Abstract - Macrochelys temminckii (Alligator Snapping Turtle) were commercially harvested for consumption, and Louisiana was the last state to ban this commerce. There are no demographic studies on healthy populations within the state. We conducted trapping surveys at Black Bayou Lake National Wildlife Refuge near Monroe, LA, from 2004 to 2020. We captured 90 individual Alligator Snapping Turtles over 17 years. We compared survey data between the 2004–2005 survey period and the 2019–2020 survey period to estimate changes in demography. We found the population to be stable, but the low number of juveniles captured raises concerns for the future of the population. Continued monitoring is recommended to evaluate the stability of the population.

We report nest success for 16 Alligator Snapping Turtle nests oviposited at Black Bayou Lake National Wildlife Refuge in 2008 and 2009. We split each clutch into 2 portions for field and laboratory incubation. The field portion was protected from mammalian depredation. For each nest, we report both pipping and hatching success. Our total observed levels of pipping and hatching success were 55.9% and 47.7%, respectively. We obtained a hatching success rate of 85.8% in the lab. Reasons for the difference in hatching success between the field and lab included both abiotic and biotic factors in the nest environment, such as flooding, temperature, and invertebrate predators.

With the conservation status of Macrochelys (alligator snapping turtles) being examined at the national level, our objective was to compile categorical data on threats from anthropogenic interactions. We included information from (1) author-collected anecdotes on human-turtle interactions and (2) radiographs to assess the prevalence of ingested fishing hooks. We placed 173 interactions involving 192 incidents into 9 IUCN threat categories and found bycatch involving fish hooks to be 4 times more numerous than the second-most numerous threat, turtle persecution. Fishing bycatch resulted in a high proportion of turtle mortalities (39%), and bycatch incidents in several cases preceded the highest-mortality threat (53%), persecution of individuals involving shooting or blunt trauma. We recommend fishing bycatch-mitigation measures and educational efforts to help conserve Macrochelys.

The Brown Wood Turtle, Rhinoclemmys annulata (family Geoemydidae, subfamily Rhinoclemmydinae), is a medium-sized turtle (maximum straightline carapace length [SCL] to 226 mm), that is largely terrestrial and primarily occurs in rainforest areas in Caribbean drainages of Central America from Honduras to northern Colombia, and in Pacific drainages from eastern Panama south to Ecuador.In Ecuador, the species occurs in dry forest areas as well.The known elevational range is from sea level to 920 m.The species is monotypic, without subspecies, and demonstrates substantial variability in carapace coloration within populations.There is modest sexual size dimorphism, with males reaching a maximum SCL of 202 mm, and females up to 226 mm.Females lay one large elongate egg measuring approximately 71 x 37 mm and 48-49 g, with a mean hatchling SCL of 63.9 mm.The ecology of R. annulata is poorly studied, and its population status is unknown.The greatest threat faced by this species is habitat destruction, although the degree and impact of this threat remains unknown.It is also sometimes utilized as a local pet and food source by several indigenous and rural populations.Trade into the international pet market appears to be minimal.The species has been recorded from several protected areas within its range, but assessments of its threats, conservation status, and population trends are needed.distribution.-Colombia, Costa Rica,

Alligator snapping turtles (genus Macrochelys) are the largest freshwater turtles in North America. Despite strong interest in their conservation, we still lack a comprehensive understanding of their natural history, including behaviors associated with terrestrial activity. We reviewed the literature and solicited unpublished observations of terrestrial movements of these highly aquatic turtles. We compiled 206 observations of terrestrial activity from 9 states. The majority of observations were associated with nesting behavior. Observations expanded our knowledge regarding the spatial extent and timing of terrestrial movements and the nesting season. In addition, we compiled observations of terrestrially foraging animals, as well as males and juveniles traveling overland and crossing roads. Collectively, this information clarifies the extent of terrestrial movement by Macrochelys, behaviors that should be considered in conservation plans.

Herein we briefly provide a background context for and summary overview of the articles comprising this special issue of the Southeastern Naturalist on Macrochelys spp. (alligator snapping turtles). We also make a case for standardization in collecting and reporting morphometric data on these species, clarify the current taxonomic status within the genus, provide updated information on the distribution of Macrochelys in the US, and include a current bibliography and categorical analysis over time of the rapidly growing collection of literature focused on these iconic turtles.

The lingual lures of Macrochelys (alligator snapping turtles) are believed to be the only prey-capturing lures within the mouths of modern reptiles. To date, no formal assessment of lure condition in Macrochelys has been published, and few researchers record lure data. Herein, we report damaged or missing lures from 25 Macrochelys temminckii (Alligator Snapping Turtle; 7 adults, 18 juveniles) from a sample of more than 2000 lure assessments in 4 states, indicating this is a rare occurrence. We also describe lingual lure color observed in these assessments and introduce standardized terminology and color categories. We suggest researchers record data on the condition and coloration of the lingual lure to further our understanding of this ecological and evolutionary adaptation.

Few long-term demographic studies have been conducted on freshwater turtles of South America, despite the need for this type of inquiry to investigate natural variation and strengthen conservation efforts for these species. In this study, we examined the variation in demography of the Chocoan River Turtle (Rhinoclemmys nasuta) based on a population from an island locality in the Colombian Pacific region between 2005 and 2017. We calculated survival, recapture, and transition probabilities, and the effects of stream substrate and El Niño–Southern Oscillation (ENSO) phases (El Niño, Neutral, La Niña) on these variables using a multi-state model. We found differences in survival probabilities between ENSO phases, likely as a consequence of an increase in flood events. In addition, we found support for survival being greater in muddy streams than rocky streams, possibly because it is easier to escape or hide in mud substrates. Recapture probabilities varied by life stages; differences in the probability of recapture between size classes were associated with the high fidelity to territories by adults. The present increases in frequency and severity of El Niño and La Niña may exacerbate the consequences of climatic regimes on natural populations of turtles by increasing the mortality caused by drastic phenomena such as floods.

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.

We collected data on several aspects of the reproductive biology of the Chocoan River Turtle (Rhinoclemmys nasuta) as part of a long-term demographic study (2005-2015), along the Pacific coast of the department of Valle del Cauca in Colombia. We palpated 659 females and found 77 gravid, with two peaks in the proportion of females gravid, one between May and June, and another from October to December; there was a significant correlation between the monthly proportion gravid and the monthly amount of precipitation (Spearman rank correlation , ). We obtained 13 eggs (mean length = 63.8 mm, mean width = 35.4 mm, mean weight = 45.8 g). Using egg volume as a general indicator of size, there was no significant relationship with female size. To induce oviposition, oxytocin, prostaglandin, or a combination of the two was injected into 37 gravid females with a success rate of 48.6%. We determined the duration of incubation for two individuals as 133 and 135 days. With this information, we fill some gaps in the knowledge of reproductive ecology of this species; however, the sample size is very low and primarily comes from a single insular population and therefore it is important to continue studies on aspects of reproductive ecology such as those evaluated in this study and other topics like sex determination.

We collected reproductive data from six female Deirochelys reticularia miaria in northeastern Louisiana that were collected in January 1999, June 2001, and May of both 2002 and 2003. One female collected in late January was dissected and found to contain two size classes of enlarged ovarian follicles. Five additional females collected on land in May or June were all gravid; three of them were caught while digging a nest. Mean clutch size was 10.6 and mean egg size was 37.68 x 22.88 mm, with a mass of 11.69 g. The mean incubation period for 32 eggs was 84 days, and hatchling measurements were mean carapace length of 31.67 mm and mass of 8.32 g.

The objective of our study was to review and quantify the level of knowledge of the biology of tortoise and freshwater turtle species of Colombia based on studies conducted in the country. We used the resulting rankings in knowledge, in combination with IUCN threat category, presence in protected areas, and endemism, to propose conservation priorities. This process also allowed us to evaluate which aspects of turtle biology have been least studied. Four species obtained total values of zero or one over the 21 knowledge criteria employed, so they were ranked as the highest priority for research based on the lack of knowledge of their biology: Black-lined Toad-headed Turtle (Mesoclemmys raniceps), Amazon Toad-headed Turtle (Mesoclemmys heliostemma), Gibba Toad-headed Turtle (Mesoclemmys gibba), and Dunn's Mud Turtle (Kinosternon dunni). Moreover, species in the family Chelidae in general were found to have limited levels of knowledge, which makes this group a priority for investigation. Evaluation of the distinct criteria used in the knowledge assessment revealed that the best-known criteria were geographic distribution (modeled), presence or absence in protected areas, and clutch size. The most poorly known biological characteristics, which constitute research priorities, are the frequency of nesting, longevity and generation time, and population parameters. According to the criteria used, the priority species for conservation were the Magdalena River Turtle (Podocnemis lewyana), Dahl's Toad-headed Turtle (Mesoclemmys dahli), K. dunni, and Maracaibo Wood Turtle (Rhinoclemmys diademata), three of which are endemic or semiendemic (R. diademata only occurs in Colombia and Venezuela), followed by two species of Mesoclemmys.

Population parameters and habitat preference of the Chocoan river turtle Rhinoclemmys nasuta (Testudines: Geoemydidae). The Chocoan river turtle (Rhinoclemmys nasuta) is considered endemic to the Chocó region, near threatened (NT) worldwide and data deficient (DD) in Colombia. Due to lack of information about their demographics in environments with different degrees of human disturbance research was carried out to fill these gaps in three locations on the Pacific coast of the Department of Valle del Cauca (Isla Palma, San Pedro and Playa Chucheros). Based on six bimonthly capture-recapture events, population parameters were calculated, including density, population size and structure, and the likelihood of survival and capture for males, females and juveniles. Additionally, the population density was associated with abiotic (depth, access to land, number of hiding places, substrate) and biotic characteristics (vegetation cover and percentage of parasitism) of the habitat at two scales (local and streams). In total 10 there were 604 captures of 477 individuals, 371 individuals at Isla Palma, 61 individuals at San Pedro and 45 individuals at Playa Chucheros. The highest population density and the highest probability of survival were recorded in the locality of Isla Palma, probably due to a smaller amount of associated predators and a lower rate of infestation by ectoparasites. In the island locality, the population was dominated by the juvenile age class, whereas in continental localities the population was dominated by adult individuals. In all locations the sex ratio was dominated by females, a condition related to the difference in age of maturation or temperature sex determination, between sexes. The species preferred streams with less vegetation, many hiding places, shallow water and a predominance of rock. Although it can be considered that the species is tolerant to disturbed environments, human disturbance affects the age distribution of the population, which can eventually lead to population reductions.

Este documento es de interes tanto para los investigadores de las diversas instituciones que laboran en Colombia, como para las autoridades ambientales, incluidos los tomadores de decisiones y la sociedad en general. La construccion de estas estrategias (2015-2020), representa una guia de trabajo u hoja de ruta que busca constituirse en una herramienta para que cualquier persona u organizacion que quiera propender por la conservacion de las tortugas tenga un referente de cuales son las necesidades y prioridades de trabajo en el pais respecto a este grupo. Esperamos que este esfuerzo sea bien recibido por todos los sectores del pais y muy especialmente por las autoridades ambientales regionales y de desarrollo sostenible, y se vea reflejado en mayores inversiones para la conservacion de este valioso recurso.

The Chocoan River Turtle, Rhinoclemmys nasuta (Geoemydidae), is a species of great importance due to its limited geographical distribution and threat status. In Colombia it is considered in the category data deficient (DD) and globally as a near-threatened species (NT). In this study we assessed the population density, variation in the demographic structure and population size, and morphometric variation in two localities. One island population has no human disturbance and the other, mainland locality is human-influenced. Population density was 6.3 times greater in the insular locality, which corresponds with the absence of some predators and human disturbance at this location. Additionally, there was no significant difference between localities in demographic structure and size classes, which may reflect that there is no removal of individuals for consumption or use as pets in the mainland population. On the other hand, body size was smaller on the island, a phenomenon that may be explained by a tendency of species to dwarfism in insular environments, or an effect of increased intraspecific competition. To clarify whether differences in population density and body size are attributable to island effects or to the difference in the degree of human disturbance between the two populations it will be necessary to sample at other locations on the mainland with different degrees of human disturbance. However, it is important to stress the importance of Isla Palma as a site for regional conservation of R. nasuta.

We describe the subsistence exploitation of an entire turtle fauna in Esmeraldas Province, Ecuador. We collected firsthand accounts and witnessed a number of capture techniques used by rural Afroecuadorian and Chachi inhabitants of the Cayapas-Santiago river basin. The diversity of techniques indicated a practical knowledge of the ecology of the species. Chelydra acutirostris, Kinosternon leucostomum, Rhinoclemmys annulata, melanosterna, and R. nasuta were captured and eaten. Poziando involved cleaning pools in a stream bed during the relatively dry season by removing live plants, organic detritus, and then seining with baskets; we observed R. melanosterna and K. leucostomum captured in this way. Pitfall traps baited with fruit were used to catch R. melanosterna during forays on land. Basket traps (“canasto tortuguero”) with a wooden slat funnel across the opening are floated with balsa lashed to the sides. Banana or Xanthosoma leaf bait in the basket traps caught R. melanosterna, R. nasuta, and K. leucostomum. Marshy areas were probed for R. melanosterna and K. leucostomum. Direct capture by hand was also common. Turtles were relished as food items; all turtles captured were consumed, usually in soup or stew. Use of turtles for food in the region was pervasive, perhaps because fish and game populations were depleted.

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 throughout the southern United States.

We describe the subsistence exploitation of an entire turtle fauna in Esmeraldas Province, Ecuador. We collected first-hand accounts and witnessed a number of capture techniques used by rural Afroecuadorian and Chachi inhabitants of the Cayapas-Santiago river basin. The diversity of techniques indicated a practical knowledge of the ecology of the species. Chelydra acutirostris, Kinosternon leucostomum, Rhinoclemmys annulata, melanosterna, and R. nasuta were captured and eaten. Poziando involved cleaning pools in a stream bed during the relatively dry season by removing live plants, organic detritus, and then seining with baskets; we observed R. melanosterna and K. leucostomum captured in this way. Pitfall traps baited with fruit were used to catch R. melanosterna during forays on land. Basket traps ("canasto tortuguero") with a wooden slat funnel across the opening are floated with balsa lashed to the sides. Banana or Xanthosoma leaf bait in the basket traps caught R. melanosterna, R. nasuta, and K. leucostomum. Marshy areas were probed for R. melanosterna and K. leucostomum. Direct capture by hand was also common. Turtles were relished as food items; all turtles captured were consumed, usually in soup or stew. Use of turtles for food in the region was pervasive, perhaps because fish and game populations were depleted.