DETECTION AND OCCURRENCE OF NERODIA HARTERI (SERPENTES: COLUBRIDAE) IN AN UPPER PORTION OF THE BRAZOS RIVER WATERSHED

<p>Semiaquatic snakes are disproportionately impacted by habitat alteration adjacent to wetlands because of their reliance on both terrestrial and aquatic habitats. Brazos River Watersnakes, <em>Nerodia harteri</em>, are endemic natricines with one of the most restricted geographic ranges in North America. I quantified detection and site occupancy probabilities of <em>N. harteri</em> and its sympatric congeners (<em>N. erythrogaster</em> and <em>N. rhombifer</em>), as well as microhabitat selection within the <em>Nerodia</em> community. Within occupied transects, search effort was positively correlated with detecting <em>N. harteri</em>, whereas environmental and/or habitat variables were better predictors for detecting the sympatric congeners. Microhabitat selection between the three <em>Nerodia</em> species varied, with <em>N. harteri</em> selecting for riffle presence and increased canopy cover. The focal species was 97% less likely to be found in habitat characterized by bank vegetation containing saltcedar (<em>Tamarix</em> spp.). The results indicate the sympatric <em>Nerodia</em> spp. are partitioning their habitat to some degree, likely related to foraging activities. To better understand demographic trends of <em>Nerodia harteri</em>, long-term monitoring is needed, and habitat management — such as the preservation of riffle habitat — might be necessary to minimize the risk of continued population declines.</p>

Name thesis:degree_name

Master of Science - Biology

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Biology

Year dc:date.available

2022

Author dc:creator

• Yates, Jessica

Contributors dc:contributor

• Matthew Kwiatkowski
• Stephen J. Mullin
• Daniel Saenz

• Brazos River Watersnakes
• aquatic habitat
• niche overlap
• search effort
• Biology
• Ecology and Evolutionary Biology
• Terrestrial and Aquatic Ecology

Repository record dc:identifier

https://scholarworks.sfasu.edu/etds/447

OAI identifier oai:identifier

oai:scholarworks.sfasu.edu:etds-1464