OutdoorNebraska

33 GUIDE TO NEBRASKA'S WETLANDS concentrated livestock waste, is a threat to the historically excellent water quality in the Sandhills. Although nitrate levels in the groundwater under the Sandhills generally are low, they do exceed safe limits (10 mg/L) in some locations, especially in the eastern edge, likely due to fertilizer applications on cropped areas (clearinghouse.nebraska.gov). Poorly sited, large-scale energy development and associated infrastructure, such as roads, as well as similar large- scale developments, can negatively affect large tracts of continuous grasslands and their associated wetlands. A potentially disastrous future threat is the sale and removal of groundwater to areas away from the Sandhills. With its extensive groundwater resources (Bleed and Flowerday 1990), the Sandhills area is sometimes touted for major water sales. Such a loss of water would greatly affect the region's lakes, marshes, and meadows because they are connected to the groundwater (Winter et al. 2001). Benefi ts Sandhills wetlands are extremely valuable to the region's ranchers and the ranching economy. These wetlands, especially the wet meadows, provide abundant and nutritious forage that is used as winter cattle feed. Wetlands also offer grazing sites and a source of water to livestock. More than 300 species of birds have been recorded in the Sandhills region. Of these, over 125, including large numbers of waterfowl, shorebirds, and waterbirds, rely on wetland habitats (Bleed and Flowerday 1990). The North American Waterfowl Management Plan lists the Sandhills as an area of greatest continental signifi cance to North American ducks, geese, and swans (U.S. Fish and Wildlife Service, Canadian Wildlife Service, and Mexican Ministry of Environment, Natural Resources, and Fisheries 2012). The Sandhills are the most important waterfowl production area in Nebraska and are considered by Bellrose (1980) to be the best duck production area south of the Prairie Pothole Region. Aerial surveys, corrected for visibility, conducted by the Nebraska Game and Parks Commission estimated an average of 94,576 ducks in the Sandhills during the 2003-2005 nesting seasons (Vrtiska and Powell 2011). However, with better wetland conditions, higher estimates (uncorrected for visibility) were observed in 1999-2002 than during the 2003-2005 nesting seasons (Vrtiska and Oldenburger 2002, and Matthew Garrick, pers. comm.). Thus, in years with more abundant precipitation, the actual number of breeding ducks in the Sandhills may exceed the estimates of Vrtiska and Powell (2011). The most common species of breeding ducks included mallard, blue-winged teal, gadwall, northern shoveler, and northern pintails, with smaller numbers of American wigeon, American green-winged teal, wood duck, ruddy duck, redhead, and canvasback also present (Vrtiska and Powell 2011). Production from the Sandhills Canada goose fl ock provides a fall fl ight that exceeds 20,000 birds (M. Vrtiska, pers. comm.). Trumpeter swans likely nested in the Sandhills historically, but were extirpated by the late 1800s. A reintroduction effort occurred at Lacreek National Wildlife Refuge, located in South Dakota north of Merriman, in the early 1960s, and the fl ock slowly expanded. An aerial survey of a portion of the Sandhills in 2016 and 2017 counted approximately 100 nesting pairs of trumpeter swans (M. Vrtiska, unpublish. data). There were 1,235 trumpeter swans counted in the 2022 mid-winter survey, which are mostly Sandhills-raised birds (M. Garrick, unpublish. data). Several state and federally listed threatened and endangered species use the Sandhills and associated wetlands. The migration corridor of the state and federally endangered whooping crane encompasses most of the Sandhills. Wet meadows provide habitat for the western prairie fringed orchid, which is a state and federally listed threatened species. Blanding's turtles are in decline across most of their range and are listed as threatened or endangered in adjacent states, but the population in the Sandhills appears to be doing well (Panella and Rothe-Groleau 2021, Haag 2022). Most of the lakes in the Sandhills are too shallow or Fens are a type of wetland that forms where cold groundwater continues to reach the surface even in dry years. This produces a micro climate that allows for ancient plants, such as this marsh marigold from the last Ice Age, to grow. DAKOTA ALTMAN, PLATTE BASIN TIMELAPSE

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