Final Draft

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The Asiatic soft shelled turtle, or Amyda cartilaginea goes through a life cycle similar to many other turtles around the world. It begins its life by hatching from a clutch of eggs layed in sand along a body of water. These clutches range in size from four to eight eggs depending on the size and age of the female[1]. On average the incubation period for these turtles can range between 130 to 140 days, something which is greatly dependent on the climate for not only the rate of incubation but also the sex of the majority of these turtles. Temperature has a great influence on what sex the turtle will become, with females being born around 30 degrees Celsius and males at 25 degrees Celsius[2]. Once hatched the young turtles must race to the water in order to prevent being eaten. Monitor lizards along with crows and serpent eagles are known to eat these young turtles.

The turtles that escape these early threats will continue to grow and develop into sexually reproducing adults, for females this takes around 20 months[3]. Once sexually mature, the turtles can produce up to four clutches of eggs a year[4]. This depends on how temperate the year had been seeing as the mating cycles of these turtles rely on the dry seasons seeing as these are the only times the river banks are exposed enough for them to lay eggs[5]. Although it is understood that these turtles can live very long lives it is not understood how long they live for. This in part is due to the fact that many of these turtles are caught as a food source with the larger turtles being more desirable since they produce more meat[6].

Rough Draft

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The Asiatic soft shelled turtle, or Amyda cartilaginea goes through a life cycle similar to many other turtles around the world. It begins its life by hatching from a clutch of eggs layed in sand along a body of water. These clutches range in size from four to eight eggs depending on the size and age of the female. On average the incubation period for these turtles can range between 130 to 140 days, something which is greatly dependent on the climate for not only the rate of incubation but also the sex of the majority of these turtles. Temperature has a great influence on what sex the turtle will become, with females being born around 30 degrees Celsius and males at 25 degrees Celsius. Once hatched the young turtles must race to the water in order to prevent being eaten. Monitor lizards along with crows and serpent eagles are known to eat these young turtles.

The turtles that escape these early threats will continue to grow and develop into sexually reproducing adults, for females this takes around 20 months. Once sexually mature the turtles can produce up to four clutches of eggs a year, depending on how temperate the year had been seeing as the mating cycles of these turtles is temperature dependent. Although it is understood that these turtles can live very long lives it is not understood how long they live for. This in part is due to the fact that many of these turtles are caught as a food source with the larger turtles being more desirable since they produce more meat.

Outline

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The early life of these turtles

average incubation time for them

  • Incubation period depends on microhabitat conditions and may last from 2–4.5 months (Auliya...et all)
  • Incubation period can be between 130-140 days (Dun). <Probably use this data since the source is more reputable>

    average time taken for animal to reach sexual maturity

  • Females mature at 20 months

Clutch size/ mateing cycle

  • Each year, the Southeast Asian softshell terrapin nests three or four times(Auliya)
  • I have seen some variance in clutch size though I found that a majority of my sources claim 4-8 eggs are in each clutch
  • One thing which I read a lot was the fact that cluch size can vary based on the age of the female with older females producing more eggs

Major threats to the animal at this time (possible predators, diseases..ect)

  • monitor lizards seem to prey on them when they hatch and before as well along with crows and serpent eagles (Arkive)
  • Humans are also a threat taking eggs for Chinese medicine (Arkive)

The later development of these animals

At what age they reach sexual maturity at

  • It says females reach sexual maturity at 20 months (Asia Turtle)
  • females between 8-10 years old, males between 4-5 years old.

how long do they typically live

  • I can't seem to find much information on this

What factors influence their lifespan

  • One thing I found is that they are exploited fairly heavily for food, and are often caught in net and the such.
  • I found in several of the sources listed below that the people that are payed for these turtles are done so by weight. this would explain why there is so little information on the max life span of these creatures

Bibliography

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Vaught,2015,Amyda cartilaginea Black-rayed Soft-shelled Turtle, Asiatic Softshell Turtle, http://animaldiversity.org/accounts/Amyda_cartilaginea/

Asia Turtle Conservation Network, 2006, http://www.asianturtlenetwork.org/field_guide/amyda_cartilaginea.htm

Dun Marilyn 2010, A Field Guide To The Reptiles Of South-East Asia, https://books.google.com/books?id=5hRpBwAAQBAJ&pg=PA176&lpg=PA176&dq=amyda+cartilaginea+habitat&source=bl&ots=mwnBGCNZUf&sig=LIemHhYeORO_veGQRL2HEu-iXvE&hl=en&sa=X&ved=0ahUKEwiA8p-H2pXQAhVp2IMKHWlQABw4HhDoAQgnMAI#v=onepage&q=%20Amyda%20cartilaginea&f=false

California Academy of Science, 2016, http://www.inaturalist.org/taxa/73600-Amyda-cartilaginea

Auliya, M., van Dijk,P.P.,Moll, E.O., and Meylan, P.A. 2016, Asiatic Softshell Turtle, Southeast Asian Softshell Turtle, http://www.iucn-tftsg.org/amyda-cartilaginea-092/

Asiatic Soft-shell Turtle Amyda cartilaginea in Indonesia: A Review of its Natural History and Harvest Mirza D. Kusrini, Ani Mardiastuti, et al. http://www.academia.edu/11131519/Asiatic_Soft-shell_Turtle_Amyda_cartilaginea_in_Indonesia_A_Review_of_its_Natural_History_and_Harvest

Asia Turtle Conservation Network, 2006, http://www.asianturtlenetwork.org/field_guide/amyda_cartilaginea.htm

Encyclopedia of Life, 2016 (last updated) http://eol.org/pages/795946/overview

Arkive.org entry, http://www.arkive.org/southeast-asian-soft-terrapin/amyda-cartilaginea/

Fritz, U., Gemel, R., Kehlmaier, C., Vamberger, M., and P. Prashag. 2014. Phylogeography of the Asian softshell turtle Amyda cartilaginea (Boddert 1770): evidence for a species complex. Vert. Zool. 64 (2): 229-243.http://www.senckenberg.de/files/content/forschung/publikationen/vertebratezoology/vz64-2/09_vertebrate_zoology_64-2_fritz_229-243.pdf

  1. ^ Das, Indraneil (2015-06-18). A Field Guide To The Reptiles Of South-East Asia. Bloomsbury Publishing. ISBN 9781472920584.
  2. ^ "Amyda cartilaginea (Black-rayed Soft-shelled Turtle, Asiatic Softshell Turtle)". Animal Diversity Web. Retrieved 2016-12-13.
  3. ^ "Amyda cartilaginea field guide - Asian Turtle Conservation Network". www.asianturtlenetwork.org. Retrieved 2016-12-13.
  4. ^ "Southeast Asian Softshell Turtle - Amyda cartilaginea - Overview - Encyclopedia of Life". Encyclopedia of Life. Retrieved 2016-12-13.
  5. ^ "Amyda cartilaginea (Black-rayed Soft-shelled Turtle, Asiatic Softshell Turtle)". Animal Diversity Web. Retrieved 2016-12-13.
  6. ^ Mardiastuti, Ani; Kusrini, Mirza. "Asiatic Soft-shell Turtle Amyda cartilaginea in Indonesia: A Review of its Natural History and Harvest". {{cite journal}}: Cite journal requires |journal= (help)