Conservationists call for urgent measures to safeguard the declining population of Olive Ridley turtles
Published : 28 Feb 2024, 01:02 PM
The Olive Ridley sea turtles, renowned for their unique characteristic of returning to their birthplace to lay eggs, are facing an existential threat on their journey back to the shores of Bangladesh's Cox's Bazar.
Human activities have rendered the beach inhospitable while the sea waters are also fraught with danger for these marine creatures.
The perilous environment has led to a significant decline in the number of mother turtles making their way to the beach, which in turn has resulted in a decrease in the quantity of eggs laid over the last 15 years.
The once-common sight of Olive Ridley turtles visiting the beach for nesting, an event known as 'Arribada', or "arrival by sea" in Spanish, is becoming a rarity.
The beaches are seeing fewer turtles due to the hostile conditions created by human interference.
The grimness of the situation came to bear in the first two months of 2024 when 95 dead Olive Ridley turtles were discovered along the beaches.
Since Feb 13, there have been no sightings of turtles laying eggs.
Experts suspect injuries, such as cuts to their flippers and throats, caused by entanglement in fishing nets resulted in the turtles' deaths.
According to them, the decline in the turtle population in Cox's Bazar can be attributed to several factors, including excessive fishing near the shore, unregulated tourism activities, and high levels of light and noise pollution.
DEADLY NETS
The nesting season for Olive Ridley sea turtles, typically stretching from November through the last week of March, sees mother turtles venture ashore on full moon or new moon nights to lay their eggs. However, a disturbing trend emerged on the beaches of Cox's Bazar this time.
From January to Feb 27, researchers from the Bangladesh Oceanographic Research Institute (BORI) encountered the harrowing sight of 95 dead Olive Ridley turtles scattered across various sections of the beach.
Since Feb 25, 10 turtles have been found dead in parts of the coastline, including two each in Daryanagar Parasailing Point, Royal Tulip Beach, Baradailpara, and Hazampara Teknaf Beach, as well as one each at Bailyakhali Beach and Motherbunia.
Before that, another 24 dead turtles were discovered on Feb 23, taking the tally past 50 in the last fortnight alone.
The turtles washed ashore in various areas ranging from Sonar Para of Ukhia Upazila along Cox's Bazar’s Marine Drive Road to Teknaf Beach, including Teknaf's Hakimpara and Baharchara, Inani Beach, and the Sonadia coast of Maheshkhali Upazila.
Tariqul Islam, a senior scientific officer at BORI, explained that these turtles typically lay more eggs in February.
"All the dead turtles were of the Olive Ridley species, with each carrying eggs in their stomachs. Most showed signs of entanglement in fishing nets. Some had their fins bound by net ropes, and others suffered injuries like cut flippers and bruises on their necks," he said.
Tariqul explained that the turtles typically wash ashore seven to 10 days after their deaths, by which time their bodies become swollen and begin to decompose. These turtles have since been buried.
Prof Towhida Rashid, the director general of BORI, said the country lacks specialised facilities for turtle forensics, making it difficult to definitively determine the cause of their deaths.
However, preliminary assessments suggest that the Olive Ridley turtles likely perished due to entanglement in discarded fishing nets, commonly referred to as ghost nets, and complications from their flippers being ensnared.
Mohammad Muslem Uddin, chair of the Department of Oceanography at Chattogram University, provided further insight into the grim situation.
He explained that fishermen often resort to severing the turtles' flippers to expedite their release from the nets and to prevent damage to the fishing gear. This cruel method is often chosen over the time-consuming process of safely freeing the turtles.
Evidence of net entanglement was found in 80 percent of the dead turtles, he said.
The presence of large jellyfish on the beaches, a primary food source for the turtles, suggests that the fishing grounds are frequented by both turtles and jellyfish.
BORI official Tariqul pointed out that the physical characteristics of Olive Ridley sea turtles, particularly the size of their flippers, naturally prevent them from getting entangled in the smaller fishing nets often used near the coast.
He believes the larger gill nets, typically used by fishing trawlers, are more likely to pose a significant threat to these turtles.
Despite regulations mandating these trawlers to operate within designated deep-sea zones, many venture closer to the shore, increasing the likelihood of inadvertently capturing marine life, including turtles, he said.
Many of the turtles suffering from injuries, such as wounds from ropes, sharp objects, and amputated flippers, ultimately perish at sea due to their inability to swim, Tariqul explained.
The issue not only affects turtles but also other marine species. In recent times, washed-up dolphins, porpoises, king crabs, and jellyfish have been on the beach.
To further understand and address this issue, a BORI team plans to conduct a sea search in the upcoming days to identify the precise cause behind these incidents.
An official from Cox's Bazar's South Forest Division shed light on a contributing factor to this problem, noting that Bangladesh does not possess modern trawlers equipped for deep-sea fishing.
As a result, many trawlers operate closer to the shore, frequently crossing their designated fishing boundaries. This practice likely leads to the accidental capture of coastal turtles and other marine creatures in their nets, he said.
ARRIBADA IN PERIL
The Olive Ridley, scientifically named Lepidochelys olivacea, stands as the smallest among the seven sea turtle species.
These turtles typically measure around two to two and a half feet in length and can weigh up to 50kg. With an estimated lifespan of about 50 years, they are currently listed as vulnerable on the International Union for Conservation of Nature (IUCN) Red List.
Olive Ridleys are known to inhabit the warm waters of the South Atlantic, Pacific, and Indian oceans.
While they spend the majority of their lives in the open sea, they exhibit a unique nesting behaviour known as Arribada during the breeding season. This term, meaning "arrival by sea" in Spanish, describes the event where thousands of mother turtles return to their natal beaches to lay eggs.
Sayeed Mahmood Belal Haider, the chairman of the Bangladesh Fisheries Development Corporation (BFDC), said that while Olive Ridleys gather in large numbers on sandy beaches to nest during the breeding season, the remarkable Arribada phenomenon is conspicuously absent in Bangladesh.
In contrast, it is noticeably prevalent on the beaches of India's Odisha.
Reports from Indian media in 2023 indicated that 503,719 female turtles laid their eggs at Gahirmatha and an impressive 637,000 at Rushikulya Beach, both in Odisha.
These nesting activities were observed in the Gahirmatha Marine Wildlife Sanctuary, situated across the Bay of Bengal from Cox's Bazar. The sanctuary, specifically within Nasi-1 and Nasi-2 islands, serves as a prime nesting site for these turtles.
In response to the need for conservation, the Odisha government in 1997 established a marine sanctuary extending 1,435 square kilometres from the Dhamra River mouth at Gahirmatha to Hukitola.
Fishing activities are strictly prohibited within this sanctuary during the Olive Ridley turtles' nesting period.
Haider emphasised the fascinating lifecycle of the Olive Ridley turtles. After spending around 19 years at sea, female turtles possess an extraordinary ability to navigate back to their birthplace to lay eggs.
This homing behaviour is exclusive to females, as male turtles do not return to the shore but continue their life in the ocean.
The return of mother turtles is believed to be an instinctual effort to safeguard their eggs from numerous natural and anthropogenic threats.
However, the increasing encroachment of human activities on nesting beaches and the degradation of the marine environment have escalated the risks these turtles face, endangering their survival and that of the broader marine ecosystem.
The condition of the turtles and their habitat is a growing concern for experts like Muslem Uddin from Chattogram University, who underscores the need for serene and undisturbed beaches for turtle nesting.
He points out the adverse impacts of infrastructure development on Maheshkhali and Matarbari coasts, which threaten the natural habitats essential for the turtles' reproduction.
Muslem warns that without immediate and effective conservation measures, the Olive Ridleys may never return to Bangladesh's shores, potentially disrupting their life cycle and further imperiling their existence.
SAVING OLIVE RIDLEYS
In March 2023, BORI accomplished a significant milestone in the conservation of Olive Ridley turtles by collecting 91 eggs, a first of its kind initiative for the organisation.
Remarkably, 83 of these eggs successfully hatched.
In addition to BORI, two private development organisations, Nature Conservation Management (NACOM) and Community Development Centre (CODEC), have also committed themselves to the cause of protecting and incubating turtle eggs found on the beaches.
BORI's Tariqul revealed that throughout the year, a total of 11,895 eggs from 103 turtles were discovered.
Although each turtle can lay between 100-120 eggs, the deaths of turtles have led to the loss of around 10,000 eggs.
"This year, we managed to collect 257 eggs. The two other organisations are also actively involved in egg protection efforts.”
The process of hatching these eggs employs two primary methods: in-situ, where the eggs are left to hatch in the exact location they were laid, and ex-situ, which involves relocating the eggs to a controlled environment or hatchery that simulates their natural nesting conditions.
The nesting sites for these turtles span approximately 710 square kilometers along the coast, from St Martin's to Sonadia Island.
Notably, certain areas such as St Martin's, Teknaf, Pechar Dwip, Himchari, Ukhia Sonarpara, Inani Beach, and Sonadia Island have seen higher concentrations of egg-laying activities.
Md Abdul Kaiyum, the NRM manager of NACOM's Eco Life Activity, shared insights into their ongoing efforts to conserve Olive Ridley turtles.
"Currently, we're nurturing 5,000 eggs in seven hatcheries from Sonadia to St Martin's. These eggs are expected to hatch within 60 to 70 days, after which the newborn turtles will naturally make their way to the sea," he said.
Kaiyum reminisced about the early days of his conservation work, pointing to a significant decline in turtle populations.
"Back in 2007, Sonadia Island alone would see 8,000-10,000 eggs. However, various barriers on our beaches have since hindered Arribada events, leading to a noticeable decrease in turtle numbers. Despite a recent uptick over the last few years, the alarming rate at which turtles are dying is very concerning."
He further detailed the nesting process, describing how mother turtles meticulously dig holes on secluded beaches at night to lay their eggs, using their flippers in a manner akin to hands. Once the eggs are laid, the turtles cover the nests with sand to conceal them.
Kaiyum also outlined the protective measures taken by organisations like NACOM.
"After the eggs are laid, our teams assess the safety of the nesting sites. In cases where the beach environment poses risks to the eggs due to potential predators, including humans and other wildlife, we relocate the eggs to hatcheries situated in safer locales," he said.
He highlighted the extensive migratory routes of these turtles, spanning from Bangladesh's shores and across the Bay of Bengal to countries like India, Sri Lanka, Thailand, and Malaysia.
BORI's Tariqul also shed light on the turtles' travels and their preference for nesting sites.
"These turtles embark on a journey spanning 15,000 to 19,000 kilometres to find the perfect nesting grounds, favouring beaches composed entirely of sand and avoiding areas with mud or mangroves," he said.
CALLS TO RAMP UP CONSERVATION EFFORTS
Tariqul attributed the recent surge in turtle deaths to the barriers, including fishing activities, they face while migrating to Cox's Bazar beaches to lay eggs.
He called on fishermen to exercise caution and steer clear of areas known for turtle congregations to minimise accidental captures.
Associate Prof Muslem Uddin from Chattogram University underscored the need for national consciousness and governmental intervention to safeguard marine wildlife, including turtles.
He warned of the ecological imbalance that could result from the decline of turtle populations, notably affecting fish ecosystems.
Muslem called for a thorough assessment of the environmental impact of coastal projects and urged the issuance of clear governmental guidelines on activities permissible in marine and coastal zones, while emphasising the importance of educating fishermen at the community level about marine conservation.
NACOM official Kaiyum detailed the various challenges marine life faces near coastal areas, pinpointing intensified trawling operations around Cox's Bazar, Bhola, Satkhira, and Khulna as significant threats.
He also brought attention to other detrimental practices endangering marine life, such as placing fishing nets too close to the shore, beach biking, excessive night lighting and noise pollution -- all occurring due to a lack of strict regulations.
BORI chief Towhida Rashid highlighted the need for engaging with fishing experts to tackle these issues effectively.
She announced plans for collaborative discussions with experts and stakeholders on Mar 2-3 to gather insights and jointly devise solutions, focusing on collaborative efforts rather than playing the blame game.
BFDC Chairman Haider suggested modifications to trawling practices to ensure turtles can escape from nets and highlighted the need to train fishermen on how to safely release entangled turtles.
He called for increased awareness and collective action among all stakeholders to protect marine biodiversity and maintain the health of the ecosystem.
He also referred to the implementation of Turtle Excluder Devices (TEDs) in trawling nets as a proven method to prevent sea turtles from getting caught.
TEDs allow turtles to exit nets safely, reducing turtle mortality rates by up to 97 percent, he said citing a study.
An official from Cox's Bazar South Forest Division called for enhanced coordination among government departments to protect marine wildlife and address the issue of overfishing.
Local residents looked back to the time around 2010 when minimal human activity on the beach supported the arrival of 30-40 turtles in groups, leading to thousands of hatchlings making their way back to the sea.
They expressed hope that with appropriate conservation measures and an optimal environment, Cox's Bazar's beaches could once again witness the Arribada phenomen, marked by the arrival of thousands of mother turtles and the return of millions of hatchlings to the sea.
[Writing in English by Arshi Fatiha Quazi]