Rhinoceros sondaicus
The Javan rhino is one of the rarest mammals left on planet earth. They are critically endangered, and continue to lose population density every passing year.
Introduction
By spreading information about this fantastic subspecies of rhino, we may be able to increase awareness, and help fund rhino conservation societies. Many of these rhino societies specifically target this subspecies, and one of the only places this breed is still found, are a few far flung reservations built specifically for these creatures. Here is some information about this fantastic mammal, and how it lives daily.
Description
The javan rhino is deep brown in coloration, so deeply colored, that they often look black when wet or muddy. Like most other rhinos, the folds of their skin are a dark pink. They have two folds of skin at the nape of the neck that appears almost scaley in texture. They are very similar to the great horned rhino, and one was even mistakenly displayed as such in a zoo.
Javan rhinos are slightly smaller than their great cousins, weighing about two-thousand kilograms, and standing a little less than two meters tall at shoulder height. The few that still occupy Vietnam are much smaller, weighing as little as eight-hundred kilograms, and standing just a little over one meter. It is presently unknown why these rhinos are so much smaller.
The javan’s horn is a dark grey color, and can be quite massive. The largest recorded javan horn was measured at twenty-seven centimeters long. Females have no horn, or a small knob at the end of the snout. The horn, while very dense and hard, is not used for combat, rather it is a tool for tear branches and shaking loose vegetation. This powerful tool allows them to pull whole trees down on some occasions.
Males and females of the javan subspecies are of similar size, though the females can sometimes be slightly larger. Both sexes have longer noses and lips than most subspecies of rhino.
Distribution
The javan rhino can only be found in national parks in modern times. Poaching and slow reproductive cycles have made them dangerously dependent on their human protectors. The largest population can be found in Ujung Kulon national park, where about fourty of these creatures reside. Another, smaller population of seven to fifteen resides in Cat Tien national park in Vietnam. Both of these national parks are still under heavy ecological pressure, and the population has only continued to decrease in recent years.
It is speculated that they once made the surrounding low, wetlands as shelter, but they were forced to retreat into the less lush highlands due to deforestation and poaching.
Behavior
The javan rhino, like many other subspecies, is a solitary creature, with the exception of females who are weaning young. However, they do come together in larger groups during mating season, ostensibly to choose a suitable mate. They also sometimes come together in larger groups around well-known mud wallows, or salt licks, both of which are necessary for the rhinos comfort and survival. They also may come together to leave large collective dung piles.
Males hold large territories, marking them with broken foliage, urine, feces, and by scraping the ground in a delineating manor. These territories often overlap, though rhinos do not seem to fight each other for control of these territories. They may also twist saplings to show their strength and territorial rights.
Javans are also much less vocal than many of their genetic cousins, preferring to communicate with odors and scraping than whistles and grunts. They may once have been a more gregarious species, but fear of humans has led this species of rhino to attack people who approach slowly, and run from those who act more quickly. This has made the javan rhino a very difficult creature to study, so not much more is known about their behavior.
Feeding
Javan rhinos are browse eaters, meaning they pick through a varied array of plant life to find the most nutritional bits. They most commonly ingest fallen foliage, such as tree matter, fruits, and occasionally budding saplings. Most of their favorite plant life grows in forest clearings, where trees have fallen over to create pocket glades. The javan rhino usually ingests about fifty kilograms of plant matter daily, but can store more fat than most other subspecies, so they are known to eat much more than that occasionally.
The javan’s upper lip is prehensile, meaning it can grab and manipulate certain objects. This allows it to pull saplings and smaller trees over to get at the crown leaves at the top of the tree or fruits. The javan rhino chews with a row of specialized molars, designed to mash thicker vegetation. These teeth often become worn and make it difficult for the javan rhino to digest its food properly. Most javan rhinos in the wild die due to malnutrition associated with this dental degradation. Javan rhinos digest their food in a large colon, and with microorganisms in their low intestines. Salt licks are important in the production of these microorganisms and refreshing minerals in the blood.
Reproduction
Unfortunately, due to their solitary nature, and natural fear of humans, not much is known about the javan rhinos’ reproductive habits. Females usually reach sexual maturity at about four years of age, males at about six years. Gestation take approximately sixteen months, and the weaning period is about two years. A javan rhino will only give birth about once every five years. Most javans live about thirty-five years in the wild.
The exact mating habits, and the cycles that they mate on, are presently unknown. This makes breeding conservation very difficult for humans to oversee. What is known is that rhinos are delivered as most mammals, with live birth, but only one will be born at a time.
