Reptiles
Reptiles are a group of animals that have scales, breathe air, and lay eggs. They include lizards, snakes, turtles, crocodiles, and more. Reptiles are found all over the world, and they have adapted to many different environments and lifestyles. Some of the most fascinating and mysterious reptiles are: Komodo dragon, Gharial, Flying snake, Tuatara.
Komodo Dragon: An Overview
The Komodo dragon, also
known as the Komodo monitor, is a species of lizard found in the Indonesian
islands of Komodo, Rinca, Flores, and Gili Motang. It is the largest
extant species of lizard, growing to a maximum length of 3
meters (9.8 ft), and weighing up to 70 kg (150 lb).Komodo
dragons have long, flat heads with rounded snouts, scaly skin,
bowed legs, and huge, muscular tails.
Habitat
These creatures have
thrived in the harsh climate of Indonesia’s Lesser Sunda Islands for millions
of years. They are found across the islands, preferring the islands’ tropical
forests. Despite their ability to walk up to seven miles per day, they tend to
stay close to home, rarely venturing far from the valleys where they hatched.
Reproduction
Once a year, when they’re
ready to mate, female Komodo dragons emit a scent in their feces for males to
follow. When a male locates a female, he scratches her back and licks her body.
If she reciprocates the licking, they mate. Males sometimes wrestle each other
to earn mating rights. Pregnant females then lay about 30 eggs,
which they bury in the earth until they hatch eight months later.
In the absence of males,
female Komodo dragons have an alternative means of reproduction. As they
possess both male and female sex chromosomes, female dragons can reproduce
asexually in a process called parthenogenesis.
Diet
As the dominant predators
on the islands they inhabit, Komodo dragons have a diverse diet. They consume
almost anything, including carrion, deer, pigs, smaller dragons, and even large
water buffalo. When hunting, Komodo dragons rely on camouflage and patience,
lying in wait for passing prey. When a victim ambles by, the dragon springs,
using its sharp claws and serrated, shark-like teeth to eviscerate its prey.The
Komodo dragon has venom glands loaded with toxins that lower blood pressure,
cause massive bleeding, prevent clotting, and induce shock. Dragons bite down
with serrated teeth and pull back with powerful neck muscles, resulting in
large gaping wounds. The venom then accelerates the loss of blood and sends the
prey into shock.
Animals that escape the
jaws of a Komodo will only feel lucky briefly. Dragons can calmly follow an
escapee for miles as the venom takes effect, using their keen sense of smell to
home in on the corpse. A dragon can consume a staggering 80 percent
of its body weight in a single feeding.
Threats to Survival
While asexual reproduction
allows female Komodo dragons to replenish their population—an evolutionary
advantage—it has a significant drawback: This reproduction process only results
in sons. The lack of other females within a population has led to evidence of
inbreeding. The reptile’s reluctance to stray far from home exacerbates the
issue as the species’ population declines and fragments.Humans have
significantly impacted the survival of the Komodo dragon. Activities such as
habitat destruction for land clearance and poaching pose serious threats to
this species. Even tourism, while beneficial in some aspects, can disrupt the
dragons’ mating process and alter their natural behavior. These factors led the
government of Indonesia to consider temporarily closing Komodo Island, one of
the primary habitats of these creatures, to tourism. However, tourism also
plays a crucial role in conservation efforts, providing an economic incentive
for locals to protect the Komodo dragon.
Conservation Efforts
In response to these
threats, Indonesia established the Komodo National Park in
1980 to protect the Komodo dragon and its habitat. This 700-square-mile
refuge is home to a variety of species, including the orange-footed
scrub fowl and Timor deer. It also supports a rich marine environment with
whales, dolphins, sea turtles, sharks, corals, sponges, manta rays, and over a
thousand species of fish.
Now recognized as a UNESCO World Heritage site, Komodo National Park has implemented patrols to prevent poaching and works with local communities to raise awareness about the importance of protecting this unique species.
Gharial: An Introduction
The Gharial, also known as the gavial or the fish-eating
crocodile, is a crocodilian in the family Gavialidae1. It is among the longest
of all living crocodilians. Mature females are 2.6 to 4.5 m (8 ft 6 in to 14 ft
9 in) long, and males are 3 to 6 m (9 ft 10 in to 19 ft 8 in)1.
Habitat
Gharials inhabit clear freshwater river systems, congregating at river bends where the water is deeper1. They are not well-suited for land and generally only leave the water to bask in the sun or to nest1. They are found in the northern part of the Indian subcontinent1.
Geographical Range
Gharials were once found
from Pakistan to Myanmar. However, their range has now shrunk to two countries:
India, specifically along the Chambal, Girwa, and Son Rivers; and Nepal, along
the Narayani River.
Appearance and Behavior
A typical gharial can reach
a length of 12 to 15 feet and weigh up to 2,000 pounds.
Gharials regulate their body temperature by basking in the sun to warm up or
resting in shade or water to cool down.
Unique Characteristics
Male gharials sport a large
growth on their snout called a ghara, the Hindi word for “mud
pot.” Males use their gharas to vocalize and blow bubbles during mating
displays.
Reproduction
Gharials congregate to mate
and make nests during the dry season. Females lay eggs in sandbanks along
slow-moving sections of water. The eggs incubate for 70 days,
and hatchlings will stay with their mothers for several weeks or even months.
Feeding Habits
Unlike other crocodilians,
gharials do not stalk and lunge at their prey. Their snouts contain sensory
cells that can detect vibrations in the water. By whipping their heads from
side to side, they zero in on fish and grab them in their jaws, which are lined
with more than a hundred teeth. While adults primarily eat fish, their
offspring also consume insects, crustaceans, and frogs.
Threats to Survival
The International Union for
Conservation of Nature classifies the gharial as critically endangered.
The biggest threats it faces are related to human activities.
Since the 1940s, the
gharial’s numbers have declined by as much as 98 percent due
to hunting for traditional medicine and drastic changes to their freshwater
habitats. For instance, human manipulation of river flows has caused certain
areas to dry out, making survival more difficult for water-reliant gharials.
Young gharials are also susceptible to being caught in fishing nets, which can
lead to injury or drowning.
Conservation Efforts
Concerns about the
gharial’s status have led to numerous conservation efforts in recent decades.
The Indian government granted the species full protection in
the 1970s with the aim of reducing poaching.
In the 1970s and 1980s, conservation groups in India and Nepal initiated rear and release programs. These programs have introduced more than 6,000 captive-bred gharials into the wild. Unfortunately, due to the lack of effective monitoring, the success of these programs remains unclear.
Flying Snakes: A
Reality in South and Southeast Asia
The image of airborne snakes may seem like a figment
of imagination, but it’s a reality in the jungles of South and Southeast Asia.
In the Air: Gliders, Not Flyers
The term “flying snake” is
somewhat misleading. Barring a strong updraft, these animals can’t actually
gain altitude. They’re gliders, using the
speed of free fall and contortions of their bodies to catch the air and
generate lift.
The Art of Gliding
Once thought to be more parachuters than gliders,
recent scientific studies have revealed intricate details about how these
limbless, tube-shaped creatures turn plummeting into piloting. To prepare for take-off, a flying snake will slither
to the end of a branch, and dangle in a J shape. It propels itself from the branch with the lower half
of its body, forms quickly into an S, and flattens to about twice its normal
width, giving its normally round body a concave C shape, which can trap air. By undulating back and forth, the snake can actually
make turns. Flying snakes are technically better gliders than
their more popular mammalian equivalents, the flying squirrels.
Flying Habits
While scientists are
uncertain about the frequency and exact reasons why flying snakes fly, it’s
likely that they use their aerobatics to escape predators, move from tree to
tree without descending to the forest floor, and possibly even to hunt prey.
Population and Species
There are five
recognized species of flying snake, found from western India to the
Indonesian archipelago. Knowledge of their behavior in the wild is limited, but
they are thought to be highly arboreal, rarely descending from the canopy. The
smallest species reach about 2 feet in length and the largest
grow to 4 feet.
Diet and Venom
Their diets vary depending on their range, but they are known to eat rodents, lizards, frogs, birds, and bats. They are mildly venomous snakes, but their tiny, fixed rear fangs make them harmless to humans.