Kemp's Ridley Turtles Research Articles

Modelling drift of cold-stunned Kemp's ridley turtles stranding on the Dutch coast.

Every few years, juvenile Kemp's ridley turtles ( Lepidochelys kempii) are stranded on the Dutch coasts. The main population distribution of this critically endangered species primarily inhabits the Gulf of Mexico and the east coast of the United States. This study focuses on five reports from the Netherlands between 2007 and 2022, where juvenile turtles were reported to strand alive during the winter, albeit in a hypothermic state. At ambient ocean temperatures between 10°C and 13°C, Kemp's ridley turtles begin to show an inability to actively swim and remain afloat on the ocean's surface, a condition termed 'cold stunning'. Understanding their transport in cold-stunned state can help improve the rehabilitation process of stranded turtles. Cold-stunned turtles are back-tracked as passive, virtual particles from their stranding location using Lagrangian flow modelling. This study investigates when and where these juvenile turtles cross the threshold temperatures between 10° C and 14° C before stranding by tracking the temperature along the trajectories. As expected, the simulations show the transport of the cold-stunned turtles via the English Channel. More surprisingly, the analysis suggests they likely experience cold-stunning in the southern North Sea region and encounter temperatures below 10°C for only a few days to up to three weeks, and below 12°C for up to a month before stranding. The estimate of cold-stunned drift duration of the turtles provides additional knowledge about their health status at the time of stranding. Adherence to rehabilitation protocols for Kemp's ridley and post-release monitoring are recommended to improve their long-term survival.

Modelling drift of cold-stunned Kemp's ridley turtles stranding on the Dutch coast

Background Every few years juvenile Kemp’s ridley turtles (Lepidochelys kempii) are found stranded on the Dutch coasts. The main population distribution of this critically endangered species primarily inhabits the Gulf of Mexico and east coast of the United States. This study focuses on five reports from the Netherlands over the past 15 years, where juvenile turtles were reported to strand alive during the winter, albeit in a hypothermic state. Between ambient ocean temperatures of 10°C and 13°C, Kemp’s ridley turtles are unable to actively swim and remain afloat on the ocean’s surface, a condition termed ‘cold stunning’. Understanding their transport in cold-stunned state can help improve the rehabilitation process of stranded turtles. Methods Cold-stunned turtles are back-tracked as passive, virtual particles from their stranding location using Lagrangian flow modelling. This study investigates when and where juveniles of the Kemp's ridley turtles cross the threshold temperatures between 10–14° C before stranding by tracking the temperature along the trajectories. Results As expected, the simulations show transport of the turtles to the Dutch coast via the English Channel. More surprisingly, the analysis suggests that they likely experience cold-stunning in the southern North Sea region and encounter temperatures below 10°C for only a few days to up to three weeks, and below 12°C for up to a month before stranding. Conclusions Adherence to rehabilitation protocols for Kemp’s ridley and monitoring individuals post-release are recommended to improve their long-term survival.

Isotopic niche overlap among foraging marine turtle species in the Gulf of Mexico.

Sympatric species may overlap in their use of habitat and dietary resources, which can increase competition. Comparing the ecological niches and quantifying the degree of niche overlap among these species can provide insights into the extent of resource overlap. This information can be used to guide multispecies management approaches tailored to protect priority habitats that offer the most resources for multiple species. Stable isotope analysis is a valuable tool used to investigate spatial and trophic niches, though few studies have employed this method for comparisons among sympatric marine turtle species. For this study, stable carbon, nitrogen, and sulfur isotope values from epidermis tissue were used to quantify isotopic overlap and compare isotopic niche size in loggerhead (Caretta caretta), green (Chelonia mydas), and Kemp's ridley (Lepidochelys kempii) turtles sampled from a shared foraging area located offshore of Crystal River, Florida, USA. Overall, the results revealed high degrees of isotopic overlap (>68%) among species, particularly between loggerhead and Kemp's ridley turtles (85 to 91%), which indicates there may be interspecific competition for resources. Samples from green turtles had the widest range of isotopic values, indicating they exhibit higher variability in diet and habitat type. Samples from loggerhead turtles had the most enriched mean δ34S, suggesting they may forage in slightly different micro-environments compared with the other species. Finally, samples from Kemp's ridley turtles exhibited the smallest niche size, which is indicative of a narrower use of resources. This is one of the first studies to investigate resource use in a multispecies foraging aggregation of marine turtles using three isotopic tracers. These findings provide a foundation for future research into the foraging ecology of sympatric marine turtle species and can be used to inform effective multispecies management efforts.

The first occurrence of Kemp’s Ridley turtle (Lepidochelys kempii) in Raja Ampat, Indonesia

Abstract. Widaysari F, Nugroho A, Arafat G, Sunoko R, Wahyudin RA, Sayuti M, Bakkula E, Ballamu F. 2023. The first occurrence of Kemp’s Ridley turtle (Lepidochelys kempii) in Raja Ampat, Indonesia. Biodiversitas 24: 4934-4942. Territory Indonesian waters are one of the waters in Southeast Asia that have been a turtle habitat; six of the seven types of turtles live in these waters, and Kemp ridley's turtle (Lepidochelys kempii) is the seventh reported to have recently emerged. The research objectives of the study were to identify the area location emergence of Kemp’s Ridley turtle, determine morphology, and release Kemp’s Ridley turtle. Location identification was based on the Raja Ampat District Central Statistics Agency data. Visual identification of turtles proceeds by looking at their morphology, namely carapace shape, number of vertebral and costal scutes, the form of the plastron, number of inframarginal scutes, and appearance of head shape juxtaposed on External Morphology. The water area where Kemp’s Ridley turtle was found had a constant temperature, moderate wind speed, high humidity, and rainfall. The results of identifying the turtle morphology matched Kemp’s Ridley turtle. After outreach to the community, Kemp’s Ridley turtles were released into nature. The first appearance of the Kemp’s Ridley turtle in Indonesia is undoubtedly an exciting study material for further study regarding the migration map, distribution, and other factors that cause changes in its migration.

Modeling juvenile sea turtle bycatch risk in commercial and recreational fisheries

Understanding the drivers of fisheries bycatch is essential for limiting its impacts on vulnerable species. Here we present a model to estimate the relative magnitude of sea turtle bycatch in major coastal fisheries across the southeastern USbased on spatiotemporal variation in fishing effort and the simulated distributionsof juvenile Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles recruiting from oceanic to nearshore habitats. Over the period modeled (1996-2017), bycatch in recreational fisheries was estimated to be greater than the sum of bycatch that occurred in commercial fisheries that have historically been considered high risks to turtles (e.g., those using trawls, gillnets, and bottom longlines). Prioritizing engagement with recreational anglers to reduce bycatch could be especially beneficial to sea turtle populations. Applying lessons learned from efforts to protect turtles in commercial fisheries may help meet the challenges that arise from the large, diffuse recreational fishing sector.

An Upper Miocene marine turtle from Panama that preserves osteocytes with potential DNA

ABSTRACT Lepidochelys is a genus of extant marine turtles that includes the critically endangered Kemp's Ridley turtle. The evolutionary history of this genus is poorly understood due to the lack of an undisputed fossil record for the group. Here we describe a partially preserved carapace from the Upper Miocene Chagres Formation of Panama, which represents the oldest fossil record of Lepidochelys. The specimen has rectangular, anteroposteriorly short pleural scutes, a characteristic shared with members of Lepidochelys. It is potentially closely related to L. olivacea because it shares a similar number of pleurals, but its precise taxonomic status remains uncertain. We discuss the ecological role that a marine turtle played in the paleoecosystem of the Chagres Formation. The new specimen exhibits exceptional preservation of bone sutures, sulci, sculpturing, and bone microstructure, including remains of blood vessels, collagen fibers, and osteocytes. This is the first time that a histochemical stain (DAPI) indicates preservation of a compound consistent with DNA in a fossil vertebrate outside Dinosauria. These data demonstrate the potential for DNA to persist in specimens that are both millions of years old and are from lower latitudes, which challenges traditional paradigms of biomolecular preservation.

Interspecific interactions among three species of sea turtle using a common resting area.

Interspecific interactions among three species of sea turtle using a common resting area.

Identification of a novel Neorickettsia species in a Kemp's ridley sea turtle with granulomatous nephritis and development of a quantitative PCR assay.

An adult male Kemp's ridley turtle was found dead on the coast of Kenedy County, Texas, in August 2019 with bilateral severe, diffuse granulomatous nephritis. Pan-bacterial 16S rRNA gene polymerase chain reaction (PCR) and amplicon sequencing of affected tissue indicated the presence of a Neorickettsia. Neorickettsia is a genus of obligate intracellular Alphaproteobacteria that are transmitted by digenean trematodes. For further characterization, primers were designed to amplify and sequence the groEL gene. Phylogenetic analysis found that the organism was distinct from other known species to a degree consistent with a novel species. Immunohistochemistry using an antibody directed against a Neorickettsia surface protein showed bacterial clusters within the renal granulomas. A species-specific quantitative PCR was designed and detected the organism within the liver and colon of the index case. A quantitative PCR survey of grossly normal kidneys opportunistically collected from additional stranded sea turtle kidneys detected this organism in five of 15 Kemp's ridley turtles, two of nine green turtles, and neither of two loggerhead turtles. Recognition of this novel organism in an endangered species is concerning; additional work is underway to further characterize the potential of this organism as a pathogen of sea turtles.

Historical Trends in New York State Cold-Stunned Sea Turtle Stranding-to-Release: 1998–2019

Long Island Sound and the Great Peconic Bay (New York) contain southern barrier lagoons and eastern bays and are known habitats for foraging juvenile populations of sea turtles during summer months. Every year, sea turtles strand throughout these areas due to climate-related cold snaps that typically occur in the late fall and lead to cold-stunning, a physiological temperature shock similar to hypothermia that renders turtles unable to swim and prone to wash up onto beaches. Cold-stunning events in this area tend to last longer than a few weeks and typically affect juvenile Kemp's ridley (Lepidochelys kempii), juvenile green (Chelonia mydas) and subadult loggerhead (Caretta caretta) sea turtles. The New York Marine Rescue Center, formally known as the Riverhead Foundation for Marine Research and Preservation, is the sole rehabilitation facility for cold-stunned sea turtles in New York and responds to the second-largest number of cold stuns in the Greater Atlantic Region, which encompasses marine ecosystems from Maine to North Carolina. Since 1998, a total of 510 sea turtles have been recovered from New York state waters or beaches between the months of October and February. Of these 510 cases, 5 individuals restranded under similar conditions following rehabilitation and release, resulting in 505 distinct sea turtles stranding due to cold-stunning. These 505 cold-stunned sea turtles were composed of 3 different species: 281 L. kempii (56.0%), 174 C. mydas (31.3%), 48 C. caretta (9.5%), and 2 hybrids (0.4%). Over the course of 22 yrs, stranding frequency varied from 3 to 85 turtles per season, with an average of 23. However, a large increase in stranding numbers began in 2007; average stranding numbers from 1998 to 2006 were 7 per season, increasing to 34 per season from 2007 to 2019. Multiple factors are likely contributing to the increase in stranding/rescue frequency such as the gradual warming of northern waters (which may entice turtles farther north and prevent their timely southern migration), development of a free public outreach program targeted at educating patrons about local sea turtle populations, and implementation of an effective beach patrolling system. More efficient management of patrolling efforts has contributed to the quick response time and resulting increase in live turtle rescues. In addition, modification and enhancement of in-house treatment protocols have contributed to the upward trend of successfully rehabilitated cold-stunned turtles. Understanding historical cold-stun trends will allow local and national organizations to identify needs and allocate funding for conservation initiatives of endangered Atlantic sea turtle populations.

Long-term insights into marine turtle sightings, strandings and captures around the UK and Ireland (1910–2018)

AbstractWith over a century of records, we present a detailed analysis of the spatial and temporal occurrence of marine turtle sightings and strandings in the UK and Ireland between 1910 and 2018. Records of hard-shell turtles, including loggerhead turtles (Caretta caretta, N = 240) and Kemp's ridley turtles (Lepidochelys kempii, N = 61), have significantly increased over time. However, in the most recent years there has been a notable decrease in records. The majority of records of hard-shell turtles were juveniles and occurred in the boreal winter months when the waters are coolest in the North-east Atlantic. They generally occurred on the western aspects of the UK and Ireland highlighting a pattern of decreasing records with increasing latitude, supporting previous suggestions that juvenile turtles arrive in these waters via the North Atlantic current systems. Similarly, the majority of the strandings and sightings of leatherback turtles (Dermochelys coriacea, N = 1683) occurred on the western aspects of the UK and the entirety of Ireland's coastline. In contrast to hard-shell turtles, leatherback turtles were most commonly recorded in the boreal summer months with the majority of strandings being adult sized, of which there has been a recent decrease in annual records. The cause of the recent annual decreases in turtle strandings and sightings across all three species is unclear; however, changes to overall population abundance, prey availability, anthropogenic threats and variable reporting effort could all contribute. Our results provide a valuable reference point to assess species range modification due to climate change, identify possible evidence of anthropogenic threats and to assess the future trajectory of marine turtle populations in the North Atlantic.

Venous blood gas and biochemical analysis of wild captured green turtles (Chelonia mydas) and Kemp's ridley turtles (Lepidochelys kempii) from the Gulf of Mexico.

Blood was collected from wild captured green and Kemp’s ridley turtles off the west coast of Florida, USA. Blood gases and biochemical values were analyzed using a point of care (POC) device in the field. Analytes include pH, partial pressure of carbon dioxide (pCO2), partial pressure of oxygen (pO2), total carbon dioxide (TCO2), bicarbonate (HCO3), base excess (BE), oxygen saturation (sO2), lactate, sodium (Na), potassium (K), chloride (Cl), total carbon dioxide (TCO2), anion gap, ionized calcium, glucose, blood urea nitrogen (BUN), creatinine (Crea), hematocrit (Hct), and hemoglobin (Hb). These are novel data for wild healthy Kemp’s ridley turtles, and results for green turtles were generally consistent with past studies of green turtles with exceptions primarily in blood gas values. Ninety percent of the green turtles had fibropapillomatosis (FP), but none of the blood analytes were correlated with disease severity. Only BUN was correlated with weight of green turtles, and there was no correlation between blood parameters and weight of Kemp’s ridley turtles. This study provides data that are useful in understanding the physiologic status of sea turtles specific to this region, allowing for comparisons to other populations, life stages, and disease states.

Preserved collagen reveals species identity in archaeological marine turtle bones from Caribbean and Florida sites.

Advancements in molecular science are continually improving our knowledge of marine turtle biology and evolution. However, there are still considerable gaps in our understanding, such as past marine turtle distributions, which can benefit from advanced zooarchaeological analyses. Here, we apply collagen fingerprinting to 130 archaeological marine turtle bone samples up to approximately 2500 years old from the Caribbean and Florida's Gulf Coast for faunal identification, finding the vast majority of samples (88%) to contain preserved collagen despite deposition in the tropics. All samples can be identified to species-level with the exception of the Kemp's ridley (Lepidochelys kempii) and olive ridley (L. olivacea) turtles, which can be separated to genus level, having diverged from one another only approximately 5 Ma. Additionally, we identify a single homologous peptide that allows the separation of archaeological green turtle samples, Chelonia spp., into two distinct groups, which potentially signifies a difference in genetic stock. The majority of the archaeological samples are identified as green turtle (Chelonia spp.; 63%), with hawksbill (Eretmochelys imbricata; 17%) and ridley turtles (Lepidochelys spp.; 3%) making up smaller proportions of the assemblage. There were no molecular identifications of the loggerhead turtle (Caretta caretta) in the assemblage despite 9% of the samples being morphologically identified as such, highlighting the difficulties in relying on morphological identifications alone in archaeological remains. Finally, we present the first marine turtle molecular phylogeny using collagen (I) amino acid sequences and find our analyses match recent phylogenies based on nuclear and mitochondrial DNA. Our results highlight the advantage of using collagen fingerprinting to supplement morphological analyses of turtle bones and support the usefulness of this technique for assessing their past distributions across the Caribbean and Florida's Gulf Coast, especially in these tropical environments where DNA preservation may be poor.

Warming seas increase cold-stunning events for Kemp’s ridley sea turtles in the northwest Atlantic

Since the 1970s, the magnitude of turtle cold-stun strandings have increased dramatically within the northwestern Atlantic. Here, we examine oceanic, atmospheric, and biological factors that may affect the increasing trend of cold-stunned Kemp’s ridleys in Cape Cod Bay, Massachusetts, United States of America. Using machine learning and Bayesian inference modeling techniques, we demonstrate higher cold-stunning years occur when the Gulf of Maine has warmer sea surface temperatures in late October through early November. Surprisingly, hatchling numbers in Mexico, a proxy for population abundance, was not identified as an important factor. Further, using our Bayesian count model and forecasted sea surface temperature projections, we predict more than 2,300 Kemp’s ridley turtles may cold-stun annually by 2031 as sea surface temperatures continue to increase within the Gulf of Maine. We suggest warmer sea surface temperatures may have modified the northerly distribution of Kemp’s ridleys and act as an ecological bridge between the Gulf Stream and nearshore waters. While cold-stunning may currently account for a minor proportion of juvenile mortality, we recommend continuing efforts to rehabilitate cold-stunned individuals to maintain population resiliency for this critically endangered species in the face of a changing climate and continuing anthropogenic threats.

Ameliorating transport-related stress in endangered Kemp's ridley sea turtles (Lepidochelys kempii) with a recovery period in saltwater pools.

Sea turtle rehabilitation clinics and aquaria frequently transport stranded sea turtles long distances out of water, e.g. for release at sites with appropriate water temperatures. Endangered Kemp's ridley turtles (Lepidochelys kempii) are known to exhibit an adrenal stress response during such transports. In an opportunistic study of turtles transported by road from Massachusetts to Georgia for release, we tested whether placing turtles in saltwater pools for short periods after transport would help turtles recover from transport-related stress. Eighteen juvenile Kemp's ridley turtles were examined and blood samples collected (1) immediately pre-transport, (2) immediately post-transport and (3) after a 6 h (n = 9) or 24 h (n = 9) post-transport period in unfamiliar pools, after which all turtles were released to the sea. Blood samples were analyzed for corticosterone, glucose, total white blood cell (WBC) count, heterophil/lymphocyte (H/L) ratio, pH, pO2, pCO2, HCO3 (bicarbonate), sodium, potassium, ionized calcium, lactate and hematocrit. Though the majority of turtles remained in good clinical condition, corticosterone, glucose, WBC and H/L elevated significantly during transport, while potassium declined slightly but significantly. After at least 6 h in a saltwater pool, potassium and glucose returned to pre-transport baselines and corticosterone partially recovered toward baseline. Extending the pool time to 24 h did not markedly enhance the physiological recovery of turtles, and two immune measures (WBC, H/L) remained elevated from the effect of transport. Six hours in a saltwater pool appears to facilitate the recovery of Kemp's ridley sea turtles from transport-related stress and may therefore improve their readiness for release.

Monoclonal antibodies against loggerhead sea turtle, Caretta caretta, IgY isoforms reveal differential contributions to antibody titers and relatedness among other sea turtles

Serum from loggerhead sea turtles, Caretta caretta, was collected from the southeast Atlantic Ocean during routine summer monitoring studies in 2017. Serum immunoglobulin IgY was purified and used to develop IgY isoform-specific monoclonal antibodies (mAb). mAb LH12 was developed against the 66 kDa heavy chain of IgY, mAb LH1 was developed against the truncated heavy chain of approximately 37 kDA, and mAb LH9 was developed against the 23 kDa light chains. mAb LH9 reacts with the light chains of all sea turtles, mAb LH12 reacts with the long heavy chain of all sea turtles within the family Cheloniidae, and mAb LH1 reacts with the truncated form of IgY in both olive and Kemp's ridley turtles. Circulating IgY antibodies against three different marine bacterial pathogens were determined in 16 loggerhead samples using these mAbs. mAb LH12 detects higher titers than mAb LH1, and mAb LH9 detects the highest titers.

The Effect of Delayed Hospitalization in Cold-Stunned Kemp's Ridley Turtles (Lepidochelys kempii)

Abstract Kemp's ridley turtles (Lepidochelys kempii) are a critically endangered marine species found along the eastern coast of the United States and Mexico. During autumn and early winter, turtles in the northern end of this range may become cold-stunned and stranded if they fail to migrate to warmer waters. Depending on the time of day that stranded turtles are discovered, turtles may be kept overnight by stranding officials before being hospitalized. Turtles for which hospitalization was delayed overnight had higher respiratory rates, packed cell volumes, plasma total solids, and blood potassium concentrations in comparison to turtles that were hospitalized on the day of stranding. There was no significant difference in outcome for turtles presented immediately versus those affected by delayed presentation. These findings suggest that cold-stunned turtles affected by an overnight hospitalization delay may benefit from basic medical treatments, such as fluid therapy, until they can be transferred to a ...

Potential effects of brevetoxins and toxic elements on various health variables in Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles after a red tide bloom event

Natural biotoxins and anthropogenic toxicants pose a significant risk to sea turtle health. Documented effects of contaminants include potential disease progression and adverse impacts on development, immune function, and survival in these imperiled species. The shallow seagrass habitats of Florida's northwest coast (Big Bend) serve as an important developmental habitat for Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles; however, few studies have been conducted in this area. Our objectives were (1) to evaluate plasma analytes (mass, minimum straight carapace length, body condition index [BCI], fibropapilloma tumor score, lysozyme, superoxide dismutase, reactive oxygen/nitrogen species, plasma protein electrophoresis, cholesterol, and total solids) in Kemp's ridleys and green turtles and their correlation to brevetoxins that were released from a red tide bloom event from July–October 2014 in the Gulf of Mexico near Florida's Big Bend, and (2) to analyze red blood cells in Kemp's ridleys and green turtles for toxic elements (arsenic, cadmium, lead, mercury, selenium, thallium) with correlation to the measured plasma analytes. Positive correlations were observed between brevetoxins and α2-globulins in Kemp's ridleys and α2- and γ-globulins in green turtles, indicating potential immunostimulation. Arsenic, cadmium, and lead positively correlated with superoxide dismutase in Kemp's ridleys, suggesting oxidative stress. Lead and mercury in green turtles negatively correlated with BCI, while mercury positively correlated with total tumor score of green turtles afflicted with fibropapillomatosis, suggesting a possible association with mercury and increased tumor growth. The total tumor score of green turtles positively correlated with total protein, total globulins, α2-globulins, and γ-globulins, further suggesting inflammation and immunomodulation as a result of fibropapillomatosis. Lastly, brevetoxin concentrations were positively related to tumor score, indicating potential tumor promotion by brevetoxin. These results signify that brevetoxins and toxic elements elicit various negative effects on sea turtle health, including immune function, oxidative stress, and possibly disease progression.

Use of Positive Pressure Ventilation in Cold-Stunned Sea Turtles: 29 Cases (2008–2014)

Abstract Between 2008 and 2014, mechanical positive pressure ventilation (PPV) was used to manage 48 critically ill, cold-stunned sea turtles during their first week of treatment. Twenty-nine turtles had complete records for analysis and no ventilator complications, including 21 Kemp's ridley turtles (Lepidochelys kempii), four loggerhead turtles (Caretta caretta), and four green turtles (Chelonia mydas). Indications for PPV included poor responsiveness, bradypnea or apnea, bradycardia, and respiratory acidosis. Twenty (68.9%) turtles were successfully extubated, seven (24.1%) turtles died naturally during PPV, and two (7.0%) turtles were euthanized during PPV. Of the 20 turtles that were extubated, 11 (55%) survived over 24 h after extubation and were considered successfully weaned from the ventilator, but only four (20%) turtles survived to eventual release. Throughout PPV, improvements in respiratory, cardiovascular, and clinicopathologic status were variable, likely related to the degree of illness at...

Brevetoxin exposure in sea turtles in south Texas (USA) during Karenia brevis red tide.

Five green (Chelonia mydas) and 11 Kemp's ridley (Lepidochelys kempii) sea turtles found dead, or that died soon after stranding, on the southern Texas (USA) coast during 2 Karenia brevis blooms (October 2015, September-October 2016) were tested for exposure to brevetoxins (PbTx). Tissues (liver, kidney) and digesta (stomach and intestinal contents) were analyzed by ELISA. Three green turtles found alive during the 2015 event and 2 Kemp's ridley turtles found alive during the 2016 event exhibited signs of PbTx exposure, including lethargy and/or convulsions of the head and neck. PbTx were detected in 1 or more tissues or digesta in all 16 stranded turtles. Detected PbTx concentrations ranged from 2 to >2000 ng g-1. Necropsy examination and results of PbTx analysis indicated that 10 of the Kemp's ridleys and 2 of the green turtles died from brevetoxicosis via ingestion. This is the first documentation of sea turtle mortality in Texas attributed to brevetoxicosis.

Glomerular Filtration Rates of Naturally Cold-Stunned Kemp's Ridley Turtles (Lepidochelys kempii): Comparison of Initial vs. Convalescent Values

Abstract Iohexol clearance testing was used to determine glomerular filtration rates (GFR) for 12 juvenile Kemp's ridley turtles (Lepidochelys kempii) that stranded because of cold-stunning. Iohexol was injected intravenously at 75 mg/kg, with subsequent plasma collection at 4, 8, and 24 h post-injection for measurement of iohexol iodine concentrations by inductively coupled plasma mass spectrometry (ICP-MS). Initial GFR was determined on median day 4 of hospitalization (range day 2–5) at an average body temperature of 19°C (66°F) (range 18–21°C [64–70°F]). Mean initial GFR was 4.6 mL/kg/h (range 1.9–8.7 mL/kg/h, n = 10). Convalescent GFR was determined on median day 126 of hospitalization (range day 108–232) at an average body temperature of 24°C (75°F) (range 23–25°C [74–77°F]). Mean convalescent GFR was 13.5 mL/kg/h (range 8.5–21.5 mL/kg/h, n = 10). Statistical analysis of paired initial and convalescent data demonstrated a significantly lower initial GFR, body weight, straight carapace length, and bod...