Adaptive wetland management in an uncertain and changing arid environment

Abstract

ABSTRACT. Wetlands in the arid western United States provide rare and critical migratory bird habitat and constitute a critical nexus within larger social-ecological systems (SES) where multiple changing land-use and water-use patterns meet. The Bear River Migratory Bird Refuge in Utah, USA, presents a case study of the ways that wetland managers have created adaptive management strategies that are responsive to the social and hydrological conditions of the agriculture-dominated SES within which they are located. Managers have acquired water rights and constructed infrastructure while cultivating collaborative relationships with other water users to increase the adaptive capacity of the region and decrease conflict. Historically, water management involved diversion and impoundment of water within wetland units timed around patterns of agricultural water needs. In the last 20 years, managers have learned from flood and drought events and developed a long-term adaptive management plan that specifies alternative management actions managers can choose each year based on habitat needs and projected water supply. Each alternative includes habitat goals and target wetland water depth. However, wetland management adapted to agricultural return-flow availability may prove insufficient as population growth and climate change alter patterns of land and water use. Future management will likely depend more on negotiation, collaboration, and learning from social developments within the SES than strictly focusing on water management within refuge boundaries. To face this problem, managers have worked to be included in negotiations with regional water users, a strategy that may prove instructive for other wetland managers in agriculture-dominated watersheds.

Invasive Phragmites australis management outcomes and native plant recovery are context dependent

“…Our aim was to select sites that represented a gradient in environmental conditions in order to assess the influence of a wide range of environmental factors that are common in inland wetlands, particularly variability in hydrology, salinity, and nutrient enrichment. Hydrologic conditions ranged from drought prone, to hydrologically managed wetlands with consistent flooding (man‐made impoundments are a very common tool in arid wetlands for mitigating water scarcity), to unaltered hydrology with a typical spring peak but persistent moisture through summer (Downard, Endter‐Wada, & Kettenring, ; Long et al, ). Nutrient conditions ranged from wetlands with known eutrophic water sources to more isolated wetlands with fewer sources of nutrient enrichment (Table ).…”

Life on the edge: reproductive mode and rate of invasive Phragmites australis patch expansion

“…The [30,000 ha BRMBR consists of 26 wetland units, constructed following the 1980s flooding . These units are managed to capture water during spring snowmelt buffering wetlands from extreme drops in water levels during the agricultural growing season, when much of the Bear River is diverted, and to maintain water levels for a diversity of priority waterbird species (Olson et al 2004;Downard and Endter-Wada 2013;Welsh et al 2013;Downard et al 2014). All sampling occurred in BRMBR units 3A, 2D, 3D, and 3C ( Fig.…”

Fine‐scale genetic diversity and landscape‐scale genetic structuring in three foundational bulrush species: implications for wetland revegetation

“…). These emergent wetlands are freshwater to brackish and have dynamic water levels with spring flooding (often due to snowmelt) and declining water levels over the growing season due to a reduction in inflows (less snowmelt; diversions for agriculture) and increasing temperatures driving higher evapotranspiration rates (IWJV ; Downard et al , ). We compared our results to the patterns in Bolboschoenus (formerly Schoenoplectus ) maritimus described by Sweetman et al () for many of the same sites (with new analyses of B. maritimus data presented here, see below).…”

“…Substantial Great Salt Lake wetland loss (approximately 30%) and degradation has occurred since European settlement due to increasing diversions of freshwater sources that supply these wetlands, eutrophication from nearby (sub)urban areas, and the recent invasion (around the 1990s) of Phragmites australis (Kettenring et al ; Downard et al ). Foundational native plants are not readily returning in restoration sites following the control of P. australis , and the active reintroduction of these species is being undertaken by wetland managers (Long et al ; Rohal et al , ).…”