Wildlife study unveils hidden grasshopper haven in state
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Jaisalmer: A scientific survey conducted in the heart of Rajasthan's Desert National Park (DNP) has unveiled a rich diversity of Orthoptera, the insect order that includes grasshoppers, locusts and crickets.
Spanning an area of 3,162 sq km across the Jaisalmer and Barmer districts, this study highlights the ecological significance of these often-overlooked insects in the arid landscape.
The research team identified 24 distinct species of Orthoptera, including notable species such as Acrida turrita and Schistocerca gregaria, spanning 20 genera and 11 subfamilies across five families. The Acrididae family, comprising true grasshoppers, emerged as the most diverse group in the region's grasslands and scrublands.
The comprehensive survey, carried out between June 2021 and Dec 2024, was led by researchers Anshuman Pati, Indranil Paul and Sutirtha Dutta from the Wildlife Institute of India (WII) and the IUCN Grasshopper Specialist Group.
"This expansive grassland ecosystem is not only the last stronghold of the critically endangered Great Indian Bustard (GIB) but also a haven for an astonishing variety of insect life," said Anshuman Pati, lead researcher from WII.
Interestingly, the study revealed that species richness peaked during summer months, coinciding with the emergence of seasonal vegetation like Cenchrus biflorus and Lasiurus sindicus. Conversely, the monsoon and winter seasons yielded fewer species, likely due to habitat saturation and limited visibility during collection efforts. The research, published in the Journal of Threatened Taxa, employed standard sweep netting methods and careful documentation techniques.
"The study significantly enhances our understanding of Orthopteran diversity in the Thar Desert, a region that has often been overshadowed by research focused on its bird and mammal populations," Pati said. The findings emphasise the crucial role insects play as ecological indicators of grassland health, particularly in arid environments.
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Scroll.in
3 days ago
- Scroll.in
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'Since crocodilians, including gharials, have temperature-dependent sex determination, we suspected that rising ambient and nest temperatures, likely driven by climate change and habitat alterations, might be altering hatchling sex ratios and shifting population dynamics.' What the study found Between 2017 and 2019, the researchers monitored 17 gharial nests over three breeding seasons at Baroli and Nadigaon, which are key nesting sites in the National Chambal Sanctuary in Madhya Pradesh. These sites are part of a long-running conservation initiative, where eggs are collected annually to support the 'grow and release' programme, under which hatchlings are reared in captivity and later released into the Chambal and other gharial-inhabited rivers across India. Working along the remote stretches of the Chambal river posed numerous logistical challenges: difficult terrain, extreme heat, and the need to avoid disturbing nesting females. 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The constant temperature equivalent – a thermal metric that estimates how fluctuating temperatures affect embryo development in species with temperature-dependent sex determination – ranged from 30.5 degrees celsius to 34 degrees celsius during the critical sex-determining period. Cooler conditions were recorded in the bottom layers of the nest, while the top layers were consistently warmer. The modelled data revealed a strong female bias: on average, one male to every 3.2 females. Over 35% of the nests exhibited higher female-producing temperatures, and in nearly a third of the nests, all hatchlings were expected to be female. 'We couldn't physically confirm the hatchlings' sex, as it's still very difficult to determine the sex of such small individuals. Long-term monitoring is needed until they're big enough for reliable sexing techniques,' says Sharma. 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The Hindu
4 days ago
- The Hindu
World's highest bird death rates at Thar Desert wind farms
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A study by the Wildlife Institute of India (WII), published recently in Nature Scientific Reports, has estimated that bird mortality rates at wind farms are the highest in the world in India's Thar Desert. The study was conducted in a 3,000 sq. km desert landscape in Jaisalmer, Rajasthan, home to around 900 wind turbines and 272 bird species, including the critically endangered great Indian bustard. Across seven multi-season surveys, WII researchers searched for bird carcasses within a 150-m radius of 90 randomly selected wind turbines and found 124. The estimated annual bird mortality per 1,000 sq. km came up to 4,464 birds after correcting for non-detection due to vegetation cover or carcass degradation during the survey and due to carcass scavenging before the survey. The researchers conducted similar surveys at 28 randomly selected control sites (between 500 and 2,000 m of any turbine) to account for the natural mortality of birds and found no carcasses. 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The desert mortality estimates also included bird collisions with power lines linked to the wind turbines. The Gujarat and Karnataka study didn't include this cause. Per both studies, raptors were the most affected group of birds, echoing findings worldwide. 'Raptors are long-lived species that lay fewer eggs, and any additional mortality can lead to population-level impacts,' Selvaraj said. 'Their flight altitude and soaring flight behaviour means they are more vulnerable while manoeuvring rotating wind turbines.' Organisations like Birdlife International have proposed several mitigation measures to reduce bird collisions with wind turbines, including painting one of the turbine blades to increase visibility and shutting turbines down at a certain time of day or season. However, Selvaraj said he believes the most crucial step in mitigation is to carefully select the site of a wind farm. Avian Sensitivity Tool for Energy Planning (AVISTEP) is an open-source platform developed by Birdlife International that helps developers identify and avoid sites where renewable energy could affect birds. Selvaraj, previously with the Bombay Natural History Society, coordinated India's map for AVISTEP. 'The whole of India, including offshore areas, have been divided into different categories of avian sensitivity such as 'low', 'moderate', 'high', and 'very high',' Selvaraj said. 'While AVISTEP can serve as a guide, ground-level studies are crucial before installing wind farms,' he added. However, onshore wind energy projects in India aren't mandated to conduct an environmental impact assessment (EIA) before installation. From land to ocean Offshore wind farms are emerging as a valuable renewable energy resource worldwide. According to the Global Wind Energy Council, operational offshore wind capacity worldwide is currently around 83 GW. 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The rapid EIA report of the proposed offshore wind farm in the Gulf of Khambhat in Gujarat documented five marine mammals, including dolphins and sharks, and a reptile within the study area. While the report recognised that increased turbidity and noise levels during the construction phase of the wind farm may drive away highly sensitive species, it deemed the noise and vibrations during the operation phase to be 'limited'. Selvaraj said he doesn't agree with the report's inference that there are very few bird species passing through the study region. 'Gujarat and its coasts are a key area within the Central Asian Flyway and the African-Eurasian Flyway,' according to him. Per AVISTEP as well, the proposed location has a high avian sensitivity score. Thus, Selvaraj urged a longer, more thorough study to understand how migratory bird species use the area and the possible effects of wind farms on these birds. Nikhil Sreekandan is an independent journalist.
Time of India
24-07-2025
- Time of India
2-yr raptor ecology study begins in DNP with vulture tagging
Jaisalmer: A comprehensive study on raptor ecology has begun in Desert National Park (DNP) and surrounding areas to assess the status and local ecology of breeding raptors. Initiated by the Wildlife Institute of India (WII), the research project commenced on July 21 and will continue till July 2027. The study involves the capture and tagging of 36 vultures from various species, including the Tawny Eagle Vulture and Egyptian Vulture, to better understand their movement and breeding patterns. Under the guidance of Dr Govind Sagar Bhardwaj, director of WII, and led by senior scientist Dr Sutirtha Dutta, the team has already fitted two vultures with GPS transmitters and backpack harnesses. The first bird, a Tawny Eagle, was tagged and released on July 21 in the RKVY enclosure of DNP, while a juvenile Egyptian Vulture was tagged and released near the Gajaimata enclosure two days later. Both birds exhibited normal flight post-release. The study, approved under Section 12(A) of the Wildlife Protection Act 1972, also includes collection of biological samples from six individuals each of Red-headed Vulture, White-rumped Vulture, Indian Vulture, Egyptian Vulture, Tawny Eagle, and Laggar Falcon. The research aims to generate critical data on the spatial ecology and conservation needs of these threatened species. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like 15 most beautiful women in the world Undo Officials from WII highlighted the importance of the study in recommending measures to protect the vulnerable landscape of the Thar Desert. B M Gupta, divisional forest officer of DNP, emphasised that these efforts are crucial for the long-term conservation of raptors in the region.
