Macrochelys Temminckii Alligator Snapping Turtle Biology Essay

Published: November 2, 2015 Words: 1332

It is found in lake, ponds and river which are freshwater. The distribution is in south of Canada, north of United State, South Carolina and north of Florida. They are also found in the Missouri River at far north as the Gavins Piint Dam at Yankton, South Dakota.

The IUCN has list this turtle as a threatened species. It had been subjected to international protection and listed under CITIES III which will limit its exportation in the United State

The major reason to this is the loss of its habitat and hunting of the turtles. The habitat of the turtles is lost due to water pollution and use up of land by the increasing human population. The turtles have been hunted for their valuable carapaces. They are also made into soup which is considered by any to be a delicacy.

Physical Adaptations to their Habitat

Adults of Macrochelys temminckii have strong base tails which is long and thick, capable of attacking predators that harm them thus resulting in the absence of nature predator except human.

Macrochelys temminckii rely on their strong jaws for defence and create a hard bite in defence if disturbed.

Their sturdy carapaces protect them from any directed force or harm.

They are also camouflaged to increase chances of survival in their habitat.

In their camouflaged mouth, they have vermiform appendage on the tip of their tongue to lure fish

Miscellaneous characteristics/habitats/unique facts

Macrochelys temminckii are the largest freshwater turtles.

The turtles are also called "dinosaurs" in the turtle world due to its primitive looks.

They can weigh over 175lbs with an average adult size of 2 feet long. Male turtles are normally larger than female turtles.

The young of Macrochelys temminckii are usually brown in colour with rough shells and long tails whereas adults are of a solid gray, brown, black or olive-green shade and often covered with algae to keep the turtle camouflaged.

For camouflaging purpose, they also have bright yellow patterns around the eyes to break the outline of the eye.

Macrochelys temminckii has an average speed of 0.42mph.

They spend most of their time in water, except for the females which are nesting on the land. They remain motionless in the water. With algae, they are almost unnoticeable by fishes.

To capture their prey, it utilises their sharp and powerful jaws or tips to tear their prey apart. The turtle possess a vermiform on their mouths. They lie motionlessly in the water with their mouths wide open and they would wriggle their tongues similar to a worm's movement to attract fishes.

They have large, heavy head and long, thick tail with dorsal ridges of large scales. Their carapaces have three keels along it with extra scutes along the side.

About 2 months after the early spring, the females will dig the nest at least 50 yards from water to prevent flood and lay about 9 to 25 eggs. The sex of babies is dependent on the temperature at which eggs are hatch. It takes about 100 to 140 days to hatch. Their life expectancy can be about 150 years.

Scientific Name : Geochelone nigra abingdoni

Common Name : Lonesome George

Distribution of species: Pinta Island, Galápagos Archipelago

Wildlife Conservation Status

The Galapagos tortoises are listed on Appendix I of CITES. They are classified as Vulnerable (VU) whereas Geochelone nigra abingdoni is listed as Extinct in the Wild (EW) on the 2010 IUCN Red List of Threatened Species.

Threats to Population

Galapagos tortoises are main sources of valuable fresh meat and dilute urine as drinking water for the sailors. More of the population were hunted for high grade "turtle oil". People from the early settlement of the island hunted them for food and cleared their habitats for agricultural use. Mammal species introduced feed on their eggs and young whilst cattle and donkeys reared undergo interspecies competition with them for grass as food.

Physical Adaptations to their Habitat

Long necks and notch in their shell allow Galapagos tortoises to reach for the foliage on cactus plants grown as food source for survival and fast growth rate.

Carapace (large shell) made of bone with bone plates integral to the skeleton and fused with the ribs presents a strong protective shield to a would-be predator.

Large scales on their legs increases protection as they meet their elbows front when withdrawing to protect their head.

Pillar-like legs are structured to support their weight and facilitate movement.

Scaly skin on exposed legs and head also acts as armour to prevent damage due to movement around their habitat.

Miscellaneous characteristics/habitats/unique facts

Fully grown adult can weigh over 300lbs and reach length up to 4 feet long.

Their life expectancy is about 150 years.

Galapagos tortoises are herbivorous with a diet of fresh young grass, prickly pear cactus, leaves, vines and fruits. The dew and sap in vegetation provides them moisture, especially Opuntia cactus.

Galapagos tortoises can survive for a year without food or water. They are able to hydrolyse their body fats to produce water.

In smaller and drier islands such as Espanola and Pinta, Galapagos tortoises in these places tend to have "saddleback" shells which are flatter than "domeback" shells, elevated above the neck and flared above the hind feet. With longer neck and limbs, they are able to reach for taller vegetation. Moreover, they are smaller and require less food.

Galapagos tortoises are slow-moving with an average speed of 0.18mph.

At sunrise, the tortoises readily bask for two hours, absorbing the energy before becoming active again, wallowing in water or mud for approximately eight hours daily. These are thermoregulatory responses and protections from parasites (mosquitoes & ticks).

They are believed to be deaf due to their lack of reactions towards sounds from near.

Mating occurs at any time of the year with seasonal peaks. Head-biting occurs during competition for the female and usually tortoise with longer neck wins.

The female digs nests in areas with dry, sandy ground and makes a muddy plug out of urine and leaves to incubate the eggs. In rocky areas, the eggs are randomly laid into cracks. Temperature of incubation of eggs determines sex of babies and it takes 100 to 200 days for them to hatch.

Galapagos tortoise exhibits mutualism with finch. The finch picks ticks hidden in the folds of the skin on the tortoise's stretched neck, freeing the tortoise from harmful parasites and providing itself an easy meal.

Specific name

Macrochelys temminckii

Geochelone nigra abingdoni

Common name

Alligator Snapping Turtle

Lonesome George

Wild Conservation Status

Vulnerable

Extinct in Wild

Threats to Population

Loss of habitat due to water pollution

Hunted for carapaces and meat

Hunted as food source and for turtle oil

Interspecies competition

Characteristics

Weight

175 lbs

300 lbs

Size (length)

2 feet

4 feet

Life expectancy

150 years

150 years

Average Speed

0.42 mph

0.18 mph

Classification (eating habits)

Omnivorous

Herbivorous

Physical Characteristics

Sharp-edged mouth

Three keels and extra scutes along carapaces

Smooth-edged mouth

Flatter "saddleback" shells, elevated above neck and flared above hind feet.

Adaptations

Defence system

Strong base tail for attacking

Strong jaws for hard bite

Sturdy carapaces as shield

Camouflaged

Sturdy carapaces as shield

Scaly skin on legs and head as armour

Feeding Adaptations

Sharp-edged jaws enhance grasp of objects

Camouflaged mouth and vermiform appendage on tip of tongue to lure fish

Long neck and notch in shells allows stretching for foliage

Able to hydrolyse their body fast for water if starved

Habits

Daily habits

Rarely bask

Remain motionless in water for most of the day

Bask after dawn for 2 hours

Wallow in mud or water for most of the day

Nesting

Nests dug at least 50 yards from water to prevent flood

9 to 25 eggs laid each time

Time taken for hatching is 100 to 140 days.

Nests dug in dry area are made of muddy plugs whereas in rocky areas, eggs are randomly laid into cracks

2 to 16 eggs laid each time

Time taken for hatching is 100 to 200 days.

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