Abstract.  1. Aquatic macro‐invertebrates have frequently been used as biological indicators in lotic environments but much less commonly so in lentic habitats. Dragonflies and damselflies (Order Odonata) satisfy most selection criteria for lentic bioindicators of grazing impacts.2. Intensive cattle grazing affects most of the Canadian prairie pothole region but the effects of grazing on wetlands are poorly understood.3. Here the vegetation structure and invertebrate community composition of 27 prairie potholes in Alberta, Canada were studied and compared. Wetlands were evenly divided into three treatments of different grazing regimes.4. Removal of emergent vegetation by cattle grazing decreased odonate abundance and reproductive effort. Shorter Scirpus acutus stems resulted in significantly fewer damselflies (Suborder Zygoptera) and lower reproductive efforts.5. Overall odonate diversity was affected by the height of key plant species, highlighting the importance of the vegetation structure of both emergent vegetation for breeding and adjacent upland vegetation for nocturnal roosts. Wetland vegetation structure was more important than vegetation composition to the life history of odonates.6. Wetland water quality parameters of nitrogen, phosphorus, total dissolved solids (TDS), and chlorophyll‐a concentration did not change due to the presence of grazing cattle at wetlands so water quality influences were rejected as mechanisms of change.7. Larval odonate diversity and abundance was positively correlated with overall aquatic macro‐invertebrate diversity and abundance, hence it was concluded that the larval odonate community can be an accurate bioindicator of intactness and diversity of overall aquatic macro‐invertebrate communities in Canadian prairie wetlands.

Many jurisdictions in North America use a ''mitigation sequence'' to protect wetlands: First, avoid impacts; second, minimize unavoidable impacts; and third, compensate for irreducible impacts through the use of wetland restoration, enhancement, creation, or protection. Despite the continued reliance on this sequence in wetland decision-making, there is broad agreement among scholars, scientists, policymakers, regulators, and the regulated community that the first and most important step in the mitigation sequence, avoidance, is ignored more often than it is implemented. This paper draws on literature published between 1989 and 2010, as well as 33 semi-structured, key-informant interviews carried out in 2009 and 2010 with actors intimately involved with wetland policy in Alberta, Canada, to address key reasons why ''avoidance'' as a policy directive is seldom effective. Five key factors emerged from the literature, and were supported by interview data, as being central to the failure of decision-makers to prioritize wetland avoidance and minimization above compensation in the mitigation sequence: (1) a lack of agreement on what constitutes avoidance; (2) current approaches to landuse planning do not identify high-priority wetlands in advance of development; (3) wetlands are economically undervalued; (4) there is a ''techno-arrogance'' associated with wetland creation and restoration that results in increased wetland loss, and; (5) compensation requirements are inadequately enforced. Largely untested but proactive ways to re-institute avoidance as a workable option in wetland management include: watershed-based planning; comprehensive economic and social valuation of wetlands; and long-term citizen-based monitoring schemes.

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Watercourse‐crossing structures are ubiquitous anthropogenic features in the Rocky Mountain foothills of Alberta. We performed physical and habitat assessments at 295 watercourse‐crossing sites in 15 subbasins of the Athabasca River during the summer and early fall of 2007, 2008, and 2009, sampling for fish at 110 sites (32 bridges and 78 culverts). We used bootstrapping analysis to examine how several culvert parameters (hang height, outlet plunge pool depth, water velocity, length, and slope) altered the upstream abundances of eight fish species relative to those at reference bridge sites. Physical drops at the outlet (hang heights), slope, and outlet water velocities were the most important culvert parameters shaping non‐sport‐fish distributions. Some culvert types (e.g., hanging culverts) acted as complete barriers to burbot Lota lota and partially impeded the movements of spoonhead sculpin Cottus ricei, suckers Catostomus spp., and minnows (family Cyprinidae). For example, at culverts with high outlet water velocities (>0.59 m/s), the upstream proportion of the total catch for burbot was 0.32 units lower than that at bridge crossings. We did not find evidence that culverts acted as barriers to the upstream passage of rainbow trout Oncorhynchus mykiss; rather, the abundances of rainbow trout significantly increased upstream of the highest‐hanging, steepest, and longest culverts. One explanation may be that culverts that exclude burbot, a voracious predator, offer a competitive release for rainbow trout upstream of culverts. However, culverts had significantly higher water temperatures and silt and sand substrates upstream (versus downstream), whereas instream habitat did not differ at bridges. Given the large number of culverts that may be barriers in the Alberta foothills, our research emphasizes the need to better understand how species respond to the characteristics of culverts. Such data are needed to assist with making informed regulatory and planning decisions.Received March 26, 2011; accepted January 19, 2012

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SummaryWetlands in India supply crucial human and animal needs such as drinking water, protein production, fodder, water purification, wildlife habitat, and flood storage. Increased appreciation of uses and threats is essential to protect wetlands where justified. Three quarters of India's population is rural, it places great demands on India's wetlands and losses continue to occur. This paper is based on extensive discussions with natural resource managers, government employees, farmers, academicians, and resource users at dozens of sites in India, as well as an extensive literature search. Twelve important kinds of wetland loss are identified and mechanisms believed to be causing them discussed: (1) agricultural conversion, (2) direct deforestation, (3) hydrologie alteration, (4) inundation, (5) defoliation, (6) altered upper watersheds, (7) accumulative water demands, (8) water quality degradation, (9) wetland consolidation, (10) global climate change, (11) ground-water depletion, (12) exotic species and biodiversity. Wetland understanding, management, and Public awareness in India must continue growing if wetland resources are to remain functional.

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