Chelodina mccordi

Geographic Range

McCord's snakeneck turtle is found exclusively on the tiny island of Rote in Indonesia. It has an extremely limited distribution, with just two known populations on the island, existing on a patch of 70 square kilometers.

• Biogeographic Regions
• australian australian
  • native native

• Other Geographic Terms
• island endemic island endemic

Habitat

Chelodina mccordi is found in shallow freshwater lakes and wetlands, also in adjacent rice fields. Much of their habitat is only wet during the rainy season (December through March), but then are dry for the rest of the year. Turtles that are not in permantly wet habitats will take refuge During the dry season, underneath boulders, rocks, and drifts of leaves in adjacent forests, rather than burrow and remain dormant in the mud. They will not venture into brackish waters of any type.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial
• freshwater freshwater

• Terrestrial Biomes
• forest forest

• Aquatic Biomes
• lakes and ponds
• rivers and streams
• temporary pools

• Wetlands
• marsh marsh
• swamp swamp

• Other Habitat Features
• agricultural agricultural
• riparian riparian

Physical Description

Chelodina mccordi has a somewhat rough shell that is wide and oval, and widens the most toward the tail. The carapace typically is a dull brown color, and the plastron is pale grey colored. Females are typically longer than their male counterparts of the same age, and their mass is comparable to other snake-necked turtles. The head and neck is bumpy with wart-like projections, and like all snake-necked turtles it has a long neck, about two-thirds the length of the carapace. The neck is a darker brown than the shell, with a lighter underside, and the face has ringed eyes.

• Other Physical Features
• ectothermic ectothermic
• heterothermic heterothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• female larger

Development

Incubation takes four months resulting in hatchlings that average 25.5 mm in carapace length. One observation of a wild juvenile indicates that C. mccordi developed three growth rings (annuli) per scute. Such annuli are not found in adults due to weathering making which makes the annuli inaccurate for aging in older turltes

Reproduction

Mating practices for McCord's snakeneck turtle appear to resemble other more common snake-necked turtles. Males pursue their mates from behind. Mating occurs in water, and courtship culminates when the male is able to grasp the carapace of his partner with its claws from behind. The mating system is assumed to be polygnandrous which is common in the family Chelidae .

• Mating System
• polygynandrous (promiscuous) polygynandrous (promiscuous)

Chelodina mccordi nesting habit are not well known, but their movements increase as they transition from water to land after the mating period. Eggs are laid as early as late February, continuing to September, with hatchlings appearing in November, near the start of the rainy season. Chelodina mccordi in captivy have clutch sizes from 9 to 13 eggs. The eggs are average in size relative to other chelids with a size of 29.8 mm in length by 20.1 mm in width. Hatchlings are measured to a mean of 25.5 mm in carapace length.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

As far as is known, provisioning eggs and nesting are the largest parental investment, as is true for chelids generally.

• Parental Investment
• pre-hatching/birth
  • provisioning
    • female

Lifespan/Longevity

The lifespan of Chelodina mccordi remains relatively unknown, as the documentation of an entire lifespan has not been completed. However, other snake-necked turtles have a lifespan of 30 to 40 years.

Behavior

Chelodina mccordi are commonly nocturnal. During the wet season they hunt in shallow freshwater habitats. They may be found on land during the dry seasons. Their only regular movements are from drying aquatic habitats to forest refuges during dry seasons. They are solitary, and aestivate under rocks and boulders during dry periods. Roti island snake-necked turtles are ambush predators, using their long necks to quickly seize prey.

• Key Behaviors
• natatorial natatorial
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• aestivation

Communication and Perception

Communication and perception are not well-known in Chelodina mccordi . It is suspected they use the release of pheromones, touching, and animated movement to attract mates. Visual, auditory, and tactile senses are all utilized in the perception of the surrounding environment.

• Communication Channels
• visual visual
• tactile tactile
• chemical chemical

• Other Communication Modes
• pheromones pheromones

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

The skull and jaw of C. mccordi do not show morphological specializations compared to other snake-necked turtles , and this is believed to indicate that this species is a generalist carnivore or piscivore. Insects, small fish and tadpoles are reported to be of importance to the diet of C. mccordi .

• Primary Diet
• carnivore carnivore
  • piscivore piscivore
  • insectivore insectivore

• Animal Foods
• amphibians
• fish
• carrion carrion
• insects
• mollusks
• aquatic or marine worms

• Plant Foods
• algae

Predation

Roti island snakenecks can produce a foul-smelling musk to discourage predators, and can tuck their neck and head into their shell for protection. Except for humans, adults are they are believed to have few predators. Feral pigs ( Sus scrofa ) are known to eat eggs and adult turtles. Hatchlings might be eaten by wading birds and other medium-sized predators, if present on the island.

• Anti-predator Adaptations
• cryptic cryptic

Ecosystem Roles

Chelodina mccordi might be a top-level predator in the small aquatic habitats it lives in. Parasites for this species have not been described.

Economic Importance for Humans: Positive

Island residents used this species as a minor food source in the past. At present the turtle is in extremely high demand in the pet trade, so much so that this is a very urgent threat to the survival of the species. The capture and sale of these turtles has occurred since the early 1990s.

• Positive Impacts
• pet trade pet trade

Economic Importance for Humans: Negative

There are documented no adverse effects of C. mccordi on humans.

Conservation Status

Chelodina mccordi is in great danger of extinction. It is listed by the IUCN Red List as Critically Endangered. It is listed in CITES Appendix I for zero export quota, meaning it is illegal to transport. In the 5 years following its description as a unique species, excessive harvesting depleted the population to near extinction, and commercial trade in the species collapsed. The numerous trade sanctions have limited the transport of the turtle away from the island of Rote, but the population remains threatened.

Additional Links

Encyclopedia of Life

Contributors

John Myers (author), Indiana University - Purdue University Fort Wayne, Mark Jordan (editor), Indiana University-Purdue University Fort Wayne, George Hammond (editor), Animal Diversity Web Staff.

References

Avise, J., D. Pearse. 2001. Turtle Mating Systems: Behavior, Sperm Storage, and Genetic Paternity. Journal of Heredity , Volume 92. Issue 2: 206-211. Accessed March 25, 2016 at http://jhered.oxfordjournals.org/content/92/2/206.full .

Jarrett, M. 2011. " Chelodina longicollis " (On-line). Animal Diversity Web. Accessed March 29, 2016 at http://animaldiversity.org/accounts/Chelodina_longicollis/ .

Kennet, R., J. Roe, K. Hodges, A. Georges. 2009. Chelodina longicollis (Shaw 1794) – Eastern Long-Necked Turtle, Common Long-Necked Turtle, Common Snake-Necked Turtle.. Pp. 1-8 in Conservation Biology of Freshwater Turtles and Tortoises , Vol. 31. IUCN: Chelonian Research Foundation.

Kuchling, G., W. Fotijne, C. Shepherd. 2013. Consideration of proposals for amendments to Appendices I and II, Chelodina mccordi . Sixteenth Meeting of the Conference of the Parties, Bankok, Thailand. Convention on International Trade in Endangered Species of Wild Fauna and Flora, 16: 1-11. Accessed February 20, 2016 at https://www.fws.gov/international/cites/cop16/cop16-proposal-appendix-i-listing-of-roti-island-snake-necked-turtle.pdf .

Rhodin, A. 1994. A New Species of Chelodina from Roti Island. Chelid Turtles of the Australasian Archipelago , 497: 1-31. Accessed February 20, 2016 at http://www.iucn-tftsg.org/wp-content/uploads/file/Articles/Rhodin_1994a(1).pdf .

Rhodin, A., B. Ibarrondo, G. Kuchling. 2008. Roti Island Snake-Neck Turtle. Conservation Biology of Freshwater Turtles and Tortoises , 5: 008.1-008.8. Accessed February 22, 2016 at http://www.iucn-tftsg.org/wp-content/uploads/file/Accounts/crm_5_008_mccordi_v1_2008.pdf .

Rhodin, A., P. van Dijk, J. Iverson, H. Shaffer. 2010. Turtles of the World, 2010 Update:. Annotated Checklist of Taxonomy, Synonymy, Distribution, and Conservation Status , 2: 000.80-000.120. Accessed February 22, 2016 at http://www.iucn-tftsg.org/wp-content/uploads/file/Accounts/crm_5_000_checklist_v3_2010.pdf .

Rhodin, A. 1995. Status and Conservation of Chelodina mccordi an Isolated and Restricted Freshwater Turtle from Roti Island. International Congress of Chelonian Conservation , 1: 67. Accessed February 20, 2016 at http://www.chelonian.org/wp-content/uploads/file/Rhodin_1996_C_mccordi.pdf .