Environmental Science › Nature and Landscape Conservation

Turtle Biology and Conservation

Works Count: 29668

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This cluster of papers focuses on the conservation and management of marine turtles worldwide, with an emphasis on understanding the impacts of fisheries bycatch, satellite tracking, climate change, nesting habitat, population dynamics, sea-level rise, thermal conditions, and genetic structure. The research priorities include informing global conservation efforts and addressing the threats faced by marine turtle populations.

Keywords

Marine Turtles; Conservation; Bycatch; Satellite Tracking; Climate Change; Nesting Habitat; Population Dynamics; Sea-Level Rise; Thermal Conditions; Genetic Structure

Size and shape variation in the painted turtle. A principal component analysis.

1960-12-01

Pierre Jolicœur , Mosimann Je

Chemical Signals in Vertebrates

1977-01-01

Dietland Müller‐Schwarze , Maxwell M. Mozell

Reptile Medicine and Surgery

2006-01-01

Douglas R. Mader

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Understanding impacts of fisheries bycatch on marine megafauna

2004-09-18

Rebecca L. Lewison , Larry B. Crowder , Alan Read +1 more

Turtles: Perspectives and Research

1980-02-01

Hobart M. Smith , Marion D. Harless , Henry Morlock

Surveys all aspects of turtle biology ranging from care and management of the turtle used in research to conservation requirements and techniques. Examines the current level of knowledge about turtles, … Surveys all aspects of turtle biology ranging from care and management of the turtle used in research to conservation requirements and techniques. Examines the current level of knowledge about turtles, including evolution, zoogeography, biology, and behavior. Proposes possibilities for future research. Includes techniques for housing, handling, and treating turtles in research situations. Summarizes CNS, sensory systems, and physiological data.

Biology and conservation of Sea Turtles

1997-04-01

Sally E. Solomon , Roger Tippett

Patterns of temperature‐dependent sex determination in turtles

1994-09-15

Michael A. Ewert , Dale R. Jackson , Craig E. Nelson

Abstract Among reptiles that show temperature‐dependent sex determination, sex ratios vary across constant incubation temperatures in ways sufficiently predictable to allow classification into patterns. One common pattern shows low temperatures … Abstract Among reptiles that show temperature‐dependent sex determination, sex ratios vary across constant incubation temperatures in ways sufficiently predictable to allow classification into patterns. One common pattern shows low temperatures yielding only males and high temperatures yielding only females. Another common pattern has low as well as high temperatures yielding only or mostly females and some intermediate temperatures yielding mostly males. Patterns tend to be associated with the direction of sexual dimorphism in adult size, especially for species with strong dimorphism. Pivotal temperatures (those yielding 1:1 sex ratios) within the best‐documented species and genera tend to increase with both latitude and longitude across central and southern North America. These geographic trends probably reflect factors that affect nest temperatures (duration of growing season, insolation, and prevailing amounts of shading by vegetation). Data from a population of the alligator snapping turtle (Macroclemys temminckii) suggest that some embryos are temperature‐independent females because these individuals become females even when they are shifted among male‐producing temperatures during development. These individuals are also more frequent in clutches of small eggs. In this and several other species, no constant incubation temperatures yield more than 75% males. © 1994 Wiley‐Liss, Inc.

A Stage‐Based Population Model for Loggerhead Sea Turtles and Implications for Conservation

1987-10-01

Deborah T. Crouse , Larry B. Crowder , Hal Caswell

Management of many species is currently based on an inadequate understanding of their population dynamics. Lack of age—specific demographic information, particularly for long—lived iteroparous species, has impeded development of useful … Management of many species is currently based on an inadequate understanding of their population dynamics. Lack of age—specific demographic information, particularly for long—lived iteroparous species, has impeded development of useful models. We use Lefkovitch stage class matrix model, based on preliminary life table developed by Frazer (1983), to point to interim management measures and to identify those data most critical to refining our knowledge about the population dynamics of threatened loggerhead sea turtles (Caretta caretta). Population projections are used to examine the sensitivity of Frazer's life table to variations in parameter estimates as well as the likely response of the population to various management alternatives. Current management practices appear to be focused on the least responsive life stage, eggs on nesting—beaches. Alternative protection efforts for juvenile loggerheads,such as using turtle excluder devices (TEDs), may be far more effective.

The Biology of Sea Turtles, Volume I

2017-12-06

Peter L. Lutz , John A. Musick , Jeanette Wyneken +1 more

Physiology as Integrated Systems Amanda Southwood Williard Vision Kerstin A. Fritsches and Eric J. Warrant Natal Homing and Imprinting in Sea Turtles Kenneth J. Lohmann, Catherine M.F. Lohmann, J. Roger … Physiology as Integrated Systems Amanda Southwood Williard Vision Kerstin A. Fritsches and Eric J. Warrant Natal Homing and Imprinting in Sea Turtles Kenneth J. Lohmann, Catherine M.F. Lohmann, J. Roger Brothers, and Nathan F. Putman The Skeleton: An In Vivo View of Structure Jeanette Wyneken Age and Age Estimation in Sea Turtles Larisa Avens and Melissa L. Snover Molecular Genetics of Sea Turtles Michael P. Jensen, Nancy N. FitzSimmons, and Peter H. Dutton Oceanic Habits and Habitats: Dermochelys coriacea Vincent S. Saba Oceanic Habits and Habitats: Caretta caretta Katherine L. Mansfield and Nathan F. Putman Feeding Biology: Advances from Field-Based Observations, Physiological Studies, and Molecular Techniques T. Todd Jones and Jeffrey A. Seminoff Predators, Prey, and the Ecological Roles of Sea Turtles Michael R. Heithaus Exposure to and Effects of Persistent Organic Pollutants Jennifer M. Keller Fisheries Bycatch of Marine Turtles: Lessons Learned from Decades of Research and Conservation Rebecca Lewison, Bryan Wallace, Joana Alfaro-Shigueto, Jeff Mangel, Sara Maxwell, and Elliott Hazen Climate Change and Marine Turtles Mark Hamann, Mariana M.P.B. Fuentes, Natalie C. Ban, and Veronique J.L. Mocellin Free-Ranging Sea Turtle Health Mark Flint Sea Turtle Epibiosis Michael G. Frick and Joseph B. Pfaller Parasites of Marine Turtles Ellis C. Greiner Index

International Union for Conservation of Nature and Natural Resources: The IUCN Amphibia-Reptilia Red Data Book. Part 1: Testudines, Crocodylia, Rhynchocephalia. Compiled by BRIAN GROOMBRIDGE, assisted by LISSIE WRIGHT, of the IUCN Conservation Monitoring Centre. - Published by IUCN, Gland, Switzerland, 426 pages

1983-01-01

Heinz Wermuth

Predicting the Impact of Turtle Excluder Devices on Loggerhead Sea Turtle Populations

1994-08-01

Larry B. Crowder , Deborah T. Crouse , Selina S. Heppell +1 more

In this paper, we modified and updated a stage—based population model for loggerhead sea turtles (Caretta caretta) and used the model to project potential population—level effects of the use of … In this paper, we modified and updated a stage—based population model for loggerhead sea turtles (Caretta caretta) and used the model to project potential population—level effects of the use of turtle excluder devices (TEDs) in trawl fisheries of the southeastern US. We reduced the seven—stage model of Crouse et al. (1987) to a five—stage model and performed sensitivity analyses on the matrix. The most sensitive matrix parameters were those dealing with survival while remaining in a stage, rather than growth from one stage to the next or reproductive output. Population growth rate was most sensitive to survival in the large juvenile stage, followed by small juvenile survival. Large juveniles are the most common size class among stranded dead turtles found on beaches; 70—80% of strandings are thought to be related to trawl fisheries. Simulations of our loggerhead model based on estimated effects of TED regulations on stage—specific survivorship suggested that southeastern US loggerhead populations should increase, but rather slowly. If TEDs were required during the shrimping season in offshore areas only (as they were from 1990 to 1992), 70 yr or more would be required for the simulated population to increase by an order of magnitude. Recent estimates of TED effects from South Carolina strandings data suggest a similar recovery rate. Good compliance with regulations requiring TEDs year—round in all waters could allow the population to increase nearly twice as fast as that expected under the "seasonal offshore" regulations. We also used a Leslie matrix version of the model to illustrate the expected transient response in the numbers of females expected on nesting beaches (due to shifting age—size structures with TED use). Rather than a monotonic increase, we expect an initial increase in the number of nesting females, followed by a leveling off or slight decline (perhaps 10—15 yr from now), followed by another increase. The magnitude of the projected population increase will depend upon the actual increases in stage—specific survivorship due to TED regulations. New, or compensatory, sources of mortality could slow or reverse this projected recovery.

Sexual size dimorphism and sexual selection in turtles (order testudines)

1980-01-01

James F. Berry , Richard Shine

Turtles of the United States and Canada

1995-12-21

Dale R. Jackson , Carl H. Ernst , Jeffrey E. Lovich +1 more

Estimating the Effects of Road Mortality on Turtle Populations

2002-12-01

James P. Gibbs , W. Gregory Shriver

Abstract: Road mortality is suspected to have contributed to widespread population declines in turtles in the United States, a country with exceptionally high turtle diversity. We examined the issue through … Abstract: Road mortality is suspected to have contributed to widespread population declines in turtles in the United States, a country with exceptionally high turtle diversity. We examined the issue through a modeling study that integrated road maps and traffic‐volume data with simulated movements of (1) small‐bodied pond turtles, (2) large‐bodied pond turtles, and (3) terrestrial and semiterrestrial (“land”) turtles. Our model predicted that road networks typical of the northeastern, southeastern, and central regions have the potential to limit land‐turtle populations and, to a lesser extent, populations of large‐bodied pond turtles. Nowhere are populations of small‐bodied pond turtles likely threatened regionally by road mortality. We conclude that the demographic traits of some turtles, in combination with their mobility, may jeopardize population persistence within road networks typical of the eastern and central United States.

Delayed Sexual Maturity and Demographics of Blanding's Turtles (Emydoidea blandingii): Implications for Conservation and Management of Long‐Lived Organisms

1993-12-01

Justin D. Congdon , Arthur E. Dunham , Richard C. van Loben Sels

Abstract: A study of Blanding's turtles conducted during 27 of the last 37 years provided demographic data sufficient to examine how life‐history characteristics may constrain population responses of long‐lived organisms. … Abstract: A study of Blanding's turtles conducted during 27 of the last 37 years provided demographic data sufficient to examine how life‐history characteristics may constrain population responses of long‐lived organisms. Eight independent estimates of annual adult survivorship exceeded 93%. Nest survival was variable and ranged from 0.0 to 63% annually, with a mean of 44% from 1976 to 1984 and 3.3% from 1985 to 1991. Recruitment of juveniles and adults was sufficient to replace individuals estimated to have died during the study. A life table for the population resulted in a cohort generation time of 37 years and required a 72% annual survivorship of juveniles between 1 and 13 years of age to maintain a stable population. Population stability was most sensitive to changes in adult or juvenile survival and less sensitive to changes in age at sexual maturity, nest survival, or fecundity. The results from the present study indicate that life‐history traits of long‐lived organisms consist of co‐evolved traits that result in severe constraints on the ability of populations to respond to chronic disturbances. Successful management and conservation programs for long‐lived organisms will be those that recognize that protection of all life stages is necessary. Programs such as headstarting or protection only of nesting sites, in the absence of programs to reduce mortality of older juveniles and adults, appear to be less than adequate to save long‐lived organisms such as sea turtles and some tortoises. The concept of sustainable harvest of already‐reduced populations of long‐lived organisms appears to be an oxymoron.

Population genetics and phylogeography of sea turtles

2007-10-17

Brian W. Bowen , Stephen A. Karl

Abstract The seven species of sea turtles occupy a diversity of niches, and have a history tracing back over 100 million years, yet all share basic life‐history features, including exceptional … Abstract The seven species of sea turtles occupy a diversity of niches, and have a history tracing back over 100 million years, yet all share basic life‐history features, including exceptional navigation skills and periodic migrations from feeding to breeding habitats. Here, we review the biogeographic, behavioural, and ecological factors that shape the distribution of genetic diversity in sea turtles. Natal homing, wherein turtles return to their region of origin for mating and nesting, has been demonstrated with mtDNA sequences. These maternally inherited markers show strong population structure among nesting colonies while nuclear loci reveal a contrasting pattern of male‐mediated gene flow, a phenomenon termed ‘complex population structure’. Mixed‐stock analyses indicate that multiple nesting colonies can contribute to feeding aggregates, such that exploitation of turtles in these habitats can reduce breeding populations across the region. The mtDNA data also demonstrate migrations across entire ocean basins, some of the longest movements of marine vertebrates. Multiple paternity occurs at reported rates of 0–100%, and can vary by as much as 9–100% within species. Hybridization in almost every combination among members of the Cheloniidae has been documented but the frequency and ultimate ramifications of hybridization are not clear. The global phylogeography of sea turtles reveals a gradient based on habitat preference and thermal regime. The cold‐tolerant leatherback turtle ( Dermochelys coriacea ) shows no evolutionary partitions between Indo‐Pacific and Atlantic populations, while the tropical green ( Chelonia mydas ), hawksbill ( Eretmochelys imbricata ), and ridleys ( Lepidochelys olivacea vs. L. kempi ) have ancient separations between oceans. Ridleys and loggerhead ( Caretta caretta ) also show more recent colonization between ocean basins, probably mediated by warm‐water gyres that occasionally traverse the frigid upwelling zone in southern Africa. These rare events may be sufficient to prevent allopatric speciation under contemporary geographic and climatic conditions. Genetic studies have advanced our understanding of marine turtle biology and evolution, but significant gaps persist and provide challenges for the next generation of sea turtle geneticists.

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Body Temperatures of Reptiles

1965-04-01

Bayard H. Brattstrom

A summary of body temperatures of reptiles has been made on the basis of some 9000 body, air, soil, and water temperatures taken or recorded in the literature for 161 … A summary of body temperatures of reptiles has been made on the basis of some 9000 body, air, soil, and water temperatures taken or recorded in the literature for 161 species of reptiles. The range and mean body temperature for the various groups of reptiles are: tur- tles: 8.0 to 37.8, mean: 28.4; Sphenodon: 6.2 to 18.0, mean: 12.5; American alligator: 26-37, mean: between 32 and 35; snakes: 9.0 to 38.0, mean: 25.6; lizards: 11.0 to 46.4, mean 29.1. There are often specific, generic, and family differences in thermal tolerances and prefer- ences, though some reptiles show wide ranges of thermal tolerance with no preferred body temperature, while others have narrow activity ranges and preferences. With an increase in thermal preference, there is usually an associated increase in the critical thermal maximum. Forms with low thermal preference usually have low critical minima and are usually found in colder areas and in colder seasons than those with high thermal preferences. In terms of their thermoregulatory behavior, reptiles can be grouped into: burrowing forms; aquatic forms not selecting temperatures; aquatic forms selecting temperatures; aquatic forms which bask at surface or on shore; nocturnal thigmothermic forms; nocturnal thigmothermic forms that occasionally bask; diurnal, primarily thigmothermic forms that occa- sionally bask and become crepuscular or nocturnal as hot seasons de- velop; diurnal non-baskers; diurnal limited baskers; and true helio- thermic baskers. Thermoregulation in reptiles is both behavioral (emergence, retreat, selection of temperatures, basking, orientation, postural changes, etc.) and physiological (evaporative cooling, vasomotor responses affecting rates of heating, and cooling, and limited heat production in brooding female Indian pythons).

Climate change and marine turtles

2009-03-13

LA Hawkes , Annette C. Broderick , MH Godfrey +1 more

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 7:137-154 (2009) - DOI: https://doi.org/10.3354/esr00198 REVIEW … ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 7:137-154 (2009) - DOI: https://doi.org/10.3354/esr00198 REVIEW Climate change and marine turtles Lucy A. Hawkes1,4, Annette C. Broderick1, Matthew H. Godfrey2,3, Brendan J. Godley1,* 1Marine Turtle Research Group, Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Tremough Campus, Treliever Road, Penryn, Cornwall TR10 9EZ, UK 2North Carolina Wildlife Resources Commission, 1507 St. Ann Street, Beaufort, North Carolina 28516, USA 3Nicholas School of Environment and Earth Sciences, Duke University Marine Lab, 135 Marine Lab Road, Beaufort, North Carolina 28516-9721, USA 4Present address: School of Biological Sciences, Bangor University, Brambell Building, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK *Corresponding author. Email: [email protected] ABSTRACT: Marine turtles occupy a wide range of terrestrial and marine habitats, and many aspects of their life history have been demonstrated to be closely tied to climatic variables such as ambient temperature and storminess. As a group, therefore, marine turtles may be good indicators of climate change effects on coastal and marine habitats. Despite the small number of species in the taxon and a growing body of research in the field, the evidence base to predict resultant impacts of climate change remains relatively poor. We review the data from peer-reviewed publications to assess the likely impacts of climate change on marine turtles and highlight the types of data that would be most useful for an accurate assessment of future effects. The cumulative indications from these previous studies indicate that future research should focus on: (1) climate change effects on key habitats upon which turtles depend; (2) factors that influence nest site selection; (3) the consequences of skewed primary sex ratios; and (4) the effect of climate change on turtles at sea, for example range shifts and dietary breadth. Although it is too early to give detailed management recommendations, careful protection of coastlines along which turtles nest should be considered, as should the protection of beaches that produce male hatchlings, which may be of increased importance in the future. More active management approaches, for example translocation of eggs to suitable yet vacant nesting beaches, may be necessary to consider under worst-case scenarios. KEY WORDS: Global warming · Sea turtle · Temperature · Sex ratio · Phenology · Range · Conservation management · Sea level rise Full text in pdf format PreviousNextCite this article as: Hawkes LA, Broderick AC, Godfrey MH, Godley BJ (2009) Climate change and marine turtles. Endang Species Res 7:137-154. https://doi.org/10.3354/esr00198Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 7, No. 2. Online publication date: May 14, 2009 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2009 Inter-Research.

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Relocation, repatriation, and translocation of amphibians and reptiles: are they conservation strategies that work?

1992-01-01

C. Kenneth Dodd , Richard A. Seigel

Sex Determination in Reptiles

1980-03-01

James J. Bull

Two factors in reptile sex determination have been studied: (1) the presence or absence of heteromorphic sex chromosomes, and (2) the influence of temperature. Recognizable sex chromosomes are common in … Two factors in reptile sex determination have been studied: (1) the presence or absence of heteromorphic sex chromosomes, and (2) the influence of temperature. Recognizable sex chromosomes are common in snakes and lizards, but are apparently rare in turtles and absent in crocodilians and the tuatara. Temperature-dependent sex determination (TSD) is common in turtles and has been reported in two lizards and alligators; however, data on TSD are available for few non-turtle species. Present findings on TSD suggest that (1) temperature actually determines sex rather than simply causing differential mortality, and (2) temperature controls sex determination in nature as well as in the laboratory. Only one study, however, has convincingly demonstrated the latter. Sex determination by nest temperature is proposed to interfere with the evolution of sex chromosomes and live-bearing (ovoviviparity); a negative correlation should thus be observed between TSD and sex chromosomes/live-bearing. Present evidence is consistent with these predictions. Possible selective advantages and disadvantages of the different sex-determined mechanisms are discussed, and an attempt is made to deduce their ancestries.

Modeling Population Viability for the Desert Tortoise in the Western Mojave Desert

1994-08-01

Daniel F. Doak , Peter Kareiva , Brad Klepetka

The desert tortoise is a threatened species living in the deserts of the American Southwest. Using size—structured demographic models, we analyzed the status of the tortoise in the Western Mojave … The desert tortoise is a threatened species living in the deserts of the American Southwest. Using size—structured demographic models, we analyzed the status of the tortoise in the Western Mojave desert and evaluated the effectiveness of possible management measures. Our demographic analyses agree with the trends reported by field censuses in showing rapid population decline. Importantly, simulations that include variation and correlation in vital rates yield highly variable forecasts of population growth, indicating the uncertainties inherent in even short—term projections of tortoise population sizes. To determine where conservation efforts and data collection should be focused, we performed a series of sensitivity analyses in which the effects of changing different vital rates were quantified. We found that the rate of population growth is most sensitive to the survival of large adult females and that improving survival of this size class to reputably "pristine" rates could reverse population declines; in contrast, large improvements in other vital rates will not, alone, reverse population decline. Thus, shooting, off—road vehicles, upper respiratory tract disease (URTD), and other major sources of adult mortality should be the primary focus of management strategies. Finally, we discuss the impact of the proposed expansion of the U.S. Army's Fort Irwin, which would reduce the Western Mojave tortoise population by ≤13%. We argue that the expansion could have a grave impact on the long—term population viability of the tortoise, but that this impact will be a function of the management of remaining tortoise habitat. We conclude that, although many anthropogenic impacts threaten the tortoise, the species' future could be bright, provided that research and land—use planning focus on biologically important aspects of its life history.

Scaling: Why is Animal Size so Important?

1985-01-01

Georgina M. Mace

Application of Life-History Theory and Population Model Analysis to Turtle Conservation

1998-05-01

Selina S. Heppell

As more reptiles find their way onto endangered species lists, it is increasingly important to identify management alternatives that can be applied across taxa. I have compared life tables from … As more reptiles find their way onto endangered species lists, it is increasingly important to identify management alternatives that can be applied across taxa. I have compared life tables from several turtle populations using elasticity analysis, a method that calculates the proportional contribution of each vital rate (age-specific survival and fecundity) to the annual population multiplication rate, k [In (X) = r, the intrinsic rate of increase]. Most freshwater turtles share similar elasticity patterns across age classes, in spite of large variations in mean annual fecundity, annual survival, and age at maturity. High adult survival elasticity and low fecundity elasticity in these species suggests that conservation efforts that reduce mortality of adults are likely to stabilize declining populations. Desert tortoises and sea turtles had different elasticity patterns, with relatively higher juvenile elasticities when summed across age classes. Three different life tables for painted turtles also showed variation in elasticity patterns. Approximate elasticities can be generated for age-based matrices without a complete life table for each species, requiring only age at maturity, adult female annual survival, and population multiplication rate. This approximation may help identify sensitive life stages for poorly known species, thereby guiding research and management efforts and furthering our understanding of lifehistory patterns.

A series of stages in the embryonic development of Chelydra serpentina

1968-06-01

C. L. Yntema

Abstract Eggs of the common snapping turtle, Chelydra serpentina serpentina were incubated at 30°C and at 20°C. The incubation period at the higher temperature was about 63 days. At the … Abstract Eggs of the common snapping turtle, Chelydra serpentina serpentina were incubated at 30°C and at 20°C. The incubation period at the higher temperature was about 63 days. At the lower temperature, the period was estimated to be 140 days. Lengths of the embryos at various times of development were recorded. A series of 26 stages is described. The staging is based on timed intervals at a constant temperature, 20°C.

Global patterns of marine mammal, seabird, and sea turtle bycatch reveal taxa-specific and cumulative megafauna hotspots

2014-03-17

Rebecca L. Lewison , Larry B. Crowder , Bryan P. Wallace +7 more

Significance Loss of megafauna, termed trophic downgrading, has been found to affect biotic interactions, disturbance regimes, species invasions, and nutrient cycling. One recognized cause in air-breathing marine megafauna is incidental … Significance Loss of megafauna, termed trophic downgrading, has been found to affect biotic interactions, disturbance regimes, species invasions, and nutrient cycling. One recognized cause in air-breathing marine megafauna is incidental capture or bycatch by fisheries. Characterizing megafauna bycatch patterns across large ocean regions is limited by data availability but essential to direct conservation and management resources. We use empirical data to identify the global distribution and magnitude of seabird, marine mammal, and sea turtle bycatch in three widely used fishing gears. We identify taxa-specific hotspots and find evidence of cumulative impacts. This analysis provides an unprecedented global assessment of the distribution and magnitude of air-breathing megafauna bycatch, highlighting its cumulative nature and the urgent need to build on existing mitigation successes.

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Quantifying the effects of fisheries on threatened species: the impact of pelagic longlines on loggerhead and leatherback sea turtles

2004-02-24

Rebecca L. Lewison , Sloan A. Freeman , Larry B. Crowder

Abstract The depletion of fish stocks from global fisheries has been a long‐standing concern. More recently, incidental catch of non‐target (termed bycatch) vertebrates also has been proposed as a serious … Abstract The depletion of fish stocks from global fisheries has been a long‐standing concern. More recently, incidental catch of non‐target (termed bycatch) vertebrates also has been proposed as a serious conservation issue. Here we present a bycatch assessment for loggerhead and leatherback sea turtles that are incidentally caught by global pelagic longlines. We integrate catch data from over 40 nations and bycatch data from 13 international observer programmes. Despite infrequent rates of encounter, our analyses show that more than 200 000 loggerheads and 50 000 leatherbacks were likely taken as pelagic longline bycatch in 2000. Our analyses suggest that thousands of these turtles die each year from longline gear in the Pacific Ocean alone. Given 80–95% declines for Pacific loggerhead and leatherback populations over the last 20 years, this bycatch level is not sustainable. Adopting a large‐scale, synthetic approach is critical to accurately characterize the influence of global fisheries bycatch on globally distributed and imperilled pelagic vertebrates.

Investigating the potential impacts of climate change on a marine turtle population

2007-04-25

Lucy A. Hawkes , Annette C. Broderick , M. H. Godfrey +1 more

Abstract Recent increases in global temperatures have affected the phenology and survival of many species of plants and animals. We investigated a case study of the effects of potential climate … Abstract Recent increases in global temperatures have affected the phenology and survival of many species of plants and animals. We investigated a case study of the effects of potential climate change on a thermally sensitive species, the loggerhead sea turtle, at a breeding location at the northerly extent of the range of regular nesting in the United States. In addition to the physical limits imposed by temperature on this ectothermic species, sea turtle primary sex ratio is determined by the temperature experienced by eggs during the middle third of incubation. We recorded sand temperatures and used historical air temperatures (ATs) at Bald Head Island, NC, to examine past and predict future sex ratios under scenarios of warming. There were no significant temporal trends in primary sex ratio evident in recent years and estimated mean annual sex ratio was 58% female. Similarly, there were no temporal trends in phenology but earlier nesting and longer nesting seasons were correlated with warmer sea surface temperature. We modelled the effects of incremental increases in mean AT of up to 7.5°C, the maximum predicted increase under modelled scenarios, which would lead to 100% female hatchling production and lethally high incubation temperatures, causing reduction in hatchling production. Populations of turtles in more southern parts of the United States are currently highly female biased and are likely to become ultra‐biased with as little as 1°C of warming and experience extreme levels of mortality if warming exceeds 3°C. The lack of a demonstrable increase in AT in North Carolina in recent decades coupled with primary sex ratios that are not highly biased means that the male offspring from North Carolina could play an increasingly important role in the future viability of the loggerhead turtle in the Western Atlantic.

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More than 1000 ultraconserved elements provide evidence that turtles are the sister group of archosaurs

2012-05-16

Nicholas G. Crawford , Brant C. Faircloth , John E. McCormack +3 more

We present the first genomic-scale analysis addressing the phylogenetic position of turtles, using over 1000 loci from representatives of all major reptile lineages including tuatara. Previously, studies of morphological traits … We present the first genomic-scale analysis addressing the phylogenetic position of turtles, using over 1000 loci from representatives of all major reptile lineages including tuatara. Previously, studies of morphological traits positioned turtles either at the base of the reptile tree or with lizards, snakes and tuatara (lepidosaurs), whereas molecular analyses typically allied turtles with crocodiles and birds (archosaurs). A recent analysis of shared microRNA families found that turtles are more closely related to lepidosaurs. To test this hypothesis with data from many single-copy nuclear loci dispersed throughout the genome, we used sequence capture, high-throughput sequencing and published genomes to obtain sequences from 1145 ultraconserved elements (UCEs) and their variable flanking DNA. The resulting phylogeny provides overwhelming support for the hypothesis that turtles evolved from a common ancestor of birds and crocodilians, rejecting the hypothesized relationship between turtles and lepidosaurs.

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Limestone Karsts of Southeast Asia: Imperiled Arks of Biodiversity

2006-01-01

Gopalasamy Reuben Clements , Navjot S. Sodhi , Menno Schilthuizen +1 more

The overexploitation of the world's biomes for natural products calls for the prioritization of biologically important ecosystems for conservation. Here we show that limestone karsts are “arks” of biodiversity and … The overexploitation of the world's biomes for natural products calls for the prioritization of biologically important ecosystems for conservation. Here we show that limestone karsts are “arks” of biodiversity and often contain high levels of endemism. Humans have exploited karsts for a variety of products and services, but unsustainable practices have caused population declines and extinctions among site-endemic taxa. Limestone quarrying is the primary threat to karst biodiversity in Southeast Asia, where quarrying rates exceed those in other tropical regions. Several socioeconomic, political, and scientific issues undermine the stewardship of these karsts. Mitigation of these problems will involve (a) better land-use planning to prevent karst resources from being exhausted in developing regions, (b) comprehensive assessments of a karst's economic and biological value before development, (c) improved legislation and enforcement to protect karst biodiversity, and (d) increased research and activities to promote public awareness of the importance of karsts and the threats facing them.

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Demographics of Common Snapping Turtles (Chelydra serpentina): Implications for Conservation and Management of Long-lived Organisms

1994-06-01

Justin D. Congdon , Arthur E. Dunham , Richard C. van Loben Sels

SYNOPSIS. A study of common snapping turtles conducted from 1975 through 1992 in southeastern Michigan provided sufficient demographic data to examine how life history characteristics may constrain population responses of … SYNOPSIS. A study of common snapping turtles conducted from 1975 through 1992 in southeastern Michigan provided sufficient demographic data to examine how life history characteristics may constrain population responses of long-lived organisms. Females reached sexual maturity between 11 and 16 years of age. Minimum reproductive frequency was less than annual (0.85), and nest survivorship over 17 years ranged from 0 to 64% and averaged 23%. Survivorship of yearlings had to be estimated since hatchlings can pass through the mesh on traps. Actual survivorship of juveniles was over 0.65 by age 2 and averaged 0.77 between the ages of 2 and 12 years. Annual survivorship of adult females ranged from 0.88 to 0.97. A life table for the population resulted in a cohort generation time of 25 years. Population stability was most sensitive to changes in adult or juvenile survival, and less sensitive to changes in age at sexual maturity, nest survival or fecundity. An increase in annual mortality of 0.1 on adults over 15 years of age with no density-dependent compensation would halve the number of adults in less than 20 years. The results from the present study indicate that life history traits of long-lived organisms consist of co-evolved traits that severely constrain the ability of populations to respond to chronic disturbances. Successful management and conservation programs for long-lived organisms will be those that recognize that protection of all life stages is necessary. Without protection of adults and older juveniles, programs that protect nests and headstart hatchlings have a low probability of success. Carefully managed sport harvests of turtles or other long-lived organisms may be sustainable; however, commercial harvests will certainly cause substantial population declines

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Are Diseases Increasing in the Ocean?

2004-11-02

Kevin D. Lafferty , James W. Porter , Susan E. Ford

▪ Abstract Many factors (climate warming, pollution, harvesting, introduced species) can contribute to disease outbreaks in marine life. Concomitant increases in each of these makes it difficult to attribute recent … ▪ Abstract Many factors (climate warming, pollution, harvesting, introduced species) can contribute to disease outbreaks in marine life. Concomitant increases in each of these makes it difficult to attribute recent changes in disease occurrence or severity to any one factor. For example, the increase in disease of Caribbean coral is postulated to be a result of climate change and introduction of terrestrial pathogens. Indirect evidence exists that (a) warming increased disease in turtles; (b) protection, pollution, and terrestrial pathogens increased mammal disease; (c) aquaculture increased disease in mollusks; and (d) release from overfished predators increased sea urchin disease. In contrast, fishing and pollution may have reduced disease in fishes. In other taxa (e.g., sea grasses, crustaceans, sharks), there is little evidence that disease has changed over time. The diversity of patterns suggests there are many ways that environmental change can interact with disease in the ocean.

Life-History Evolution in Reptiles

2005-07-25

Richard Shine

▪ Abstract Two consequences of terrestrial ectothermy (low energy needs and behavioral control of body temperatures) have had major consequences for the evolution of reptile life-history traits. For example, reproducing … ▪ Abstract Two consequences of terrestrial ectothermy (low energy needs and behavioral control of body temperatures) have had major consequences for the evolution of reptile life-history traits. For example, reproducing females can manipulate incubation temperatures and thus phenotypic traits of their offspring by retaining developing eggs in utero. This ability has resulted in multiple evolutionary transitions from oviparity to viviparity in cool-climate reptile populations. The spatial and temporal heterogeneity of operative temperatures in terrestrial habitats also has favored careful nest-site selection and a matching of embryonic reaction norms to thermal regimes during incubation (e.g., via temperature-dependent sex determination). Many of the life-history features in which reptiles differ from endothermic vertebrates—such as their small offspring sizes, large litter sizes, and infrequent reproduction—are direct consequences of ectothermy, reflecting freedom from heat-conserving constraints on body size and energy storage. Ectothermy confers immense flexibility, enabling a dynamic matching of life-history traits to local circumstances. This flexibility has generated massive spatial and temporal variation in life-history traits via phenotypic plasticity as well as adaptation. The diversity of life histories in reptiles can best be interpreted within a conceptual framework that views reptiles as low-energy, variable-temperature systems.

Global research priorities for sea turtles: informing management and conservation in the 21st century

2010-03-16

Mark Hamann , MH Godfrey , JA Seminoff +7 more

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 11:245-269 (2010) - DOI: https://doi.org/10.3354/esr00279 Global … ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 11:245-269 (2010) - DOI: https://doi.org/10.3354/esr00279 Global research priorities for sea turtles: informing management and conservation in the 21st century M. Hamann1, M. H. Godfrey2, J. A. Seminoff3, K. Arthur4, P. C. R. Barata5, K. A. Bjorndal6, A. B. Bolten6, A. C. Broderick7, L. M. Campbell8, C. Carreras9, P. Casale10, M. Chaloupka11, S. K. F. Chan12, M. S. Coyne7,13, L. B. Crowder8, C. E. Diez14, P. H. Dutton3, S. P. Epperly15, N. N. FitzSimmons16, A. Formia17, M. Girondot18, G. C. Hays19, I. J. Cheng20, Y. Kaska21, R. Lewison22, J. A. Mortimer23, W. J. Nichols24, R. D. Reina25, K. Shanker26, J. R. Spotila27, J. Tomás28, B. P. Wallace29,30, T. M. Work31, J. Zbinden32, B. J. Godley7,* 1School of Earth and Environmental Sciences, James Cook University, Townsville, Queensland 4811, Australia 7Marine turtle Research Group, Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Tremough Campus, Treliever Road, Penryn, Cornwall TR10 9EZ, UK *Corresponding author. Email: [email protected] for other authors are given in the electronic supplement at www.int-res.com/articles/suppl/n011p245_supp.pdf ABSTRACT: Over the past 3 decades, the status of sea turtles and the need for their protection to aid population recovery have increasingly captured the interest of government agencies, non-governmental organisations (NGOs) and the general public worldwide. This interest has been matched by increased research attention, focusing on a wide variety of topics relating to sea turtle biology and ecology, together with the interrelations of sea turtles with the physical and natural environments. Although sea turtles have been better studied than most other marine fauna, management actions and their evaluation are often hindered by the lack of data on turtle biology, human–turtle interactions, turtle population status and threats. In an effort to inform effective sea turtle conservation a list of priority research questions was assembled based on the opinions of 35 sea turtle researchers from 13 nations working in fields related to turtle biology and/or conservation. The combined experience of the contributing researchers spanned the globe as well as many relevant disciplines involved in conservation research. An initial list of more than 200 questions gathered from respondents was condensed into 20 metaquestions and classified under 5 categories: reproductive biology, biogeography, population ecology, threats and conservation strategies. KEY WORDS: Sea turtles · Global priorities · Research · Conservation Full text in pdf format Supplementary material PreviousNextCite this article as: Hamann M, Godfrey MH, Seminoff JA, Arthur K and others (2010) Global research priorities for sea turtles: informing management and conservation in the 21st century. Endang Species Res 11:245-269. https://doi.org/10.3354/esr00279Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 11, No. 3. Online publication date: May 26, 2010 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2010 Inter-Research.

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The transition zone chlorophyll front, a dynamic global feature defining migration and forage habitat for marine resources

2001-01-01

Jeffrey J. Polovina , Evan A. Howell , Donald R. Kobayashi +1 more

Global Conservation Priorities for Marine Turtles

2011-09-28

Bryan P. Wallace , Andrew DiMatteo , Alan B. Bolten +7 more

Where conservation resources are limited and conservation targets are diverse, robust yet flexible priority-setting frameworks are vital. Priority-setting is especially important for geographically widespread species with distinct populations subject to … Where conservation resources are limited and conservation targets are diverse, robust yet flexible priority-setting frameworks are vital. Priority-setting is especially important for geographically widespread species with distinct populations subject to multiple threats that operate on different spatial and temporal scales. Marine turtles are widely distributed and exhibit intra-specific variations in population sizes and trends, as well as reproduction and morphology. However, current global extinction risk assessment frameworks do not assess conservation status of spatially and biologically distinct marine turtle Regional Management Units (RMUs), and thus do not capture variations in population trends, impacts of threats, or necessary conservation actions across individual populations. To address this issue, we developed a new assessment framework that allowed us to evaluate, compare and organize marine turtle RMUs according to status and threats criteria. Because conservation priorities can vary widely (i.e. from avoiding imminent extinction to maintaining long-term monitoring efforts) we developed a "conservation priorities portfolio" system using categories of paired risk and threats scores for all RMUs (n = 58). We performed these assessments and rankings globally, by species, by ocean basin, and by recognized geopolitical bodies to identify patterns in risk, threats, and data gaps at different scales. This process resulted in characterization of risk and threats to all marine turtle RMUs, including identification of the world's 11 most endangered marine turtle RMUs based on highest risk and threats scores. This system also highlighted important gaps in available information that is crucial for accurate conservation assessments. Overall, this priority-setting framework can provide guidance for research and conservation priorities at multiple relevant scales, and should serve as a model for conservation status assessments and priority-setting for widespread, long-lived taxa.

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Mitochondrial DNA evolution at a turtle's pace: evidence for low genetic variability and reduced microevolutionary rate in the Testudines.

1992-05-01

John C. Avise , Brian W. Bowen , Trip Lamb +2 more

Evidence is compiled suggesting a slowdown in mean microevolutionary rate for turtle mitochondrial DNA (mtDNA). Within each of six species or species complexes of Testudines, representing six genera and three … Evidence is compiled suggesting a slowdown in mean microevolutionary rate for turtle mitochondrial DNA (mtDNA). Within each of six species or species complexes of Testudines, representing six genera and three taxonomic families, sequence divergence estimates derived from restriction assays are consistently lower than expectations based on either (a) the dates of particular geographic barriers with which significant mtDNA genetic clades appear associated or (b) the magnitudes of sequence divergence between mtDNA clades in nonturtle species that otherwise exhibit striking phylogeographic concordance with the genetic partitions in turtles. Magnitudes of the inferred rate slowdowns average eightfold relative to the "conventional" mtDNA clock calibration of 2%/Myr sequence divergence between higher animal lineages. Reasons for the postulated deceleration remain unknown, but two intriguing correlates are (a) the exceptionally long generation length most turtles and (b) turtles' low metabolic rate. Both factors have been suspected of influencing evolutionary rates in the DNA sequences of some other vertebrate groups. Uncertainities about the dates of cladogenetic events in these Testudines leave room for alternatives to the slowdown interpretation, but consistency in the direction of the inferred pattern, across several turtle species and evolutionary settings, suggests the need for caution in acceptance of a universal mtDNA-clock calibration for higher animals.

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Marine Debris and Human Impacts on Sea Turtles in Southern Brazil

2001-12-01

Leandro Bugoni , Lı́gia Krause , Maria Virgı́nia Petry

Regional Management Units for Marine Turtles: A Novel Framework for Prioritizing Conservation and Research across Multiple Scales

2010-12-17

Bryan P. Wallace , Andrew DiMatteo , Brendan Hurley +7 more

Background Resolving threats to widely distributed marine megafauna requires definition of the geographic distributions of both the threats as well as the population unit(s) of interest. In turn, because individual … Background Resolving threats to widely distributed marine megafauna requires definition of the geographic distributions of both the threats as well as the population unit(s) of interest. In turn, because individual threats can operate on varying spatial scales, their impacts can affect different segments of a population of the same species. Therefore, integration of multiple tools and techniques — including site-based monitoring, genetic analyses, mark-recapture studies and telemetry — can facilitate robust definitions of population segments at multiple biological and spatial scales to address different management and research challenges. Methodology/Principal Findings To address these issues for marine turtles, we collated all available studies on marine turtle biogeography, including nesting sites, population abundances and trends, population genetics, and satellite telemetry. We georeferenced this information to generate separate layers for nesting sites, genetic stocks, and core distributions of population segments of all marine turtle species. We then spatially integrated this information from fine- to coarse-spatial scales to develop nested envelope models, or Regional Management Units (RMUs), for marine turtles globally. Conclusions/Significance The RMU framework is a solution to the challenge of how to organize marine turtles into units of protection above the level of nesting populations, but below the level of species, within regional entities that might be on independent evolutionary trajectories. Among many potential applications, RMUs provide a framework for identifying data gaps, assessing high diversity areas for multiple species and genetic stocks, and evaluating conservation status of marine turtles. Furthermore, RMUs allow for identification of geographic barriers to gene flow, and can provide valuable guidance to marine spatial planning initiatives that integrate spatial distributions of protected species and human activities. In addition, the RMU framework — including maps and supporting metadata — will be an iterative, user-driven tool made publicly available in an online application for comments, improvements, download and analysis.

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Sexual Dimorphism in Turtles with Emphasis on the Slider Turtle (Trachemys scripta)

1990-01-01

J. Whitfield Gibbons , Jeffrey E. Lovich

Sex Determination in Turtles: Diverse Patterns and Some Possible Adaptive Values

1991-02-07

Michael A. Ewert , Craig E. Nelson

New data on the genders of young turtles from eggs incubated at controlled temperatures demonstrate temperature-dependent sex determination (TSD) in 17 species surveyed for the first time and corroborate TSD … New data on the genders of young turtles from eggs incubated at controlled temperatures demonstrate temperature-dependent sex determination (TSD) in 17 species surveyed for the first time and corroborate TSD in another 11 species. The well-known pattern of males from cool temperatures and females from warm ones (=Pattern Ia) occurs in eight species and may occur in seven more. A pattern of cool females, intermediate males, and warm females (=Pattern II) occurs in ten species. Data on three species surveyed for the first time are compatible with genetic sex determination (GSD). Within Clemmys, C. guttata has TSD; C. insculpta, GSD. Comparisons among phylogenetic sister groups suggest at least four independent losses of TSD in turtles. Large variation in extent of sexual differentiation at hatching among TSD species vs GSD species obscures any evidence that either system provides earlier or more complete differentiation. Pattern Ia occurs mainly in species in which adult females average larger than adult males; Pattern II occurs mainly in species with females smaller than males or in which body size is not dimorphic. Among TSD reptiles generally, the smaller gender typically arises at the coolest incubation temperatures. The new data, together with a literature survey, invite four possible explanations for various aspects of sex determination in reptiles: phylogenetic inertia, temperature-dependent differential fitness, sib-avoidance, and group-structured adaptation in sex ratios. Key demographic features from the literature include a high incidence of unisexuality within clutches and a predominance of female biases in sex ratios of hatchlings but not in those of adults. Each of these explanations remains partly but not fully plausible. Explanations for the patterns of sex determination may ultimately require a combination of hypotheses.

Turtles of the United States and Canada

2009-01-01

Carl W. Ernst

Biology and conservation of sea turtles

1997-02-01

Karen A. Bjorndal

Still the most comprehensive review of the subject, Biology and the Conservation of Sea Turtles is now updated to reflect significant advances in sea turtle research. A new section summarizes … Still the most comprehensive review of the subject, Biology and the Conservation of Sea Turtles is now updated to reflect significant advances in sea turtle research. A new section summarizes developments and primary literature for fourteen areas of sea turtle biology and conservation - nesting; hatchling orientation; the early pelagic stage; telemetry and behavior; molecular genetic studies; applied and behavioral endocrinology; metabolism, physiology, and thermoregulation; diseases; temperature and sex ratio; growth and age; population models and structure; the current status of marine turtles worldwide; anthropogenic threats; and headstarting.

Climate change redefines sea turtle hotspots: Vessel strike risks and gaps in protected areas

2025-06-25

Edouard Duquesne , Denis Fournier | Science Advances

Climate change is altering marine ecosystems, driving shifts in sea turtle distributions and challenging conservation efforts. Our study examines how climate change affects the global sea distribution of all seven … Climate change is altering marine ecosystems, driving shifts in sea turtle distributions and challenging conservation efforts. Our study examines how climate change affects the global sea distribution of all seven sea turtle species, intersecting with marine protected areas (MPAs) and shipping corridors. Using species distribution models and environmental data from 2000 to 2024, we project sea turtle habitats under current conditions and three future climate scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5) for 2050 and 2100. Our results show substantial habitat redistributions, with poleward shifts and contractions, particularly under the SSP5-8.5 scenario. Over 50% of sea turtle hotspots may disappear by 2050, with many new habitats in high shipping intensity areas. Alarmingly, only 23% of current hotspots are within MPAs, highlighting the need for adaptive conservation strategies.

Diagnosis and Treatment of an Ununited Anconeal Process in a California Sea Lion (Zalophus californianus)

2025-06-24

Alexander Schlake , Laurens Van Mulders , Merete Klindt Dekkers +6 more | Animals

Orthopedic conditions, congenital or acquired, are frequent reasons for presentation of companion animals to veterinarians [...] Orthopedic conditions, congenital or acquired, are frequent reasons for presentation of companion animals to veterinarians [...]

Assessment of metal distribution patterns in loggerhead sea turtles: A comparative analysis based on sex and tissue type

2025-06-24

Ilker Simsek , Özgür Kuzukıran , İbrahim Filazi +4 more | Marine Pollution Bulletin

Demand for small‐ and large‐ranged reptiles in worldwide wildlife trade

2025-06-24

Songqi Zhang , Shai Meiri , Marcel Holyoak +3 more | Conservation Biology

Abstract Wildlife trade poses a major threat to biodiversity, yet the drivers determining which species are traded are not fully understood. Through a comprehensive collection of official and online trade … Abstract Wildlife trade poses a major threat to biodiversity, yet the drivers determining which species are traded are not fully understood. Through a comprehensive collection of official and online trade data, we applied a binomial test to identify families that contain an unexpectedly large or small number of traded species. We also analyzed which factors predispose reptile species to be traded and explored whether traded species were more likely to be threatened with extinction. Of the 10,919 reptile species in our dataset, 3889 species (35.6%) were traded. There was strong evidence for taxonomic biases in trade risk. In particular, all turtle and crocodilian families had higher trade risk than other reptiles. Species with large body sizes, habitat generalists, insular endemics, and those found in regions with high gross domestic product were traded in greater quantities and more frequently. Species with small and large ranges were more frequently involved in trade, suggesting a demand for rare and common species in wildlife trade. When connecting trade risk to extinction risk, data‐deficient and not‐evaluated species had fewer traded species and were less likely to be traded than threatened or nonthreatened ones. Nonetheless, these species warrant special conservation attention considering their rarity, limited range size, and insufficient legal protection. Given the increased attention given to wildlife trade, we suggest implementing stronger regulatory measures to monitor and control the trade of reptile species, particularly those belonging to families with a high risk of being traded. Efforts should also prioritize the protection of species exhibiting traits that make them highly susceptible to exploitation. Finally, promoting international collaboration for stricter enforcement of wildlife trade regulations and support of sustainable trade practices can help mitigate the negative impacts on biodiversity.

Updated take estimates of marine turtles in the Guajira Peninsula, Venezuela

2025-06-23

Royner Carrasquero-Labarca , Matthew Ware , Jordano Palmar +2 more | Marine and Fishery Sciences (MAFIS)

The Guajira Peninsula is one of the most important foraging grounds areas for marine turtles in Venezuela. There, five species converging: the green turtle, hawksbill, loggerhead, leatherback, and olive ridley. … The Guajira Peninsula is one of the most important foraging grounds areas for marine turtles in Venezuela. There, five species converging: the green turtle, hawksbill, loggerhead, leatherback, and olive ridley. The Wayuú indigenous people are inhabits of the Guajira Peninsula. They have a close relationship with these animals, and for generations, they have used these species as subsistence resources. Marine turtle take has always occurred in this area and has historically been high; it is still happening now, but the current extent is unknown. For that reason, we aim to assess and update the estimate for marine turtles take in the Guajira Peninsula. We conducted 25 field surveys between February and March 2022 by visiting 15 locations to seek for alive turtles and remains on landing sites. We recorded the species, date, location of each encounter, and curve carapace length (CCL) measurements. Additionally, 15 semi-structured interviews were conducted with members of the Wayuú community. During field surveys, an estimated 81 marine turtles were identified. The most affected species were green turtles (91.3%, n = 74), followed by hawksbills (3.7%, n = 3), loggerheads (3.7%, n = 3), and leatherbacks (1.2%, n = 1). The majority of green turtles were subadults, with an average CCL size of 64.7 ± 16.5 cm (82.2%, n = 52). Interviewees mentioned that marine turtles were caught for cultural practices, consumption, ancient medicine, and commerce. Further monitoring activities are needed to understand the take level and its implications for marine turtle populations in the Caribbean Basin.

Retrospective study on the casuistry of turtles (Reptilia: Testudines) in a veterinary center in Paraguay

2025-06-23

Joerg Richard Vetter Hiebert , Sofía B. Clay D. | Veterinaria México OA

Ten turtle species have been reported for Paraguay, and eight of them are in threatened categories. Wildlife commerce is strictly regulated, and according to the most recent data, there is … Ten turtle species have been reported for Paraguay, and eight of them are in threatened categories. Wildlife commerce is strictly regulated, and according to the most recent data, there is no legal way of acquiring a turtle in the country. The objective of this study is to report the species of turtles that were assisted at the Wild and Exotic Animals Clinic of the Facultad de Ciencias Veterinarias, Universidad Nacional de Asunción, and the main clinical findings. Patient files from 2004 to 2023 were reviewed, and the following data were registered in a spreadsheet: file number and date, species, weight, sex, approximate age, origin, time with the person, feeding, diagnosis, and sub-classification. A total of 496 turtles were registered in individual patient files. Of these, 256 were Chelonoidis chilensis, 125 C. carbonaria, 4 unknown Chelonoidis spp., 8 Acanthochelys macrocephala, 1 A. pallidipectoris, 7 Mesoclemmys vanderhaegei, 6 Phynops spp. (3 P. hilarii, 2 P. geoffroanus, 1 unknown), 2 Hydromedusa tectifera, 14 Kinosternon scorpioides, and 12 unknown Pleurodira. Regarding casuistry, of the 256 C. chilensi brought to the practice, the main cause of consultation was trauma, representing 130 (50.78 %) of the registered files for the species. Regarding C. carbonaria, of the 125 cases, 26 were related to trauma, although routine control was the main cause of consultation. This constitutes the first report on turtle casuistry in Paraguay and may aid in identifying critical species to work with, while concluding that the main problem is still illegal traffic.

Growth rates of the epibiotic barnacle Chelonibia testudinaria reveal habitat use of pre-nesting green turtles in Costa Rica

2025-06-23

Sergio Poyatos , Pilar Santidrián Tomillo , Lara Fazzari +4 more | Marine Biology

Abstract The barnacle Chelonibia testudinaria is arguably the most common and conspicuous epibiont on sea turtles. As evidence suggests that C. testudinaria settles on turtles in coastal areas, this barnacle … Abstract The barnacle Chelonibia testudinaria is arguably the most common and conspicuous epibiont on sea turtles. As evidence suggests that C. testudinaria settles on turtles in coastal areas, this barnacle could serve as an indicator of habitat use. The utility of C. testudinaria for this purpose is, however, limited by a lack of information on its growth rate. Here, we estimated growth curves for C. testudinaria on green turtles ( Chelonia mydas ) nesting on Cabuyal (10° 40 N, 85° 39 W) and Playa Grande/Ventanas (10° 20 N, 85° 51 W) in northwest Costa Rica. Growth rates of 106 barnacles from 38 green turtles were measured during the 2023/24 turtle nesting season and then incorporated into a von Bertalanffy growth model. The mean intrinsic growth rate (rostro-carinal length) was 0.0091 d −1 and the asymptotic length was 59.5 mm. We detected a statistically significant effect of beach and turtle identity on growth rates, and growth rates were almost double those reported from C. testudinaria on loggerhead turtles in Australia. Our results indicate that barnacle larvae settled a mean of 76 d before turtles begin nesting, and thus pre-nesting turtles likely also inhabit coastal habitats. In addition, we provide the first measurements of barnacle detachment rates in wild sea turtles with 24.1% of barnacles detaching after a single internesting period (9–21 d). Our study reinforces the utility of C. testudinaria as indicators of coastal habitat use in sea turtles, although further studies into the variables driving barnacle growth are still required.

Ficha de Serrapinnus aster

2025-06-23

André Luiz Henriques Esguícero , André Luiz Netto Ferreira , Bruno Francelino de Melo +7 more | Datasets - Sistema SALVE - ICMBio

Changes in food-derived minerals and molecules during different growth phases of freshwater tortoise (Geochelone nigra) under intensive management system: implication for public health

2025-06-21

J. I. Kperegbeyi , O. E. OKHALE , Onyinye S. Onwumere-Idolor +2 more | International Journal of Scientific Reports

Background: Freshwater tortoises (Geochelone nigra) are the most popular in the rainforest region. Their growth phases include hatchling growth phase (HGP), juvenile growth phase (JGP), sub-adult growth phase (SAGP) and … Background: Freshwater tortoises (Geochelone nigra) are the most popular in the rainforest region. Their growth phases include hatchling growth phase (HGP), juvenile growth phase (JGP), sub-adult growth phase (SAGP) and adult growth phase (AGP). Objective of the study was to investigate the impact of minerals value on the different growth phases of the Nigerian freshwater tortoise. Methods: This was an observational comparative study. The HGP, JGP, SAGP and AGP comprised four groups. 5-serial blood samples taken every two-months. The Ca2+, Cl-1, Na+, and PO4-2 were assessed as minerals; while blood glucose, lipids and proteins comprised food-derived molecules. Comparison was by simple ANOVA. Results: Highest concentration of glucose and lipids were recorded at the SAGP (72.00 mg/dl and 64.10 mg/dl); while the concentration of protein showed gradient increase as the tortoises progressed from HGP to AGP. Growth phases significantly (p˂0.05) differed in the mineral composition of the tortoises with SAGP showing highest values in Ca2+, PO4-2 and Na+. Conclusions: SAGP of Geochelone nigra has better serum biochemical values than HGP, JGP and AGP. This finding can be used to inform choice of the growth of tortoise when considering consumption and the desired relative nutritional value. Further implication on recreational and farmed are addressed.

Staphylococcus aureus and methicillin-resistant Staphylococcus aureus in juvenile green turtle (Chelonia mydas) carcasses, rearing seawater, feed and their antibiotic resistances

2025-06-20

Thanaporn Chuen‐Im , Korapan Sawetsuwannakun , Thongchai Taechowisan +1 more | PeerJ

Staphylococcus aureus is an opportunistic bacterium that can infect humans and animals. We previously reported that Staphylococcus aureus as one of the most frequent Gram-positive bacteria found in the infection … Staphylococcus aureus is an opportunistic bacterium that can infect humans and animals. We previously reported that Staphylococcus aureus as one of the most frequent Gram-positive bacteria found in the infection in juvenile green turtles (Chelonia mydas) from the Sea Turtle Conservation Center of Thailand (STCCT), Sattahip, Chonburi Province. It was also the most detected Gram-positive bacteria in rearing seawater. In this study, we investigated the presence of S. aureus in coastal seawater used as supply water to rearing containers, rearing water, fish fillet used as feed, and juvenile green turtle carcasses at STCCT. From the results, S. aureus can be isolated from rearing water, fish fillet, and juvenile turtle carcasses but not from incoming coastal seawater. The determination of antibiotic resistance against 11 drugs demonstrated that more S. aureus from juvenile turtles were antibiotic resistant than the isolates from rearing water and fish fillet. Furthermore, a higher isolate number of methicillin-resistant S. aureus (MRSA) was found in juvenile turtle carcasses. We also detected penicillin-susceptible MRSA and mecA-positive methicillin-susceptible S. aureus from juvenile turtles and fish fillet, respectively. Differences in the antibiotic resistance profiles were observed in this study compared with our previous observation. A change in the antibiotic resistance properties possibly continued in S. aureus. This finding suggests that the status of animal health is at high risk and emphasizes the need for a surveillance plan and treatment strategies to confront this serious threat.

Different growth responses to feed ration levels in two freshwater turtle juveniles, the Chinese three-keeled pond turtle Mauremys reevesii and the red-eared slider Trachemys scripta elegans

2025-06-19

Changyi Zhang , Shufen Jiang , Xinyue Liu +2 more | Aquaculture Reports

Trionychian turtles from the Early Miocene (Burdigalian) Moghra Formation, Egypt, including a new species of Carettochelyidae

2025-06-19

Yann Rollot , Mohamed K. AbdelGawad , Mohamed A. Hamdan +3 more | Swiss Journal of Palaeontology

Although trionychians have a rich fossil record, much of their fossil diversity is known from the Cretaceous and Paleogene, and little is known about their evolutionary history in the Neogene. … Although trionychians have a rich fossil record, much of their fossil diversity is known from the Cretaceous and Paleogene, and little is known about their evolutionary history in the Neogene. We here describe cranial and shell material of trionychians from the Early Miocene Moghra Formation of Egypt that we attribute to a new carettochelyid taxon, Allaeochelys meylani sp. nov., and to the Trionyx lineage. Allaeochelys meylani sp. nov. fills a temporal gap between previously described taxa and exhibits a series of unique features, including greatly thickened cranial bones, a broad bony wall posterior to the orbit, a large fossa formed by the maxilla and premaxilla at the anterior third of the triturating surface, and a medial process on peripheral II. Allaeochelys meylani sp. nov. also documents the oldest occurrence of Carettochelyidae on the Afro-Arabian continent, while the Trionyx material reported herein provides unambiguous evidence for the presence of this lineage on the Afro-Arabian continent no later than the Early Miocene.

The Incubation Environment Shapes the Inflammatory Response and Enables Expression of Maternal Effects on Sea Turtle Hatchling Body Size

2025-06-19

Irma Yunuen García‐Bucio , Bryan V. Phillips-Farfán , Sandra Nataly Chávez‐Salazar +6 more | Integrative Zoology

ABSTRACT Female turtles are believed to select nesting sites that optimize conditions for egg development and allocate resources accordingly. Although relocating clutches to shaded hatcheries enhances hatchling survival, growth, and … ABSTRACT Female turtles are believed to select nesting sites that optimize conditions for egg development and allocate resources accordingly. Although relocating clutches to shaded hatcheries enhances hatchling survival, growth, and immune configuration, the impact of these unexpected environments on maternal investment remains uncertain. Herein, the effects of maternal (body size, as well as hematological and biochemical indicators) and environmental (sand temperature and moisture in both unshaded and shaded nests) variables on local inflammation after a challenge (as a proxy of immune function) and offspring size were evaluated using a split‐clutch design. The association of maternal parameters with reproductive investment, as well as the relationship of incubation conditions to survival indicators (hatching and emergence success), was also evaluated. Hatchlings from shaded nests showed less intense inflammation and were heavier and longer compared to offspring from unshaded conditions. The incubation conditions influenced inflammation in hatchlings, as well as their body mass, straight carapace width, and survival. Maternal leukocytes differentially interacted with the environment to determine hatchling length. Maternal amylase and creatinine concentrations were related to clutch size and mass, respectively, while shading enhanced survival indicators. The results indicate that the incubation condition is the primary factor influencing hatchling phenotypes, both directly and indirectly by facilitating the expression of maternal effects. These findings suggest that while optimal environmental conditions and maternal quality do not synergize to enhance offspring fitness, environmental conditions can override the effects of maternal investment. This highlights the relevance of the incubation environment to guarantee hatchling phenotypes.

Seed Dispersal Effectiveness of Chelonoidis carbonarius and C. denticulatus Tortoises Is Mediated by Body Size and Sex‐Differences in Tortoise Movement

2025-06-19

Joel N. Strong , James P. Gibbs , Reinaldo Imbrózio Barbosa +1 more | Biotropica

ABSTRACT Red‐footed ( Chelonoidis carbonarius ) and yellow‐footed tortoises ( C. denticulatus ) are highly frugivorous, terrestrial chelonians found throughout the Neotropics. We investigated the role of these tortoises as … ABSTRACT Red‐footed ( Chelonoidis carbonarius ) and yellow‐footed tortoises ( C. denticulatus ) are highly frugivorous, terrestrial chelonians found throughout the Neotropics. We investigated the role of these tortoises as seed dispersers in plant communities in the northern Brazilian region of the Amazon Basin. We analyzed movement patterns of radio‐ and thread‐tracked individuals, estimated gut retention time of seeds in captive tortoises, and analyzed fecal samples for abundance, diversity, and viability of seeds. Our results show tortoises to be effective seed dispersers: of 113 fecal samples examined, 92% contained seeds of 19 plant species. Seeds of 17 of these species were viable. Fecal clumps averaged 2.2 species (range 0–5) per unit with a median of 102 seeds per sample (range 0–1140). Larger‐bodied tortoises dispersed more seeds. Integrating these data through movement simulations revealed that long gut retention times for seeds (10–28 days), combined with mean daily tortoise displacements of 103 m, generate seed shadow curves that peak between 300 m (female tortoises) and 400 m (male tortoises) and extended beyond 1 km from the seed source. This study demonstrates differential disperser effectiveness as a result of tortoise size and differences in movement patterns between sexes.

Using accelerometers for tracking loggerhead and green sea turtle behaviour

2025-06-18

Jessica Harvey‐Carroll , Dáire Carroll , José Luis Crespo‐Picazo +2 more | Animal Biotelemetry

Non-invasive DNA analysis combats the illegal trafficking of hawksbill turtle shell products

2025-06-18

Zibin Liang , Jian Chen , Tong Shan +2 more | Conservation Genetics Resources

Sea turtle (Testudines: Cheloniidae) strandings and rehabilitation in Northern Cyprus

2025-06-18

Iona Shearer , Rianne Pelgrims , Wayne J. Fuller +4 more | Zoology in the Middle East

Relationships of corticosterone and thyroxine with mortality, mass gain, feeding and activity in Kemp’s ridley sea turtles (Lepidochelys kempii) recovering from cold-stunning

2025-06-18

Kathleen E. Hunt , Elizabeth A. Burgess , Constance Merigo +7 more | PLoS ONE

Mass strandings of juvenile Kemp’s ridley sea turtles ( Lepidochelys kempii ) occur annually on the shores of Cape Cod, Massachusetts, USA, during the months of Oct-Dec. Strandings have increased … Mass strandings of juvenile Kemp’s ridley sea turtles ( Lepidochelys kempii ) occur annually on the shores of Cape Cod, Massachusetts, USA, during the months of Oct-Dec. Strandings have increased from dozens to hundreds per year in the past two decades, challenging recovery and management of this critically endangered species. Most stranded turtles are suffering from “cold-stunning”, a life-threatening hypothermia-like condition, and are brought to nearby marine animal veterinary clinics for treatment and rehabilitation. Though most individuals survive, some mortality does occur, and even among surviving turtles there can be prolonged deficits in health and behavior. Previous studies have indicated that upon admission, the adrenal stress hormone corticosterone is elevated approximately an order of magnitude above presumed baseline, while plasma thyroxine is often undetectable, suggesting that these two hormones show promise as markers of recovery from cold-stunning. In this prospective study, 106 cold-stunned Kemp’s ridleys were monitored during rehabilitation, with serial blood sampling at 0, 3, 7, 18, 30, 60 and 80 days post-admission to compare plasma concentrations of corticosterone and thyroxine to mortality, mass gain, feeding and activity. Corticosterone and thyroxine normalized in 88% of turtles by approximately day 18, but 12% showed persistent elevations of corticosterone (typically 2-3x above baseline), and persistently low thyroxine. Elevated corticosterone at day 18 was found to be predictive of mortality after day 18. The endocrine profile of high corticosterone and low thyroxine is also associated with lower rates of gain in body mass over time and reduced feeding. As prolonged deficits in growth affect body size at release, low mass gain may affect the predation risk on these juvenile turtles subsequent to release. These results suggest that endocrine biomarkers are useful for monitoring recovery of turtles in rehabilitation, and that growth rates and mass gains during rehabilitation may warrant further investigation.

Microbial Enrichments Contribute to Characterization Of Desert Tortoise Gut Microbiota

2025-06-17

Elaina M. Blair , Noa J Margalith , Michelle O’Malley | Microbial Ecology

Estimating abundance of aggregated populations with drones while accounting for multiple sources of errors: A case study on the mass nesting of Giant South American River Turtles

2025-06-17

Ismael Verrastro Brack , Denis Valle , Camila R. Ferrara +3 more | Journal of Applied Ecology

Abstract Counting animals when populations are spatially aggregated (e.g., breeding or nesting colonies, stopover or haul‐out sites) enhances the accuracy and efficiency of survey efforts for abundance estimation. Orthomosaics generated … Abstract Counting animals when populations are spatially aggregated (e.g., breeding or nesting colonies, stopover or haul‐out sites) enhances the accuracy and efficiency of survey efforts for abundance estimation. Orthomosaics generated from drone images are commonly used to count aggregated populations, but these counts are subject to detection errors that are often overlooked in abundance estimation. Motivated by the need for a monitoring protocol for mass nesting events of Giant South American River Turtles ( Podocnemis expansa ), we develop a novel modelling approach to estimate the abundance of spatially aggregated wildlife populations using drone‐based counts in orthomosaics while accounting for multiple sources of error. We use a combination of mark‐resight data and overall population counts to account for: (i) open population during the nesting event; (ii) individuals unavailable for detection during flight; (iii) double counts due to the orthomosaic building process; (iv) marked individuals detected in the mosaic with unidentifiable marks. From the mark‐resight data, we estimated that the daily nesting probability is 0.37, and that 35% of the individuals that used the sandbank during the night are present during the morning drone flight. We also found that 20% of the turtles walking in the orthomosaic are double counts, and that the probability of identifying the mark in the carapace is 0.78. The total population size was estimated as ~41,000 turtles for the 12 days of nesting season, marking the current world's largest known aggregation of freshwater turtles. By comparing our approach with an abundance estimate based on a simpler model and with visual ground counts, we demonstrate the benefit of our approach and the importance of accounting for the multiple sources of error when counting animals in orthomosaics. Synthesis and applications . The developed approach can be applied to several contexts to efficiently survey spatially aggregated populations using drone‐derived orthomosaics, and to understand phenology at these aggregation sites. We provide general recommendations for planning surveys and discuss implementations of our approach using other types of marking methods and model assumptions.

Monitoring the conservation status of sea turtle nesting sites: expert knowledge and quantitative indicators

2025-06-16

Paolo Casale , Thomas Arapis , Simona A. Ceriani +7 more | Journal of Coastal Conservation

Short-term movements of the Pig-Nosed Turtle (Carrettochelys insculpta) in the Kao River, South Papua, Indonesia

2025-06-15

Morgan Wayne Luther Sawaki , Mirza Dikari Kusrini , Lilik Budi Prasetyo +1 more | Jurnal Pengelolaan Sumberdaya Alam dan Lingkungan (Journal of Natural Resources and Environmental Management)

Understanding animal movement is essential for assessing species' ecological needs and informing effective conservation strategies. This study investigates the short-term daily movement and home range of the Endangered (EN) pig-nosed … Understanding animal movement is essential for assessing species' ecological needs and informing effective conservation strategies. This study investigates the short-term daily movement and home range of the Endangered (EN) pig-nosed turtle (Carettochelys insculpta) in the Kao River, Boven Digoel District, South Papua, Indonesia. Native to Papua New Guinea, Northern Australia, and Southern Papua, this freshwater turtle faces heavy egg harvesting pressure. Using low-cost GPS tracking devices, we monitored six adult individuals (one male and five females) over a three-day period during November–December 2023. The results indicated that the daily movements of C. insculpta ranged from 84.95 to 648.77 m. Average home range estimates were 18.03 ha (minimum convex polygon), 7.51 ha (50% kernel density), and 12.44 ha (95% kernel density). The movement overlaps among the four turtles totaled 30.64 ha, with an average overlap of 6.12 ha. The hotspot analysis identified 76.16 ha as key movement areas, revealing that the pig-nosed turtles tend to stay near sandbanks, primary dryland forest, secondary dryland forest, and shrublands. Our studyprovides important baseline ecological data that can be used to inform future conservation and recovery programs. Elaboration between stakeholders and the local community can be carried out to protect the species.

Short-term movements of the Pig-Nosed Turtle (Carrettochelys insculpta) in the Kao River, South Papua, Indonesia

2025-06-15

Morgan Wayne Luther Sawaki , Mirza Dikari Kusrini , Lilik Budi Prasetyo +1 more | Jurnal Pengelolaan Sumberdaya Alam dan Lingkungan (Journal of Natural Resources and Environmental Management)

First record of Kathlania leptura (Rudolphi, 1819) and Tonaudia tonaudia (Lane, 1914) (Nematoda) in a loggerhead sea turtle (Caretta caretta) from the Eastern Mediterranean, Türkiye

2025-06-13

Gökhan Eren , Mahmut YILMAZ , Mario Santoro | Veteriner Hekimler Derneği Dergisi

The Aegean and Mediterranean coasts of Türkiye are home to the most important feeding, breeding and nesting areas in the Mediterranean for the migratory loggerhead sea turtles (Caretta caretta). These … The Aegean and Mediterranean coasts of Türkiye are home to the most important feeding, breeding and nesting areas in the Mediterranean for the migratory loggerhead sea turtles (Caretta caretta). These sea turtles, which are carnivorous and have a complex life cycle, attract attention with their population density in the Mediterranean and are being investigated parasitologically. The material of this case report submitted consists of nematode specimens obtained from the gastrointestinal tract of a stranded adult female loggerhead sea turtle during necropsy. Two species of kathlanid nematodes (Kathlania leptura and Tonaudia tonaudia) are reported from the small intestine of a loggerhead sea turtle Caretta caretta, found stranded on Demre Beach (Antalya), Türkiye, in August 2024. Both species represent new locality records for Türkiye and in general for the Eastern Mediterranean. In addition, necropsy revealed that the potential cause of death was malnutrition due to two fish hooks penetrating the esophagus and intestinal plication caused by fishing line traction. In conclusion, this study is the first detailed parasitological report on sea turtles in Türkiye and will set an example for future research.

Are Painted Turtles (Chrysemys picta) Resilient to the Potential Impact of Climate Change on Vitamin D via Overgrown Floating Vegetation?

2025-06-12

Nicholas E. Topping , Nicole Valenzuela | Diversity

Floating aquatic vegetation and algal blooms are increasing with global warming, potentially reducing UVB exposure and, consequently, vitamin D (vit-D) synthesis in freshwater turtles. Vit-D mediates calcium metabolism and overall … Floating aquatic vegetation and algal blooms are increasing with global warming, potentially reducing UVB exposure and, consequently, vitamin D (vit-D) synthesis in freshwater turtles. Vit-D mediates calcium metabolism and overall health, yet the effects of floating aquatic vegetation on vit-D levels remain unclear, as is whether turtles actively avoid habitats with abundant floating vegetation. Here, we address these questions by quantifying vit-D3 levels in the blood of adult female painted turtles (Chrysemys picta) exposed to high-vegetation (darker/colder) or clear-water (lighter/warmer) treatments for one month outdoors and one month indoors at a single temperature during late summer and early fall. The observed circulating vit-D3 levels resembled those reported for other freshwater turtles, declined over time in both treatments, and were marginally lower under high vegetation after 60 days compared to clear water. However, this difference disappeared after correcting for lymph contamination and multiple comparisons, suggesting that perhaps adult females are robust to the effect of floating vegetation, but whether they were buffered by vit-D3 stores in lipids is unclear. Additionally, in subsequent years, females were exposed to habitat choice experiments and exhibited a strong preference for high floating vegetation over clear water, both as a group (outdoors) and individually (outdoors, and indoors at 21 °C and 26 °C), consistent with known benefits conferred by floating vegetation (food, predator avoidance). While no ill effects of high vegetation nor behavioral avoidance were detected here, longer experiments at different seasons on both sexes and varying ages are warranted before concluding whether painted turtles are truly resilient in their vit-D levels or if, instead, a tradeoff exists between the known benefits of floating vegetation and potential [yet unidentified] detrimental effects (lower dissolved oxygen or vit-D) when vegetation is overgrown for extended periods.

Hoja informativa sobre la vida silvestre de la Florida: Tortuga Terrestre de Florida

2025-06-06

Bethany Wight , Raoul K. Boughton , Martin B. Main +3 more | EDIS

Esta es una hoja informativa sobre la vida silvestre de Florida dedicada al tortuga terrestre de Florida. Esta ficha busca informar sobre las características de este animal, la historia de … Esta es una hoja informativa sobre la vida silvestre de Florida dedicada al tortuga terrestre de Florida. Esta ficha busca informar sobre las características de este animal, la historia de su presencia en el estado, su distribución actual, biología y comportamiento. El objetivo es informar al público en general sobre esta especie.

Ficha de Catoprion absconditus

2025-06-05

André Luiz Netto Ferreira , Bruno Francelino de Melo , Cárlison Silva de Oliveira +7 more | Datasets - Sistema SALVE - ICMBio