G. gangeticus probably the only living species in the
Fossil and morphological data on Tomistoma schlegelii
(false gharial) show closest resemblance to Crocodylidae.
But recent molecular data show closer resemblance to G.
gangeticus, causing some authors to place it in the
Gavialidae (Brochu, 2003).
"Gharial" originates from the Hindi word "ghara"
which is a clay pot with a long neck, much like the snout shape of an
adult male gharial.
Sometimes referred to as "gavial" which is probably a
misspelling of gharial. The Family and Genus names have not been
changed to reflect this error.
"gangeticus" means "of the Ganges (River)."
Other common names: long-nosed crocodile, gaviel du Ganges (Fr.),
Schnabelkrokodil (Gr.), Sansar (Pakistan), Chimpta (Nepal).
The Order Crocodylia, which includes all living crocodilians, originated around 100 million years ago (mid-Cretaceous). (St. John et al. 2012)
Crocodylians and birds are the only living representative of the ancient group
Archosauria, which included dinosaurs and pterosaurs (St. John et al. 2012)
A very small number of crocodylians exist today -- 23 species.
are 9,000 species of birds, their closest relatives.
A very early gharial-like fossil is known from Morocco's 60 million years-old rocks (Hua & Jouve 2004).
Although 12 fossil species have been
found in India, South America, Africa, and Europe, only one species
DISTRIBUTION & HABITAT
(Maskey et al., 1995)(Singh, 1991)(Whitaker & Basu, 1982)
Body Weight:Average: 159 - 181 kg (350 - 400 lbs), but largest individuals may approach weight of saltwater crocs at 680 kg (1,500 lbs) (Juengst
& Ahern, 2002) Body Length:Males 4 - 4.5 m (13 - 15 ft ), up to 6 m
(19.7 ft). Females 3.5 - 4 m (11.5 - 13 ft). Snout: Length is 3 1/3 to 5 1/2 times as long as it
is broad at the base.
One of the largest crocodilians, approaching the overall length of the saltwater crocodile.
Thick skin covered with smooth epidermal scales that do not overlap.
Osteoderms (bony plates) on the dorsal side serve as armor. (None on
Light tan or olive color with darker bands along back and tail.
Long, very narrow snout. Longest of all crocodilians.
Sharp, slender teeth (all alike in form) along length of snout; upper
teeth interlock with lower.
Thecodont teeth (Crocodylia and Mammalia) = rooted and set in sockets.
Unlike other reptiles, which are rootless and attached to the jaw,
and not set in sockets.
Most aquatic crocodilian.Tail laterally compressed; back feet webbed;
legs weak, can't lift body up off the ground.
Heads of Crocodiles,
showing snout lengths. From Bellairs,
porosus. D. Tomistoma
Bulbus nose of a male
Cartilaginous knob or ghara begins to develop at the tip of the male’s
snout around age 10. Forms a lid over the nostrils in males larger
than 3 m (9.8 ft)
Males may be slightly larger than females.
Other Physical Characteristics
Integumentary Sense Organs, or ISO's:
Tiny pits found on scales of entire body, including head and jaws.
Thought to detect vibrations or changes in pressure or salinity.
Probably assist in finding prey.
Found in all crocodilians.
Tapetum lucidum (reflective layer behind the retina) enables
Nictitating membrane: transparent membrane that slides
across the eye to protect it under water.
Muscles close the ear canal to prevent water from entering
Amount of time spent basking is seasonal. More hours are
spent basking in cooler winter months than during the hot
summer, and this may occur more often on rocks than on sand.
Typical basking pattern: Winter months -bask from 9:00 AM
until 4:00 PM. Summer months -come out several hours
earlier, spend 10:00 AM - 5:00 PM (hottest time of day) in
the water, return for a few hours in the evening.
Occasionally, very large animals have been observed basking
at night during the hottest time of year.
Individuals often return to the same basking spot, making
them more vulnerable to predators. But they are never far
from the safety of the water.
Gaping: Resting with jaws wide open.
Common among basking gharials (10-20 minute periods with head
raised ~20 degrees).
At midday during the hot season, juveniles and adults remain
submerged while holding heads out of water at a 20-30 o
Other activities: When not basking, time is spent in the water
resting and foraging.
Endothermic: must regulate body temperature by external means
Bask in the sun to increase body temperature; results in better
mobility and digestion
Gaping: cool brain and head by
Cool entire body by submerging under water and then lying on river
Social group: single adult male with rostrum knob and several females
Adult males are dominant to females and immatures.
Size most important factor in dominance.
Fairly social; bask in groups.
Adult males become territorial during the breeding season, but will
tolerate small and subadult males.
Females slightly territorial during nesting season, and will defend
nest and hatchlings. But nest communally and share nesting habitat
with other females.
Generally not aggressive towards one another, except during the
Courtship begins in December. Mating occurs in January and
February (dry season).
Female communicates readiness to mate by pointing snout upward.
Bulbous knob on male's snout thought to be important in breeding. May
act as visual identification for female, or as resonator of sound; see
The mating pair may stay under water for up to 30 minutes.
Reproduction cycle determined by hormones as well as day length and
Occurs in March and April,between cold winter months and monsoon.
Same approximate sites used each season.
Females dig pitcher-shaped holes in steep, sandy river banks at night
with hind feet.Eggs deposited, then covered with sand.
Sometimes trial nest holes are dug before egg deposition.
1-10 m ( ft.) from water's edge, about 50 cm (20 in.) deep.
Nest may be layered with sand in between.
Female guards nest, but male does not.
Clutch size: 12 - 100 eggs, but usually in the range of 28 to 60
. Number of eggs corresponds to size of female.
Egg size: Largest of any crocodilian species, 100-160 g (3.5 -
Incubation: Temperature dependent – 53-94 days (incubation
period shorter when temperature is higher). Female stays nearby for
Size: weight 75-130 g (2.6 - 4.6 oz), length 325-392 mm (12.8 - 15.4
Female does not bring the hatchlings to water in her mouth, as observed
in other crocodilians.
Group together, near the mother, for protection. Female protects
hatchlings for several weeks, but will allow male to approach. Male
does not actively protect hatchlings, but stays close and will carry
them on his back.
The sex of hatchlings is not determined by genes, but by temperature
during incubation. Higher temperatures result in a higher percentage
Maturity: Females ~3 m (9.8 ft) long at 7-10 years of age; males
~3.5 m (11.5 ft) long at 15-18 years of age; dependent on size more
Large knob at the tip of the rostrum in males begins to develop at
about 10 years of age.
Grow continuously until death.
Longevity (Whitaker, 1982)
Only longevity record is from a female at the London Zoo. Estimated age
Fishermen living near gharials estimate ‘the age of man’ or ‘over
Late maturity and large size suggests a long life span.
1970's: Active effort initiated to avoid extinction
Numerous sanctuaries created.
1972: Indian Wildlife Protection Act; prohibited hunting.
Active management programs began in 1975 in India, and 1978
Captive rearing: Collect and incubate eggs;
hand-rear hatchlings in captivity until they are big enough
to avoid predation; release back into the wild.
Some 3,000 gharials released into wild beginning in 1981 in India; 1500 adults subsequently estimated, with 200 in Nepal, Pakistan and Bangladesh (Whitaker 2007)
Present: Although conservation efforts initially were successful,
populations quickly plumeted and were not self-sustained; they are in very serious decline
Gharial decline follows the decline of other riverine taxa now endangered or nearly extinct including the Ganges River Dolphin (Platanista gangetica) and the Mugger crocodile (Crocodylus palustris) as well as many waterfowl and fish species. (Choudhury et al 2007)
Threats to survival
Poaching: for skin and meat; also for male's nasal knob (to be
used as an aphrodisiac).
Habitat destruction and competition due to rapidly growing human
Hydroelectric dams, sand mining of river banks, irrigation canals, riparian agriculture
Heavy commercial net-fishing removes food source, blocks access
to parts of the rivers, and entangles gharials.
Gharial Conservation Alliance (GCA) - international organization formed in 2007 dedicated to saving gharials; engage in conservation efforts through surveys, captive breeding and wild restocking programs, and lobbying
International Reptile Conservation Foundation. Website for pursuing the conservation of reptiles and amphibians and their ecosystems. This organization supports mobilization of volunteers, funding for specific programs, and logistcial assistance for projects.
- 3D images of gharial skull. Slow to load but worth the effort. Must
install QuickTime Viewer