John L Carr | University of Louisiana at Monroe (original) (raw)

Papers by John L Carr

Chelonian Research Monographs, Oct 21, 2023

RESUMEN Pocos estudios demográficos de larga duración han sido realizados en tortugas dulceacuíco... more RESUMEN Pocos estudios demográficos de larga duración han sido realizados en tortugas dulceacuícolas de Suramérica, pese a la necesidad de este tipo de investigación para esclarecer las variaciones naturales y fortalecer procesos de conservación en este grupo particular. En esta investigación se estudió la variación en la demografía de una población de la tortuga de río chocoana (Rhinoclemmys nasuta), a partir de información registrada en una localidad insular del Pacífico colombiano entre 2005 y 2012. En esta localidad se capturaron manualmente tortugas en cinco riachuelos con un área total de 0,4 ha. Se calculó el tamaño poblacional con el método Jolly-Seber en cuatro periodos (2005-06, 2007, 2011 y 2012), y se comparó la estructura poblacional. Se estimó la probabilidad de supervivencia y la probabilidad de captura para machos, hembras y juveniles utilizando el modelo Cormack-Jolly-Seber, y la tasa de crecimiento poblacional con el modelo POPAN. Se evidenciaron aumentos y disminuciones en el tamaño de la población. Se evidenció un aumento significativo del porcentaje de juveniles que hacen parte de la población durante el periodo de estudio. En todos los periodos las hembras dominaron la estructura de sexos de la población. Las variaciones temporales en el tamaño poblacional pueden deberse a cambios naturales en el hábitat o a efectos denso-dependientes. Sin embargo, también pueden corresponder a fluctuaciones normales en los parámetros poblacionales, por lo tanto monitoreos continuos donde se puedan correlacionar factores ambientales y físicos del hábitat podrían permitirnos elucidar a que se deben estas variaciones. Palabras clave: estructura poblacional, probabilidad de supervivencia, tamaño poblacional, tasa de crecimiento poblacional.

Se presenta una clavepara/as cinco espf:ciesde tortugas terrestres y de agua dulce encontradas en... more Se presenta una clavepara/as cinco espf:ciesde tortugas terrestres y de agua dulce encontradas en el Ecuador Occidental. La información df: cada especie incluye referencias de los especímenes examinados y de los registros de la literatura, así como una discusión detallada de ciertas localidades erróneas o problemáticas. Además, se adjunta un índice toponímico de todos los lugares mencionados en el texto.-ABSTRACT A kf:Y for the five species of terrestrial and freshwater turtles found in western E;cuador is presented. An account for each species includes reference to specimens examined and literature records, as well as a detailed discussÍ(m of certain erroneous or problematic localities. A completely cross referenced gazetteer is included for all place names mentioned in the texto IN T R O DUCe ION encuentran en tres de estas áreas. Las tortugas de las Galápagos han sido objeto de un sinnúmero de investigaciones, pero se ha dado muy poca atención a la fauna de tortugas del continente. La Cordillera de los Andes separa la fauna de tortugas El Ecuador está dividido en cuatro regiones geográficas principales: costa, sierra, oriente y archipiélago de Galápagos. Las tortugas terrestres o de agua dulce se

Southeastern Naturalist, Jun 14, 2023

Conservation Biology, 2012

Because particular life history traits affect species vulnerability to development pressures, cro... more Because particular life history traits affect species vulnerability to development pressures, cross-species summaries of life history traits are useful for generating management guidelines. Conservation of aquatic turtles, many members of which are regionally or globally imperiled, requires knowing the extent of upland habitat used for nesting. Therefore, we compiled distances that nests and gravid females had been observed from wetlands. Based on records of ≥ 8 000 nests and gravid female records compiled for 31 species in the United States and Canada, the distances that encompass 95% of nests vary dramatically among genera and populations, from just 8 m for Malaclemys to nearly 1 400 m for Trachemys. Widths of core areas to encompass varying fractions of nesting populations (based on mean maxima across all genera) were estimated as: 50% coverage = 93 m, 75% = 154 m, 90% = 198 m, 95% = 232 m, 100% = 942 m. Approximately 6-98 m is required to encompass each consecutive 10% segment of a nesting population up to 90% coverage; thereafter, ca. 424 m is required to encompass the remaining 10%. Many genera require modest terrestrial areas (< 200 m zones) for 95% nest coverage (Actinemys,

FIGURE 4. Illustration from Schoepff (1792: pl. 3, figs. 4–5), showing the holotype of Testudo sc... more FIGURE 4. Illustration from Schoepff (1792: pl. 3, figs. 4–5), showing the holotype of Testudo scripta Thunberg in Schoepff 1792 (also Testudo scabra L. sensu Thunberg in Schoepff) (presently Trachemys scripta scripta). On the plate these figures are labeled "Test. scripta Thunb." and the specimen is clearly a hatchling. The specimen itself was originally catalogued as Testudo scripta by Thunberg sometime between 1785 and 1792 and donated by him to the Uppsala University Museum of Zoology, and it is still there as a badly dried and misshaped specimen now catalogued as UUZM Types 7455 (see Fig. 7).

Herpetological Review, 1986

TRACHEMYS SCRIPTA CATASPILA (Huastecan Slider). REPRODUCTION. A gravid female Trachemys scripta c... more TRACHEMYS SCRIPTA CATASPILA (Huastecan Slider). REPRODUCTION. A gravid female Trachemys scripta cataspiia was cap tured southeast of Rancho Nuevo, Municipio de Aldama, Tamaulipas. Mexico (23° 1V N,. 97° 47' W) on 24 June 1981. The female had straight, mid-line lengths of 224 mm (cara pace) and 205 mm (plastron), and a mass of approximately 1800 g. On 1 July, oxytocin injections totalling 1.4 cc (20 I.U./cc) were administered over a three hour period accord ing to procedures modified from those of Ewert and Legler (1978. Herpetologica 34:

Acta Herpetologica, 2018

Chicken turtles ( Deirochelys reticularia ) are generally characterized as having atypical reprod... more Chicken turtles ( Deirochelys reticularia ) are generally characterized as having atypical reproductive characteristics relative to other sympatric emydids. However, the comparatively understudied western chicken turtle ( D. r. miaria ) has been shown to exhibit some reproductive characteristics that differ from the other subspecies. Therefore, we examined clutch and egg sizes from six D. r. miaria (13 clutches) in Oklahoma and compared the results to values that have been reported for the other two subspecies. Females nested up to three times per year, with clutches ranging from 8-13 eggs per clutch (mean = 10.9). The eggs were 19.4-25.3 mm wide (mean = 22.2 mm). These values are greater than the means reported for the other subspecies, but the differences were not statistically significant.

Southeastern Naturalist, 2008

I describe terrestrial foraging behavior in Trachemys scripta elegans (Red-eared Slider) and Grap... more I describe terrestrial foraging behavior in Trachemys scripta elegans (Red-eared Slider) and Graptemys pseudogeographica kohnii (Mississippi Map Turtle), two species of semiaquatic turtles. I observed specimens of Red-eared Slider on two occasions in two different locations climbing onto the bank of a stream and consuming grass blades (Luziola fl uitans [Southern Watergrass] and Eragrostis hypnoides [Teal Lovegrass]), which were swallowed when the turtles returned to the water. These observations included both adult males and females. In addition, I observed on one occasion two juvenile Mississippi Map Turtles leave the water and forage on plants on a stream bank also used by Red-eared Sliders. Individuals of Mississippi Map Turtles passed by grass and consumed the sprouts of a dicot (Ludwigia decurrens [Wingleaf Waterprimrose] and/or Pentodon pentandrus [Haleʼs Pentodon]).

Our planet faces many serious environmental problems, among them global climate change, pollution... more Our planet faces many serious environmental problems, among them global climate change, pollution, soil erosion, and toxic waste disposal. At Conservation International (CI), we believe that there is one problem that surpasses all others in terms of importance because of its irreversibility, the extinction of biological diversity. Conservation efforts still receive only a tiny fraction of the resources, both human and financial, needed to get the job done. As a result of this, we must use available resources efficiently, applying them to those places with the highest concentrations of diversity which are at most immediate risk of disappearing. CI uses a strategic, hierarchical approach for setting conservation investment priorities. At a global level, we have targeted the "hotspots," 15 tropical areas that hold a third or more of all terrestrial diversity and are at great risk. Our global priorities also focus on major tropical wilderness areas and the "megadiversity" country concept, which highlights the importance of the national entities that harbor high biodiversity. We are now undertaking a series of priority-setting exercises for other major categories of ecosystems, among them marine systems, deserts, and dry forests. The next level of priority setting is the bio-regional workshop, a process where experts assemble their combined knowledge of an area to map regional conservation priorities using CI's geographic information system (CISIG). We have also taken a taxon-based approach, working with the Species Survival Commission of IUCN to produce action plans for key groups of organisms. These priority-setting exercises provide the scientific underpinning for urgent conservation decisions in hotspot regions. Although the hotspots we have identified occupy less than 3-4 percent of the land surface of the planet, they still cover several million square kilometers, only small areas of which have been properly inventoried. To fill the gaps in our regional knowledge, CI created the Rapid Assessment Program (RAP) in 1989. RAP assembles teams of world-renowned experts and host country scientists to generate first-cut assessments of the biological value of poorly known areas. An area's importance can be characterized by its total biodiversity, its degree of endemism, the uniqueness of an ecosystem, and the degree of risk of extinction. As a conservation tool, RAP precedes long-term scientific inventory. When satellite images of an area targeted for a RAP assessment are available, the team consults them prior to a trip to determine the extent of forest cover and likely areas for exploration. Once in-country, the scientists make overflights in small planes or helicopters to identify forest types and points for field transects. Ground travel often requires a combination of vehicles, boats, pack animals, and foot travel to get the team to remote sites where few, if any, roads exist. Trips last from two to eight weeks. On each trip, in-country scientists form a central part of the team. Local experts are especially critical to understanding areas where little exploration has been undertaken. Subsequent research and protection of habitats following a RAP trip depends on the initiatives of local scientists and conservationists. The RAP concept was born during a field trip by Murray Gell-Mann of the MacArthur Foundation, Spencer Beebe, one of CI's founders, and Ted Parker, current leader of the RAP team. RAP has been generously funded by the John D.

We conducted a preliminary survey of the herpetofauna in Upper Niger National Park at the end of ... more We conducted a preliminary survey of the herpetofauna in Upper Niger National Park at the end of tlie dry season in 2002. Museum holdings and literature records from localities within the park were combined with our data to obtain an overall picture of the herpetofauna. The park contains a mosaic of forest and sa\'anna that straddles the Niger River. Twenty-two species of amphibians and 34 species of reptiles were recorded from the park; four species of amphibians and two of reptiles are the first records from Guinea. Seven species of reptiles are listed as threatened by the lUCN Red List or CITES, but according to the Global Amphibian Assessment, none of the amphibians is threatened. Stomach contents of an arboreal colubrid snake included a species of bat (Mops condylurus), which represents the first confirmed record from Guinea. Conservation of the park is paramount because: 1) it is the only protected area containing dry forest in Guinea; 2) gallery forest provides suitable habitat for amphibian, reptile, and mammal species otherwise restrictecl to tropical rainforest elsewhere in West Africa; and 3) .several species of threatened reptiles endemic to West Africa are in the park.

Genetica, 1986

The present study examined karyotypes of 16 genera and, along with previous reports, chromosomal ... more The present study examined karyotypes of 16 genera and, along with previous reports, chromosomal data are now available for 18 of the 23 recognized batagurine genera. There are no karyotypic data available for the members of McDowell's (1964) Hardella complex. The Batagur, Heosemys and Geoemyda complexes re tain the hypothesized primitive karyotype for the subfamily (2n=52). All the genera in these three complexes have been examined except Batagur and Annamemys. The Orlitia complex is karyotypically distinct with 2n = 50 and the NOR located terminally on a large microchromosome. The genus Malayemys inclusion in the Batagur complex is not supported. Malay emys is characterized by a 2n = 50 karyotype, with the NOR located interstitially on a large microchromosome. The Malayemys complex is erected to contain this genus at a point intermediate between the Orlitia complex and the subfamily Emydinae. Malayemys and the emydines are karyotypically indistinguishable. The Neotropical genus Rhinoclemmys (Geoemyda complex) differs only slightly from the primitive batagurine karyotype in the position of the NOR. The species R. funerea and R. punctularia further differ in possessing one less metacentric macrochomosome. An interest ing situation involves two subspecies of/?, punctularia. The nominate subspecies is characterized by a 2n=56 karyotype, while R. p. melanosterna reportedly has a 2n=52 karyotype. Such a difference is interpreted as indicative of genetic differentiation between the two forms of a magnitude inconsistent with considering them as conspecific. Taken together with zoogeographic considerations, the karyotypic difference between the forms R. p. punctularia and R. p. melanosterna seem sufficient to warrant species distinction for R. melanosterna as previously suggested by Pritchard (1979b).

Chelonian Conservation and Biology, 2008

The species-level designation of the Mexican softshell turtle, Apalone atra, has been repeatedly ... more The species-level designation of the Mexican softshell turtle, Apalone atra, has been repeatedly challenged, yet no DNA evidence has been collected. We conducted field studies of all the drainages of the Cuatro Ciénegas basin, and the only pure morphological population of A. atra found was in Tío Candido, the type locality for the species. One nuclear intron known to show species-level divergence in the family Trionychidae, 2 nuclear genes, and a mitochondrial gene revealed little molecular divergence for A. atra when compared with A. spinifera emoryi from the Rio Grande. Further, no reciprocal monophyly of the mitochondrial gene tree was seen between A. atra and A. s. emoryi morphotypes. A. atra (TC36) A. atra (TC38) A. s. emoryi (TXsc) A. s. emoryi (NMrg) A. s. pallida (CME63) A. atra (TC36) 0 A. atra (TC38)

Herpetological Review, 2011

Journal of North American Herpetology, 2014

The Mediterranean Gecko, Hemidactylus turcicus, is known to have colonized nearly every state in ... more The Mediterranean Gecko, Hemidactylus turcicus, is known to have colonized nearly every state in the southern United States. In Louisiana, the Mediterranean Gecko has been documented in many of the southern parishes, but records for the northern portion of the state are limited. We sampled northern Louisiana parishes to document the presence of the Mediterranean Gecko. We sampled a total of 21 parishes in northern Louisiana and found geckos in 17 of those parishes, 16 of which represent new distribution records for the species. This indicates a significant range expansion of this introduced species throughout northern Louisiana. Geckos were found across a temperature range of 14.0–28.0°C and had a strong association with buildings. The species’ affinity for anthropogenic association and the continual nature of anthropogenic expansion facilitate the high vagility of this species. The result is a successful colonization throughout much of Louisiana and likely continued range expansion...