Chelonian Conservation and Biology最新文献

{"title":"Assessing Head Morphology Dimorphism in the Midland Painted Turtle (Chrysemys picta marginata) Using a Photographic Questionnaire","authors":"Patrick D. Moldowan, R. Brooks, J. Litzgus","doi":"10.2744/CCB-1235.1","DOIUrl":"https://doi.org/10.2744/CCB-1235.1","url":null,"abstract":"Abstract The ability to identify the sex of animals accurately is important in population studies. Emydid turtles (Testudines: Emydidae) demonstrate a number of sexually dimorphic characters, including head (cranial) size and structure. Field observations from a long-term study of midland painted turtles (Chrysemys picta marginata) in Algonquin Provincial Park, Ontario, Canada, suggested distinct differences in external head morphology between the sexes. We evaluated these putative sexual differences in C. picta head morphology by conducting a visual questionnaire involving human observers of varying levels of experience (novice, beginner, intermediate, and advanced). Observers were capable of distinguishing the sexes based solely on head morphology with a high degree of accuracy (between 79% and 86% success) across experience levels. Observers identified head shape as a defining character distinguishing the sexes. We suggest that visual questionnaires are a quantifiable method of assessing dimorphic characters that can be used in addition to traditional morphometrics or geometric morphometrics to demonstrate a visual, rather than simply statistical, difference among characters and sexes. Despite the breadth of research conducted on C. picta, our study is among the first to describe, assess, and discuss the functional significance of head dimorphism in this model species.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"16 1","pages":"76 - 82"},"PeriodicalIF":0.7,"publicationDate":"2017-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2744/CCB-1235.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69181021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Factors Affecting the Long-Term Population Dynamics of Green Turtles (Chelonia mydas) in Ogasawara, Japan: Influence of Natural and Artificial Production of Hatchlings and Harvest Pressure","authors":"Satomi Kondo, Y. Morimoto, Takayuki Sato, H. Suganuma","doi":"10.2744/CCB-1222.1","DOIUrl":"https://doi.org/10.2744/CCB-1222.1","url":null,"abstract":"Abstract The Ogasawara Islands in Japan represent an important rookery for green sea turtles (Chelonia mydas) in the Pacific Ocean. The marine turtle population in these islands was severely depleted due to overexploitation in the 1800s; however, continuous nesting surveys starting in 1975 showed signs of a gradual recovery, and an upward trend of nesting females has been observed in recent years. The Japanese government undertook a “hatch and release project” to recover the turtle stock in 1910 as the world's first attempt of a sea turtle hatchery. A total of more than 251,000 hatchlings were released into the wild as a part of the project; however, its contribution to the recent increase in nesting females is not well understood. The increase in nesting females may be attributed to the temporary suspension of the turtle harvest and reduction of catch from 1942 to 1968, which allowed for stable production of hatchlings from natural beaches. This study documents the levels of harvest, number of nesting females, and hatchling production at Ogasawara and explores, for the first time, their influence on population dynamics of Ogasawara's green turtles.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"16 1","pages":"83 - 92"},"PeriodicalIF":0.7,"publicationDate":"2017-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2744/CCB-1222.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41962872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Orientation in Five Species of Hatchling River Turtles Dispersing from Experimental Nests","authors":"Michael J. Pappas, J. Congdon, Bruce J. Brecke","doi":"10.2744/CCB-1234.1","DOIUrl":"https://doi.org/10.2744/CCB-1234.1","url":null,"abstract":"Abstract Hatchling river turtles (Smooth Softshell Turtles, Apalone mutica; Spiny Softshell Turtles, Apalone spinifera; Northern Map Turtles, Graptemys geographica; False Map Turtles, Graptemys pseudogeographica; and Ouachita Map Turtles, Graptemys ouachitensis) were released in a variety of settings to help place orientation and dispersal from nests in the context of nest site selection by females and juvenile recruitment habitat. Visual cues associated with near open or far dark horizons were the primary environmental cues used during initial orientation and dispersal of the hatchling river turtles. On a river beach, hatchlings of both species of Softshell Turtles dispersed toward the open horizon of the nearby river. In contrast, hatchlings of all 3 species of Map Turtles on the same beach dispersed toward the near dark horizons of a forest that led them away from the river. Hatchling Map Turtles of all 3 species released in autumn and Northern Map Turtles also released in spring at a field arena dispersed toward near dark horizons of pine (Pinus spp.) and deciduous trees to the north and south of the arena (directions that were parallel to the Mississippi River). At a site in upland prairie habitat with no nearby wetlands, hatchlings of all 3 species of Map Turtles dispersed to the north toward near dark horizons of an oak (Quercus spp.) forest rather than toward more distant dark horizons of mixed oak and pine trees. At a lowland prairie site where no near dark horizon was visible, Northern Map Turtles dispersed toward 2 far dark horizons that were ∼ 230 m to the north (a pond surrounded with trees) and to the south (an area of large deciduous trees at the west end of a windrow of pine trees), but not toward the large riparian wetland 280 m to the west. The bimodal dispersal pattern toward 2 equidistant dark horizons within 230 m but not toward the riparian area 280 m to the west suggests that the perception distance for hatchling Northern Map Turtles is between 230 and 280 m. Dispersal of a combined sample of naïve hatchling False Map and Ouachita Map Turtles released in a mature corn field was not different from random, but the directions taken by the majority of hatchlings were to the north and south across corn rows that may be the closest match to dark horizons used for dispersal in typical habitats.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"16 1","pages":"11 - 3"},"PeriodicalIF":0.7,"publicationDate":"2017-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2744/CCB-1234.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43623620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prey Availability and Diet Analysis of Texas Diamond-Backed Terrapin (Malaclemys terrapin littoralis)","authors":"Bryan J. Alleman, G. Guillen","doi":"10.2744/CCB-1228.1","DOIUrl":"https://doi.org/10.2744/CCB-1228.1","url":null,"abstract":"Abstract The diamond-backed terrapin (Malaclemys terrapin) is the only North American turtle species specialized for living in brackish and saltmarsh environments. The Texas subspecies (Malaclemys terrapin littoralis) is found along most of the Texas Gulf Coast. Previous studies on the prey and diets of Atlantic and Florida subspecies found that the diet of terrapins primarily consisted of crustacean and molluscan species, although differences in dietary composition were observed between the sexes. Furthermore, prey availability had little effect on terrapin distribution within a marsh. We examined the prey availability and diet of Texas diamond-backed terrapins. Comparisons of random locations to terrapin capture locations indicated that prey availability is not a limiting factor affecting terrapin distribution in Texas marshes, but multiple significant seasonal and locational differences in prey were detected at capture sites. Fecal analysis, using multiple metrics, indicated Gastropoda and Decapoda as major components of the diets of Texas terrapins. Plicate horn snails (Cerithidea pliculosa) and fiddler crabs (Uca spp.) were important prey items for all terrapins. There were significant differences between the diets of male and female terrapins, among seasonal diets, and among diets of terrapins captured at different marsh sites. Our prey availability findings support previous studies, but results from fecal analysis indicate a slightly different diet for terrapins than previously reported in other studies. The combined results extend the basic knowledge and understanding of terrapin diets, which will be useful for ongoing conservation and management of M. terrapin, especially the Texas subspecies.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"16 1","pages":"52 - 61"},"PeriodicalIF":0.7,"publicationDate":"2017-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2744/CCB-1228.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43404965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Factors Affecting Nesting Times in the Painted Turtle Chrysemys picta in Nebraska","authors":"Aubrey Frye, Kate Hardy, Ashley R Hedrick, J. Iverson","doi":"10.2744/CCB-1208.1","DOIUrl":"https://doi.org/10.2744/CCB-1208.1","url":null,"abstract":"Abstract Although general descriptions of nesting in painted turtles (Chrysemys picta) are numerous, few studies have quantified the timing of the components of the nesting process, and no previous study has analyzed the factors influencing those times. The present study was conducted on the Crescent Lake National Wildlife Refuge in Garden County, Nebraska, in June 2012 and 2013 and focused on a single nesting population of female C. picta. We recorded times for the initiation of the nest foray, and the beginning and conclusion of nesting, and calculated search and construction times. Although highly variable, on average females left the marsh at 1709 hrs (n = 130), began nesting at 1745 hrs (n = 141), and finished nesting at 1915 hrs (n = 135). Search time averaged 26 min (n = 79) and nest construction time averaged 97 min (n = 104). We investigated the effects of female body size, air temperature, time of day, nest day, clutch number, substrate type, and reproductive output on these times. Smaller females nested earlier in the day, construction times were shorter in warmer temperatures, nests begun earlier in the day were completed more quickly, and nest times were longer earlier in the season and for first vs. second clutches. Soil type and measures of reproductive output had no effects on nesting times. These results suggest that temperature is a primary driver of nesting times, as these turtles exploit the afternoon–evening window of optimal temperatures, avoiding heat stress earlier in the afternoon and much colder evening temperatures as well as a presumed increase in predation risk after dark.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"16 1","pages":"44 - 51"},"PeriodicalIF":0.7,"publicationDate":"2017-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2744/CCB-1208.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46477775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chelonian Epitaph","authors":"","doi":"10.2744/1071-8443-16.1.110","DOIUrl":"https://doi.org/10.2744/1071-8443-16.1.110","url":null,"abstract":"Editorial Introduction. — This section is devoted to poetry involving turtles, representing either reprinted previously published or new unpublished material. We encourage our readers to submit poetry or songs for consideration, either their own material or work by other authors. Poems may be submitted to Anders G.J. Rhodin, Chelonian Research Foundation, E-mail: RhodinCRF@aol.com. Our desire is to share with our readers the beauty and wonder of turtles as expressed through the art of the poem or song. In the sense that the relationship between man and turtles is multifaceted, so too is turtle poetry. The poems we publish here will reflect that complexity, from poems of pure admiration for the creatures themselves to others reflecting the utilization of turtles and their products. Some poems will reflect man’s use of the turtle for sustenance, others will stress man’s need to preserve and protect turtles. Some will deal with our emotional interactions with turtles, others will treat turtles light-heartedly or with seeming disrespect, but all will hopefully help us to better understand both the human and the chelonian condition, and remind us that the turtle holds a sacred place in all our hearts.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"16 1","pages":"110 - 110"},"PeriodicalIF":0.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69178798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Turtle in the Road","authors":"","doi":"10.2744/1071-8443-16.2.255","DOIUrl":"https://doi.org/10.2744/1071-8443-16.2.255","url":null,"abstract":"Editorial Introduction. — This section is devoted to poetry involving turtles, representing either reprinted previously published or new unpublished material. We encourage our readers to submit poetry or songs for consideration, either their own material or work by other authors. Poems may be submitted to Anders G.J. Rhodin, Chelonian Research Foundation, E-mail: RhodinCRF@aol.com. Our desire is to share with our readers the beauty and wonder of turtles as expressed through the art of the poem or song. In the sense that the relationship between man and turtles is multifaceted, so too is turtle poetry. The poems we publish here will reflect that complexity, from poems of pure admiration for the creatures themselves to others reflecting the utilization of turtles and their products. Some poems will reflect man’s use of the turtle for sustenance, others will stress man’s need to preserve and protect turtles. Some will deal with our emotional interactions with turtles, others will treat turtles light-heartedly or with seeming disrespect, but all will hopefully help us to better understand both the human and the chelonian condition, and remind us that the turtle holds a sacred place in all our hearts.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"16 1","pages":"255 - 255"},"PeriodicalIF":0.7,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69178829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Factors Affecting Predation on Wood Turtle (Glyptemys insculpta) Nests in the Upper Peninsula of Michigan","authors":"Jenny L. Rutherford, G. Casper, B. Graves","doi":"10.2744/CCB-1180.1","DOIUrl":"https://doi.org/10.2744/CCB-1180.1","url":null,"abstract":"Abstract Depredation rates on turtle nests can be very high, resulting in low recruitment to populations. Understanding predator foraging habits and nesting ecology of turtles is essential for the long-term management of threatened turtle species. Cues used by predators to locate wood turtle (Glyptemys insculpta) nests were investigated by creating simulated nests with 1 of 4 treatments: soil disturbance, water with turtle scent, soil disturbance plus turtle scent, or distilled water. Nest predators primarily used soil disturbance cues for locating nests. Additionally, artificial nests with buried chicken eggs were created at varying distances from the river and monitored for predation. Nest predation decreased as nest distance from the river increased. These data can be used to develop strategies for more effective management of this threatened species.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"15 1","pages":"181 - 186"},"PeriodicalIF":0.7,"publicationDate":"2016-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2744/CCB-1180.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69179339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence and Transience of Ingested Fishing Hooks in Kemp's Ridley Sea Turtles","authors":"Andrew J. Heaton, Eric E. Pulis, J. Pitchford, Wendy Hatchett, A. Carron, Moby A Solangi","doi":"10.2744/CCB-1227.1","DOIUrl":"https://doi.org/10.2744/CCB-1227.1","url":null,"abstract":"Abstract In the northern Gulf of Mexico, Kemp's ridley sea turtles (Lepidochelys kempii) are incidentally captured by recreational anglers. While sea turtle bycatch is of conservation concern, most studies focus on commercial fisheries, and the number and proportion of turtles affected by recreational fisheries interactions is not known. This study aimed to quantify the proportion of turtles in the Mississippi Sound with evidence of previous interactions with anglers. We analyzed radiographs of hook-and-line captured sea turtles in rehabilitation for number of hooks present, location of hooks, and number of associated hook interactions. The presence of ingested hooks in a number of the rehabilitated L. kempii also allowed us to report on hook transience through observations in rehabilitation, including how transit time related to turtle size, hook size, and position within the gastrointestinal tract. From 2012 to 2015, 882 L. kempii were radiographed. Hooks from prior interactions were found in 12.5% of our total sample. Carapace length was not significantly related to the probability of gear presence, though carapace length did account for 21.9% of the variation of hook sizes in our sample. Transit times were recorded for 50 successfully expelled hooks. Average transit times were 13.50, 8.40, and 4.48 d for the upper, middle, and lower gastrointestinal tract, respectively. Multiple linear regression models showed that transit time was not related to hook or turtle size. This information can be used to inform sea turtle rehabilitation, conservation, and management decisions while highlighting the need for a better understanding of interactions between sea turtles and recreational fisheries.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"15 1","pages":"257 - 264"},"PeriodicalIF":0.7,"publicationDate":"2016-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2744/CCB-1227.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69180393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Olfaction as a Cue for Nest-Site Choice in Turtles","authors":"J. Iverson, Hanna Klondaris, Christopher S. Angell, Wendy P. Tori","doi":"10.2744/CCB-1199.1","DOIUrl":"https://doi.org/10.2744/CCB-1199.1","url":null,"abstract":"Abstract Nest-site choice in turtles has a demonstrated impact on their fitness. Previous studies of nest-site choice have focused on environmental factors potentially affecting that choice (e.g., temperature, insolation, soil type, or moisture). Observations of nesting of painted turtles (Chrysemys picta) at the Crescent Lake National Wildlife Refuge in the Nebraska Sandhills suggest that females might use olfactory cues (specifically odors of other nesting females) to choose nest sites. We tested this hypothesis indirectly by using the nearest neighbor (nest) distance algorithm in ArcMap 10.1. Our results for nests in 2012–2014 were mixed, with nesting at some sites, in some years, and by some turtles occurring nonrandomly, in very close proximity to previous nests. Preliminary experimental data from 2015 using urine-treated sites in primary nesting areas also suggested that females showed more interest in those sites than sites moistened with equal amounts of water. These data provide some support for the use of nest odor as an important cue for nest-site choice in turtles, but they are insufficient to reject the possibility of the simultaneous use of other fine-scale environmental cues.","PeriodicalId":50703,"journal":{"name":"Chelonian Conservation and Biology","volume":"15 1","pages":"206 - 213"},"PeriodicalIF":0.7,"publicationDate":"2016-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2744/CCB-1199.1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69180400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}