Olive ridley turtle: India

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The return of turtles has brought cheer among marine biologists who lament that nearly 80-90% of beaches in Maharashtra have been damaged to such an extent that it becomes unfavourable for Olive ridleys to lay eggs. “While today is certainly a day of celebration, I cannot help but think of so many other beaches which have been destroyed due to encroachments and other illegal activities,” pointed out Dr Deepak Apte, marine biologist and head of Bombay Natural History Society. However, he added that it is commendable that consistent efforts by the citizens to clean Versova beach have led to this rare turtle nesting site there.
 
The return of turtles has brought cheer among marine biologists who lament that nearly 80-90% of beaches in Maharashtra have been damaged to such an extent that it becomes unfavourable for Olive ridleys to lay eggs. “While today is certainly a day of celebration, I cannot help but think of so many other beaches which have been destroyed due to encroachments and other illegal activities,” pointed out Dr Deepak Apte, marine biologist and head of Bombay Natural History Society. However, he added that it is commendable that consistent efforts by the citizens to clean Versova beach have led to this rare turtle nesting site there.
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==Odisha==
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===Erosion pushes turtle nests 14km in Odisha/ 2024===
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[https://epaper.indiatimes.com/article-share?article=14_04_2024_001_010_cap_TOI  Neha Madaan, April 14, 2024: ''The Times of India'']
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Pune: A Zoological Survey of India (ZSI)-Pune study found the world-famous Olive Ridley turtle nesting ground at Gahirmatha Marine Wildlife Sanctuary in Odisha has shifted a staggering 14km northwards over the last 30 years owing to severe coastal erosion caused by climate change and human activities.
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The peer-reviewed study, published in leading scientific journal Marine Pollution Bulletin by Elsevier, has analysed shoreline changes from 1990 to 2022 using satellite imagery and the digital shoreline analysis system software. Dr Basudev Tripathy, scientist, ZSI-Pune, described the findings as a matter of concern for the future of Olive Ridley Arribada (mass nesting that recently started at Gahirmatha).
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''' Turtle nesting zone shift leads to fears of crowding, egg loss '''
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Federal University of Pernambuco-Brazil and Federal University of Paraíba-Brazil were also involved among others in the study, which covered 929 transects across four zones in the nesting habitat.
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 +

“The marine sanctuary hosts one of world’s largest congregations of these endangered marine reptiles. During the annual Arribada, millions of Olive Ridleys converge on Gahirmatha’s sandy beaches to lay eggs. However, rampant erosion has drastically reshaped the coastline, forcing the turtles to shift their nesting ground northwards by 14km, from the mainland to an adjacent island, after which there is no space,” Tripathy said.
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 +

According to Tripathy, the turtles are forced to lay eggs in a limited space as their number is far more than the area available. “This can lead to overcrowding and substantial egg loss. For instance, if 10,000 turtles lay eggs one night and depart, and then another 1,000 turtles arrive to lay eggs, the newcomers may be forced to dig up the previously established nests because of lack of space. Consequently, the eggs in those disturbed nests are likely to be crushed or exposed, rendering them nonviable,” Tripathy explained.
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 +

For shoreline change analysis, the study focused on the coastal stretch from the Mahanadi river mouth in the south to Dhamra port in the north. This coastline was divided into four zones based on natural landmarks, such as river mouths and sea beaches, as well as anthropogenic features like ports.
“Zone I was from Mahanadi river mouth to Hukitola bay and Zone II was from Hukitola bay to Brahmani river mouth. Zone III (identified as the most vulnerable segment) included erosion-prone Pentha and Satabhaya Sea beaches. Despite mitigation efforts, erosion remains a critical concern in this zone. Historically, Olive Ridley turtle mass nesting occurred here. But severe erosion has caused the nesting site to shift further north. Zone IV, from Maipura river mouth to Dhamra port, is the current location for the Olive Ridley turtle mass nesting, particularly around Wheeler Island,” Tripathy said.
The analysis revealed that Zone III, from Barunei river mouth to Maipura river mouth, experienced the most significant erosion, with 89.2% of the transects showing such trends. Themean shoreline change rate for the entire study period (1990-2022) was half a centimetre per year.
 +
 +

In 2020-2021, approximately 90% of transects experienced erosion, coinciding with a roughly 50% decline in mass nesting in 2021, Tripathy said. “Similarly, during 2015-2016, erosion affected about 78% of transects, and there was a significant decrease in the number of mass nesting turtles in 2016 compared to the year before. This decline was possibly linked to habitat loss, specifically the reduction in beach length suitable for nesting.” Tripathy said.
 +
 +

Odisha coast, particularly in Gahirmatha marine wildlife sanctuary region, has experienced significant erosion because of both natural and human-induced factors, the study revealed. The natural causes include severe floods, frequent cyclonic events and storm surges, as well as heavy monsoonal rainfall, the study stated.
 +
 +

Manmade factors exacerbating erosion include coastal modifications that gradually increased erosion in Zone III. “While Gahirmatha marine wildlife sanctuary is protected, nearby developmental activities can indirectly impact it. Coastal interventions like installing erosion control structures in nearby beaches/ports divert wave action, intensifying erosion within the sanctuary’s beaches and threatening turtle nesting habitats. A holistic approach, considering ripple effects on adjacent ecosystems, is crucial,” said Tripathy.
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[[Category:Fauna|T OLIVE RIDLEY TURTLE: INDIAOLIVE RIDLEY TURTLE: INDIA
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[[Category:India|T OLIVE RIDLEY TURTLE: INDIAOLIVE RIDLEY TURTLE: INDIA
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[[Category:Pages with broken file links|OLIVE RIDLEY TURTLE: INDIAOLIVE RIDLEY TURTLE: INDIA
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=Population, dwindling=
 
=Population, dwindling=

Latest revision as of 20:43, 15 April 2024

Olive ridley turtles, India; In the above picture, “this year” means 2016; Graphic courtesy: The Hindu, March 5, 2016

This is a collection of articles archived for the excellence of their content.

Contents

[edit] In brief

K N Murali Sankar, Hope Island is a graveyard for Olive Ridleys: Jan 12, 2017: The Hindu

Perilous journey

The turtles, which are protected under the Wildlife (Protection) Act, commence their journey from the Indian Ocean during their mating season in October and November. When they reach the Bay of Bengal, the females lay eggs on the beaches. Even as the destination for a majority is Gahirmatha in Odisha, the sandy stretches of Hope Island of the Coringa Wildlife Sanctuary have turned into a breeding area for a few hundred turtles every year.

A female lays 100 to 150 eggs in a pit dug by it carefully and leaves the shore after covering the hollow with sand. Six weeks later, the newly hatched turtles start the journey to their Indian Ocean habitat. Records show 482 turtles laid eggs in 2016.

[edit] Conservation measures

[edit] 2023: missile testing paused

Riyan.Ramanath, Dec 9, 2023: The Times of India

Bright light, loud sounds from missile tests affect turtles

Bhubaneswar : The decision to stop missile-testing at Wheeler Island off Odisha coast during the Olive Ridley nesting season from January to March and other measures to save the vulnerable sea turtles were announced on Friday by a committee headed by Odisha chief secretary P K Jena.
The small turtles are hunted for food and their oil. Unhatched eggs and shells on the sand are used as fertilisers.


“The turtle nesting site is close to Wheeler Island. Since missile testing involves flashes of strong light and thunderous sound, the turtles get distracted,” Susanta Nanda, principal chief conservator of forests (wildlife), said.
Around 6.6 lakh sea turtles also nest at the Rushikulya rookery in Ganjam district. The Odisha government has already banned fishing across that section of the coast from November 1 till May 31.


The committee highlighted the need to issue advisories to organisations, institutions, and industrial houses along the coast to stick to outdoor lighting regulations, the chief secretarysaid. The wildlife division has urged the director of the Integrated Testing Range (ITR) at Chandipur in Balasore to provide space outside the periphery of Wheeler Island to set up seasonal forest camps.
Using this as a base, marine police will undertake joint sea patrolling with the forest department, while the Paradip Port Authority will provide a trawler to the mangrove forest division for vigilance duties.


“The DRDO will also nominate a nodal officer for better coordination with the forest department for the safety of the Olive Ridleys,” an official said.
The collectors and SPs of six districts – Ganjam, Puri, Jagatsinghpur, Kendrapada, Bhadrak and Balasore — have been told to coordinate with the forest department for the annual turtle protection drive.
The Rajnagar mangrove division has been provided two sections of 10 armed policemen each for sea patrolling. The rest of the five divisions have been given a section each.

[edit] Habitat

[edit] Mumbai

[edit] 2018: re-appearance

Vijay Singh, Olive ridleys back in Mumbai after 127-wk clean-up drive, March 23, 2018: The Times of India

2018: The 80 hatchlings have brought cheer to marine biologists who say 80-90% of Maharashtra’s beaches have become inhospitable for turtles
From: Vijay Singh, Olive ridleys back in Mumbai after 127-wk clean-up drive, March 23, 2018: The Times of India

Turtles Return To Versova Beach After 2 Decades

For the first time in two decades, at least 80 newly hatched Olive ridley turtles were spotted at Versova beach on Thursday morning, waddling towards the sea.

Environmentalists attributed the “happy phenomenon” to the sustained efforts by lawyer-activist Afroz Shah and his team over 127 weeks to clean Versova beach. “This is indeed very good news for our Versova beach. The 80 Olive ridley turtles hatched in the morning and made a dash towards the sea,” said Shah. “Earlier, this beach was very dirty, with piles of plastic trash. No sea turtles were hatching here as garbage is a huge hurdle for them to cross. But now, thanks to the Clean Versova Beach drive, we are all blessed to have seen these newly hatched Olive ridleys.”

Activists and animal welfare groups together ensured the little ones navigated their way into the sea safely from the hatching site which was 30-35m from the shoreline.

As the news spread, morning walkers and locals thronged the beach to enjoy the experience. Social networking sites were also abuzz with photographs and videos of the turtles. “I have witnessed something surreal today. A life changing experience. 80 Olive Ridley turtles walking back into the sea,” tweeted Shaunak Modi of Marine Life of Mumbai, a group promoting marine life welfare in the city.

State chief forests conservator (mangroves cell) N Vasudevan said the department was happy to see the photographs and videos of the turtles on the beach. However, he said: “Some locals, who later went to the beach, informed my department that they could not find any egg shells. I do not know if their doubts are real or not, but if we get any formal intimation on it, I will have to inquire into the matter.”

Shah added that a Mumbai-based forest official also came to the beach in the afternoon to do a panchanama after being informed about turtle hatchings. “For the last few weeks, we had been noticing turtles coming up to the beach and digging into the sand. We had also contacted a marine biologist to learn more and are today happy that so many hatched,” he told TOI.

Environmentalist D Stalin said, “This is a very good development. However, care should be taken that the lights at the beach are made dimmer and the area cordoned off till the nesting period is over, as human poachers are a threat for these turtles.”

The return of turtles has brought cheer among marine biologists who lament that nearly 80-90% of beaches in Maharashtra have been damaged to such an extent that it becomes unfavourable for Olive ridleys to lay eggs. “While today is certainly a day of celebration, I cannot help but think of so many other beaches which have been destroyed due to encroachments and other illegal activities,” pointed out Dr Deepak Apte, marine biologist and head of Bombay Natural History Society. However, he added that it is commendable that consistent efforts by the citizens to clean Versova beach have led to this rare turtle nesting site there.

[edit] Odisha

[edit] Erosion pushes turtle nests 14km in Odisha/ 2024

Neha Madaan, April 14, 2024: The Times of India

Pune: A Zoological Survey of India (ZSI)-Pune study found the world-famous Olive Ridley turtle nesting ground at Gahirmatha Marine Wildlife Sanctuary in Odisha has shifted a staggering 14km northwards over the last 30 years owing to severe coastal erosion caused by climate change and human activities.


The peer-reviewed study, published in leading scientific journal Marine Pollution Bulletin by Elsevier, has analysed shoreline changes from 1990 to 2022 using satellite imagery and the digital shoreline analysis system software. Dr Basudev Tripathy, scientist, ZSI-Pune, described the findings as a matter of concern for the future of Olive Ridley Arribada (mass nesting that recently started at Gahirmatha).


Turtle nesting zone shift leads to fears of crowding, egg loss

Federal University of Pernambuco-Brazil and Federal University of Paraíba-Brazil were also involved among others in the study, which covered 929 transects across four zones in the nesting habitat.


“The marine sanctuary hosts one of world’s largest congregations of these endangered marine reptiles. During the annual Arribada, millions of Olive Ridleys converge on Gahirmatha’s sandy beaches to lay eggs. However, rampant erosion has drastically reshaped the coastline, forcing the turtles to shift their nesting ground northwards by 14km, from the mainland to an adjacent island, after which there is no space,” Tripathy said.


According to Tripathy, the turtles are forced to lay eggs in a limited space as their number is far more than the area available. “This can lead to overcrowding and substantial egg loss. For instance, if 10,000 turtles lay eggs one night and depart, and then another 1,000 turtles arrive to lay eggs, the newcomers may be forced to dig up the previously established nests because of lack of space. Consequently, the eggs in those disturbed nests are likely to be crushed or exposed, rendering them nonviable,” Tripathy explained.


For shoreline change analysis, the study focused on the coastal stretch from the Mahanadi river mouth in the south to Dhamra port in the north. This coastline was divided into four zones based on natural landmarks, such as river mouths and sea beaches, as well as anthropogenic features like ports.
“Zone I was from Mahanadi river mouth to Hukitola bay and Zone II was from Hukitola bay to Brahmani river mouth. Zone III (identified as the most vulnerable segment) included erosion-prone Pentha and Satabhaya Sea beaches. Despite mitigation efforts, erosion remains a critical concern in this zone. Historically, Olive Ridley turtle mass nesting occurred here. But severe erosion has caused the nesting site to shift further north. Zone IV, from Maipura river mouth to Dhamra port, is the current location for the Olive Ridley turtle mass nesting, particularly around Wheeler Island,” Tripathy said.
The analysis revealed that Zone III, from Barunei river mouth to Maipura river mouth, experienced the most significant erosion, with 89.2% of the transects showing such trends. Themean shoreline change rate for the entire study period (1990-2022) was half a centimetre per year.


In 2020-2021, approximately 90% of transects experienced erosion, coinciding with a roughly 50% decline in mass nesting in 2021, Tripathy said. “Similarly, during 2015-2016, erosion affected about 78% of transects, and there was a significant decrease in the number of mass nesting turtles in 2016 compared to the year before. This decline was possibly linked to habitat loss, specifically the reduction in beach length suitable for nesting.” Tripathy said.


Odisha coast, particularly in Gahirmatha marine wildlife sanctuary region, has experienced significant erosion because of both natural and human-induced factors, the study revealed. The natural causes include severe floods, frequent cyclonic events and storm surges, as well as heavy monsoonal rainfall, the study stated.


Manmade factors exacerbating erosion include coastal modifications that gradually increased erosion in Zone III. “While Gahirmatha marine wildlife sanctuary is protected, nearby developmental activities can indirectly impact it. Coastal interventions like installing erosion control structures in nearby beaches/ports divert wave action, intensifying erosion within the sanctuary’s beaches and threatening turtle nesting habitats. A holistic approach, considering ripple effects on adjacent ecosystems, is crucial,” said Tripathy.

[edit] Population, dwindling

The Hindu, February 27, 2016

Nivedita Ganguly

Their beaches eroding and disturbed by human interference, fewer turtles are returning to nest every year

Every winter, the Olive Ridley turtles begin returning to the beaches of the Eastern coast to lay their eggs. Theirs is a treacherous journey. Trawlers and fishing boats are a threat for them, lights on shore confuse them, and they are routinely disoriented by human disturbances along the beach. But a more obstinate problem awaits the turtles lucky enough to make it to shore: in many places, beach erosion, which has been more pronounced post cyclone Hudhud, has left them with little place to dig a good nest.

In part the problem is not only the extensive loss of beach due to the severe erosion this season. As the endangered turtles lumber out of the surf in the darkness of a balmy spring night to look for a spot to nest, it is a combination of factors – human disturbances and unfavourable environmental conditions – that are resulting in disorienting these highly sensitive marine creatures.

Forest officials and environmentalists have expressed concern over the dwindling numbers of the eggs spotted on the Visakhapatnam coast this time.

Like every year, the Forest Department has set up two hatcheries – one at R.K. Beach and another at Jodugullapalem – a project being carried out at the cost of Rs 6 lakhs. However, according to the figures provided by the Forest Department, there is a drop in the number of eggs collected in the month of January this year as compared to the corresponding period last year. In 2014, nearly 2,900 eggs were collected in January alone, which were kept in the hatcheries. The figure has dropped to 2,100 this year for the month of January. Overall, 3,078 eggs were collected last year. Interestingly, the maximum egg collection happened in the month of January last year.

“This time, there have been many factors leading to the disturbance of the nesting area of the Oliver Ridley turtles. One of the factors is the massive erosion that has affected major portions of the R.K. Beach, one of the main nesting grounds of the turtles. The beach stretch is now less. To assess the exact extent of the impact on turtle eggs, we will have to wait for a couple of more weeks,” says P. Ram Mohan Rao, Divisional Forest Officer.

Volunteers are keeping guard of the hatcheries and the hatchlings will be released in a month’s time.

Classified as ‘Vulnerable’ by the International Union for Conservation of Nature (IUCN) several Olive Ridley turtles lay eggs during this time of the year along the Visakhapatnam coast, considered a sporadic nesting zone. The enclosed hatchery protects the eggs from predators like dogs and visitors to the beach who flock the area unaware of the eggs. Incidentally, the Olive Ridley Turtles take 25 to 30 years to reach adulthood but the survival rate of the young ones is abysmally low.

While the shrinking beach stretch is one of the concerns, the alarming frequency of deaths of Olive Ridley turtles along the coast continues to haunt the forest department and environmentalists. “We have recently spotted carcasses of eight Olive Ridley turtles at the beach opposite Sagar Nagar. However, there were no signs of injuries,” Ram Mohan Rao adds.

Researchers and environmentalists, however, have a different theory to share behind the mysteriously dwindling numbers of the turtle eggs. “Erosion may just be one part of the problem. A much larger issue haunts the Olive Ridleys and that is human interference. Tourist activities have increased substantially along the Vizag beaches, especially the R.K. Beach, one of the main nesting grounds of the turtles. Due to this, the fecundity rate (number of eggs laid at a time) goes down. The turtles may be going through fear psychosis due to human disturbances resulting in lower eggs being laid,” points out Prof. D.E. Babu of Dept. of Zoology, Andhra University.

While conservationist say they want to help the turtles, but they cannot agree how. Every time someone proposes a remedy, someone else is quick to rebut on how it will only make things worse. Because the possible solutions involve access to the beach, a crucial part of Vizag’s growing tourism industry, the arguments are bitter.

In fact, experts suggest that fewer and fewer turtles are returning to nest every year, hinting at a possible migration of turtles from the Vizag coast to a different spot. “Mortality rates are high due to the conflict between the turtles and the fishing community,” says Prof. Babu. Interestingly, this time red tidal waves were spotted at certain critical zones of the coast like the R.K. Beach and Lawsons Bay, which are caused due to “harmful plankton” and are hazardous for the aquatic species. “Turtles have a natural tendency to stay away from such zones,” he adds.

[edit] Reasons for declining population

K N Murali Sankar, Hope Island is a graveyard for Olive Ridleys: Jan 12, 2017: The Hindu


Mechanised fishing boats are dealing the turtles a mortal blow as they come to breed

Carcasses of Olive Ridley turtles are washing ashore on Hope Island’s beaches, indicating that the breeding cycle of the endangered species has been dealt a severe blow in 2017 by mechanised fishing boats.

As these fishing boats scour the Bay of Bengal coastline, there is gloom among conservationists and forest department officials that this year will be bad for the turtles.

Though the egg laying has not yet begun, personnel from the wildlife wing of the Forest department have spotted 54 carcasses on the shores of Hope Island in just one month. “In the entire six-month season last year, we spotted 152 carcasses. But this year the numbers seem to be on the rise,” A. Sunil Kumar, Forest Range Officer said.

“Owners of mechanised boats are not taking precautions to protect the turtles. Most of them are crushed under the boats and succumb to injuries,” said K. Thulsi Rao, State project coordinator of the EGREE Foundation that works to conserve flora and fauna in the sanctuary.

The Fisheries Department tried to encourage the mechanised boat owners to fit a Turtle Excluder Device (TED) to their trawl nets to allow the animals to pass, 10 years ago. Of the 422 boats, few have opted for the device due to lack of sensitisation. “The device is not available in the open market,” said S. Angeli, Deputy Director of the Fisheries department.

[edit] See also

Olive ridley turtle: India

Turtles: India

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