scholarly journals Revisiting the hypothesis of sex-biased turtle road mortality

2019 ◽  
Vol 132 (3) ◽  
pp. 289-295 ◽  
Author(s):  
Sue Carstairs ◽  
Marc Dupuis-Desormeaux ◽  
Christina M. Davy
Keyword(s):  
Trauma Centre ◽  
Road Mortality ◽  
Substantial Impact ◽  
Emydoidea Blandingii ◽  
Painted Turtles ◽  
Snapping Turtles ◽  
Turtle Conservation ◽  
Map Turtles ◽  
Graptemys Geographica ◽  
Using Data

Road mortality poses a major threat to turtle populations. Several studies have suggested that the terrestrial movements associated with nesting increase this risk for females. The Ontario Turtle Conservation Centre (OTCC) is home to the Kawartha Turtle Trauma Centre, which admits 900 or more turtles a year, with road injuries the primary cause of admission. We tested the hypothesis that road mortality in turtles is female-biased using data from injured Midland Painted Turtles (Chrysemys picta marginata), Snapping Turtles (Chelydra serpentina), Blanding’s Turtles (Emydoidea blandingii), and Northern Map Turtles (Graptemys geographica) collected over about 126 000 km2 and admitted to OTCC’s hospital from January 2013 to October 2017. There was no difference in the number of male and female admissions of Midland Painted, Blanding’s, or Snapping Turtles (P > 0.05); however, more female Northern Map Turtles than males were admitted (P < 0.001). Admission of female turtles peaked in June during the nesting season, but male admissions were more evenly distributed throughout the season. Our admissions data provide a temporally unbiased and geographically broad snapshot of turtle–vehicle interactions that can directly inform conservation and management policies. Although our data are not equivalent to mortality rates, these results demonstrate that vehicle strikes can have a substantial impact on both female and male turtles.

scholarly journals Over-wintering Characteristics of West-Central Wisconsin Blanding's Turtles, Emydoidea blandingii

2010 ◽  
Vol 124 (2) ◽  
pp. 134 ◽  
Author(s):  
Richard P. Thiel ◽  
Timothy T. Wilder
Keyword(s):  
Chrysemys Picta ◽  
Anoxia Tolerance ◽  
Chelydra Serpentina ◽  
Emydoidea Blandingii ◽  
Anoxic Conditions ◽  
Painted Turtles ◽  
West Central ◽  
Remarkable Degree ◽  
Snapping Turtles

Hibernation of adult-sized Blanding's Turtles was studied at two west-central Wisconsin sites between 1991 and 2008. Turtles arrived at hibernacula from mid September to early October, spending 126 to 216 days at these sites, and generally emerged in early April yearly. Sixty percent of females and 30 percent of males hibernated in natural over man-made structures as hibernation sites. Anoxic conditions near five hibernation sites ranged from 78 to 100 days. Shell temperatures of three turtles monitored over five winters remained at <1°C a mean of 2,274 hours each winter. Over the same period, four turtles' temperatures were between 0° and -1°C a mean of 302 hours. During the course of our study, hibernating west-central Wisconsin Blanding's Turtles demonstrated a remarkable degree of both cold and anoxia-tolerance similar to that observed among Painted Turtles (Chrysemys picta) and Snapping Turtles (Chelydra serpentina).

Seasonality and interspecific and intraspecific asynchrony in emergence from the nest by hatchling freshwater turtles

2013 ◽  
Vol 91 (7) ◽  
pp. 451-461 ◽  
Author(s):  
P.J. Baker ◽  
J.P. Costanzo ◽  
J.B. Iverson ◽  
R.E. Lee
Keyword(s):  
Late Summer ◽  
Specific Pattern ◽  
Freshwater Turtles ◽  
Natal Nest ◽  
Painted Turtles ◽  
Emergence Patterns ◽  
History Of ◽  
Map Turtles ◽  
Graptemys Geographica ◽  
Species Specific

Timing of emergence from the natal nest is a variable trait in the life history of turtles. In theory, hatchling turtles that emerge synchronously, within and among nests, should gain a survival advantage over hatchlings that emerge independently. We examined emergence patterns for seven species of freshwater turtles that use a common nesting area in northern Indiana, USA. Hatchlings of four species emerged from the nest exclusively in late summer or early fall. However, hatchlings of three species usually overwintered in the nest chamber and emerged the following spring. Interspecific and intraspecific emergence from the nest was more synchronous in fall than in spring. Mean date of fall emergence from the nest did not vary among species; however, a species-specific pattern of emergence was observed in spring. Midland Painted Turtles (Chrysemys picta marginata Agassiz, 1857) emerged in late March and early April and, on average, these hatchlings left their nests 2 weeks earlier than Northern Map Turtles (Graptemys geographica (Le Sueur, 1817)) and 4 weeks earlier than Red-eared Sliders (Trachemys scripta elegans (Wied-Neuwied, 1839)). Although hatchlings of C. p. marginata are smaller than those of G. geographica and T. s. elegans, presumably they gain a survival or growth advantage by emerging earlier.

scholarly journals Emydid herpesvirus 1 infection in northern map turtles (Graptemys geographica) and painted turtles (Chrysemys picta)

2015 ◽  
Vol 27 (3) ◽  
pp. 392-395 ◽  
Author(s):  
Robert J. Ossiboff ◽  
Alisa L. Newton ◽  
Tracie A. Seimon ◽  
Robert P. Moore ◽  
Denise McAloose
Keyword(s):  
Chrysemys Picta ◽  
Painted Turtles ◽  
Herpesvirus 1 ◽  
Map Turtles ◽  
Graptemys Geographica

scholarly journals Road Mortality of Reptiles and Other Wildlife at the Ojibway Prairie Complex and Greater Park Ecosystem in Southern Ontario

2016 ◽  
Vol 130 (1) ◽  
pp. 64 ◽  
Author(s):  
Jonathan D. Choquette ◽  
Lindsey Valliant
Keyword(s):  
At Risk ◽  
Tallgrass Prairie ◽  
Species At Risk ◽  
Road Mortality ◽  
Emydoidea Blandingii ◽  
Reptile Species ◽  
Sternotherus Odoratus ◽  
Sistrurus Catenatus Catenatus ◽  
Graptemys Geographica ◽  
Mortality Survey

The Ojibway Prairie Complex in Windsor contains the largest protected tallgrass prairie ecosystem in Ontario and supports numerous species at risk. Despite its ecological significance, it is crossed by multiple high-traffic roads. Road mortality is a major threat to endangered species in Canada, particularly reptiles. The main goal of this study was to describe the nature and extent of vertebrate road mortality, with a focus on reptiles, on roads bisecting the Ojibway Prairie Complex, and the Greater Park Ecosystem, in Windsor and Lasalle, Ontario. A systematic road mortality survey was conducted by bicycle along seven roads (12.5 km) in 2010, 2012, and 2013. Also, opportunistic observations (n = 103) spanning over 30 years were assembled from a variety of sources. In total, 2083 vertebrates (49 species), including 446 reptiles (11 species), were recorded “dead onroad” during systematic surveys. The highest diversity of reptiles was recorded on Matchette Road, whereas the highest rate of reptile mortality was recorded on Malden Road. Reptile species at risk were killed on all roads surveyed. Combining systematic and opportunistic data, we found seven reptile species at risk: Butler’s Gartersnake (Thamnophis butleri), Eastern Foxsnake (Pantherophis vulpinus), Eastern Massasauga (Sistrurus catenatus catenatus), Blanding’s Turtle (Emydoidea blandingii),Eastern Musk Turtle (Sternotherus odoratus), Northern Map Turtle (Graptemys geographica), and Snapping Turtle (Chelydra serpentina). Reptile road mortality “hotspots” occurred where each road is intersected by a naturalized utility right-of-way. Our results can be used to focus mitigation efforts in space and time to reduce mortality rates and enhance connectivity in the Ojibway Prairie Complex and Greater Park Ecosystem.

25. Snapping Turtle Conservation in Ontario

2018 ◽  
Author(s):  
Rachel Wilson ◽  
Payal Samuel ◽  
Molly Teather ◽  
Leslie Usher ◽  
Jake Windsor
Keyword(s):  
Developmental Process ◽  
Public Awareness ◽  
Conservation Strategy ◽  
Food Sources ◽  
Road Mortality ◽  
Conservation Area ◽  
Snapping Turtle ◽  
Snapping Turtles ◽  
Turtle Conservation ◽  
Special Concern

Populations of snapping turtles are declining in Ontario. These reptiles play essential roles in wetland habitats through removal of dead animals and weeds, and their eggs provide food sources for mammals and birds. Despite being listed as a species of special concern under Ontario’s Endangered Species Act, hunting of snapping turtles is permitted in some regions of Ontario. Snapping turtles are further threatened by pollution, road mortality, and habitat loss. The developmental process of this species also acts as an obstacle to their recovery, as sexual maturity is not reached until the age of 16-19 and only 7 out of 10,000 eggs is expected to survive to adulthood.  With the assistance of contacts at the Suzuki Foundation, Guelph University, and other institutions, we intend to develop a conservation strategy for snapping turtles that consists of four components. First, we recommend a government-mandated, province-wide survey of snapping turtle statistics to determine turtle populations and threats. Then we will address whether sustainable hunting is possible. The current catch allowance of two turtles per person daily, as deemed sustainable by the MNR, should be suspended until further review. Next, barriers to recovery will be addressed. Prevention of threats could be achieved through conservation area designations, signs indicating turtle presence, information on how to avoid causing turtle injury and distribution of information to persons whose property contains snapping turtle habitat. Finally, increasing public awareness of snapping turtle demographics is crucial to our strategy. Education through multiple channels will generate public interest and funding.

More sires may enhance offspring fitness in Northern Map Turtles (Graptemys geographica)

2013 ◽  
Vol 91 (8) ◽  
pp. 581-588 ◽  
Author(s):  
Nicola Banger ◽  
Gabriel Blouin-Demers ◽  
Grégory Bulté ◽  
Stephen C. Lougheed
Keyword(s):  
Sexual Selection ◽  
Reproductive Success ◽  
Hatching Success ◽  
Locomotor Performance ◽  
Conservative Estimate ◽  
Genetic Quality ◽  
Offspring Fitness ◽  
Sexual Selection Theory ◽  
Map Turtles ◽  
Graptemys Geographica

Sexual selection theory predicts that males should be promiscuous to maximize their reproductive success, while females should be choosy. Yet females of many taxa often produce progeny sired by multiple males, indicating that promiscuity can be important for the reproductive success of females. Promiscuity may enhance the fitness of females if it increases the genetic quality, or the genetic variety, and thus the viability of their offspring. We quantified the number of sires per clutch in a population of Northern Map Turtles (Graptemys geographica (LeSueur, 1817)) in Lake Opinicon, Ontario, Canada, and tested whether the number of sires affects several metrics of viability in hatchlings. Based on the most conservative estimate, at least 71% of clutches in this population are sired by multiple males, but there was no evidence that larger clutches are sired by more males. Clutches sired by more males had higher hatching success and survival, but the differences were not statistically significant. We did not find any effect of the number of sires on hatchling morphology or locomotor performance. Collectively, our results partially support the hypothesis that promiscuity can increase the reproductive success of female Northern Map Turtles.

scholarly journals Mass mortality of Northern Map Turtles (Graptemys geographica)

2015 ◽  
Vol 129 (1) ◽  
pp. 80 ◽  
Author(s):  
Jordan Catrysse ◽  
Emily Slavik ◽  
Jonathan Choquette ◽  
Ashley E. Leifso ◽  
Christina M. Davy
Keyword(s):  
Lake Erie ◽  
Mass Mortality ◽  
Species At Risk ◽  
Long Term Effects ◽  
North Shore ◽  
The North ◽  
The Poor ◽  
Map Turtles ◽  
Graptemys Geographica

We report a mass mortality of Northern Map Turtles (Graptemys geographica [LeSueur, 1817]) on the north shore of Lake Erie, Ontario, Canada. Thirty-five dead adult females were recovered from a nesting area over a period of four weeks. Predation and boat strikes were both excluded as potential cause of death, but the actual cause could not be determined because of the poor condition of the carcasses. Other possible explanations for the mortality include poisoning, drowning, and infection with an unidentified pathogen. Mass mortality in long-lived species, such as turtles, can have long-term effects on population growth and is a cause for concern in a species at risk.

Fluid Tonicity Affects Peritoneal Characteristics Derived by 3-PORE Model

2019 ◽  
Vol 39 (3) ◽  
pp. 243-251 ◽  
Author(s):  
Joanna Stachowska-Pietka ◽  
Jan Poleszczuk ◽  
Josep Teixido-Planas ◽  
Josep Bonet-Sol ◽  
Maria I. Troya-Saborido ◽  
...  
Keyword(s):  
Model Fitting ◽  
Hydraulic Conductance ◽  
Membrane Properties ◽  
Patient Specific ◽  
Model Parameters ◽  
Peritoneal Membrane ◽  
Substantial Impact ◽  
Pore Model ◽  
Using Data ◽  
The Impact

Background It is typically assumed that within short time-frames, patient-specific peritoneal membrane characteristics are constant and do not depend on the initial fluid tonicity and dwell duration. The aim of this study was to check whether this assumption holds when membrane properties are estimated using the 3-pore model (3PM). Methods Thirty-two stable peritoneal dialysis (PD) patients underwent 3 8-hour peritoneal equilibration tests (PETs) with different glucose-based solutions (1.36%, 2.27%, and 3.86%). Temporary drainage was performed at 1 and 4 hours. Glucose, urea, creatinine, sodium, and phosphate concentrations were measured in dialysate and blood samples. Three-pore model parameters were estimated for each patient and each 8-hour PET separately. In addition, model parameters were estimated using data truncated to the initial 4 hours of peritoneal dwell. Results In all cases, model-estimated parameter values were within previously reported ranges. The peritoneal absorption (PA) and diffusive permeability for all solutes except sodium increased with fluid tonicity, with about 18% increase when switching from glucose 2.27% to 3.86%. Glucose peritoneal reflection coefficient and osmotic conductance (OsmCond), and fraction of hydraulic conductance for ultrasmall pores decreased with fluid tonicity (over 40% when switching from glucose 1.36%). Model fitting to the truncated 4-hour data resulted in little change in the parameters, except for PA, peritoneal hydraulic conductance, and OsmCond, for which higher values for the 4-hour dwell were found. Conclusion Initial fluid tonicity has a substantial impact on the 3PM-estimated characteristics of the peritoneal membrane, whereas the impact of dwell duration was relatively small and possibly influenced by the change in the patient's activity.

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