Nichole D. Bishop, J. Polisar, P. Eliazar, R. Carthy, K. Bjorndal
Abstract. Dermatemys mawii is a critically endangered freshwater turtle endemic to Central America. In the wild, these turtles are thought to be wholly herbivorous as adults and feed on a variety of vegetation; however, no studies have quantitatively assessed potential dietary differences based on biotic and abiotic factors. The purpose of our study was to describe and quantify the wild diet of D. mawii and assess differences based on habitat, maturity, and sex. We evaluated the stomach contents of 66 turtles legally harvested by local hunters for personal consumption throughout the country of Belize. Percent volume (by displacement) and percent frequency of each stomach item were used to calculate an index of relative importance (IRI). One algal and 6 plant families contributed to an overall diet composition consisting of leaves, flowers, stems, seedpods, seeds, and fruit. Rocks and invertebrates were also consumed, although we believe these to be incidental consumption. The leaves of the riparian tree Inga edulis were present in 73.1% of turtle stomachs and accounted for almost half of the total volume of all stomach contents combined. We used Spearman rank correlation coefficients to test the null hypothesis that there was no correlation in the rankings of stomach items (i.e., there were differences) when comparing turtles by habitat, age, and sex. There were significant differences in the ranking of food items between river and lagoon habitats, with lagoon turtles relying heavily on the algae Nitella sp.; however, the stomach contents from both habitats were equally diverse (Hrivers = 1.68, Hlagoons = 1.64). There were no differences in IRIs between adults and juveniles or between males and females. Our results emphasize the importance of habitat in D. mawii diet selection and the importance of leaves from riparian plants species that are shed into their aquatic habitats.
{"title":"Diet of Dermatemys mawii, an Aquatic Turtle That Relies Heavily on Terrestrial Vegetation","authors":"Nichole D. Bishop, J. Polisar, P. Eliazar, R. Carthy, K. Bjorndal","doi":"10.2744/CCB-1467.1","DOIUrl":"https://doi.org/10.2744/CCB-1467.1","url":null,"abstract":"Abstract. Dermatemys mawii is a critically endangered freshwater turtle endemic to Central America. In the wild, these turtles are thought to be wholly herbivorous as adults and feed on a variety of vegetation; however, no studies have quantitatively assessed potential dietary differences based on biotic and abiotic factors. The purpose of our study was to describe and quantify the wild diet of D. mawii and assess differences based on habitat, maturity, and sex. We evaluated the stomach contents of 66 turtles legally harvested by local hunters for personal consumption throughout the country of Belize. Percent volume (by displacement) and percent frequency of each stomach item were used to calculate an index of relative importance (IRI). One algal and 6 plant families contributed to an overall diet composition consisting of leaves, flowers, stems, seedpods, seeds, and fruit. Rocks and invertebrates were also consumed, although we believe these to be incidental consumption. The leaves of the riparian tree Inga edulis were present in 73.1% of turtle stomachs and accounted for almost half of the total volume of all stomach contents combined. We used Spearman rank correlation coefficients to test the null hypothesis that there was no correlation in the rankings of stomach items (i.e., there were differences) when comparing turtles by habitat, age, and sex. There were significant differences in the ranking of food items between river and lagoon habitats, with lagoon turtles relying heavily on the algae Nitella sp.; however, the stomach contents from both habitats were equally diverse (Hrivers = 1.68, Hlagoons = 1.64). There were no differences in IRIs between adults and juveniles or between males and females. Our results emphasize the importance of habitat in D. mawii diet selection and the importance of leaves from riparian plants species that are shed into their aquatic habitats.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115624516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Evolutionary theories predict major differences in life-history trait values of long- and short-lived organisms. Such comparisons have not been possible for chelonians because no short-lived turtle was known until research revealed that chicken turtles (Deirochelys reticularia; DR) have a maximum longevity of 21 yrs. Life-history trait values of DR females are 1) age at maturity of females = 5–6 yrs; 2) clutches per season = 1.6; 3) annual fecundity = 6–8 female eggs per female; 4) average juvenile survivorship from age 1 to maturity = 0.60; and 5) low average annual adult survivorship = 0.66. We compared DR with the very long-lived Blanding's turtles (Emydoidea blandingii; EB) in Michigan. Over 14 yrs with no mortality (the minimum age at maturity of EB), the maximum potential fecundity produced by a single female embryo and her mature female offspring was 5 female eggs for EB and 1040 eggs for DR. Comparisons of life table output for approximately stable populations of DR and EB resulted in cohort generation times of 7 and 37 yrs, respectively. The life-history prediction that short-lived organisms should produce smaller offspring was not supported. Average wet mass of eggs is 10 g (8.4–11.3 g) for DR and 12 g (10–14 g) for EB; and average wet mass of hatchlings is 7.3 g (6–9 g) for DR and 9.3 g (6–13 g) for EB. Both differences are smaller than expected based on the difference in longevity. Short-lived female DR have an unusual tactic of investing in high fecundity and making substantial body size-specific investment in large eggs, which may reflect why juvenile survivorship had greater influence on population change rates than did adult survivorship. In contrast, adult survivorship had the greatest influence on population change rates of EB. Comparison of cohorts of 1000 female DR and EB hatchlings highlights the differences in life histories of short- and long-lived turtles: all DR would be dead by the time the last female EB had reached maturity at 21 yrs of age.
摘要进化理论预测了长生和短生生物在生活史特征值上的主要差异。对龟类动物进行这样的比较是不可能的，因为直到研究发现鸡龟(Deirochelys reticularia;DR)的最长寿命为21年。DR雌性的生活史特征值为:1)雌性成熟年龄= 5 ~ 6岁;2)每赛季的离合器= 1.6;3)年繁殖力=每只雌虫产6-8个卵;4) 1岁至成熟期平均幼鱼存活率= 0.60;5)成人年平均生存率低= 0.66。我们将DR与非常长寿的布兰丁龟(Emydoidea blandingii;EB)在密歇根州。在没有死亡的14岁以上(EB成熟时的最小年龄)，单个雌性胚胎及其成熟雌性后代产生的最大潜在繁殖力为EB的5个雌性卵子和DR的1040个卵子。比较大约稳定的DR和EB种群的生命表输出结果分别为7年和37年。生命周期短的生物会产生更小的后代的生命史预测没有得到支持。DR的平均湿质量为10克(8.4-11.3克)，EB为12克(10 - 14克);DR和EB的平均湿质量分别为7.3 g (6-9 g)和9.3 g (6-13 g)。这两种差异都小于基于寿命差异的预期。寿命短的雌性DR有一种不寻常的策略，即投资于高繁殖力，并在大的卵上进行大量的身体尺寸特定的投资，这可能反映了为什么幼鱼的存活率对种群变化率的影响比成年鱼的存活率更大。成人存活率对EB种群变化率的影响最大。1000只雌性长尾龟和雌性长尾龟的对比突出了短寿命和长寿命龟的生活史差异:当最后一只雌性长尾龟在21岁时成熟时，所有的长尾龟都会死亡。
{"title":"Comparing Life Histories of the Shortest-Lived Turtle Known (Chicken Turtles, Deirochelys reticularia) with Long-Lived Blanding's Turtles (Emydoidea blandingii)","authors":"J. Congdon, K. Buhlmann, J. Gibbons","doi":"10.2744/CCB-1521.1","DOIUrl":"https://doi.org/10.2744/CCB-1521.1","url":null,"abstract":"Abstract. Evolutionary theories predict major differences in life-history trait values of long- and short-lived organisms. Such comparisons have not been possible for chelonians because no short-lived turtle was known until research revealed that chicken turtles (Deirochelys reticularia; DR) have a maximum longevity of 21 yrs. Life-history trait values of DR females are 1) age at maturity of females = 5–6 yrs; 2) clutches per season = 1.6; 3) annual fecundity = 6–8 female eggs per female; 4) average juvenile survivorship from age 1 to maturity = 0.60; and 5) low average annual adult survivorship = 0.66. We compared DR with the very long-lived Blanding's turtles (Emydoidea blandingii; EB) in Michigan. Over 14 yrs with no mortality (the minimum age at maturity of EB), the maximum potential fecundity produced by a single female embryo and her mature female offspring was 5 female eggs for EB and 1040 eggs for DR. Comparisons of life table output for approximately stable populations of DR and EB resulted in cohort generation times of 7 and 37 yrs, respectively. The life-history prediction that short-lived organisms should produce smaller offspring was not supported. Average wet mass of eggs is 10 g (8.4–11.3 g) for DR and 12 g (10–14 g) for EB; and average wet mass of hatchlings is 7.3 g (6–9 g) for DR and 9.3 g (6–13 g) for EB. Both differences are smaller than expected based on the difference in longevity. Short-lived female DR have an unusual tactic of investing in high fecundity and making substantial body size-specific investment in large eggs, which may reflect why juvenile survivorship had greater influence on population change rates than did adult survivorship. In contrast, adult survivorship had the greatest influence on population change rates of EB. Comparison of cohorts of 1000 female DR and EB hatchlings highlights the differences in life histories of short- and long-lived turtles: all DR would be dead by the time the last female EB had reached maturity at 21 yrs of age.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130110930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-21DOI: 10.2744/1071-8443-21.1.1
Jeffrey A. Seminoff
Here you will find 15 articles with conservation and research efforts reported from seven countries (Australia, Brazil, Cuba, Lao People's Democratic Republic, Philippines, United States, and Venezuela) and data presented for 15 species: Caretta caretta (loggerhead), Chelonia mydas (green turtle), Chelydra serpentina (snapping turtle), Deirochelys reticularia (chicken turtle), Dermatemys mawaii (Central American river turtle), Emydoidea blandingii (Blanding's turtle), Eretmochelys imbricata (hawksbill), Gopherus polyphemus (gopher tortoise), Lepidochelys kempii (Kemp's ridley), Lepidochelys olivacea (olive ridley), Macrochelys suwanniensis (Suwannee alligator snapping turtle), Macrochelys temminckii (alligator snapping turtle), Malayemys khoratensis (Khorat snail-eating turtle), Myuchelys bellii (Bell's turtle), and Siebenrockiella leytensis (Palawan forest turtle). In addition to this diversity of turtle and tortoise species, the research and conservation topics covered in this issue are wide ranging, and include anatomy and physiology, comparative life history analysis, demography and distribution, sea turtle stranding and bycatch research, genetic research, diet analysis, predation abatement strategies, veterinary science, and elaboration of local ecological knowledge.
{"title":"Chelonian Conservation and Biology, Volume 21, Issue 1: Covid, Chelonians, and a New “Normal”","authors":"Jeffrey A. Seminoff","doi":"10.2744/1071-8443-21.1.1","DOIUrl":"https://doi.org/10.2744/1071-8443-21.1.1","url":null,"abstract":"Here you will find 15 articles with conservation and research efforts reported from seven countries (Australia, Brazil, Cuba, Lao People's Democratic Republic, Philippines, United States, and Venezuela) and data presented for 15 species: Caretta caretta (loggerhead), Chelonia mydas (green turtle), Chelydra serpentina (snapping turtle), Deirochelys reticularia (chicken turtle), Dermatemys mawaii (Central American river turtle), Emydoidea blandingii (Blanding's turtle), Eretmochelys imbricata (hawksbill), Gopherus polyphemus (gopher tortoise), Lepidochelys kempii (Kemp's ridley), Lepidochelys olivacea (olive ridley), Macrochelys suwanniensis (Suwannee alligator snapping turtle), Macrochelys temminckii (alligator snapping turtle), Malayemys khoratensis (Khorat snail-eating turtle), Myuchelys bellii (Bell's turtle), and Siebenrockiella leytensis (Palawan forest turtle). In addition to this diversity of turtle and tortoise species, the research and conservation topics covered in this issue are wide ranging, and include anatomy and physiology, comparative life history analysis, demography and distribution, sea turtle stranding and bycatch research, genetic research, diet analysis, predation abatement strategies, veterinary science, and elaboration of local ecological knowledge.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131672375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Invasive red foxes (Vulpes vulpes) are a serious conservation issue for Australia's freshwater turtle species, including the endangered Bell's turtle (Myuchelys bellii). As many as 96% of Australian freshwater turtle nests may be depredated in a season by foxes. Current methods of turtle nest protection rely on early detection of nesting activity, followed by nest-specific structures to prevent predation. An alternative method to provide protection against fox raiding was tested: nesting refuge structures based on a design successfully used in the United States to protect diamondback terrapin (Malaclemys terrapin) nests. Six wood and chicken wire structures were placed at different sites beside large riverine pools on the Macdonald and Gwydir rivers, northeastern New South Wales, Australia, in the summers of 2019–2020 and 2020–2021. Sites were chosen for known previous nesting activity or presence of mature females, and each structure was placed in typical Bell's turtle nesting habitat at known nesting sites. Prior to placement, the soil was tilled with a rotary hoe to make the interior of the structure more enticing as nesting habitat, because Bell's turtles had been previously seen to nest in disturbed soils. Although females did approach the structures and in one case entered, no females were recorded nesting inside. Further, severe flooding in both years damaged and/or displaced 4 of the 6 structures. Rigid nest protection structures were therefore not shown to be an effective nest protection method for this species, despite their success in other regions for other species. Negative results such as these are important for conservation studies because they guide conservation efforts away from expending limited resources on ineffective methods and strategies.
{"title":"Nesting Refuge Structures Are Ineffective at Protecting Bell's Turtle (Myuchelys bellii) Nests from Red Fox (Vulpes vulpes) Depredation","authors":"Geoffrey N. Hughes, A. Burns, P. Mcdonald","doi":"10.2744/CCB-1507.1","DOIUrl":"https://doi.org/10.2744/CCB-1507.1","url":null,"abstract":"Abstract. Invasive red foxes (Vulpes vulpes) are a serious conservation issue for Australia's freshwater turtle species, including the endangered Bell's turtle (Myuchelys bellii). As many as 96% of Australian freshwater turtle nests may be depredated in a season by foxes. Current methods of turtle nest protection rely on early detection of nesting activity, followed by nest-specific structures to prevent predation. An alternative method to provide protection against fox raiding was tested: nesting refuge structures based on a design successfully used in the United States to protect diamondback terrapin (Malaclemys terrapin) nests. Six wood and chicken wire structures were placed at different sites beside large riverine pools on the Macdonald and Gwydir rivers, northeastern New South Wales, Australia, in the summers of 2019–2020 and 2020–2021. Sites were chosen for known previous nesting activity or presence of mature females, and each structure was placed in typical Bell's turtle nesting habitat at known nesting sites. Prior to placement, the soil was tilled with a rotary hoe to make the interior of the structure more enticing as nesting habitat, because Bell's turtles had been previously seen to nest in disturbed soils. Although females did approach the structures and in one case entered, no females were recorded nesting inside. Further, severe flooding in both years damaged and/or displaced 4 of the 6 structures. Rigid nest protection structures were therefore not shown to be an effective nest protection method for this species, despite their success in other regions for other species. Negative results such as these are important for conservation studies because they guide conservation efforts away from expending limited resources on ineffective methods and strategies.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126920780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Moncada, O. Revuelta, Gonzalo Nodarse, Y. Medina, Anyell Caderno
Abstract. Immature hawksbill turtles were studied in Jardines de la Reina Archipelago, the principal area of distribution for this species in Cuban waters. Hawksbill areas of occurrence, size composition, scope of movement range, and somatic growth rates are presented. A total of 496 individuals were caught while diving or with nets at depths of 0.5–2.5 m. Differences in size distribution were observed among survey areas within the Jardines de la Reina Archipelago. Mean curved carapace lengths were 35.6 ± 9.6 cm and 59.6 ± 7.7 cm for hawksbills captured in the external and internal cays, respectively. Forty-two individuals were recaptured between 1 and 4 times at intervals averaging 554.9 d. For recaptured turtles, 91% were encountered within < 1 km of their original capture location. Our findings indicate that the benthic habitats of Jardines de la Reina Archipelago are favorable for the recruitment of juvenile hawksbill turtles transitioning from pelagic habitats. The data also show that hawksbills are distributed throughout the Jardines de la Reina Archipelago study region, and that coastal foraging areas within this region host small, postpelagic juveniles as well as larger immature hawksbills that have been resident for extended periods.
摘要在Jardines de la Reina群岛研究了未成熟的玳瑁龟，这是该物种在古巴水域的主要分布区域。介绍了玳瑁的发生区域、大小组成、活动范围和躯体生长速度。在0.5-2.5米的深度潜水或用网捕获了496只。在贾丁斯德拉雷纳群岛的调查区域内观察到大小分布的差异。外日和内日捕获的玳瑁平均弯曲甲壳长度分别为35.6±9.6 cm和59.6±7.7 cm。42只海龟在1 - 4次之间被重新捕获，平均间隔554.9 d。在被重新捕获的海龟中，91%的海龟在距离原始捕获地点< 1公里的范围内被捕获。研究结果表明，怡和群岛的底栖环境有利于从远洋生境过渡到幼玳瑁的招募。数据还显示，玳瑁分布在整个怡和群岛的研究区域，该地区的沿海觅食区有小型的、晚期的幼鹰和较大的未成熟的玳瑁，它们在那里居住了很长一段时间。
{"title":"Juvenile Hawksbill Turtles, Eretmochelys imbricata, in the Jardines de la Reina Archipelago, Cuba","authors":"F. Moncada, O. Revuelta, Gonzalo Nodarse, Y. Medina, Anyell Caderno","doi":"10.2744/CCB-1504.1","DOIUrl":"https://doi.org/10.2744/CCB-1504.1","url":null,"abstract":"Abstract. Immature hawksbill turtles were studied in Jardines de la Reina Archipelago, the principal area of distribution for this species in Cuban waters. Hawksbill areas of occurrence, size composition, scope of movement range, and somatic growth rates are presented. A total of 496 individuals were caught while diving or with nets at depths of 0.5–2.5 m. Differences in size distribution were observed among survey areas within the Jardines de la Reina Archipelago. Mean curved carapace lengths were 35.6 ± 9.6 cm and 59.6 ± 7.7 cm for hawksbills captured in the external and internal cays, respectively. Forty-two individuals were recaptured between 1 and 4 times at intervals averaging 554.9 d. For recaptured turtles, 91% were encountered within < 1 km of their original capture location. Our findings indicate that the benthic habitats of Jardines de la Reina Archipelago are favorable for the recruitment of juvenile hawksbill turtles transitioning from pelagic habitats. The data also show that hawksbills are distributed throughout the Jardines de la Reina Archipelago study region, and that coastal foraging areas within this region host small, postpelagic juveniles as well as larger immature hawksbills that have been resident for extended periods.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121874669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-21DOI: 10.2744/1071-8443-21.1.141
{"title":"TURTLE POETRY","authors":"","doi":"10.2744/1071-8443-21.1.141","DOIUrl":"https://doi.org/10.2744/1071-8443-21.1.141","url":null,"abstract":"","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117315789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Traci D. Castellón, B. B. Rothermel, Jennifer L. Beck, J. L. Fort, Kelly M. O’Connor
Abstract. In the southern half of peninsular Florida, where longleaf pine (Pinus palustris) sandhill communities are scarce, gopher tortoises (Gopherus polyphemus) primarily occupy mesic flatwoods and Florida scrub habitats that appear suboptimal due to poorly drained soils in flatwoods and low forage abundance in scrub. Tortoise populations persist in these habitats, but their demography is poorly understood. We used burrow size-class distributions to assess population age structure in flatwoods and scrub habitats. In addition, we monitored tortoise nests and burrows with automated cameras to assess nest fate and visitation by predators. Burrows in flatwoods were strongly skewed toward adult size classes, suggesting low juvenile recruitment, which may be due to poor nest success caused by surface flooding or saturated soils. Size class distributions in scrub were also skewed but were closer to the expected range for a long-lived species with slowed growth following maturity. Rates of predator visitation did not differ between habitats but nests in flatwoods were inundated by heavy rains. More research is needed to clarify the demographics of gopher tortoises in the southernmost extent of their range. However, we suspect that some negative demographic consequences of suboptimal conditions may be offset by the warm climate in southern Florida, which may lengthen the growing season, promoting faster growth and earlier age at first reproduction that could boost population growth.
{"title":"Divergent Size-Class Distributions of Gopher Tortoise Burrows in Scrub and Flatwoods Habitats of Peninsular Florida","authors":"Traci D. Castellón, B. B. Rothermel, Jennifer L. Beck, J. L. Fort, Kelly M. O’Connor","doi":"10.2744/CCB-1523.1","DOIUrl":"https://doi.org/10.2744/CCB-1523.1","url":null,"abstract":"Abstract. In the southern half of peninsular Florida, where longleaf pine (Pinus palustris) sandhill communities are scarce, gopher tortoises (Gopherus polyphemus) primarily occupy mesic flatwoods and Florida scrub habitats that appear suboptimal due to poorly drained soils in flatwoods and low forage abundance in scrub. Tortoise populations persist in these habitats, but their demography is poorly understood. We used burrow size-class distributions to assess population age structure in flatwoods and scrub habitats. In addition, we monitored tortoise nests and burrows with automated cameras to assess nest fate and visitation by predators. Burrows in flatwoods were strongly skewed toward adult size classes, suggesting low juvenile recruitment, which may be due to poor nest success caused by surface flooding or saturated soils. Size class distributions in scrub were also skewed but were closer to the expected range for a long-lived species with slowed growth following maturity. Rates of predator visitation did not differ between habitats but nests in flatwoods were inundated by heavy rains. More research is needed to clarify the demographics of gopher tortoises in the southernmost extent of their range. However, we suspect that some negative demographic consequences of suboptimal conditions may be offset by the warm climate in southern Florida, which may lengthen the growing season, promoting faster growth and earlier age at first reproduction that could boost population growth.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"310 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115911014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Travis M. Thomas, Kevin M. Enge, E. Suarez, Gerald R. Johnston
Abstract. Freshwater megafauna populations, which are declining worldwide, are well known but often overlooked and understudied compared with marine and terrestrial megafauna. One species of freshwater megafauna is the Suwannee alligator snapping turtle (Macrochelys suwanniensis), which is endemic to the Suwannee River drainage in Georgia and Florida. Several trapping studies have examined M. suwanniensis distribution, body size, and population structure, but little information exists regarding its population status. The objectives of our study were to 1) estimate population size, 2) estimate apparent survival, and 3) model population growth rates (k) by conducting a capture–mark–recapture study of M. suwanniensis in the Suwannee River in Florida. From 2011 to 2013, we repeatedly sampled 12 randomly selected 5-km sites along the Suwannee River for M. suwanniensis using baited hoop-net traps. We captured 126 individuals and had 29 recaptures. Both adult males and adult females had very high apparent survival (0.99), whereas juveniles had lower apparent survival (0.32). We estimated a population density of 6.6 turtles/river km, indicating a population of 1709 (95% CI, 1205–2694) M. suwanniensis from the town of White Springs to the upper limit of the estuary in the main stem of the Suwannee River (approximately 259 river km). We constructed 2 postbreeding census matrix population models for M. suwanniensis and incorporated parameters from this study and from the literature. Both matrix population models suggested a slightly decreasing population (k = 0.99), but because of the uncertainty around our estimates, we consider the population trend to be unclear. Elasticity analysis revealed that k was most sensitive to changes in adult survival compared with other model components. This is a conservation concern because adult M. suwanniensis may be incidentally killed by fishing gear. Our study was short-term, and our analyses had limitations; therefore, we recommend future areas of research, including long-term population monitoring.
{"title":"Population Status of the Suwannee Alligator Snapping Turtle (Macrochelys suwanniensis) in the Suwannee River, Florida","authors":"Travis M. Thomas, Kevin M. Enge, E. Suarez, Gerald R. Johnston","doi":"10.2744/CCB-1500.1","DOIUrl":"https://doi.org/10.2744/CCB-1500.1","url":null,"abstract":"Abstract. Freshwater megafauna populations, which are declining worldwide, are well known but often overlooked and understudied compared with marine and terrestrial megafauna. One species of freshwater megafauna is the Suwannee alligator snapping turtle (Macrochelys suwanniensis), which is endemic to the Suwannee River drainage in Georgia and Florida. Several trapping studies have examined M. suwanniensis distribution, body size, and population structure, but little information exists regarding its population status. The objectives of our study were to 1) estimate population size, 2) estimate apparent survival, and 3) model population growth rates (k) by conducting a capture–mark–recapture study of M. suwanniensis in the Suwannee River in Florida. From 2011 to 2013, we repeatedly sampled 12 randomly selected 5-km sites along the Suwannee River for M. suwanniensis using baited hoop-net traps. We captured 126 individuals and had 29 recaptures. Both adult males and adult females had very high apparent survival (0.99), whereas juveniles had lower apparent survival (0.32). We estimated a population density of 6.6 turtles/river km, indicating a population of 1709 (95% CI, 1205–2694) M. suwanniensis from the town of White Springs to the upper limit of the estuary in the main stem of the Suwannee River (approximately 259 river km). We constructed 2 postbreeding census matrix population models for M. suwanniensis and incorporated parameters from this study and from the literature. Both matrix population models suggested a slightly decreasing population (k = 0.99), but because of the uncertainty around our estimates, we consider the population trend to be unclear. Elasticity analysis revealed that k was most sensitive to changes in adult survival compared with other model components. This is a conservation concern because adult M. suwanniensis may be incidentally killed by fishing gear. Our study was short-term, and our analyses had limitations; therefore, we recommend future areas of research, including long-term population monitoring.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130067654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. The alligator snapping turtle (Macrochelys temminckii) has been proposed as a Threatened species under the US Endangered Species Act and is considered Vulnerable by the International Union for the Conservation of Nature. To provide additional markers for conservation genetic studies, we identified 60 potential microsatellite loci, with 38 being polymorphic in M. temminckii, as well as successful cross-amplification of 12 and 32 polymorphic loci in the Suwannee alligator snapping turtle (M. suwanniensis) and Eastern snapping turtle (Chelydra serpentina), respectively. These loci will be useful in genetic studies associated with informing future management decisions for M. temminckii and the other species of Chelydridae.
{"title":"Characterization of Microsatellite Loci for the Alligator Snapping Turtle and Cross-Amplification in Two Chelydrid Species","authors":"Luke Pearson, B. Kreiser, C. Qualls","doi":"10.2744/CCB-1538.1","DOIUrl":"https://doi.org/10.2744/CCB-1538.1","url":null,"abstract":"Abstract. The alligator snapping turtle (Macrochelys temminckii) has been proposed as a Threatened species under the US Endangered Species Act and is considered Vulnerable by the International Union for the Conservation of Nature. To provide additional markers for conservation genetic studies, we identified 60 potential microsatellite loci, with 38 being polymorphic in M. temminckii, as well as successful cross-amplification of 12 and 32 polymorphic loci in the Suwannee alligator snapping turtle (M. suwanniensis) and Eastern snapping turtle (Chelydra serpentina), respectively. These loci will be useful in genetic studies associated with informing future management decisions for M. temminckii and the other species of Chelydridae.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"185 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131714190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Innis, K. Conley, P. Gibbons, N. Stacy, H. Walden, P. Martelli, Sonja Luz, Karthiyani Krishnasamy, Cris Hagen, John M. Sykes, D. Acosta, Kyle Tabug, M. O'Connor, V. V. Wilson, James Liu, Czaba Géczy, Nguyen Thi Thanh Nga, Ihsaan Sebro, Sheena Koeth, S. Lancaster, A. Grioni, S. Schneider, Olivia Vandersanden, Tom Owens, A. Walde, Niño Rey C. Estoya, A. Lee, S. Schoppe
Abstract. In 2015, nearly 4000 critically endangered Palawan forest turtles (Siebenrockiella leytensis) were confiscated on their native island of Palawan in the Philippines after being illegally harvested for the international wildlife trade. Local conservation biologists and an international team of veterinary and husbandry personnel evaluated, treated, and repatriated the majority of turtles (88%) over a 3-mo period. Common pathologic findings included ophthalmic, dermatologic, musculoskeletal, and gastrointestinal lesions, including keratitis, osteomyelitis of the shell and digits, pododermatitis, and colonic nematodiasis. Hemogram results indicated severe leukocytosis in many individuals. Specimens for genetic analysis and molecular diagnostics were archived, and several intact carcasses were established as museum specimens. International collaboration may be required to ensure the confiscation and survival of illegally traded endangered wildlife, with ongoing efforts toward enhancing the law enforcement, husbandry, and veterinary capacity of range country personnel.
{"title":"Veterinary Observations and Biological Specimen Use after a Massive Confiscation of Palawan Forest Turtles (Siebenrockiella leytensis)","authors":"C. Innis, K. Conley, P. Gibbons, N. Stacy, H. Walden, P. Martelli, Sonja Luz, Karthiyani Krishnasamy, Cris Hagen, John M. Sykes, D. Acosta, Kyle Tabug, M. O'Connor, V. V. Wilson, James Liu, Czaba Géczy, Nguyen Thi Thanh Nga, Ihsaan Sebro, Sheena Koeth, S. Lancaster, A. Grioni, S. Schneider, Olivia Vandersanden, Tom Owens, A. Walde, Niño Rey C. Estoya, A. Lee, S. Schoppe","doi":"10.2744/CCB-1510.1","DOIUrl":"https://doi.org/10.2744/CCB-1510.1","url":null,"abstract":"Abstract. In 2015, nearly 4000 critically endangered Palawan forest turtles (Siebenrockiella leytensis) were confiscated on their native island of Palawan in the Philippines after being illegally harvested for the international wildlife trade. Local conservation biologists and an international team of veterinary and husbandry personnel evaluated, treated, and repatriated the majority of turtles (88%) over a 3-mo period. Common pathologic findings included ophthalmic, dermatologic, musculoskeletal, and gastrointestinal lesions, including keratitis, osteomyelitis of the shell and digits, pododermatitis, and colonic nematodiasis. Hemogram results indicated severe leukocytosis in many individuals. Specimens for genetic analysis and molecular diagnostics were archived, and several intact carcasses were established as museum specimens. International collaboration may be required to ensure the confiscation and survival of illegally traded endangered wildlife, with ongoing efforts toward enhancing the law enforcement, husbandry, and veterinary capacity of range country personnel.","PeriodicalId":126915,"journal":{"name":"Chelonian Conservation and Biology: Celebrating 25 Years as the World's Turtle and Tortoise Journal","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126185247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：