![Bostami Turtle](https://upload.wikimedia.org/wikipedia/commons/d/d3/Bostami_Turtle.jpg)
The black softshell turtle or Bostami turtle (''Nilssonia nigricans''), previously placed in
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''
Aspideretes'', is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of freshwater turtle found in
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
(
Assam
Assam (; ) is a state in northeastern India, south of the eastern Himalayas along the Brahmaputra and Barak River valleys. Assam covers an area of . The state is bordered by Bhutan and Arunachal Pradesh to the north; Nagaland and Manipur ...
and
Tripura
Tripura (, Bengali: ) is a state in Northeast India. The third-smallest state in the country, it covers ; and the seventh-least populous state with a population of 36.71 lakh ( 3.67 million). It is bordered by Assam and Mizoram to the east a ...
) and
Bangladesh
Bangladesh (}, ), officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world, with a population exceeding 165 million people in an area of . Bangladesh is among the mos ...
(
Chittagong
Chittagong ( /ˈtʃɪt əˌɡɒŋ/ ''chit-uh-gong''; ctg, চিটাং; bn, চিটাগং), officially Chattogram ( bn, চট্টগ্রাম), is the second-largest city in Bangladesh after Dhaka and third largest city in B ...
and
Sylhet
Sylhet ( bn, সিলেট) is a metropolitan city in northeastern Bangladesh. It is the administrative seat of the Sylhet Division. Located on the north bank of the Surma River at the eastern tip of Bengal, Sylhet has a subtropical climate an ...
). It was long believed to be
inbred individuals of the
Indian softshell turtle (''A. gangeticus'' or ''N. gangeticus'') or the
Indian peacock softshell turtle
Indian peacock softshell turtle (''Nilssonia hurum'') is a species of turtle found in South Asia, and is listed on the IUCN Red List as a vulnerable species.
Geographical range
The Indian peacock soft-shell turtle is found in Bangladesh, India ...
(''A. hurum'' or ''N. hurum''), but while it is a close relative of the latter, it is a distinct species.
[Praschag ''et al.'' (2007)] In the 1800s it was believed these turtles were brought from Iran to Chittagong shrine pond by
Hazrat Bayezid Bostami. His turtles he had brought to this pond were treated as sacred and respected by the public. Previously declared
extinct
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
by the
International Union for Conservation of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
in 2002, these turtles were found still to exist in a temple's pond called the Hayagriva Madhava Temple located in Assam, and in Kalyan Sagar lake in Tripura Sundari Temple in Udaipur, Tripura, India.
Through conservation methods and protection of the species, some of these turtles can be found today throughout the wild, and scientists and environmental biologists are continuing to work hard to preserve this endangered species and their natural habitat. Their mitogenome represents relatedness to 19 other species of the Testudines. When looking at the phylogenetic tree, Nilssonia Nigricans are a species represented as sisters to Nilssonia formosa.
Habitat
Originally native to the lower
Brahmaputra River
The Brahmaputra is a trans-boundary river which flows through Tibet, northeast India, and Bangladesh. It is also known as the Yarlung Tsangpo in Tibetan, the Siang/Dihang River in Arunachali, Luit in Assamese, and Jamuna River in Bangla. It ...
, the only
population
Population typically refers to the number of people in a single area, whether it be a city or town, region, country, continent, or the world. Governments typically quantify the size of the resident population within their jurisdiction using a ...
ever reliably known consists of a small number of the species in a man-made pond which is part of the
Bayazid Bostami shrine at Chittagong, where they are dependent on humans for survival. To the locals and worshipers, the black softshell turtle is known as ''mazari'' ("
Mazar Mazar of Al-Mazar may refer to:
*Mazar (mausoleum); often but not always Muslim mausoleum or shrine.
Places
*Mazar (toponymy), a component of Arabic toponyms literally meaning shrine, grave, tomb, etc.
*Mazar, Afghanistan, a village in Balkh Pro ...
inhabitant"); specimens from this shrine were used in the first scientific description.
In a 2014 survey by Poribesh Banchao Andolon, a Bangladeshi private organization it was found that the amount of
oxygen dissolved in the pond water was 2.01 mg/L, whereas the favorable level is 5 mg/L.
In 2012, wildlife biologists of the Center for Advanced Research in Natural Resources and Management found a small population in the wild of Sylhet.
Two tiny wild populations were discovered in
Assam
Assam (; ) is a state in northeastern India, south of the eastern Himalayas along the Brahmaputra and Barak River valleys. Assam covers an area of . The state is bordered by Bhutan and Arunachal Pradesh to the north; Nagaland and Manipur ...
, in
Kaziranga
Kaziranga National Park is a national park in the Golaghat and Nagaon districts of the state of Assam, India. The park, which hosts two-thirds of the world's great one-horned rhinoceroses, is a World Heritage Site. According to the census held i ...
and in the Jia Bhoroli River which is a northern tributary of the
Brahmaputra
The Brahmaputra is a trans-boundary river which flows through Tibet, northeast India, and Bangladesh. It is also known as the Yarlung Tsangpo in Tibetan, the Siang/Dihang River in Arunachali, Luit in Assamese, and Jamuna River in Bangla. It ...
. Also, another temple population of these turtles was identified in the Kasopukhuri pond on Nilachal Hill, next to the
Kamakhya Temple
The Kamakhya Temple at Nilachal hills in Guwahati, Assam is one of the oldest and most revered centres of Tantra, Tantric practices. The temple is the center of the ''Kulachara Tantra Marga'' and the site of the Ambubachi Mela, an annual fes ...
at
Guwahati
Guwahati (, ; formerly rendered Gauhati, ) is the biggest city of the Indian state of Assam and also the largest metropolis in northeastern India. Dispur, the capital of Assam, is in the circuit city region located within Guwahati and is the ...
in
Assam
Assam (; ) is a state in northeastern India, south of the eastern Himalayas along the Brahmaputra and Barak River valleys. Assam covers an area of . The state is bordered by Bhutan and Arunachal Pradesh to the north; Nagaland and Manipur ...
. Another temple population is found in the kalyan sagar lake of
Tripureshwari temple,
Udaipur
Udaipur () (ISO 15919: ''Udayapura''), historically named as Udayapura, is a city and municipal corporation in Udaipur district of the state of Rajasthan, India. It is the administrative headquarter of Udaipur district. It is the historic capit ...
,
Tripura
Tripura (, Bengali: ) is a state in Northeast India. The third-smallest state in the country, it covers ; and the seventh-least populous state with a population of 36.71 lakh ( 3.67 million). It is bordered by Assam and Mizoram to the east a ...
. These turtles are also found in the pond in
Baneswar Shiva temple
Baneswar Shiva temple is at Baneswar in the Cooch Behar II CD block in the Cooch Behar Sadar subdivision of the Cooch Behar district in West Bengal, India.
Geography
Location
Baneswar Shiva temple is located at .
It is about from Cooch Behar ...
, a shiva temple in
Baneswar
Baneswar is a census town in the Cooch Behar II CD block in the Cooch Behar Sadar subdivision of the Cooch Behar district in West Bengal, India.
Etymology
The word 'Baneswar' came from Ban+eeswar. Ban was a 'king of Asura'. He carried out 'S ...
in the
Cooch Behar II
Cooch Behar II is a community development block (CD block) that forms an administrative division in the Cooch Behar Sadar subdivision of the Cooch Behar district in the Indian state of West Bengal.
Geography
Khagrabari, one of the constituent pan ...
CD block in the
Cooch Behar Sadar subdivision
Cooch Behar Sadar subdivision is a subdivision of the Cooch Behar district in the state of West Bengal, India.
Subdivisions
Cooch Behar district is divided into the following administrative subdivisions:
Administrative units
Cooch Behar Sad ...
of the
Cooch Behar district
Cooch Behar district () is a district of Indian state of West Bengal.
Formerly part of the Kamarupa kingdom, the area became the heart of the Kamata Kingdom in the 12th century. During the British Raj, the district was known as Cooch Behar st ...
in
West Bengal
West Bengal (, Bengali: ''Poshchim Bongo'', , abbr. WB) is a state in the eastern portion of India. It is situated along the Bay of Bengal, along with a population of over 91 million inhabitants within an area of . West Bengal is the fourt ...
,
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
.
Biology
Appearance
The black softshell turtle has an observably different appearance compared to that of a common turtle. This turtle, similar to all other softshell turtles, has a semi-flexible shell that is leathery, and does not obstruct movement as much as the average hardshell. The black softshell turtle also has a very distinct nose and face, with a tube like structure protruding from its nose resembling and functioning similar to a snorkel. The ligaments of this turtle are also much more distinct than those of the normal sea turtle or land tortoise, being that they have hand-like structures that are webbed, as opposed to other turtles like sea turtles who have a wider arm.
The softshell of the turtle does not protrude out from the body very far, and typically appears somewhat rigid with very little color and design.
The skin of the black softshell turtle is often black or dark brown, but can often appear with white to yellow spots that appear across the head and ligaments of the turtle.
Size and weight
The average Bostani turtle adult size can range from widths of 15 inches to 31 inches, and corresponding lengths of 13 inches to 28 inches. The average area of the species can range from 195 inches squared on the low end and 868 inches squared on the larger end. However, the highest recorded size for these turtles is a length of 35 inches.
The weight for the average female is around 120 pounds, while the weight of the males has not yet been recorded. However, these males are visually larger indicating strong chances of a larger corresponding weight.
Life span and mortality rate
The highest recorded age for the Bostani turtle has been determined by those living in the area directly, with claims that the oldest turtles present are approximately 150 years old.
However, this species has a high mortality rate at the beginning stages of life, with 94% of eggs without hatching capabilities. With an average clutch size of 20, this would allow for the survival of about one egg per two mating turtles.
Diet
With the species existing in very limited areas with high human traffic, these turtles have become dependent upon visitors for feeding. Visitors tend to feed a mixture of grains, fruits, and various meat products.
These interactions with direct feeding have created a dependence for these turtles on the people, since this species no longer has a need for hunting. This had made it hard to determine the natural diet of the species. However, with the ability to consume the foods provided by the people, their diet is commonly compared to that of other species within the same genus. These organisms are on the omnivore scale of the food consumption, consisting of plants and small animals like fish and worms.
Reproduction
![Feeding the turtles 01](https://upload.wikimedia.org/wikipedia/commons/9/9b/Feeding_the_turtles_01.jpg)
''Nilssonia nigricans'' are oviparous organisms, in which they reproduce by laying their young as eggs to be hatched. Softshell turtles are known to mature slowly with the males prepared to breed in their fourth year. The female population could take up to seven to nine years to mature.
A group of eggs is known as a clutch and a female black soft shelled turtle can lay anywhere between 10 and 38 eggs in her clutch. The baby turtles will grow in their eggs for 92–108 days before hatching.
Recently the hatching rate for this specific species has been decreasing due to these species being endangered.
Behavior
Hibernation
Hibernation takes place during the late autumn season until the spring for softshell turtles. They bury themselves at the bottom of a river/lake in the mud. Food is not as essential as oxygen during this period. Oxygen is needed at a reduced rate than normal and the turtles practice a technique called “pharyngeal breathing”.
This means that they pump water in and out of their throat (pharynx) that contain microvillus projections of small blood vessels. This structure provides them with greater surface area to absorb more oxygen.
Near-extinction in the wilderness
![Baizid Bostami's Mazar 002](https://upload.wikimedia.org/wikipedia/commons/c/cf/Baizid_Bostami%27s_Mazar_002.JPG)
In 2002, the
International Union for Conservation of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...
classified the species as
Extinct in the Wild
A species that is extinct in the wild (EW) is one that has been categorized by the International Union for Conservation of Nature as known only by living members kept in captivity or as a naturalized population outside its historic range due ...
. In 2004, 408 turtles were found in the pond of the Bayazid Bastami shrine. According to the shrine committee staff, 90 more turtles were hatched in the pond in 2007, 74 in 2008, 96 in 2009, 28 in 2010, 45 in 2012 and 40 in 2014.
In 2017, a singular wild turtle was found in the wetlands of
Old Akuk Village in
Wokha District
Wokha District (Pron:/ˈwəʊkə/) is a districts of Nagaland, district of Nagaland state in India. It is the home of the Lotha Nagas. Gastronomically, it known for its variety of fermented bamboo shoots (bastenga). It holds an important place ...
,
Nagaland
Nagaland () is a landlocked state in the northeastern region of India. It is bordered by the Indian states of Arunachal Pradesh to the north, Assam to the west, Manipur to the south and the Sagaing Region of Myanmar to the east. Its capital cit ...
. DNA from the specimen sent to Bangladesh was tested and ultimately confirmed that it was a member of the black softshell species.
This extinction has been caused by human intervention, specifically the migration of people into the habitat and the contamination of water and land following this movement. The land of Bangladesh that ''N. nigricans'' have been able to occupy currently had been tested for conditions of survival and mating. The survival rate of juvenile ''N. nigricans'' is relatively low due to a low mortality of egg hatching and juvenile survival following hatching.
Human captivity of black softshell turtles for religious contexts seems to both benefit and harm turtle populations. Shrines keep these turtles in areas protected from outside predators, but these ponds are not suitable for sustained repopulation efforts. In
Hinduism
Hinduism () is an Indian religion or '' dharma'', a religious and universal order or way of life by which followers abide. As a religion, it is the world's third-largest, with over 1.2–1.35 billion followers, or 15–16% of the global p ...
, the black softshell turtle represents an incarnation of the deity
Kurma
Kurma ( sa, कूर्म; , 'Turtle', 'Tortoise'), is the second avatar of the Hindu preserver deity, Vishnu. Originating in Vedic literature such as the Yajurveda as being synonymous with the Saptarishi called Kashyapa, Kurma is most comm ...
. Worshipers come and feed the turtles in the ponds human foods such as biscuits. Such dietary items are harmful to the turtles, often leading to malnourishment.
![Feeding the turtles 03](https://upload.wikimedia.org/wikipedia/commons/3/32/Feeding_the_turtles_03.jpg)
Human intervention has also caused a push towards extinction with intentional methods of poisoning. In 2006 there was a mass poisoning of the turtles within the Bostami Shrine pond by poachers in the area. This event occurred within the research period, as the turtles were under heavy observations and were protected from this event, while this not being the first time this method had been used. In this case many of the fish utilized by the ''N. nigricans'' for food had been poisoned, making nutrition unsustainable for the turtles. This same poisoning also changed the oxygen levels in the water, making it unsustainable for the turtles. A waiting period had passed to ensure oxygen levels were rich in the water, indicating a sustainable environment, in turn allowing the release of the species.
Conservation efforts
Since 2013, TSA India has worked diligently to improve conditions at selected temple ponds in Assam where these turtles were discovered. Many of the ponds were eutrophic and overcrowded and often, turtles were fed human food as religious offerings. The turtles showed signs of poor nutrition and a lack of suitable nesting space resulted in eggs being deposited in areas where there was little chance of hatching. The goal of the project is to eventually rear and release juveniles from these captive colonies to supplement depleted wild populations. As part of that initiative, the TSA India team camped at the Nagshankar temple in April to observe nesting in the 40-45 adult females at that location. At that time, the team transferred ten nests to a hatchery and protected four nests onsite.
With TSA's efforts 44 turtles have hatched so far. The team is currently expanding a
headstarting Headstarting is a conservation technique for endangered species, in which young animals are raised artificially and subsequently released into the wild. The technique allows a greater proportion of the young to reach independence, without predation ...
facility at Nagshankar temple to accommodate the turtle's hatchlings of 2016. Neonates and juveniles cannot be released back into the temple pond due to predation by larger turtles and exotic fish. For this reason, the team acquired an earthen pond in the nearest village to provide space for the fast-growing juveniles, improving survival prospects for this extremely rare softshell.
In 2018, Das et al. had collected population sizes of ''N. nigricans'' from 2006 to 2012. The population size had shown a gradual increase over time, indicating that the calculated area per turtle had decreased in accordance. He indicated that without an increase in habitat size, the carrying capacity of the species will be reached quicker. This can decrease the overall growth of the species and not allow it to grow past the current conservation status.
In 2011, Dr. Jayaditya from the Help Earth
NGO found a grouping of black softshell turtles in a temple pond in Hajo,
Assam
Assam (; ) is a state in northeastern India, south of the eastern Himalayas along the Brahmaputra and Barak River valleys. Assam covers an area of . The state is bordered by Bhutan and Arunachal Pradesh to the north; Nagaland and Manipur ...
. He revitalized contributions aimed towards saving and replenishing the species once again. He and his team embanked the sides of the temple pond and made adjustments to simulate a natural river system and create an ecosystem more conducive to the turtle's natural habitat. Thereafter, they observed a positive egg ratio produced around the temple premises. The State Zoo of Assam is playing an important role in this conservation project, serving as the location where baby turtles are reared for six months. When deemed fit and healthy, and capable of surviving, the young turtles are released into the wild. As of 2016, the State Zoo of Assam has released 300 turtles. Now 16 temples in Assam are helping in this important project. Similar conservation efforts have been undertaken in Tripura in Tripura sundari temple, matabari, udaipur, tripura, to protect the indigenous populations of bostami turtles.
References
Bibliography
*
Further reading
*
Anderson J (1875). "Description of some new Asiatic Mammals and Chelonia". ''
Annals and Magazine of Natural History, Fourth Series'' 16: 282–285. (''Trionyx nigricans'', new species, pp. 284–285).
*Praschag P, Gemel R (2002). "Identity of the black softshell turtle ''Aspideretes nigricans'' (Anderson 1875) with remarks on related species". ''Faunistische Abhandlungen'' 23: 87–116.
*Praschag P, Hundsdörfer AK, Reza AHMA. Fritz, U (2007). "Genetic evidence for wild-living ''Aspideretes nigricans'' and a molecular phylogeny of South Asian softshell turtles (Reptilia: Trionychidae: ''Aspideretes, Nilssonia'')". ''
Zoologica Scripta'' 36 (4): 301–310. (''Nilssonia nigricans'', new combination).
(HTML abstract).
External links
*
Photo of MazariPhoto of Bostami turtle
{{Taxonbar, from=Q201055
Nilssonia (turtle)
Reptiles of Bangladesh
Reptiles of India
Reptiles described in 1875