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Assessing the Ecological Condition of Nebraska's Wetland Resources and Amphibian Communities: An Intensification of the Environmental Protection Agency's 2011 National Wetland Condition Assessment

Nicholas A Smeenk, University of Nebraska - Lincoln

Abstract

Wetlands provide valuable ecosystem services including flood control, nutrient retention, recreational opportunities, and wildlife habitat. Despite their importance, wetlands were historically displaced across the landscape in favor of alternative landuses. While general trends in wetland area have been tracked, the ecological condition of wetlands remains largely unknown. From 2011 – 2013, I conducted ecological assessments at 109 wetland sites in 11 wetland complexes across Nebraska. Using a novel standardized Floristic Quality Assessment Index score and additional vegetative metrics, I tested the efficacy of multiple landscape methods and the Nebraska Wetland Rapid Assessment Method for assessing the ecological condition of wetland sites in Nebraska.The Rainwater Basins of central Nebraska represent a biologically and economically important region. Most of Nebraska’s native anuran species have ranges that include the Rainwater Basins. From 2014 – 2016, volunteer roadside anuran call surveys were conducted at 124 wetland sites in the Eastern Rainwater Basins. I used occupancy modeling in conjunction with muli-model inference and model averaging to assess detection and occupancy of four species and a small, four species anuran community. Generally, detection was not affected by weather covariates, but varied with date and time of day and occupancy was most influenced by wetland type, with managed wetland more likely to be occupied than anthropogenic habitats.The amphibian disease Chytridiomycosis is a potential cause of worldwide amphibian declines. I assessed the distribution of chytrid in Nebraska amphibian communities using the program MaxEnt. Results indicate that chytrid is widespread with the distribution best predicted by mean annual temperature and the type of aquatic habitat. Probability of chytrid presence peaked around 10.5 °C and was higher in lentic aquatic habitats.Results of this research provide baseline data for Nebraska’s wetlands and wetland reliant amphibian communities. Further, these results illustrate the need to consider multiple spatial scales and the importance of spatial context for ecosystem conservation planning and management. While plant communities thrive with minimal 100 m vegetative buffers, other taxa such as anurans and birds may respond to factors at much larger spatial scales and require broader planning and consideration of context, particularly in highly modified agricultural landscapes.

Subject Area

Natural Resource Management|Wildlife Conservation|Ecology

Recommended Citation

Smeenk, Nicholas A, "Assessing the Ecological Condition of Nebraska's Wetland Resources and Amphibian Communities: An Intensification of the Environmental Protection Agency's 2011 National Wetland Condition Assessment" (2019). ETD collection for University of Nebraska-Lincoln. AAI22587199.
https://digitalcommons.unl.edu/dissertations/AAI22587199

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