Analysis of the movement & home range of the Sonoyta mud turtle (Kinosternon sonoriense longifemorale) in the Sonoyta River, Sonora, Mexico

Authors: Miguel Garcia, Michael Bogan

Year: 2022

Abstract

For this study, the movements, home range, and activity of the Sonoyta short-breasted turtle (Kinosternon sonoriense longifemorale) were quantified in two sites within the Sonoyta River, Sonora, Mexico. The technique used to collect data was radiotelemetry. The first site within the area of study is called Agua Dulce reach, where 23 turtles were tracked over a four-year period. The second site is known as the Morelia site where 9 turtles were tracked over one year. The turtles in the Morelia section were specimens rescued from a dry sewage lagoon located 3km from the site in the town of Sonoyta, which were subsequently moved and released into the Sonoyta River. The movement and activity patterns of the turtles depended on the availability of water and varied according to their sex and size. Although the Sonoyta mud turtle is considered almost entirely as an aquatic reptile. It has been recorded aestivating on land during periods of extreme drought. Adult male tortoises at the Agua Dulce site made longer movements (Average Daily Distance (Add) = 4.62 m + 3.71) and had a larger home range area (3.7 ha) than adult females (Add = 2.3 m + 2.25; surface = 3.25 ha). Meanwhile, adult male turtles in Morelia also had longer movements (Add = 8.06 m + 3.68) and had a larger home range area (3.92 ha) than adult females (Add = 3.19 + 2.34; = 2.69 ha). No turtles were found outside the boundaries of the study site. Degradation and loss of water in the Sonoyta River can lead to the decline or disappearance of the available habitat of the Sonoyta mud turtle and its population.