Keeping Wetlands Wet: The Human Hydrology of Wetlands in the Bear River Basin

This research seeks to understand how wetlands maintain a water supply in the Bear River Basin, where water is generally scarce. Research was conducted through semi-structured interviews with wetland and water experts in the basin and archival research of historical documents and water rights. The U. S. Fish and Wildlife Service manages three refuges on the Bear River, and has obtained water rights portfolios for each. Holding water rights does not ensure that there will be water available for refuge wetlands. Instead, position in relation to other powerful water users is the most important factor in determining the security of a refuge\u27s water supply and the threats faced from drought. All refuges must manage their water because the human-hydrology of the river is complex and variable; this requires a combination of infrastructure and planning. Maintaining relationships with other water users is another important adaptation to the human-hydrology of the river, because all water users along the river are interconnected. Recognizing that they face the same threats to their water supply allows wetland managers and irrigators to cooperate in order to maintain the water supply for their region of the river and increases adaptability as the region faces climate change. The Bear River Migratory Bird Refuge is the oldest refuge on the river and has the least secure water supply, despite having the largest water rights portfolio. Because it is chronically short of water during the summer, refuge staff have developed an adaptive management strategy to effectively utilize the water they do receive. Management involves predicting water supplies each year, setting water level targets accordingly, actively diverting water to priority wetlands, and allowing non-priority wetland to dry. This is followed by extensive monitoring of habitat conditions and bird use, the results of which are shared in annual management plans. This strategy maintains the most wildlife habitat possible and offers important institutional adaptations. Most importantly, it demonstrates the refuge\u27s water rights are being put to beneficial use. Sharing knowledge gained through management also builds trust and adaptive capacity among water users facing the complex human-hydrology at the end of the Bear River

Soils of Great Salt Lake Wetlands: Hydric Indicators and Common Features

Using information in this booklet, the physical features of a wetland soil can be observed to tell a story about a soil’s history, its characteristics, the wetland in which it is found, and the plant life it supports. Hydric soils have unique characteristics, due to anaerobic conditions, that distinguish them from other soil types. Great Salt Lake wetland soils display many of these hydric characteristics. The many functions that Great Salt Lake wetland soils provide, from transforming nutrients, to filtering toxins and accumulating loose sediments, make them an important resource worth protecting. The diversity of soil types and soil features in this re-gion both support and reflect the dynamic diversity of plants and animals that visitors admire

Wetland Plants of Great Salt Lake, A Guide to Identification, Communities, & Bird Habitat

Wetland Plants of Great Salt Lake: a guide to identification, communities, & bird habitat is a wetland plant identification guide, resulting from collaborative research efforts about Great Salt Lake (GSL) wetland conditions and bird habitat. Dr. Rebekah Downard collected dissertation field data from GSL wetlands during 2012–2015, the majority of which informed this work. Dr. Maureen Frank contributed her guide to GSL wetland vegetation and how to manage native plants as high-quality habitat for birds. The intended purpose in producing this guide was to create an informative source that could assist researchers, land managers, birders, and wetland enthusiasts in identifying, studying, managing, and understanding Great Salt Lake wetland plants, communities, and birds

Spatial and Temporal Variation in Brackish Wetland Seedbanks: Implications for Wetland Restoration Following \u3ci\u3ePhragmites\u3c/i\u3e Control

Chesapeake Bay tidal wetlands are experiencing a broad-scale, aggressive invasion by the non-native, clonal grass Phragmites australis. The grass is often managed with herbicides in efforts to restore native plant communities and wildlife habitat. Management efforts, however, can act as a disturbance, resulting in increased light availability, potentially fostering reinvasion from soil seedbanks. If native vegetation establishes quickly from seedbanks, the site should have greater resiliency against invasion, while disturbed sites where native plants do not rapidly establish may be rapidly colonized by P. australis. We surveyed the soil seedbank of three vegetation cover types in five Chesapeake Bay subestuaries: areas where P. australis had been removed, where P. australis was left intact, and with native, reference vegetation. We determined the total germination, the proportion of the seedbank that was attributable to invasive species, the richness, the functional diversity, and the overall composition of the seedbanks in each of the cover types (i.e., plots). After 2 years of herbicide treatment in the P. australis removal plots, vegetation cover type impacted the total germination or the proportion of invasive species in the seedbank. In contrast, we also found that seedbank functional composition in tidal brackish wetlands was not influenced by vegetation cover type in most cases. Instead, plots within a subestuary had similar seedbank functional composition across the years and were composed of diverse functional groups. Based on these findings, we conclude that plant community recovery following P. australis removal is not seed-limited, and any lack of native vegetation recruitment is likely the result of yet-to-be-determined abiotic factors. These diverse seedbanks could lead to resilient wetland communities that could resist invasions. However, due to the prevalence of undesirable species in the seedbank, passive revegetation following invasive plant removal may speed up their re-establishment. The need for active revegetation will need to be assessed on a case-by-case basis to ensure restoration goals are achieved

Assessing the ecological condition of emergent wetlands in a hydrologically dynamic, ecologically unique and extensively managed system - the Great Salt Lake, Utah

The hydrology of the rivers that supply the Great Salt Lake (GSL) and associated wetlands has been significantly altered for irrigated agriculture and urban development. Many of the wetlands that rely on these rivers have been impounded to maintain as much migratory bird habitat as possible, in the face of these hydrologic changes. However, while the discharge of rivers and the elevation of the GSL are well known, the hydrology of the emergent wetlands that lie between is unknown. Further, the impact of impoundment and water management on wetland function is also unknown, despite the critical habitat, flood buffering, and water quality improvement functions these wetlands perform. GSL wetlands are ecologically unique and require a regionally specific wetland assessment method that recognizes natural variability in salinity, an overall lack of species richness, and that is impoundment is an intentional management tool rather than a stressor, as it is considered elsewhere. In 2012, we conducted an assessment of emergent GSL wetlands to characterize the hydrology of the wetlands and determine the impact of hydrologic change on wetland condition. We gathered data on vegetation, soils, and sources of disturbance as well as detailed hydrologic information from 43 randomly selected emergent wetlands and calculated vegetation-based metrics to determine the condition of the wetlands and an index to determine the degree of human disturbance at each site. Hydrologic assessment indicated that hydroperiods are variable in both impounded and un-impounded sites; water level in wetlands declined, rose, or fluctuated throughout the growing season and the range of hydrologic change varied significantly regardless of the presence of impoundment. Preliminary condition assessment results suggest that hydrologic variability (determined by the range of water depth, change in area inundated during the growing season and distance to a water control structure) had the most significant impact of wetland condition (measured by the degree of invasiveness, presence of disturbance-tolerant taxa, and ratio of annual to perennial species). Condition was highest in wetlands with moderately declining water regimes, which represents the likely natural hydroperiod. The results of hydroperiod characterization and wetland assessment indicate that the decisions wetland managers make, whether to impound a wetland and how water levels are manipulated, are as important in determining wetland condition as the other disturbances the wetland experiences. Further, the sustainability of wetland functions depends on these management decisions. Results also suggest that trade-offs between maintaining wildlife habitat and other ecosystem functions depend on how water level is managed, and that sites can be managed to maintain all functions. This research will be conducted for three more years to monitor multi-year dynamics in hydrology and vegetation response

Characterizing the hydroperiod of emergent wetlands around the Great Salt Lake, Utah

Around the Great Salt Lake (GSL), Utah, impoundment and water level manipulation is a common management practice, originally established to protect wetlands at the terminal ends of rivers from major fluctuations caused by upstream water use. Discharge of the rivers that flow into the GSL and the elevation of the lake are well monitored, but the hydroperiod of wetlands in the deltas between the rivers and lake are unknown, as water levels in impounded wetlands vary based on water availability and management goals. Piezometers were installed at 50 emergent wetlands around the eastern shore of GSL as part of an ongoing ecological wetland condition assessment. The data from these piezometers, which record water level on an hourly basis through the growing season, provide data that can be used to characterize the hydroperiod of these wetlands, and the differences between impounded wetlands and those left un-impounded. There is great variability in the growing season hydroperiod for the wetlands monitored, but median water depth, timing of drawdown and duration of drawdown are consistent within all wetlands. However, water level variability and the depth of water level drawdown effectively distinguish impounded and un-impounded wetlands. When linked to data on wetland condition, this information can help guide decisions about wetland water management to protect wetland condition

Hydrologic Restoration and Management of Emergent Wetlands in the Arid West: Insights from a Condition Assessment of Great Salt Lake Wetlands

Wetland restoration and management is difficult in the Intermountain West, in part, because water is scarce and the links between hydrologic thresholds, drought, and wetland vegetation in this region are unknown. Climate change complicates matters by making water supplies more unreliable and wetlands prone to more frequent and extreme drought and flooding. Impoundment and water level management are strategies commonly adopted by managers around the Great Salt Lake (GSL), Utah, to buffer wetlands against fluctuations in unreliable and scarce water supplies and create the hydrologic conditions necessary to maintain obligate wetland plant species like bulrushes (Schoenoplectus spp.). As part of a wetland condition assessment and hydrologic monitoring project, we looked at the land-use and hydrologic factors associated with the establishment, growth, and reproduction of three species of interest for management and restoration in GSL wetlands: Schoenoplectus acutus, S. americanus, and S. maritimus. Results indicate that there are different land-use factors and hydrologic variables that favor the establishment of each species and that the conditions favoring large growth can be different from those associated with high seed production. S. acutus occurs most frequently in wetlands with minimal nearby land-use disturbances and more permanent hydroperiods. S. acutus biomass and seed production are highest in impounded sites that are saturated or shallowly flooded for more than 80% of the growing season. S. americanus is found most frequently in wetlands near developed land-use types that experience regular cattle grazing. S. americanus biomass production was highest in un-impounded sites with saturated soils, while seed production was higher in impounded sites that were flooded more deeply during the growing season. S. maritimus occurs in the widest variety of wetlands, but is most successful in sites where water levels are drawn down frequently and the range of depth experienced over the course of the growing season is \u3e70 cm. Biomass and seed production in S. maritimus was highest in sites where soils were saturated for longer periods during the growing season; seed production was highest in sites with frequent, large daily water level fluctuations. Our results indicate that managers can increase the likelihood of a successful restoration by picking the species best adapted to the degree of water level control present any wetland site

Keeping Wetlands Wet: Adapting to Uncertain Water Conditions at Bear River Migratory Bird Refuge

Bear River Migratory Bird Refuge is located at the end of the Bear River as it enters the Great Salt Lake. The Bear River is highly variable and heavily appropriated. This research explores how the Refuge has adapted to the physical and institutional realities of wetland management under uncertain river conditions. We conducted semi-structured interviews with wetland and water rights experts in the Bear River Basin, complimented by archival research of water rights and river conditions. This research shows that over the last 10 years, BRMBR received about 15% of the water needed to maintain their wetland habitat July through September, while receiving more than it needs most other months; the magnitude of this difference varies by year. Because of this untimely and uncertain water supply, BRMBR uses an adaptive management approach to predict their annual water supply, prioritize wetland units to keep flooded, and monitor the effects of management decisions. This management approach does not seek to recreate the natural hydrology of the river, but does maintain the most migratory bird habitat possible, creates a means for sharing information about the river, and proves the beneficial use of BRMBR water rights; these are important steps in meeting Refuge goals and maintaining good relationships with other water users

Wetlands without Water? A systematic review of drought effects on wetland plant communities

Wetlands in arid regions, like the western United States, regularly experience water shortages which likely will be exacerbated by climate change and increased human impacts on water supplies. Unfortunately, little consensus exists on the effects of drought on wetlands. Nor is it clear how wetland research can best inform management of wetlands in the face of declining water supplies. To address these limitations, we conducted a systematic literature review of the impacts of drought on wetland vegetation. We approached this analysis with four broad questions. First, where and why are studies about wetlands and drought being conducted? Second, how is drought defined and evaluated in the literature? Third, what are the known effects of drought on wetland plant communities, and have threshold effects been identified? Finally, how can we best manage wetlands in the face of drought and climate change? The results of the systematic review of 157 peer-reviewed studies show that most research is conducted in temperate-humid biomes, particularly in North America, primarily by academic researchers. The vast majority of studies are conducted in palustrine (non-tidal, emergent marshes) and freshwater systems. Most research analyzed one short-term drought event and the definitions of drought and measurements of its impact varied greatly. Drought was not defined at all in 30% of the studies; terms like drawdown and drought are often used interchangeably. Thresholds for drought impacts are rarely mentioned, but when they are, the focus is on thresholds with regard to the depth of a drought, the speed of a drought, or the life stage of vegetation experiencing drought. Very few studies sought to improve wetland management strategies; instead most wetland research tested general ecological theories. These findings suggest the need for more consistent research methods and definitions that cross ecology, hydrology, engineering, science policy, and other disciplines to make comparing or aggregating results of wetland studies possible and useful. There is also a need for more collaboration between researchers and managers who may have long-term data sets and insights into wetland response to various on-going management manipulations. In this way, research efforts can be made more relevant to management needs and to the types of drought that naturally occur, which are generally longer-term or more severe than what are evaluated in the literature. Finally, more research is needed to identify the impacts of drought on many different wetland types, particularly in regions that are not as well studied but are likely to experience water scarcity