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J.D. Riedle

Publications and source records attributed to J.D. Riedle.

3 recordsLinked to original sources

The dazed and confused identity of Agassiz's land tortoise, Gopherus agassizii (Testudines, Testudinidae) with the description of a new species, and its consequences for conservation

We investigate a cornucopia of problems associated with the identity of the desert tortoise, Gopherus agassizii Cooper. The date of publication is found to be 1861, rather than 1863. Only one of the three original cotypes exists, and it is designated as the lectotype of the species. Another cotype is found to have been destroyed in the 1906 San Francisco earthquake and subsequent fire. The third is lost. The lectotype is genetically confirmed to be from California, and not Arizona, USA as sometimes reported. Maternally, the holotype of G. lepidocephalus Ottley et Velázques Solis, 1989 from the Cape Region of Baja California Sur, Mexico is also from the Mojavian population of the desert tortoise, and not from Tiburon Island, Sonora, Mexico as previously proposed. A suite of characters serve to diagnose tortoises west and north of the Colorado River, the Mojavian population, from those east and south of the river in Arizona, USA and Sonora and Sinaloa, Mexico, the Sonoran population. Species recognition is warranted and because G. lepidocephalus is from the Mojavian population no names are available for the Sonoran species. Thus, a new species, Gopherus morafkai sp. n., is named and this action reduces the distribution of G. agassizii to only 30% of its former range. This reduction has important implications for the conservation and protection of G. agassizii , which may deserve a higher level of protection.

Arizona, Baja California Sur, California, Sinaloa,↗

Population structure of the alligator snapping turtle, macrochelys temminckii, on the western edge of its distribution

A mark-recapture project on Macrochelys temminckii was conducted between 1997 and 2000 at Sequoyah National Wildlife Refuge, Muskogee and Sequoyah counties, in eastern Oklahoma. Turtles were captured in all streams and exhibited equal sex ratios, marked sexual-size dimorphism, and population densities between 28 and 34 animals per km stretch of stream. There was evidence of past population perturbations, with very few large adults captured, and a cohort of subadults highly underrepresented. ?? 2008 Chelonian Research Foundation.

Chelonian Conservation and Biology↗

Microhabitat use, home range, and movements of the alligator snapping turtle, Macrochelys temminckii, in Oklahoma

Little is known about the ecology of the alligator snapping turtle, Macrochelys temminckii, particularly dentography and behavior. To learn more about the species in Oklahoma, we conducted a telemetry project on 2 small streams at Sequoyah National Wildlife Refuge, an 8,417.5-ha refuge located in east-central Oklahoma. Between June 1999 and August 2000, we fitted 19 M. temminckii with ultrasonic telemetry tags and studied turtle movements and microhahitat use. Turtles were checked 2 to 3 times weekly in summer and sporadically in winter. Several microhabitat variables were measured at each turtle location and a random location to help quantify microhabitat use vs. availability. We recorded 147 turtle locations. Turtles were always associated with submerged cover with a high percentage of overhead canopy cover. Turtles used deeper depths in late summer (but not deeper depths than random locations) and deeper depths in mid-winter (and deeper depths than random locations) than in early summer. They used shallower depths than random locations in early summer. This seasonal shift in depth use might be thermoregulatory, although evidence for this is indirect. The mean linear home range for all turtles was 777.8 m. Females had larger home ranges than males, and juveniles had larger home ranges than adults, although the latter was not statistically significant. Macrochelys temminckii used submerged structures as a core site, and stayed at each core site for an average of 12.3 d.

Southwestern Naturalist↗