Description

Largest terrestrial arthropod and invertebrate in the world

Type of hermit crab

Can reach length of 16 in and weight of 9 lb

Leg span can reach size of 3 ft

Carapace or upper section of exoskeleton can reach length of 3.1 and width of 7.9 in

Males generally larger than females

Can live up to 60 years in the wild

Come in a range of colors from orangish-red to purplish-blue

Most common color is blue

Body is like most decapods and is split into a front section or thorax and an abdomen

Covered in a thick and tough exoskeleton created by layering chitin and chalk

Their thorax contains their 10 legs

First two are the large claws they use to rip things apart and left one is larger

Next four are large walking legs with pointed ends

Help them climb trees and overhanging surfaces

Fourth pair is smaller with small, tweezer like claws

Young coconut crabs use them to hold onto shells or coconut husks for protection

Last pair is usually hidden away in the cavity that holds their “lungs”

Used by females to hold their eggs and by males for mating

Keep their tail curled underneath them for protection

Their breathing apparatus is housed in a cavity inside the thorax

Known as branchiostegal lungs

They are considered a developmental stage between gills and lungs

Contains tissue that is similar to gills

Instead of filtering oxygen from water, filters from the air

Located here to decrease distance for blood/gas diffusion and return to the heart

Require water to function properly so coconut crab uses last pair of leg to keep them moist and clean

They do have gills but they are very small

Habitat

Found in areas with coconut palms

Generally follow the distribution of the coconut palm

Includes many islands across the Indian and Pacific oceans

Also lives on the coast of Africa near Zanzibar

Largest population lives on Christmas Island

Northern and Southern limits are the Tropic of Cancer and Tropic of Capricorn

Western limit is Zanzibar

Eastern limit is Gambier Islands

Behavior

Coconut crabs usually come out during the evening and night to escape the heat

Also come out while it’s raining or moist since they can keep their lungs moist

Which means they can breathe better

During the day, they hide in their burrows to conserve water

While resting, they close the entrance to their burrow with one of their claws

This traps in the moisture they need to keep their “lungs” moist

Coconut crabs are omnivores

Typically eat fruits, nuts, drupes, seeds and pith of fallen trees

Also eat coconuts

If there is husk on it still, the crab will peel off the husk until the three germination pores are visible

It will then bang its pincers on the coconut until it busts open

The crab then consumes the flesh of the coconut

Very good climbers so can reach food in trees very easily

Will also eat organic matter

They are also really good hunters

Typically hunt rats, other coconut crabs, and even large sea birds

Live in burrows or rock crevices depending on the terrain around them

Dig burrows in sand or loose soil

Line burrow with fibers from coconut husk

Also hide in burrows when they go through their annual molt or shedding of old exoskeleton

Since they need time for their new exoskeleton to harden, they may spend 3-16 weeks in the burrow

Only predators are humans and other coconut crabs

Generally safe to eat but may become poisonous depending on what they eat

Mating occurs frequently between May and September

After mating, the female will lay her eggs and glue them to the bottom of her abdomen

She will carry these eggs around for several months until they are ready to hatch

When it is time to hatch, the female will go to the shore and release the larvae into the ocean at high tide

The larvae will then spend time in the pelagic zone with other plankton for 3-4 weeks

Many of them will be eaten at this stage

They will then pass through 3-5 stages of growth before reaching the glaucothoe stage

This takes 25-33 days

At this point, the young crabs will settle to the bottom and pick a perfectly sized shell

They will then join other hermit crabs on the shoreline and make short journeys onto dry land

During this time, they keep growing and have to keep switching to better fitting shells

Eventually they will outgrow their shells and form a touch exoskeleton

Finally they leave the ocean after developing their lungs and never go back

Fun Facts

Coconut crabs cannot swim due to their lungs being designed to gather oxygen from the air

Coconut crabs have a really great sense of smell

When full grown, their claws could generate a force of 3,300 newtons

This is a lot of pressure

Can also lift up to 30 kgs which is the weight of a 10 year old

Can survive a fall of 15 ft

Description

Large even-toed ungulate and largest living camel

Can reach an overall height of 7.5-8.2 ft with a shoulder height of 5.2-5.9 ft

Can reach a head-and-shoulder length of 7.38-11.48 ft with a tail length of 14-22 inches

Can weigh between 1300-2200 lbs with the males being larger and heavier than the females

They can live up to 50 years in the wild but the average is about 30

It’s long, wooly coat comes in a wide range of colors, from dark brown to beige which they usually shed during the summer so they don’t get too warm

Wild bactrian camels are a lot smaller and slender than the domesticated ones

They have a typical camel looking face that is triangular in shape with a split upper lip

Their eyelashes are very long to protect their eyes from dust and sand as well as a nictitating membrane to wash any dust and sand out of their eyes if any gets in

They also have sealable nostrils to keep sand out of their nose when traveling through the desert

Their most distinguishing feature is the two humps on their back compared to the dromedary camel which only has one

These humps are comprised of fat which the camel stores and can live off of if there is nothing to eat

If the camel uses these fat stores, the humps begin to fall over

Their feet consist of two broad toes with very tough and flat soles so they can travel through the desert and the other habitats they live in

Habitat

These camels are migratory and inhabit many different biomes.

These include the mountains, desert, and steppes of Central Asia

Also can be found near sources of water

Their range includes most of Central Asia, from Afghanistan to China as well as Mongolia

Wild bactrian camels have a more limited range and are only found in the Gobi Desert

Behavior

Bactrian camels are diurnal and forage during the day

They are well suited for desert living with tough mouths and the ability to go without water for months

They are primarily herbivorous and will eat almost every type of plant

If plants aren’t available, they will feed on carcasses and chew on the bones, skin, and other flesh

If nothing else is available, they will eat any material they can find including rope and tents

Speaking of water, they can go without it for months as stated before but they still need to drink

When they do drink water, they can drink up to 35 gallons at once

They are also able to save water by not sweating as much and having very concentrated urine

Bactrian camels typically travel in groups of 6-20 individuals consisting of several females, their calves, and sub-adults led by a dominant male

They get along well with each other for the most part and when two groups cross paths, they may join together to create a supergroup which could reach the size of 500 camels

Once young males reach breeding age, the dominant male will chase them away and force them to join a bachelor group

When a male challenger approaches, the dominant male and the intruder will perform displays to scare off each other

If the dominant male can’t scare off the intruder, he will resort to fighting which includes biting and other attacks

Breeding season occurs year round

The gestation usually lasts for 13 months after which point, the female gives birth to one or two calves every other year

The calves are able to stand and run minutes after birth

They then nurse for about 1.5 years and stay with their moms until they reach breeding age

At this point, the males get chased off and the females may join another group or will stick around to help raise the next calf

Fun Facts

Named after a region called Bactria which was a region of ancient Central Asia from about 2500/2000 BCE-900/1000 CE

Aristotle was the first European to describe camels when he described them in his book, History of Animals, published in 4 BC

Used in caravans along the Silk Road and used by humans for thousands of years

One of a few animals to regularly eat snow as a source of water

Can survive in temperatures ranging from 122 degrees to -20 degrees

The U.S. imported bactrian and dromedary camels several times during the mid- to late-1800s because the military and others were looking for sturdier and hardier pack animals than mules and horses.

The Army even created a unit called the United States Camel Corps to see if the camels would be good pack animals in the Southwestern United States

They actually worked well for that purpose but the Civil War ended the experiment and so the camels were auctioned off or released

This lead to a group of feral camels existing for a while in the Southwest

Jefferson Davis put this experiment in motion when he was the War Secretary of the United States before leaving to be the president of the Confederacy a.k.a the Confederate States of America

Once he left, nobody else supported this experiment and it would have taken too long to train the soldiers how to use the camels, so they just continued using horses and mules

One of these escaped camels was the subject of the legend of the Red Ghost

The legend started in 1883 when ranchers went to go check on some cattle

One of their wives heard the dogs barking and rushed to the window where she saw a large, reddish colored camel carrying a skeleton on its back

She locked the door and stayed inside until the ranchers came back and heard her tale and also discovered the other wife had been trampled to death

The ranchers followed the footprints to a bush that had red hair in it

Reports of the Red Ghost continued to pop up for months and years afterwards with stories describing it as 30 ft tall and hunting and eating a grizzly bear as well as disappearing into thin air when pursued

A cowboy tried to lasso it and was almost trampled but not before seeing that it was a skeleton on the back

A group of 5 tried to shoot it but missed and knocked the head of the skeleton which still had hair and skin on it

Eventually, in 1893, a farmer named Mazoo Hastings discovered it grazing in his yard and killed it with a single shot where it was confirmed to be a camel.

A statue was erected in Quartzite, Arizona nearby to the grave of one of the camel drivers named Hi Jolly

Sources

https://en.wikipedia.org/wiki/Bactrian_camel

https://denverzoo.org/animals/bactrian-camel/

https://animaldiversity.org/accounts/Camelus_bactrianus/

http://www.ultimateungulate.com/artiodactyla/camelus_bactrianus.html