Springs Monitoring at Tuzigoot National Monument: 2024

The Sonoran Desert Inventory and Monitoring Network monitors one spring, Shea Spring, each year at Tuzigoot National Monument, Arizona. We assess the condition of the site, measure spring discharge and wetted extent (area that contained water), collect core water quality and water chemistry data, note the wetland plants and invasive plants and animals present, and sample for environmental DNA (eDNA) to inventory springs for rare species, invasive species, and pathogens. Each spring is somewhat unique, and Arizona has not adopted water quality standards that apply across the diversity of springs in the state. Therefore, we continue to collect water quality data at the spring to form a baseline reference of natural variance. We collected a total of 11 water samples for eDNA testing from Shea Spring (a rheocrene spring) and the adjacent Tavasci Marsh. We detected American bullfrog in nine samples and chytrid fungus in five samples. Both of these target organisms were present in Shea Spring and the marsh. Woodhouse’s toad was detected in one sample from the marsh. Shea Spring emerges from the bottom of a clear pool surrounded by cattails and feeds directly into the adjacent marsh. The spring had water when we visited in 2024, but persistence data are not available for the remainder of the year. In most years measured, the spring had water year round. Burned trees are present around the site from a fire in 2023, and there is evidence that beavers are using the site. In addition to the eDNA evidence of American bullfrog, we saw bullfrogs in the spring for the first time in 2024, though they have been commonly detected in Tavasci Marsh in prior years. We found red brome and Bermudagrass (invasive plants) at the spring, and wetland plants included cattail, horsetail, and at least two Carex species (sedge/rush). We do not collect wetted extent data at this spring to minimize disturbance to the site, and because it is on one corner of the larger marsh, making it difficult to define.