GS Paper III
News Excerpt:
Rising global temperatures could lead to an increase in the nesting range of green turtles in the Mediterranean Sea, as per a study in Scientific Reports.
About the Green Turtles:
Significance of Green Turtle:
- Green turtles graze on seagrasses and algae, which maintains the seagrass beds and makes them more productive.
- Seagrass consumed by green turtles is quickly digested and becomes available as recycled nutrients to the many species of plants and animals that live in the sea grass ecosystem.
- Seagrass beds also function as nurseries for several species of invertebrates and fish, many of which are of considerable value to commercial fisheries and therefore important to human food security.
Issues highlighted in the report:
- Sea turtles are particularly susceptible to climate change, as their sex depends on incubation temperature.
- A warmer nest results in more females.
- Increasing temperatures in Queensland’s north, (Australia), linked to climate change, have led to virtually no male Green Sea turtles being born.
- Researchers developed a model to predict the suitability of a point on the Mediterranean coastline as a green turtle nesting location
- They found that sea surface temperature, sea salinity, and human population density most affected the suitability of a specific location as a nesting site.
- They also modelled how different greenhouse gas emission scenarios could affect the nesting range of green turtles in 2100, finding that -
- Progressively worse climate scenarios were associated with greater increases in the nesting range in the Mediterranean.
- Under the worst-case scenario, the nesting range increased by 62.4% points, including the North African coastline to Algeria, much of Italy and Greece, and the south Adriatic Sea.
- This increase in green turtle nesting range would bring them into increased contact with humans and urbanised beaches, which could negatively affect nesting success.
Other challenges faced by Green turtle:
- Fisheries bycatch: Sea turtles are accidentally caught in nets, hooks, and gillnets, causing bycatch and drowning.
- This serious hazard for green turtles is increasing as fishing activity expands.
- Habitat loss: Sea turtles rely on beaches for nesting, but uncontrolled development, human activities, and vehicular traffic have destroyed or disturbed these beaches worldwide.
- Green turtle feeding grounds, like seagrass beds, are also at risk due to pollution and sedimentation.
- Overharvesting and illegal trade: Green turtles are hunted and their eggs harvested globally. Trade of turtle parts for medicine is done in Asia, along with the Pacific and the West African region.
Way forward:
- SDG Goal 14 (Life below water): Conserve and sustainably use the oceans, seas and marine resources for sustainable development.
- Eliminating bycatch: Work with the fishing industry to switch to more turtle-friendly fishing hooks (“circle” hooks) and advocate for the use of devices that exclude turtles from nets.
- Protecting habitat: By establishing Marine Protected Areas (MPA) to ensure sea turtles have a safe place to nest, feed and migrate freely.
- This will also lead to ecotourism opportunities and offer alternative livelihoods.
- Satellite tracking: Satellite telemetry will allow researchers to track sea turtles as they swim from place to place.
- The data will tell where important feeding areas are and help understand migration patterns.
- Addressing overharvesting and illegal trade: Engage with local communities to reduce turtle harvesting and egg collection.
- Authorities should work to develop alternative livelihoods so that local people are no longer dependent on turtle products for income.
Prelims PYQ
Q. Consider the following statements: (UPSC 2019)
- Some species of turtles are herbivores.
- Some species of fish are herbivores.
- Some species of marine mammals are herbivores.
- Some species of snakes are viviparous.
Which of the statements given above are correct?
(a) 1 and 3 only
(b) 2, 3 and 4 only
(c) 2 and 4 only
(d) 1, 2, 3 and 4
