PANGOLINS
Pangolins, often called
“scaly anteaters,” are covered in tough, overlapping scales. These burrowing
mammals eat ants and termites using an extraordinarily long, sticky tongue, and
are able to quickly roll themselves up into a tight ball when threatened. Eight
different pangolin species can be found across Asia and sub-Saharan Africa.
Poaching for illegal wildlife trade and habitat loss have made these incredible
creatures one of the most endangered groups of mammals in the world.Pangolin species vary in size
from about 1.6kg (~3.5 lbs) to a maximum of about 33kg (~73 lbs). They vary in
color from light to yellowish brown through olive to dark brown. Protective,
overlapping scales cover most of their bodies. These scales are made from
keratin — the same protein that forms human hair and finger nails. Overlapping
like artichoke leaves, the scales grow throughout the life of a pangolin just
like hair; scale edges are constantly filed down as pangolins dig burrows and
tunnel through the soil in search of termites and ants. Pangolin undersides do
not have scales, and are covered with sparse fur. Unlike African pangolins,
Asian pangolins also have thick bristles that emerge from between their scales.
With small conical heads and jaws lacking teeth, pangolins have
amazingly long, muscular, and sticky tongues that are perfect for reaching and
lapping up ants and termites in deep cavities. Pangolins have poor vision, so
they locate termite and ant nests with their strong sense of smell. A pangolin’s
tongue is attached near its pelvis and last pair of ribs, and when fully
extended is longer than the animal’s head and body. At rest a pangolin’s tongue
retracts into a sheath in its chest cavity. A pangolin’s stomach is muscular
and has keratinous spines projecting into its interior. Usually containing
small stones, the stomach mashes and grinds prey in much the same manner as a
bird’s gizzard.
Pangolin limbs are stout and well adapted for digging. Each paw
has five toes, and their forefeet have three long, curved, claws used to
demolish the nests of termites and ants and to dig nesting and sleeping
burrows. Pangolins shuffle on all four limbs, balancing on the outer edges of
their forefeet and tucking their foreclaws underneath as they walk. They can
run surprisingly fast, and will often rise on their hind limbs to sniff the
air. Pangolins are also capable swimmers, and while some pangolin species such
as the African ground pangolin (Manis
temmincki) are completely terrestrial, others, such as the African
tree pangolin (Manis
tricuspis), are adept climbers, using their claws and
semi-prehensile tails to grip bark and scale trees.There are eight pangolin species. All pangolins belong to the
genus Manis in
the family Manidae, which is the only family within the order Pholidota.
Pangolins’ closest living relatives are the Xenarthrans –
anteaters, armadillos, and sloths.Four pangolin species occur
across Asia: the Indian pangolin, the Chinese or Formosan pangolin, the Malayan
or Sunda pangolin, and the Palawan pangolin. Four species are found in Africa
south of the Sahara Desert: the Cape or ground pangolin, the tree pangolin, the
giant pangolin, and the long-tailed pangolin. The four Asian pangolins are
distinguished from the African species by the presence of bristles which emerge
from between the scales.
Pangolins are found in a variety of habitats including tropical
and flooded forests, thick brush, cleared and cultivated areas, and savannah
grassland; in general they occur where large numbers of ants and termites are
found. Asian pangolins in particular are threatened by loss of habitat due to expanding agriculture and other
human uses. Pangolins dig deep burrows for sleeping and nesting that contain
circular chambers. Large chambers have been discovered in terrestrial pangolin
burrows that were big enough for a human to crawl inside and stand up. Some
pangolin species such as the Malayan pangolin also sleep in the hollows and
forks of trees and logs.It is unknown how long pangolins can live in the wild, though
pangolins have reportedly lived as long as twenty years in captivity.
These solitary mammals are nocturnal and highly secretive, thus it
is difficult for scientists to study them in the wild, and many mysteries
remain about their behavior and habits. Some pangolin species such as the
Chinese pangolin sleep in underground burrows during the day, and others
including African tree pangolins and Malayan pangolins are known to sleep in
trees. They emerge in the evening to forage for insects. Pangolins are well
adapted for digging: they dig burrows with their strong front legs and claws,
using their tails and rear legs for support and balance. Tunneling underground,
they excavate the sides and roofs of passages by pushing up and from side to
side with their tough scaled bodies. They use their front and hind feet to back
accumulated soil toward the burrow entrance, and vigorously kick dirt out of
the entrance up to a meter or more.
Chinese (Manis
pentadactyla) in temperate areas spend the winter months in deep
burrows. The winter burrows are strategically excavated near termite nests that
provide a lasting food source. In Chinese legend pangolins are said to travel
all around the world underground, and in the Cantonese language the name for
pangolins translates to “the animal that digs through the mountain,” or
“Chun-shua-cap,” which translates to “scaly hill-borer.”
While pangolins species share many characteristics and habits,
there are also differences. African tree pangolins (Manis tricuspis) are arboreal tree
climbers, while African ground pangolins (Manis
temmincki) are terrestrial ground dwellers. And some, including all
three Asian species, are opportunistic and can be found foraging both in trees
and on the ground. Indian pangolins found in Sri Lanka reportedly live in the
rain forest canopy where fruit and flowers that attract ants occur, instead of
at ground level where it is very dark and the food supply is limited. Some
pangolin species even have semi-prehensile tails—they can grasp and hang from
branches with their tails, which aids them in climbing.
Pangolin scales provide good defense against predators. When
threatened, pangolins can quickly curl into a ball, protecting their
defenseless undersides. They also deter predators by hissing and puffing, and
lashing their sharp edged tails. Pangolins, dependent on their strong sense of
smell, identify their territories by scent marking with urine and secretions
from a special gland, and by scattering feces. Scientists suspect that these
odors advertise dominance and sexual status, and may also help individuals
recognize each other.
Pangolins live predominantly on a diet of ants and termites, which
they may supplement with various other invertebrates including bee larvae,
flies, worms, earthworms, and crickets. This specialist diet makes them
extremely difficult to maintain in captivity—they often reject unfamiliar
insect species or become ill when fed foreign food. Wild pangolins locate
insect nests using a well developed sense of smell. Voraciously digging ants
and termites from mounds, stumps, and fallen logs with their claws, they use
their extremely long sticky tongues to capture and eat them. Pangolins’ insatiable appetite for insects gives them an important
role in their ecosystem: pest control. Estimates indicate that one adult
pangolin can consume more than 70 million insects annually. Pangolins have
special muscles that seal their nostrils and ears shut, protecting them from
attacking insects. They also have special muscles in their mouths which prevent
ants and termites from escaping after capture.
Male and female pangolins are sexually dimorphic: the sexes differ
in weight. In most species, males are 10-50 percent heavier than females, while
Indian pangolins can be up to 90 percent heavier. Pangolins reach sexual
maturity at two years, and most pangolins give birth to a single offspring,
though two and three young have been reported in the Asian species. Gestation
periods range from 65-70 days (Indian pangolin) to 139 days (Cape and Tree
pangolins). When born, pangolins are about six inches long and weigh about 12
ounces (.75 lbs). Their scales are soft and pale, and begin to harden by the
second day. Pangolin mothers nurture their young in nesting burrows. A mother
will protectively roll around her baby when sleeping or if threatened. Babies
nurse for three to four months, but can eat termites and ants at one month. At
that time the infant begins to accompany the mother outside of the burrow,
riding on the base of her tail as she forages for insects (pictured right).
Pangolins are disappearing in
China and across their ranges in East and Southeast Asia. They have become the
most frequently seized mammal in Asia's illegal wildlife trade, as smugglers
sell the creatures to meet culinary and medicinal demand.The pangolin decline comes
despite national legislation that bans hunting the species throughout its
Southeast Asia range. Meanwhile, the Convention on
International Trade in Endangered Species of Wild Fauna and Flora (CITES)prohibits
the pangolin trade across borders.Chris Shepherd, acting director
for Southeast Asia for the wildlife trade monitoring network TRAFFIC, said the pangolin plight reflects the
difficulty in enforcing the international wildlife convention."The ongoing massive-scale trade in these species does
highlight a failure of the Convention," Shepherd said. "CITES is a
very useful conservation tool, but like any tool, it is only useful when
effectively used."Pangolin researchers gathered
earlier this month in Singapore and concluded that increased demand from China
has led to "great declines" in pangolin populations across Cambodia,
Vietnam, and Laos. Some researchers concluded that pangolins from Indonesia and
Malaysia now supply the bulk of East Asian markets. The panel said traders are importing pangolins into
China from as far away as Africa, where four of the eight known species of the
anteater live.
Pangolins have been a staple of traditional Chinese medicine for
thousands of years, but growing human populations and greater wealth across
China have increased demand. Pangolin fetuses, scales, and blood are used in
medicine, the meat is considered a delicacy, and stuffed pangolins are sold as
souvenirs.
The decline in pangolin populations and intensified efforts to
curb the illegal trade have led to rising prices for pangolin products -
further enticing organized crime rings to smuggle the endangered animals. A
kilogram of pangolin scales that earned only 80 yuan (US$10) in the early 1990s
would now yield 1,200 yuan ($175) on the black market, according to Zhang Yue,
a wildlife trade expert in China's State Forestry Administration.An estimated 25,000-50,000 wild
pangolins lived in China in 2000, according to a national survey. Populations
in Guangdong and Hunan provinces have since dropped as low as 10 percent of the
2000 estimate, and populations in Hainan, Henan, and Jiangsu provinces are
likely extinct, according to a study led by Li Zhang, the technical director of Conservation International's China program.Tallies of the creatures are
generally unreliable, however, due to their solitary and nocturnal habits. The International
Union of Conservation of Nature acknowledges that there is "very little
information available on the population status anywhere in the species' range."
But the organization concurs that pangolin populations are decreasing."Trade surveys and interviews with hunters and traders in
many parts of Southeast Asia have indicated that populations of pangolins are
in serious decline and in many locations are gone altogether," Shepherd
said.
According to data on wildlife seizures, at least 49,662
pangolins have been smuggled from Indonesia since 2002. In Thailand, border
officials seized 7,734 pangolins between 2003 and June 2008.Most governments in the pangolins' range have implemented bans
on hunting or trading the animals, and violators face harsh penalties with
potential imprisonment. Range countries acknowledge, however, that enforcement
is generally weak due to a lack of wildlife management personnel and funding.Shepherd said that even in countries with strict penalties,
violators are rarely punished to the full extent of the law. "Penalties
need to serve as a deterrent and until this happens, the trade will
continue," he said.China is a member of CITES, but the country permits some
pangolin consumption to respect medicinal traditions. Pangolin scales may be
used in clinical treatment and in the manufacturing of patented Chinese
medicines. Both uses are permitted only in designated hospitals, not through retail
sales.
To control the pangolin influx from Indonesia - where Shepherd
said that middlemen regularly establish "buying stations" in villages
before shipping the anteaters to China - Indonesian wildlife officials have
proposed a legalized trade based on a quota system. The market would be
strictly monitored and limited to a period of three to five years.Gono Semiadi, a biologist at the Indonesia Institute for
Sciences, said at a panel during the Singapore conference that a legal market
would allow wildlife officials to create a rivalry between legal and illegal
traders, enabling officials to better understand trade routes and trafficking
data.Given the high market value for pangolins, continued demand, and
difficulty in enforcing wildlife laws in Indonesia, some conservationists are
concerned that traders would illegally exceed the legal pangolin exchange
quota.
Prof. John Kurakar
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