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Clay L Pierce

The data set associated with this metadata is included in three separate csv files: 'Occupancy_Data', 'Stage_Raw', and 'Flood_Stage_Height'. 'Occupancy_Data' was used to fit the dynamic occupancy models and includes 17 columns: Time: time periods numbered 1 to 5; 'Oxbow': individual oxbows numbered 1 through 10; 'OxbowName': the name of each oxbow; 'Species': species encountered during sampling, numbered 1 to 16; 'SpeciesName': common and scientific names for each species; 'Occ1', 'Occ2', 'Occ3': detection (1) and non-detection data for each Time, Oxbow, Species combination across 3 survey occasions (NAs represent surveys that did not occur); Binary-coded life history characteristics (traits) for each species:...
Amphibians living in agricultural areas encounter many challenges. Two factors affecting individuals in these landscapes are habitat loss and pesticides. This thesis focuses on amphibians using agricultural wetlands in Iowa, where row crops such as corn and soybeans dominate the landscape. The goal of my first study was to determine the influences of site characteristics on amphibian presence and success. I used occupancy analysis to estimate proportion of area occupied by four species as a function of eight covariates hypothesized to affect occupancy: fish abundance, salamander abundance, invertebrate density, vegetative cover, wetland area, water atrazine concentration, surrounding crop land use, and overall wetland...
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