Abnormal Shell Shapes in Northern Map Turtles of the Juniata River, Pennsylvania, USA

Nagle, Roy D.; Rowe, Christopher L.; Grant, Christopher J.; Sebastian, Emma R.; Martin, Benjamin E.

doi:10.1670/17-030

Cited by 6 publications

(2 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Turtles also lie on or bury into underwater substrates, especially during their winter dormancy called 'brumation', where toxins such as polychlorinated biphenyls (PCBs) and heavy metals accumulate [60]. The incidence and severity of shell anomalies in adult Northern Map Turtles (Graptemys geographica) in Pennsylvania corresponded to a growth period during which they were likely to have been exposed to the waste products of coal mining and to high egg incubation temperatures in those waste products [61]. Eggs of female Red-eared Sliders (Trachemys scripta elegans) from coal ash-contaminated sites that were incubated in uncontaminated soil still exhibited lower embryo survivorship than did eggs from uncontaminated sites [62].…”

Section: Reviewmentioning

confidence: 99%

Turtles and Tortoises Are in Trouble

et al. 2020

View full text Add to dashboard Cite

Turtles and tortoises (chelonians) have been integral components of global ecosystems for about 220 million years and have played important roles in human culture for at least 400,000 years. The chelonian shell is a remarkable evolutionary adaptation, facilitating success in terrestrial, freshwater and marine ecosystems. Today, more than half of the 360 living species and 482 total taxa (species and subspecies combined) are threatened with extinction. This places chelonians among the groups with the highest extinction risk of any sizeable vertebrate group. Turtle populations are declining rapidly due to habitat loss, consumption by humans for food and traditional medicines and collection for the international pet trade. Many taxa could become extinct in this century. Here, we examine survival threats to turtles and tortoises and discuss the interventions that will be needed to prevent widespread extinction in this group in coming decades.

show abstract

Section: Reviewmentioning

confidence: 99%

Turtles and Tortoises Are in Trouble

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Exposure to contaminants as well as thermal alteration of nesting substrates may cause sublethal effects in developing G. geographica. In Pennsylvania, Nagle et al (2018) reported that 29% of females nesting at a former industrial site along the Juanita River had carapace abnormalities, with older females displaying the highest frequency of abnormalities. The causes of the abnormalities are unclear but may have been related to historical soil or water contamination, or to the excessive temperatures that nests located in black coal tailings experienced at that site.…”

Section: 8mentioning

confidence: 99%

Graptemys geographica (LeSueur 1817) – Northern Map Turtle, Common Map Turtle

Vogt¹,

Bulté²,

Iverson³

2018

Chelonian Research Monographs

View full text Add to dashboard Cite

The Northern Map Turtle, Graptemys geographica (Family Emydidae), is a mediumsized sexually dimorphic freshwater turtle species (female carapace length to 292 mm, males to 160 mm) and the sister taxon to all other map turtle species. It is often common in rivers and lakes within its North American range. The turtles make extensive movements within their habitats for nesting, basking, and feeding. Mating occurs in fall and spring; hibernation lasts from October to mid-April in northern regions, and most hatchlings overwinter in the nest. Northern Map Turtles are primarily carnivorous, feeding predominately on snails, bivalves (including invasive dreisennid mussels), and aquatic insect larvae. Two to three clutches of 6 to 20 eggs are laid each year between late May and mid-July. Because males mature after about 4 years and females require about 10 years, adult sex ratios are often skewed towards males. Sex ratios are also influenced by nest temperatures, with warmer nests producing females and cool nests producing males. Direct and indirect human activities, including fisheries by-catch mortality, appear to be responsible for some population declines of this species in some regions, but G. geographica is not at this time considered Threatened.distRiBution. -Canada, USA. Southwestern Quebec and southeastern Ontario to central Alabama, northern Louisiana, west to central Minnesota and eastern Kansas and Arkansas, with scattered isolated populations in the northeastern USA in Vermont, New York, New Jersey, and Pennsylvania.

show abstract

Variation in shell morphology of the European pond turtle,Emys orbicularis, in fragmented central European populations

Horváth

Danko²,

Havaš³

et al. 2020

Biological Journal of the Linnean Society

View full text Add to dashboard Cite

The European pond turtle (Emys orbicularis) is a widely distributed freshwater species inhabiting much of Europe, but it is often in population decrease or is locally extinct. In this study, we sampled five central European populations, of which four were autochthonous and one was introduced outside the native range. Moreover, two of the native populations were relatively isolated and at the periphery of the species, range. Using the frequency of shell anomalies, a geometric morphometric framework and an analysis of fluctuating asymmetry, we aimed to determine the degree of morphological differentiation among different populations. Significantly, a smaller number of individuals with a malformed shell or scutes occurred in the native core range population, which potentially has a high level of gene flow (Hungary). Although neither canonical variate analysis nor the morphological disparity analysis showed distinct differences between populations, we found significantly higher shell asymmetry in the two marginal populations (Austria and Slovakia) compared with the core range populations. Our results might thus support the central–marginal hypothesis and indicate potential genetically based conservation problems owing to demographic bottlenecks and/or isolation in marginal populations.

show abstract

Abnormal Shell Shapes in Northern Map Turtles of the Juniata River, Pennsylvania, USA

Cited by 6 publications

References 43 publications

Turtles and Tortoises Are in Trouble

Turtles and Tortoises Are in Trouble

Graptemys geographica (LeSueur 1817) – Northern Map Turtle, Common Map Turtle

Variation in shell morphology of the European pond turtle,Emys orbicularis, in fragmented central European populations

Contact Info

Product

Resources

About