Kinosternon Research Articles

Effect of three feeding management systems on some reproductive parameters of Scorpion mud turtles (Kinosternon scorpioides) in Brazil

Chelonians have been exploited since ancient times for their meat, eggs, fat, and offal, among other things. Among these animals, there is Scorpion mud turtle (Kinosternon scorpioides) which is an omnivorous turtle with semiaquatic habits and is widely consumed in Brazil. The aim of this study was to evaluate the influence of different feeding management systems on the reproductive performance of captive-bred Scorpion mud turtles, including egg quality and chemical composition. Study animals included 15 males and 48 females, divided into three groups. Animals were fed with either a commercial diet or a commercial diet supplemented with one of two different mixes (wet diet). All animals were fed at 1% BW/day divided on Mondays, Wednesdays, and Fridays. Treatments were as follows: TR = 100% fish food (22% CP); TRM1 = 70% fish food + 30% mix 1 (bovine offal and fish); TRM2 = 70% fish food + 30% mix 2 (bovine offal, fish, and shrimp). Samples were collected during 7months, and eggs were identified, weighed, measured, and frozen for later analysis. Statistical analyses, including ANOVA, were performed using the program SAEG 9.0. Measurements taken from the nests were compared using the Tukey's test (P < 0.05). The different diets were associated with differential egg-laying performance and eggshell thickness. Animals fed with wet diets containing protein of animal origin displayed the best performance. Furthermore, nests with fewer eggs contained eggs of better external quality (e.g., greater length, width, and eggshell thickness). Finally, animals fed with only commercial feed produced eggs with lower saturated fatty acid content.

Morphological aspects of the ovaries of turtle Kinosternon scorpioides raised in captivity

The swear turtle "jurará" (Kinosternon scorpioides) is a mud turtle of the Amazon region exposed to disordering capture in the rural areas of Maranhão, Brazil. Despite its popularity in these areas, little meaningful information regarding the reproductive morphology is currently available, fact that impedes the adoption of policies for preservation of the species. To obtain more information, we studied the ovarian morphology adult jurará females kept in captivity by morphological and morphometric analysis in the dry and rainy season. The results revealed that all females were sexually mature and were in a vitellogenic period. The ovaries are two irregular structures composed by follicles in different stages of development (primary, secondary and tertiary) scattered in a stroma of loose connective highly vascularized tissue. The ovary weight was 6.25±4.23g and 2.27±1.42g, for the right and left one respectively. The gonadosomatic indexes were 2.06% for the dry season and 1.79% for the rainy season. The average of the follicles was 29.83 units per ovary. Microscopically, the mature ovaries revealed a basal layer composed by four cellular layers: the inner and outer theca, stratum granulosum with perivitelline membrane and zona radiata with vitelline membrane. No significant differences were observed in the ovaries either in the dry or wet period.

Coexistence of Placobdella costata (Fr. Müller, 1846) (Hirudinida: Glossiphoniidae) and mud turtle Emys orbicularis

Emys orbicularis is receding from Europe, mainly due to anthropogenic habitat changes. Its parasite, Placobdella costata, is widely distributed within both the former and the present distribution range of the host. Though closely associated with the mud turtle, it may have other hosts (birds, amphibians, reptiles). Its reproductive period coincides with that of its host’s migration to the breeding grounds, thus facilitating dispersal of the parasite. Based on literature data we have analyzed the geographic spread of P. costata and mud turtle to observe the possible overlap of their habitats. Observations on the population of mud turtle and the associated leech species (P. costata) were carried out in eastern Poland — Podlasie Lowland. The studies were conducted in spring and summer in 1986–1993. The leeches were collected from the turtles caught in the water and on land. Observations showed that most leeches were found on turtles inhabiting the lake or moving to a breeding area. The greatest intensity of invasion was observed in June and July and that most leeches were observed in female E. orbicularis characterized by greater length of the carapace and weight, compared with males and juvenile individuals.

A fossil mud turtle (Testudines, Kinosternidae) from the early middle Miocene (early Barstovian) of New Mexico

ABSTRACT The nearly complete skeleton of a mud turtle, Kinosternon skullridgescens, n. sp., is described from Santa Fe County, New Mexico. The specimen was collected from the early middle Miocene, early Barstovian, Skull Ridge Member of the Tesuque Formation (16.0–14.9 Ma) and is one of the oldest and most complete fossil representatives of the genus Kinosternon. Phylogenetically, the new taxon is placed on the stem of the flavescens group in conjunction with the extinct Kinosternon pojoaque from the late Barstovian of New Mexico. In addition to the flavescens group, K. skullridgescens shares morphological similarities with members of the subrubrum group (of North America), as well as with Kinosternon herrerai (from gulf drainages of eastern Mexico). Close proximity of the fossils K. skullridgescens and K. pojoaque to Mexico suggests that a small-plastroned ancestor of the extant taxa K. herrerai, Kinosternon angustipons (from lower Central America), and Kinosternon dunni (from northwestern South America) could have dispersed from North America into Central America by the middle Miocene (Barstovian). Phylogenetic results based on morphology suggest that the taxon Kinosternon steindachneri (formerly Kinosternon subrubrum steindachneri) be reinstated at the species level.

Long Distance Aquatic Movement and Home-Range Size of an Eastern Mud Turtle, Kinosternon subrubrum, Population in the Mid-Atlantic Region of the United States

Abstract The aquatic movement patterns and home-range size of the Eastern Mud Turtle, Kinosternon subrubrum, have received little attention. We radio-tracked 5 adult females and 5 adult males during 2 yrs in the Mid-Atlantic region of the United States. Our mean estimates of home-range size (18.6 ± 23 ha in 2008 and 16.3 ± 16.3 ha in 2009) and maximum aquatic distance traveled (815 ± 455 m in 2008 and 774 ± 331 m in 2009) suggest that K. subrubrum is highly adept at movement in aquatic environments.

An extinct mud turtle of the Kinosternon flavescens group (Testudines, Kinosternidae) from the middle Miocene (late Barstovian) of New Mexico

ABSTRACT The complete skeleton of a fossil mud turtle, Kinosternon pojoaque, n. sp., is described from the late Barstovian Rodent Pocket, San Ildefonso Locality of Santa Fe County, New Mexico. The new species represents the oldest member of the Kinosternon flavescens group and suggests that this clade first evolved in the southwestern United States, which, along with northern Mexico, is the center of diversity for these turtles today. The new taxon exhibits plastral characters that suggest phylogenetic affinities with Kinosternon angustipons, Kinosternon dunni, Kinosternon herrerai, Kinosternon hirtipes, and Kinosternon sonoriense and is interpreted here as an example of a morphological intermediate between the clade composed of these taxa and the flavescens group. The new fossil, along with other Miocene Kinosternon fossils from New Mexico, provides evidence that the flavescens clade likely diverged from other southwestern, Central, and South American Kinosternon by at least the late Barstovian, 14.3–13.3 million years ago.

Optimal egg size in a suboptimal environment: reproductive ecology of female Sonora mud turtles (Kinosternon sonoriense) in central Arizona, USA

We studied the reproductive ecology of female Sonora mud turtles (Kinosternon sonoriense) at Montezuma Well, a chemically-challenging natural wetland in central Arizona, USA. Females matured between 115.5 and 125 mm carapace length (CL) and 36-54% produced eggs each year. Eggs were detected in X-radiographs from 23 April-28 September (2007-2008) and the highest proportion (56%) of adult females with eggs occurred in June and July. Clutch frequency was rarely more than once per year. Clutch size was weakly correlated with body size, ranged from 1-8 (mean = 4.96) and did not differ significantly between years. X-ray egg width ranged from 17.8-21.7 mm (mean 19.4 mm) and varied more among clutches than within. Mean X-ray egg width of a clutch did not vary significantly with CL of females, although X-ray pelvic aperture width increased with CL. We observed no evidence of a morphological constraint on egg width. In addition, greater variation in clutch size, relative to egg width, suggests that egg size is optimized in this hydrologically stable but chemically-challenging habitat. We suggest that the diversity of architectures exhibited by the turtle pelvis, and their associated lack of correspondence to taxonomic or behavioral groupings, explains some of the variation observed in egg size of turtles.

Evidence for the Morphological Constraint Hypothesis and Optimal Offspring Size Theory in the Mexican Mud Turtle (Kinosternon integrum)

Optimal offspring size theory states that natural selection should balance reproductive output by optimizing between offspring size and offspring number. If a species has evolved an optimal offspring size, the fitness of larger females should be increased by simply producing more offspring of an optimum size. In contrast, when offspring size is not optimized, the morphological constraint hypothesis may apply, and in this case, maternal fitness is increased by producing the greatest number of the largest offspring that mothers are physically capable of producing. We used a log-log allometric regression approach on clutch size, egg size, and body size data to test the application of optimal offspring size theory and the morphological constraint hypothesis in the Mexican mud turtle (Kinosternon integrum) in southern Mexico. Our results indicate that this turtle seems to follow the morphological constraint hypothesis when all data are analyzed together, but when data are divided between small (< 140 mm plastron length) and large females (> 140 mm plastron length), optimal offspring (egg) size theory was supported only in large females, while the morphological constraint hypothesis was supported in small females. Our results thus indicate that K. integrum females may increase their fitness in two different, size-dependent ways as they grow from size at sexual maturity to maximum body size.

Response of a Yellow Mud Turtle (Kinosternon flavescensAgassiz) Community to Habitat Change: Management Implications for a Nature Preserve

Yellow mud turtles (Kinosternon flavescens) have been studied in and around a nature preserve near Muscatine, Iowa, for over three decades. The deep sand prairie habitat, unusual for Iowa, has incurred a variety of human disturbances since the 19th century. The area has been managed for natural habitat for the last 40 years, initially by private hunt club (1970s) and now as a private conservation area (late 1970s to the present). The surrounding landscape either continues to suffer a variety of anthropogenic disturbances or was abandoned following disturbances during the 20th century. Recent survey data for yellow mud turtles, an Iowa endangered species, were compared with past surveys to determine efficacy of management practices and effects of habitat alteration on the species. Because yellow mud turtles require wetlands in spring for hydration, feeding, and mating, we specifically focused on impacts and management of former oxbow habitats once connected to the Mississippi River. We conclude that wetlands outside the preserve no longer contain populations of yellow mud turtles. Causes of decline include a history of severe environmental disturbance, in addition to perpetual populations of permanent water-adapted aquatic turtles (e.g., Chrysemys picta) and predatory fishes that either compete for food with yellow mud turtles or prey upon juveniles. Our studies validate the necessity of wetlands that are shallow enough for aquatic turtle and fish winterkills. However, the wetlands also require sufficient depth each spring to satisfy the hydration and feeding requirements for yellow mud turtles.

Reassessment of a Putative Fossil Stinkpot (Kinosternidae: Sternotherus) from the Late Miocene (Clarendonian) of Kansas

The oldest paleontological record of the Stinkpot Musk Turtle, Sternotherus odoratus, from the WaKeeney local fauna (approximately 10 million years ago, Mya) is refuted here. Kinosternids from this fauna are represented only by the genus Kinosternon. Kinosternon sp. probably represents a new taxon, but lack of sufficient material hinders a proper description. A gap of between 9 and 12.5 million years now exists between the first occurrences of Sternotherus (at approximately 4.5–7 Mya) and sister group Kinosternon (between 16 and 17 Mya).

Nematode Parasites of Five Species of Turtles from the Area de Conservación Guanacaste, Costa Rica, with Description of a New Species of Falcaustra

Abstract Twenty-three turtles representing 3 families (5 species)—Chelydridae: common snapping turtle, Chelydra serpentina; Emydidae: brown wood turtle, Rhinoclemmys annulata; painted wood turtle, Rhinoclemmys pulcherrima; Kinosternidae: white-lipped mud turtle, Kinosternon leucostomum; scorpion mud turtle, Kinosternon scorpioides—collected in the Area de Conservacion Guanacaste, Costa Rica, were subjected to postmortem examination. Gravid nematodes representing 10 species, 9 previously described—Atractis costaricaensis, Cosmocercoides variabilis, Dracunculus globocephalus, Falcaustra chelydrae, Falcaustra tikasinghi, Klossinemella caballeroi, Sauricola sauricola, Serpinema magathi, Spiroxys figueiredoi—were found. Eight new host records and 7 new locality records are reported. A new species of Falcaustra inhabiting Rhinoclemmys annulata is described; it is the only known member of the genus lacking a pseudosucker, but having a toothed chamber separating the vestibule and the pharynx. Only Falcaustra kins...

Terrestrial Flight Response: A New Context for Terrestrial Activity in Sonoran Mud Turtles

The risk allocation hypothesis predicts that animals should be most averse to risk during brief and infrequent high risk situations. For animals in shallow aquatic habitats, encounters with terrestrial predators may represent such a situation. Terrestrial flight responses, acute movements from water onto land following a disturbance, may be a viable escape strategy during encounters with terrestrial predators foraging in shallow aquatic habitats. Sonoran mud turtles (Kinosternon sonoriense) occur in intermittent aquatic habitats in the Peloncillo Mountains, New Mexico. When Sonoran mud turtles were captured by hand in shallow pools or shallow stock tanks they frequently underwent terrestrial flight responses. In five of six trials in shallow stock tanks, and three of seven trials in shallow pools, turtles left the water within 20 min of being released, often climbing out of sight up relatively steep slopes. This behavior was not observed in four trials in which turtles were captured with hoop nets in deep stock tanks. Turtles that underwent terrestrial flight responses were significantly larger than non-responders. Terrestrial flight responses appear to be a risk aversion strategy in Sonoran mud turtles occupying shallow aquatic habitats. This unusual behavior may be widespread among animals that inhabit shallow aquatic habitats.

Strategy and scenario for wetland conservation in India

Wetlands are the most important ecosystems for the organisms in Animal Kingdom (including human beings) and Plant Kingdom. There are about hundred species of flora in and around Indian Wetlands. They include Sagittaria montividensis, Cryptocoryne ciliata, Cyperus spp., Acrostichum aureum, Ipomoea aquatica, etc. They are also the habitats of several mammals like the marsh mongoose, small Indian mongoose, palm civet and the small Indian civet. Endangered species like the Indian mud turtle have also been found in the wetlands. Certain species of birds also visit the wetlands. Prominent ones are grebe, coot, darter, shag, cormorant, teals, egrets, jacanas, snipes, tern, eagle, sand piper, gulls, rails and kingfishers. The wetlands are important for production of foods and human safety. The East Kolkata wetlands with their garbage farms and fishponds have provided the city with three facilities, i.e., food, sanitation and livelihood. They also provide ecological security to the city of Kolkata. Over the past few years, wetlands have come under severe threat. With the population explosion, some of the largest fish farms have been converted from pisiculture to paddy cultivation. Industries also empty their wastewater effluent without treatment to the channels flowing eastward and these ultimately land up in the wetlands. This has caused substantial amount of deposits of metal in the canal sludge and made the wastewater incapable for the consumption by the fishes and the plants grown in the wetland. Nevertheless, due to urbanization or human interference, the wetland and its unique ecosystem biodiversity are in danger. After Ramsar Convention, 1971, different acts have been passed in India for conservation of wetlands, along with conducting general awareness program for the local people by the government, conducting different programs, management of wetlands, and research by the government, NGOs and other institutions.

Reproduction in the Red-Cheeked Mud Turtle (Kinosternon scorpioides cruentatum) in Southeastern Mexico and Belize, with Comparisons Across the Species Range

Abstract Reproduction in the red-cheeked mud turtle (Kinosternon scorpioides cruentatum) was studied in southeastern Mexico and Belize (Yucatan Peninsula) on the basis of museum and field-collected specimens. Adult females (mean carapace length [CL] = 110 mm) were not significantly larger than adult males (mean CL = 108 mm). Females matured at 100–105 mm CL and an estimated age of 9–10 years. Annual reproduction by females was apparently continuous for at least 10 months of the year (August–June), with the production of multiple annual clutches (possibly as many as 5) being typical and the number of clutches per year increasing with female size. Eggs exhibit diapause and embryonic estivation and apparently hatch in nature during the wet season (June–August) after up to 9 months in the nest. Modal clutch size was only 2 eggs (mean 2.2; range 1–4), and clutch size increased with female body size. Egg size averaged 31.5 × 16.6 mm and 5.5 g and did not vary with female body size. Relative egg mass (REM =...

Demography, Terrestrial Behavior, and Growth of Sonora Mud Turtles (Kinosternon sonoriense) in an Extreme Habitat

We studied the population biology of Sonora mud turtles (Kinosternon sonoriense) for 10 yr in an extremely hot and dry desert stream habitat in central Arizona. Adults made up 34.4% of the population. Modeling with Program MARK indicated that both age class (adult vs. juvenile-hatchling) and season contributed significantly to the probability of capture. The presence of exotic crayfish (Orconectes virilis) and age class were significant contributors to turtle survival, supporting the hypothesis that exotic crayfish are important predators on hatchlings. Population density estimates indicated low density over the range of water availability. Both adults and juveniles made long-distance movements along the dry stream bed between pools of water. Males and females were both likely to make long-distance movements and were sometimes absent from the study site for years at a time. In addition to terrestrial estivation in foresummer drought, turtles apparently hibernated on land in winter when standing water was available. Growth fit a von Bertalanffy model very well. We make the first report of growth rates for hatchling K. sonoriense. Growth rates estimated from shell annuli were consistent with similar estimates for older turtles in other studies. Measured growth rates, however, were much higher than annuli-based estimates. In contrast to other populations, we determined that hatchlings and juveniles in our study added 1–3 plastron annuli each year, making age estimation from annuli difficult. Understanding relationships between habitat use, invasive predators, and demographics is essential for effective management of low-density populations.

Distribution, habitat characteristics, and diet of freshwater turtles in the surrounding area of the Seomjin River and Nam River in southern Korea

In this study, we evaluated the distribution, habitat characteristics, and diet of two Korean freshwater turtle species (Chinemys reevesii, Pelodiscus sinensis) and an invasive turtle species (Trachemys scripta elegans) in the area surrounding the Seomjin River and the Nam River. We surveyed basking turtles in multiple locations along a 48-km stretch of the Seomjin River and in 99 reservoirs distributed along the Seomjin and Nam rivers from June to September, 2009. We observed 8 and 6 red-eared turtles in 3 reservoirs and at 3 sites in the Seomjin River, respectively, and 33 Reeve's turtles in 9 reservoirs. There were also 28 and 16 mud turtles detected at 15 sites along the Seomjin River and in 8 reservoirs, respectively. Among the 14 biotic and abiotic habitat characteristics that might influence the abundance of freshwater turtles in reservoirs, only the distance between a reservoir and the nearest residential areas was correlated negatively with abundance. With regard to the diet, all Reeve's and red-eared turtles investigated were determined to forage on water snails. Some turtles also foraged on vegetation and aquatic invertebrates. Additionally, we found fish in the stomach of one of the Reeve's turtles, and dragonflies in the stomachs of two red-eared turtles.

Survival and recruitment of semi-aquatic turtles in an urbanized region

Turtles are long-lived organisms that require high survivorship to maintain stable populations. Additionally, turtles are thought to be particularly susceptible to negative effects associated with anthropogenic habitat modification such as increased presence of human-subsidized predators and increased road mortality. Recruitment may also be reduced in populations surrounded by developed landscapes because of high road densities which limits connectivity among habitats or because of limited nesting sites. To address the impacts of habitat development on turtle vital rates, we studied three species of semi-aquatic turtles, yellowbelly sliders (Trachemys scripta), eastern mud turtles (Kinosternon subrubrum), and common snapping turtles (Chelydra serpentina), in the urbanized Charlotte-metropolitan area of North Carolina. Mark-recapture data were analyzed in Program MARK using AIC model selection methods to evaluate models analyzing the effects of pond, sex, and time on both survivorship and recruitment rates. Our results yielded high survivorship estimates for sliders and snapping turtles (73–92.5% and 91.4–99.4%, respectively), indicating that these species were likely not severely affected by habitat modification. In contrast, mud turtles exhibited lower survivorship estimates (56.8–73.6%) than have been previously documented for this species, an observation we attribute to their reliance on terrestrial habitats where they may encounter greater densities of mesopredators in developed areas. Recruitment estimates indicated that most populations were subsidized by sizable additions each year, with the notable exception of snapping turtles whose movement may be limited by increased road densities. Our results suggest that anthropogenic habitat modification has species-specific effects and could imperil certain populations in urbanized areas.

Testing avian, squamate, and mammalian nuclear markers for cross amplification in turtles

We used PCR amplifications to assess 120 previously described nuclear markers for phylogeographic and phylogenetic analysis in turtles. Twenty-seven of 120 markers amplified a single PCR product for both the western pond turtle (Emys marmorata) and the West African mud turtle (Pelusios castaneus), 71 amplified a single product in either E. marmorata or P. castaneus, and a subset of eight markers amplified single products across a test panel of 11 additional turtle species representing a broad sample of turtle diversity. Our ongoing research shows that nuclear markers developed for birds, squamates, and other vertebrate taxa can be useful for analyses of turtles, suggesting that many primers are transferable across large phylogenetic distances.

Reptilian Prey of the Sonora Mud Turtle (Kinosternon sonoriense) with Comments on Saurophagy and Ophiophagy in North American Turtles

We detected evidence of predation by the Sonora mud turtle (Kinosternon sonoriense) on the Arizona alligator lizard (Elgaria kingii nobilis) and the ground snake (Sonora semiannulata) at Montezuma Well, Yavapai County, Arizona. Lizards have not been reported in the diet of K. sonoriense, and saurophagy is rare in turtles of the United States, having been reported previously in only two other species:, the false map turtle (Graptemys pseudogeographica) and the eastern box turtle (Terrapene carolina). While the diet of K. sonoriense includes snakes, ours is the first record of S. semiannulata as food of this turtle. Ophiophagy also is rare in turtles of the United States with records for only five other species of turtles. Given the opportunistic diets of many North American turtles, including K. sonoriense, the scarcity of published records of saurophagy and ophiophagy likely represents a shortage of observations, not rarity of occurrence.

The Wolf’s Ear

The Wolf’s Ear