Recommendations for a Restoration Monitoring Plan for a Population of Massasauga Rattlesnakes in the Matthaei Botanical Gardens

Abstract

Habitat restoration efforts are crucial for the conservation of the eastern Massasauga rattlesnake (Sistrurus catenatus catenatus). Populations of this endangered species have declined, in part due to habitat loss and degradation. The study assessed vegetation cover at different stages of habitat restoration and Massasauga presence at the University of Michigan Matthaei Botanical Gardens located in Ann Arbor, Michigan, where there is an active population. Three study sites were selected to assess vegetation cover at different stages of habitat restoration and Massasauga presence. Vegetation surveys utilized the line intercept method to record the cover of woody plants and thistle along transects. Snake meander surveys, following established protocols, were conducted to assess Massasauga presence and abundance between May and Octoberof 2022 and 2023. Study sites were selected based on previous Massasauga surveys and habitat quality assessments. Results revealed variations in native and invasive plant species distribution, especially in the ground layer, where invasive woody plant species dominated; native woody plant species dominated the canopy layer. On the snake surveys, a total of 20 snakes were identified; most were found in the one site under the process of restoration the longest, which has unique topographic and vegetation characteristics. Also, 42 potential hibernacula were recorded. Results highlight associations between habitat characteristics and Massasauga presence, indicating the importance of continued research and adaptive management. The prevalence of invasive species, particularly in the ground layer, underscores ongoing challenges of managing non-native plants. Promising results in habitat improvement suggest the need for targeted invasive species removal and expanded monitoring efforts to ensure long-term conservation success. Expansion of monitoring efforts for Massasauga rattlesnakes with multiple trained observers and diverse survey methods is essential for accurate population assessments and informing adaptive management strategies to support the long-term conservation of the Massasauga rattlesnake and its habitat