Saturday, August 24, 2024

Species Profile: Pig-nosed Turtle (Carettochelys insculpta)

Hi, welcome back to animals under threat. Last time, we covered the Central rock-rat which is under threat from habitat destruction and introduced species. Today, we will be covering a species of freshwater turtle that looks more suited to marine life, has an unusual nose, and is under threat from multiple things. Say hello to the Pig-nosed Turtle.

The Pig-nosed Turtle is a freshwater turtle that is the only surviving member of the family Carettochelyidae which was once widespread across Asia and the rest of the world (Eisemberg et al, 2018). With a shell length of 60-70 centimetres, this large grey/brownish freshwater turtle has unique flippers like turtles that live in the ocean and unique placement of its nostrils on the end of a trunk-like snout (dcceew.gov.au, 2024).
(Pig-nosed Turtle swimming by IUCN red list https://www.iucnredlist.org/species/3898/2884984)

(Current distribution range of Pig-nosed Turtle by IUCN RED LIST https://www.iucnredlist.org/species/3898/2884984)

Pig-nosed Turtles that live in New Guinea have a different habitat structure compared to Pig-nosed Turtles that live in Australia. New Guinea Pig-nosed Turtles live in a variety of water habitats ranging from rivers, deltas, lagoons, and swamps in the Southern Lowlands while Pig-nosed Turtles in Australia depend on seasonal, shallow, and continuously flowing waters (Eisemberg et al. 2015). Female Pig-nosed Turtles reach maturity around 18-19 years old while male Pig-nosed Turtles reach maturity around 16-17 years old. Female turtles lay their eggs in sandy riverbanks during the late dry season in preparation for the wet season (reptilepark, 2024). When the offspring are fully developed, they remain in their eggs until conditions are stable as they require flooding to hatch or a drop in air pressure from a storm (reptilepark, 2024).

The Pig-nosed Turtle has been classed as endangered due to the wide variety of threats that has reduced this species numbers and habitat. First threat to this species in the introduction of invasive species such as the European Red Fox and Feral pigs. The European Red Fox feeds on the eggs of nesting females or eating the adults when they resting while the Feral pigs may feed on the eggs of turtles (Petrov et al, 2023). Another threat to the Pig-nosed Turtles is the wildlife trading/pet trading with both adult turtles and eggs been harvested for the pet trade, meat, and medicine (Shepherd, C. R. et al. 2020). A third threat is the consumption of turtle meat. Pig-nosed Turtles and their eggs are considered a food source for indigenous peoples in the area (IUCN, 2024). Habitat degradation and destruction is another threat to the Pig-nosed Turtle as land used by farmers can lead to sediment build up in the rivers which affects the turtle’s food supply and their access to the water (Petrov et al, 2023).

Next time, we will be covering a species of rabbit that lives in Africa and has become critically endangered from a variety of threats.

References

Eisemberg, C., van Dijk, P.P., Georges, A. & Amepou, Y. 2018. Carettochelys insculpta. The IUCN Red List of Threatened Species 2018: e.T3898A2884984. https://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T3898A2884984.en. Accessed on 01 August 2023.

Eisemberg, C. C., Rose, M., Yaru, B., Amepou, Y., & Georges, A. (2015). Salinity of the coastal nesting environment and its association with body size in the estuarine pig‐nosed turtle. Journal of Zoology., 295(1), 65–74. https://doi.org/10.1111/jzo.12179

https://www.dcceew.gov.au/environment/biodiversity/threatened/nominations/ineligible-species/carettochelys-insculpta accessed on 13/08/2024

https://www.iucnredlist.org/species/3898/2884984 Accessed on 13/08/2024

Petrov, K., Sutcliffe, S., Truscott, H., Kutay, C., Eisemberg, C.C., Spencer, R.J. et al. (2023) Turtles in trouble. Conservation ecology and priorities for Australian freshwater turtles. Austral Ecology, 48, 1603–1656. Available from: https://doi.org/10.1111/aec.13418

https://www.reptilepark.com.au/pig-nosed-turtle/ Accessed on 13/08/2024

Shepherd, C. R. et al. (2020) Illegal wildlife trade, seizures and prosecutions: A 7.5-year analysis of trade in pig-nosed turtles Carettochelys insculpta in and from Indonesia. Global ecology and conservation. [Online] 24e01249-

Picture references

All pictures from (https://www.iucnredlist.org/species/3898/2884984


Saturday, May 6, 2023

Species Profile: European Mink (Mustela lutreola)

Hello again, welcome back to animals under threat. Today, we will be covering a species of mustelid from Europe. This mustelid is currently one of the most endangered mammal species found in Europe with threats from habitat destruction and introduction of invasive species has reduced the population of this mustelid. Say hello to the European Mink (Mustela lutreola).

The European mink is a small mustelid that is found in forest areas in Eurasia near rivers and lakes due to its semi aquatic nature and is rarely found more than 100m away from freshwater sources (Maran et al, 2016). Weighing around 550-800 grams and at a length of 31.5cm for females/38cm for males, the European mink feeds on a variety of aquatic life such as crabs, fish, frogs, and salamanders. They will also feed on mice, hares, aquatic birds, and their eggs while been able to take down prey larger than themselves (globalconservation.org, 2023).


European mink historic range (red), confirmed current range (orange), possible current range (purple). Map courtesy IUCN.

Female European Minks breed in the first year on their life and have a single litter each year after the first with the number of young ranging from 3-7. Females stay close to lagoon/ rivers to provide food for their young and to protect them from predators (Mañas et al, 2016). In captive, male European Minks displayed high levels of boldness for exploration during breeding season while females became less bold (Maran et al, 2018).

Habitat destruction and the introduction of invasive species such as American Mink (Neogale vison) have negatively impacted the European Mink population since the 19th century. Destruction of the rivers and lakes for housing has destroy the mink’s potential dens and food sources as the European mink needs aquatic environments due to its semi aquatic nature (Zuberogoitia et al, 2013). The introduction of the American mink for the fur trade as led to minks escaping from cages and breeding in the wild. Competition for resources between the two species has affected the population of the European mink due to the American mink’s aggressiveness, leading to the European mink been driven from their habitats (Maran et al, 2018).

Next time, we will be covering a critically endangered species of Muridae endemic to the Northern Territory, Australia.


References

https://globalconservation.org/species-facing-extinction/european-mink/

Maran, T., Skumatov, D., Gomez, A., Põdra, M., Abramov, A.V. & Dinets, V. 2016. Mustela lutreola. The IUCN Red List of Threatened Species 2016: e.T14018A45199861. https://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T14018A45199861.en. Accessed on 06 May 2023.

Mañas, S., Gómez, A., Asensio, V., Palazón, S., Pǒdra, M., Casal, J., & Ruiz-Olmo, J. (2016). Demographic structure of three riparian mustelid species in Spain. European Journal of Wildlife Research, 62(1), 119–129. https://doi.org/10.1007/s10344-015-0982-

Maran, Tiit and others, 'European mink: restoration attempts for a species on the brink of extinction', in David W. Macdonald, Chris Newman, and Lauren A. Harrington (eds), Biology and Conservation of Musteloids (Oxford, 2017; online edn, Oxford Academic, 18 Jan. 2018), https://doi.org/10.1093/oso/9780198759805.003.0017, accessed 6 May 2023.

Zuberogoitia, I. et al. (2013) The impact of river fragmentation on the population persistence of native and alien mink: an ecological trap for the endangered European mink. Biodiversity and conservation. [Online] 22 (1), 169–186




Sunday, November 15, 2020

Species Profile: Northern Hairy-nosed Wombat

Hello again, welcome back to animals under threat. Today, we will be covering one of the three species of wombat from Australia. Belonging to the family Vombatidae (wombats), this wombat is the largest of the three species and is lesser known of the wombats. Say hello to the Northern Hairy-nosed Wombat (Lasiorhinus krefftii).

As stated in the introduction, the Northern Hairy-nosed Wombat is the largest of the wombat species that can measure up to a meter long and can weigh up to 32-40kg. They are characterized by their wide muzzle, longer/pointer ears and has softer fur than the other wombats. Despite there large size, this wombat can reach a speed of 40km/h, but only over short distances (australiangeographic.com, 2020).

Northern Hairy-nosed Wombat (gender unknown) by Tina Janssen / Safe Haven AACE.

Northern Hairy-nosed Wombat prefer savanna and open eucalypt woodlands along inland river systems as they feed on a wide variety of native/introduced grasses. They only eat the leaves instead of the stem as it provides the wombat with good nutrition. They feed for at least six hours in winter and two hours and summer compared to Eastern grey Kangaroo that must feed for 18 hours a day. This is because of their burrows have a cool, humid temperature which helps conserve the wombat’s energy. Female wombats reach sexual maturity at 2.5 years old while males take 3 years to sexually mature. Most baby wombats are born in summer and stay in their mother’s pouch for 8/9 months (environment.des.qld.gov.au, 2020).

Originally thought to be extinct in the early 20th century, a small population was found in Epping Forest National Park in Central Queensland. Currently the population size is estimated around 160-200 individuals (theconversation.com, 2020). Classed as critically endangered by the IUCN, the major threats to the wombat are agricultural development, droughts, invasive species, and fire/fire suppression. Agricultural development for livestock destroys the grass the wombat feeds on and decreases the available land for wombats to burrow. Droughts and fire management also destroys the grasses the wombat feeds on and affect the availability on water the wombat can access. Invasive species destroy/remove wombats from their burrows and attack wombats that is leading to increase risk in inbreeding due to lack of genetic diversity (Taggart et al, 2016).


Next time, we will be covering a species of mustelid from Europe.References



Monday, June 29, 2020

Species Profile: Cross River Gorilla


Hello again, welcome back to animals under threat. Today, we will be covering a subspecies of Western Gorilla that is found near the Cross River in Nigeria. This subspecies was once considered to be extinct in the wild until scientists found a small population in 1980’s. Classed by the IUCN as Critically endangered and is one of Africa’s most endangered species. Say hello to the Cross River Gorilla (Gorilla gorilla spp. diehli).

This subspecies looks similar to the Western lowland Gorilla with the only differences in the skull size and tooth dimensions (Bergl et al, 2016). Cross River Gorillas prefer dense forest habitat but can live in riparian forests and high altitude grasslands. Their diet depends on which habitat they reside in as they prefer fruit during periods of seasonal abundance and herbs and bark through out the rest of the year (Etiendem & Tagg, 2013).

Photo of Cross River Gorilla eating by Nicky Lankester, Limbe Wildlife Centre (above) and Male gorilla by Wildlife Conservation Society (below).
 

Cross River Gorilla are one of the lesser known species as current studies estimated that there are 200-300 individuals left in the wild with estimated number of individuals in a group to be around 11 by examining nests left by the Gorillas (Funwi-Gabga et al, 2012). Each group is led by a male and the females and his young make up the rest of the group. Lead male Gorillas are sometimes called “silverbacks” due to the silver colour on their back (Worldwildlife.org, 2020).

Poaching, habitat destruction, climate change and inbreeding are some of the major threats to the Cross River Gorilla survival. Gorillas are sometimes caught in snares set by poachers to catch other animal species. The trapped Gorilla struggles to escape the snare this can result in injury or death. Habitat destruction of their major food sources for agricultural reasons has led to conflict between humans and Gorillas and with increasing climate change has force the Cross River Gorilla to move to other areas where they may be unable to survive in. Due to the small population, inbreeding is a big risk as lack of genetic flow between groups and lead to deformities in future generations and higher risk of diseases due to poor immune systems (Bergl et al, 2016).

Next time, we will be covering a species of wombat from Australia.

References

Bergl, R.A., Dunn, A., Fowler, A., Imong, I., Ndeloh, D., Nicholas, A. & Oates, J.F. 2016. Gorilla gorilla ssp. diehli (errata version published in 2016). The IUCN Red List of Threatened Species 2016: e.T39998A102326240.

Etiendem, D.N. & Tagg, N. 2013, "Feeding Ecology of Cross River Gorillas (Gorilla gorilla diehli) at Mawambi Hills: The Influence of Resource Seasonality", International Journal of Primatology, vol. 34, no. 6, pp. 1261-1280.

Funwi-Gabga, N., Funwi-Gabga, N., Mateu, J. & Mateu, J. 2012, "Understanding the nesting spatial behaviour of gorillas in the Kagwene Sanctuary, Cameroon", Stochastic Environmental Research and Risk Assessment, vol. 26, no. 6, pp. 793-811.

https://www.worldwildlife.org/species/cross-river-gorilla retrieved 28/6/2020


Picture references
https://www.iucnredlist.org/species/39998/102326240

Thursday, March 26, 2020

Species Profile: Trumpeter Swan


Hello again, welcome back to animals under threat. Today, we will be covering a species of bird from the genus Cygnus that was at the brink of extinction but is making a comeback. It is also called North America’s heaviest flying bird with males weighing over 26 pounds and the main character in E. B. White’s 1970 children’s book the Trumpet of the swan. Give a warm welcome to the trumpeter swan (Cygnus buccinator).

The Trumpeter swan is one of three species of swans that resides in North America along with the Mute swan (Cygnus olor) which was introduced and the Tundra Swan (Cygnus columbianus). Trumpeter and tundra swans look similar to each other, but Trumpeter swans are characterized by their solid black straight beak and white feathers while Tundra swans have yellow markings under their eyes (ebird.org, 2020). Male Swans are called the Cob and usually weigh more and are larger than female swans which are called the Pen (trumpeterswansociety.org, 2020).
Trumpeter Swans by Jakub Fryš

Trumpeter Swans prefer to live in areas that are shallow freshwater lakes with lots of aquatic vegetation to feed on. They also need large areas of open water in order to do their running-take-off. Female Trumpeter swans also need lake areas with small islands or beaver dams of nesting (allaboutbirds.org, 2020). Weighing over 26 pounds and 1.8 long in length, the Trumpeter swans gather at the end of lakes/rivers in order to start their take off run. During their take off run, the swan will flap its 3m wingspan in order to take off from the water (Britannica.com, 2018).

Video by Lisbasan

Adult Trumpeter swans mainly feed on aquatic vegetation while they are swimming, terrestrial grasses and agricultural grains when on land. Young juvenile swans however feed on insects, small fish and fish eggs and small crustaceans before changing to a plant-based diet in the first few months. Adults and juveniles will up-end or dabbling in order to reach food that is underwater which makes them look like they are upside down and adults will dig into muddy substrates to reach roots and tubers (Johnson & Lockwood, 2013).

swan feeding by Rodger Beardmore (above) and silly swans by Kayo Roy (below)

Trumpeter swans build their nests on a site that is surrounded by water and is 600m from the shore. The nest is usually built on top of a beaver/muskrat dam and dens with both parents collecting plant that usually consist of aquatic vegetation to build the nest (Wells & Wells, 2007). The female uses her body and bill to shape the nest on top of an aquatic vegetation mound. The female will lay a clutch of eggs that can range between 4-6, are a creamy white colour and are incubated for 32-37 days. Young swans are called cygnets and are covered in grey colour down and can leave the nest after 24 hours to swim and feed. Adult swans usually mate for life although there have been cases where if one dies, the other will sometimes take another mate (ebird, 2020).
juvenile by Greg Hume

This species was once driven close to extinction by poaching, habitat destruction and lead poisoning. Trumpeter swans were poached for their feathers which were popular for designing, meat for eating and game and skin for powder puffs (Johnson and Lockwood, 2013). Destruction of wetlands that the swans need for feeding and nesting has affected the swan’s population as they cannot survive without it. Lead poisoning from discarded lead shots also affected the population as young swans fed on the shots which led to lead poisoning and death of young swans (Wells & Wells, 2007).

Next time, we will be covering a subspecies of Western Gorilla and is found near the Cross River, Nigeria.

References (retrieved 27/03/2020)
https://www.allaboutbirds.org/guide/Trumpeter_Swan/overview
https://www.britannica.com/animal/swan published 2018
https://ebird.org/species/truswa

Johnson, WP, & Lockwood, MW 2013, Texas Waterfowl, Texas A&M University Press, College Station. Available from: ProQuest Ebook Central. [26 March 2020].

Wells, JV, & Wells, JVV 2007, Birder's Conservation Handbook : 100 North American Birds at Risk, Princeton University Press, Princeton. Available from: ProQuest Ebook Central. [26 March 2020].

https://www.trumpeterswansociety.org/swan-information/identification/overview.html retrieved 27/03/2020

Picture references
https://en.wikipedia.org/wiki/Trumpeter_swan (Trumpeter Swans by Jakub Fryš)
https://search.macaulaylibrary.org/catalog?taxonCode=truswa&q=Trumpeter%20Swan%20-%20Cygnus%20buccinator (swan feeding by Rodger Beardmore)
https://search.macaulaylibrary.org/catalog?taxonCode=truswa&q=Trumpeter%20Swan%20-%20Cygnus%20buccinator (silly swans by Kayo Roy)

https://en.wikipedia.org/wiki/Trumpeter_swan (juvenile by Greg Hume)

Wednesday, March 25, 2020

Species Profile: Maned Wolf


Hello again, welcome back to animals under threat. Today, we will be covering an animal that looks like a giant fox that lives in South America and has the nickname “fox on stilts”. It is the only known species in the genus Chrysocyon and belongs to the Canidae family. Please give a warm welcome to the Maned Wolf (Chrysocyon brachyurus).

The Maned wolf is a largest canid that resides in Central and Eastern South America. It is characterized by its red fur similar to the red fox and stands on end giving the appearance of a mane. Black markings on its long legs, muzzle and the tips of the mane. It also has a white bib underneath its muzzle and on the tip of its tail (nationalzoo.si.edu, 2020). Its preferred habitat are grasslands, swamps, scrub forest, woodlands with open canopy and mixed forest. Maned wolfs can reach a height of 1m and can weigh over 20-25kgs (wwf.panda.org, 2020).
Chrysocyon brachyurus by Edu Fortes

The Maned wolf is an omnivore which means its diet is both meat and vegetation material. It feeds on small mammals, birds and fish, but majority of its diet is plant martial that includes sugar cane, tubers, and fruit. The most common plant found in Maned wolf fecal matter is the Solanum lycocarpum or Wolf Apple (Aragona & Setz, 2001). A graph from the article “feeding habits of the Maned wolf, Chrysocyon brachyurus (Carnivora: Canidae), in southeast Brazil" shows that during the dry season, Maned wolves mostly fed on small mammals and the wolf apple. During wet season, the diet changes to fruits that are more plentiful during that season (de Arruda Bueno & Motta-Junior, 2009).

Wolf fruit By João Medeiros (above) and graph by de Arruda Bueno, A. & Motta-Junior, J.C. 2009 (below)

Maned wolves are mostly solitary animals unlike most wolf species and only get together when it is breeding season. They use urine to mark their territory, hunting paths or where they buried prey. Mating season for Maned wolves is between November to April and gestation can last up to 60 days. A female Maned wolf can have up to 2-6 pups in a litter and the pups have dark black fur compared to their parents. After 3 weeks, the pups fur begins to turn red and follow their mother while she forges for food. Both parents do care for the pups, but the female does most of the work, up to one year where they are fully matured and leave the parent territory to find their own (Mannise et al, 2017).

(wolf pup 1) by Michael stone (above) and (wolf pup 2) by Trisha M Shears

The Maned wolf is classed by the IUCN red list as near threatened as there are currently four major threats to this species. The first threat is habitat loss/alteration for crops has affected the wolfs food supply as a majority of the wolfs diet is vegetation. Human persecution is the second threat as the Maned wolf is blamed for the attacks on livestock and are killed in retaliation. The third threat is vehicular collision as increasing traffic on highways has led increase in fatality in Maned wolfs crossing the roads. The final threat is pathogens introduced by domestic animals. Pathogens such as canine distemper virus and canine adenovirus can affect both pups and adults leading to fatalities (Paula & DeMatteo, 2015).

Next time, we will be covering a species of bird from the genus Cygnus that was at the brink of extinction but is making a comeback.

References
Aragona, M. & Setz, E.Z.F. 2001, "Diet of the maned wolf, Chrysocyon brachyurus (Mammalia: Canidae), during wet and dry seasons at Ibitipoca State Park, Brazil", Journal of Zoology, vol. 254, no. 1, pp. 131-136

de Arruda Bueno, A. & Motta-Junior, J.C. 2009, "Feeding habits of the maned wolf, Chrysocyon brachyurus (Carnivora: Canidae), in southeast Brazil", Studies on Neotropical Fauna and Environment, vol. 44, no. 2, pp. 67-75.

https://nationalzoo.si.edu/animals/maned-wolf retrieved 25/03/2020

Mannise, N., Cosse, M., González, S., Emmons, L.H., Duarte, J.M.B., Beccaceci, M.D. & Maldonado, J.E. 2017, "Maned wolves retain moderate levels of genetic diversity and gene flow despite drastic habitat fragmentation", Endangered Species Research, vol. 34, pp. 449-462.

Paula, R.C. & DeMatteo, K. 2015. Chrysocyon brachyurus (errata version published in 2016). The IUCN Red List of Threatened Species 2015: e.T4819A88135664

https://wwf.panda.org/our_work/wildlife/profiles/mammals/wolf_maned/ retrieved 25/03/202

picture references
https://www.iucnredlist.org/species/4819/88135664 (maned wolf 1 Edu Fortes)
https://en.wikipedia.org/wiki/Maned_wolf Wolf fruit By João Medeiros

de Arruda Bueno, A. & Motta-Junior, J.C. 2009, "Feeding habits of the maned wolf, Chrysocyon brachyurus (Carnivora: Canidae), in southeast Brazil", Studies on Neotropical Fauna and Environment, vol. 44, no. 2, pp. 67-75. (graph)

https://en.wikipedia.org/wiki/Maned_wolf (wolf pup 1) by Michael stone
https://en.wikipedia.org/wiki/Maned_wolf (wolf pup 2) by Trisha M Shears

Saturday, March 21, 2020

Species Profile: Green Sea Turtle


Hello again, welcome back to animals under threat. Today, we will be covering a species of sea turtle that got its name by the colour of fat underneath its carapace/shell. This species is well documented as studies are been continuing to help prevent the species from going extinct. Please give a warm welcome to the Green sea turtle (Chelonia mydas).

As stated above, Green sea turtles get their name from the colour of fat underneath its carapace/shell. This turtle is the one of largest sea turtles and is the only one of its species in the genus Chelonia. It is also the only sea turtle that feed on vegetation (Worldwildlife.org, 2020). Green sea turtle has a unique feature that distinguishes them from other species of sea turtles. This feature is a single pair of prefrontal scales (scales in front of its eyes) instead of two pairs which other sea turtles have. The carapace of the Green sea turtle is bony, has large non-overlapping scales and the body is almost oval shaped. The flippers each have one claw and the carapace colour varies from white, yellow, green and brown with radiating stripes (conserveturtles.org, 2020).
turtle swimming by Brocken Inaglory

Green sea turtles can weigh up to 700 pounds and can measure up to 5 feet. Males are slightly larger than females and have a longer tail. Adult turtles feed primarily on sea grass/algae while juvenile sea turtles feed on invertebrates such as crabs, jellyfish and sponges (nationalgeographic.com, 2020). 
sea turtle eating by P.Lindgren

Green sea turtle become sexually mature between 25 to 40 years old and breeding occurs between late spring to early summer. Males can mate every year, but females have to migrate every 2-5 years from foraging areas to nest. Females will lay over 100 eggs per nest before leaving the nesting area to return back to their foraging areas (fisheries.noaa.gov, 2020).
mother turtle nesting (above) by Nicolas Pilcher and baby turtle (below) by Kathryn Pintus

After 2 months, the young turtles hatch and make their way out of nest to the open ocean. They follow the brightest horizon to find the sea, but artificial light from houses/cities can confuses the turtles causing them to follow the artificial light instead of heading to the ocean. Young turtles are also preyed on by predators, however due to the large number of young turtles hatching and fleeing to the ocean, some of the turtles reach the ocean (Hannah et al, 2013).

Baby turtles 2 (above) by Nicolas Pilcher and baby turtle 3 swimming (below) by Dr Oguz Turkozan

Unfortunately, the Green sea turtle has reached endangered status due to pollution, hunting, coastal development and mortality by fishing nests. Young sea turtles mistake plastic bags as jellyfish causing them to choke and block the digestive track causing the turtle to die. Hunting turtles for their meat, shell and eggs has caused the population to decrease although efforts have been made to stop this. Coastal development of beaches has destroyed nesting sites and nests that have been established there. Green sea turtle can hold its breath for a long time but when entangled in nets, the turtles thrash around becoming stress and use more oxygen causing them to drown.
(caught turtles) by unknown

Next time, we will be covering an animal that looks like a giant fox that lives in South America.

References
https://conserveturtles.org/information-sea-turtles-green-sea-turtle/ retrieved 22/03/2020
https://www.fisheries.noaa.gov/species/green-turtle retrieved 22/03/2020

Hannah B. Vander Zanden, Arthur, K.E., Bolten, A.B., Popp, B.N., Lagueux, C.J., Harrison, E., Campbell, C.L. & Bjorndal, K.A. 2013, "Trophic ecology of a green turtle breeding population", Marine Ecology Progress Series, vol. 476, pp. 237-249.

https://www.nationalgeographic.com/animals/reptiles/g/green-sea-turtle/ retrieved 22/03/2020
https://www.iucnredlist.org/species/4615/11037468 retrieved 22/03/2020
https://www.worldwildlife.org/species/green-turtle retrieved 22/03/2020

Picture references
https://www.iucnredlist.org/species/4615/11037468 (baby turtle 2 by Nicolas Pilcher)
https://www.iucnredlist.org/species/4615/11037468  (mother turtle by Nicolas Pilcher)
https://www.iucnredlist.org/species/4615/11037468 (baby turtle 1 by Kathryn Pintus)
https://www.iucnredlist.org/species/4615/11037468 (baby turtle 3 by Dr Oguz Turkozan)
https://en.wikipedia.org/wiki/Green_sea_turtle (swimming sea turtle) By Brocken Inaglory
https://en.wikipedia.org/wiki/Green_sea_turtle  (sea turtle eating) By P.Lindgren
https://en.wikipedia.org/wiki/Green_sea_turtle (caught turtles) by unknown