Mesoamerican River Turtle
Encyclopedia
The Central American river turtle or Mesoamerican river turtle (Dermatemys mawii) locally known as the "hickatee" or "tortuga blanca"-(white turtle) is the only living species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Dermatemydidae. Its closest relatives are only known from fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

s

It is a nocturnal
Nocturnal animal
Nocturnality is an animal behavior characterized by activity during the night and sleeping during the day. The common adjective is "nocturnal"....

, aquatic turtle
Turtle
Turtles are reptiles of the order Testudines , characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield...

 that lives in larger river
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

s and lake
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

s in Central America
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

, from southern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

 to northern Honduras
Honduras
Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...

. It is one of the world's most heavily exploited turtles and is classified a Critically Endangered species by the IUCN and is listed as Endangered under the U.S. Endangered Species Act
Endangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...

. The Central American river turtle has been intensely harvested, primarily for its meat, but also for its eggs and shell. The turtle has been nearly eliminated from much of its former range in southern Mexico.

Dermatemys species are fairly large turtles, attaining a maximum size of 65 cm (25 inches) in carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...

 length, and they can weigh in the range of 20 kg (44 lbs).

They have a flattened carapace, that is usually a solid grey
Grey
Grey or gray is an achromatic or neutral color.Complementary colors are defined to mix to grey, either additively or subtractively, and many color models place complements opposite each other in a color wheel. To produce grey in RGB displays, the R, G, and B primary light sources are combined in...

 or almost black
Black
Black is the color of objects that do not emit or reflect light in any part of the visible spectrum; they absorb all such frequencies of light...

 in color. Their plastron is normally cream colored. In juveniles, a distinctive keel is found down the center of the carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...

, and the outer edges have serrations. These features are lost as the turtle ages. Its skin is predominantly the same color as the shell, with red
Red
Red is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths of light discernible by the human eye, in the wavelength range of roughly 630–740 nm. Longer wavelengths than this are called infrared , and cannot be seen by the naked eye...

dish or peach colored markings around the neck and underside. Males can be differentiated from females by yellow markings on either side of their head, and a longer, thicker tail
Tail
The tail is the section at the rear end of an animal's body; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals, reptiles, and birds...

.

Reproduction

Mating and nesting occurs in the fall, from September to November. Females lay clutches of 6-20 eggs
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...

 on the banks of waterways that they otherwise would not normally be able to reach without the flooding caused by the seasonal rainfall.

Conservation status

Rarely found in captivity
Captivity (animal)
Animals that live under human care are in captivity. Captivity can be used as a generalizing term to describe the keeping of either domesticated animals or wild animals. This may include for example farms, private homes and zoos...

, the river turtle has been over-hunted because of its value in the food market. Even the hatchling
Hatchling
In oviparous biology, a hatchling is the newborn of animals that develop and emerge from within hard-shell eggs. The offspring of birds are often hatched naked and with their eyes closed. The hatchling relies totally on its parents for feeding and warmth. Hatchlings precede nestlings in the chick's...

s and eggs are sold as food. The species' normally passive nature makes them relatively easy to catch. As such, they have been listed as a CITES Appendix II
Convention on the International Trade in Endangered Species of Wild Flora and Fauna
CITES is a multilateral treaty, drafted as a result of a resolution adopted in 1963 at a meeting of members of the International Union for Conservation of Nature...

 to prevent exportation, and there are local laws in place to prevent them from being hunted.

Conservation efforts in Belize

On Dec. 7th, 2010, the first hickatee conservation forum and workshop was held at the University of Belize, Belmopan campus presented by the Turtle Survival Alliance (TSA), in collaboration with the Belize Foundation for Research and Environmental Education (BFREE), the Environmental Research Institute at UB and the Belize Fisheries Department. The purpose of the workshop was to bring together members of the scientific community, government officials, NGO’s and civil society to share information regarding the critically endangered hicatee turtle (Dermatemys mawaii).

The Turtle Survival Alliance is an international conservation partnership that is committed to zero turtle extinctions. Focusing on species ranked critically endangered, the TSA supports projects or programs around the world with an emphasis on Madagascar and Asia. The mission of the TSA is: Transforming passion for turtles into effective conservation action through a global network of living collections and recovery programs. An important aspect of the meeting was to share the results of a recent country-wide survey of Hickatee and that was conducted in April–May of this year and was supported by TSA in conjunction with local NGO’s, and civil society under the authority of the Belize Fisheries Department. Results of the survey indicated the population is clearly headed towards extinction in Belize unless conservation measures are put in place. Local population extinctions have been documented, and current harvesting rates have been determined to be unsustainable. When compared to previous surveys, the most recent survey indicates that overall populations of Hicatee continue to decline across the nation.

Captive turtle breeding program in Belize

A study, managed by the Turtle Survival Alliance (TSA) and conducted on Belize Foundation for Research and Environmental Education (BFREE) property in Belize, began in early 2011 and is a low maintenance operation focused on generating Dermatemys food plants, while exploring husbandry details such as egg laying and incubation. Located in southern Belize along the Bladen River, BFREE encompasses 1200 acres (4.9 km²) of forest and is situated among four protected areas (Bladen Nature Reserve
Bladen Nature Reserve
Bladen Nature Reserve is a landscape of caves, sinkholes, pristine streams and rivers, undisturbed old growth rainforest and an abundance of highly diverse flora and fauna which includes a great deal of rare and endemic species....

, Cockscomb Basin Jaguar Reserve
Cockscomb Basin Wildlife Sanctuary
The Cockscomb Basin Wildlife Sanctuary is a nature reserve in south-central Belize established to protect the forests, fauna and watersheds of an approximately 400 square kilometre area of the eastern slopes of the Maya Mountains...

,Deep River Forest Reserve and Maya Mountain Forest Reserve), which enhances the possibility of a successful breeding program.

The goal of the program is to generate hatchlings and release them in order to repopulate already depleted wild populations and, ultimately, relieve pressures of local populations. The program has the potential to be expanded once it is determined that the species can be reliably reproduced in good numbers in captivity.

External links


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