3000 taxons) et evalue en outre le statut global de six groupes taxonomiques distincts, en mettant l'accent sur les organismes dependant des eaux douces (c.-a-d., les plantes aquatiques, les invertebres (plus particulierement les mulettes), les poissons, l'herpetofaune (reptiles et amphibiens), les oiseaux et les mammiferes). Globalement, 11,7 % de toutes les especes d'eau douce de plantes et d'animaux evaluees sont << en peril >> (c.-a-d., designees << menacees >>, << en voie de disparition >> ou << disparue au pays >>) et 17,9 % ont un statut de conservation << preoccupant >>. Nous constatons que les donnees disponibles sont insuffisantes pour permettre l'evaluation du statut de 37,9 % des especes. Le groupe des invertebres (a l'exception des mulettes) est celui pour lequel la prevalence des cas de manque de donnees pour l'evaluation d'especes d'eau douce au Canada est la plus grande. Au vu de l'etat alarmant de la biodiversite des especes d'eau douce au Canada, nous concluons en formulant des recommandations qui mettent l'accent sur l'evaluation des tendances dans le temps et la production de donnees pour eclairer les mesures de conservation. [Traduit par la Redaction], 1.0. Introduction Despite occupying less than 1% of the Earth's surface, the freshwater biome is home to 12% of all described species, including as much as one third of all [...]

Protected areas are an important part of broader landscapes that are often used to preserve biodiversity or natural features. Some argue that protected areas may also help ensure provision of ecosystem services. However, the effect of protection on ecosystem services and whether protection affects the provision of ecosystem services is known only for a few services in a few types of landscapes. We sought to fill this gap by investigating the effect of watershed protection status and land use and land cover on biodiversity and the provision of ecosystem services. We compared the ecosystem services provided in and around streams in 4 watershed types: International Union for Conservation of Nature category II protected forests, unprotected forests, unprotected forests with recent timber harvesting, and unprotected areas with agriculture. We surveyed 28 streams distributed across these watershed types in Quebec, Canada, to quantify provisioning of clean water, carbon storage, recreation, wild foods, habitat quality, and terrestrial and aquatic biodiversity richness and abundance. The quantity and quality of ecosystem services and biodiversity were generally higher in sites with intact forest—whether protected or not—relative to those embedded in production landscapes with forestry or agriculture. Clean‐water provision, carbon storage, habitat quality, and tree diversity were significantly higher in and around streams surrounded by forest. Recreation, wild foods, and aquatic biodiversity did not vary among watershed types. Although some services can be provided by both protected and unprotected areas, protection status may help secure the continued supply of services sensitive to changes in land use or land cover. Our findings provide needed information about the ecosystem service and biodiversity trade‐offs and synergies that result from developing a watershed or from protecting it. Article impact statement: Streams surrounded by forest—protected or not—support more ecosystem services and biodiversity than streams in production landscapes. [ABSTRACT FROM AUTHOR]

The methylated form of mercury (methylmercury) is a potent neurotoxic chemical and a contaminant of concern for fisheries because of its potential effects on ecosystem and human health. In Africa, inland fisheries are a crucial component of food and economic security, yet little information is available on mercury (Hg) contamination trends. The authors compiled published data on Hg contamination in African freshwater fishes, invertebrates, and plankton, as well as on potential drivers of Hg concentrations in these organisms. From 30 identified studies the authors assembled 407 total Hg concentrations from 166 fish species, 10 types of invertebrates, and various plankton, distributed across 31 water bodies in 12 countries. In fishes, total Hg concentrations, expressed as mean (± standard deviation) per location, averaged 156.0 ± 328.0 ng/g wet weight and ranged from 5.5 ng/g wet weight to 1865.0 ng/g wet weight. Only locations with nearby artisanal and small-scale gold mining operations had mean Hg concentrations above the World Health Organization/Food and Agriculture Organization's recommended guideline for fish (500 ng/g wet wt). The authors used mixed models to detect relationships between fish Hg concentrations and trophic level, mass, latitude, and chlorophyll a. Mass, trophic level, and latitude were all positive predictors of Hg concentration, confirming the presence of Hg bioaccumulation and biomagnification in African fishes. Although strong trends in Hg concentrations were evident, the present study also highlights limited availability of Hg data in Africa. Environ Toxicol Chem 2014;9999:1-9. © 2014 SETAC [ABSTRACT FROM AUTHOR]