Date of Graduation

Summer 2018


Master of Science in Biology



Committee Chair

Day Ligon


Macrochelys temminckii, head-starting, captive husbandry, microbiome, growth

Subject Categories

Integrative Biology


Due to historic overharvest and habitat degradation, the alligator snapping turtle (Macrochelys temminckii) has experienced population declines throughout its range. Tishomingo National Fish Hatchery in southern Oklahoma began a captive head-start program for this species in 2000 and has since released over 1,400 turtles in the region. However, there has been a recurring trend of turtles growing faster after release than while in captivity. My research sought to investigate this pattern by determining: 1) the influence of housing enrichment and housing density on juvenile growth rates and stress in indoor enclosures, and 2) the effects of supplementing hatchlings with adult feces to enhance the gut microbiome. I found that the presence of floating mats in indoor tanks improved growth rates compared to other structural components. Group density did not affect average growth rates, but animals that were housed communally exhibited more variable growth than individuals housed without conspecifics present. When exposed to feces of adult conspecifics, hatchlings assimilated fiber components of their omnivorous diet more efficiently than those exposed only to deionized water or creek water. Based upon these results, flotant structures and exposure to microbes found in the feces of adult M. temminckii are recommended for future head-start efforts.


© Kristen Erin Sardina

Available for download on Friday, December 31, 2021

Open Access