Latest news with #NationalCentreforBiologicalSciences
New Indian Express
6 days ago
- Health
- New Indian Express
Harmful chemicals clip wings, imperil humans
The National Centre for Biological Sciences has found a drastic 25 percent decline in India's bird population over the last two and a half decades. Such a trend would affect soil nutrient cycles, pollination, seed dispersal and ecosystem balance, besides triggering a cascading effect on public health. The study highlights the poor understanding in India about the consequences of pesticides, which are implicated in the decline of open-habitat birds and insectivores, depriving the birds of their prey and leading to their population decline. Pesticides are widely understood to be the main reason for the decline of insects, which in turn has affected several bird species worldwide. Among the main villains is a class of pesticides called neonicotinoids, which are chemically similar to nicotine and are rampantly used in agriculture and veterinary medicine in India. Neonicotinoids have raised global concerns due to their harm to beneficial insects like bees and other pollinators. This led to the ban of three neonicotinoids by the European Commission in 2018. But their continued unregulated use in India has led to prey deprivation for grassland and raptor bird species like the tawny eagle, greater spotted eagle, saras crane, great Indian bustard, Indian roller, Bengal florican and common pochard. Also blamed are changing agriculture patterns, water pollution, silt accumulation, unscientific desilting and poor lake rejuvenation that has affected wetland and aquatic birds like the northern pintail duck, tufted duck, greater flamingo, Eurasian spoonbill, black-capped kingfisher, Baillon's crake, spot-billed pelican, lesser adjutant, painted stork and pied kingfisher.
New Indian Express
7 days ago
- Health
- New Indian Express
Toxic farmlands, pesticide use pushing grassland birds to the brink: NCBS study
BENGALURU: Increasing and unregulated use of chemicals like insecticides and pesticides – especially neonicotinoids – and change in agricultural patterns have drastically affected grassland bird species across India. This is compromising soil nutrient cycle, pollination, seed dispersal and eco-system engineering in which the threatened bird species play a key role. This is bound to have an adverse impact on public health ultimately, says a study by Bengaluru-based National Centre for Biological Sciences (NCBS). The NCBS researchers point out that avian species are not just aesthetically important, but are valuable tools in the large food-chain and agricultural pattern. They feed on insects, bees and other pests. They noted that while many western countries have banned the use of pesticides and fertilizers, unregulated usage continues in India, affecting local and migratory bird species. Similar is the case with the continued use of banned drugs like the Diclofenac and non-steroidal anti-inflammatory drugs (NSAIDs) - painkillers given to cattle and consumed by humans. This has forced a drastic decline in populations of all six Indian vulture species. Neonicotinoids are a class of insecticides chemically similar to nicotine, and are being rampantly used in agriculture and veterinary medicine. They are absorbed by plants and transported throughout their tissues, including pollen and nectar. Birds like tawny eagle, Indian bustard at risk from toxic farmlands Neonicotinoids have raised concerns due to their potential harm to beneficial insects like bees and other pollinators, and bird species dependent on them. The NCBS study points to rampant and unregulated use of neonicotinoids, depriving grassland and raptor bird species like the Tawny Eagle, Greater Spotted Eagle, Saras Crane, Great Indian Bustard, Indian Roller, Bengal Florican and Common Pochard, of their prey. This has forced a decline in populations of these bird species.
The Hindu
7 days ago
- Science
- The Hindu
A beetle-fungi combo threatens plantations in rubber capital Kerala
Rubber plantations in Kerala have been under threat since a beetle-fungus alliance has been attacking trees, causing severe leaf fall and rapid drying. Researchers at the Kerala Forest Research Institute in Thrissur recently identified the parasite to be the ambrosia beetle (Euplatypus parallelus). In their new study, published in Current Science, the beetle has been reported to share a mutualistic relationship with two fungal species, Fusarium ambrosia and Fusarium solani. This is the first report of F. solani in association with the adult ambrosia beetles. Fungi in the galleries Earlier, farmers working in the rubber plantations in the Irrity-Kannur region of Kerala noticed latex oozing from the barks of rubber trees. Under the Tree Health Helpline project, they alerted researchers from the Institute, insect ecologist Jithu Unni Krishnan said. Ambrosia beetles get their name from the ambrosia fungi that call the beetle their home. The name 'ambrosia' is not taxonomic but ecological. These beetles are native to Central and South America. They were first reported in India in the cashew trees of Ponda, Goa, in 2012. These beetles attack dead or infected trees, although they're also known to attack stressed trees. At times, the stressed trees release ethanol, a volatile compound that the ambrosia beetles can sense and attack. The beetles don't feed on the woody bark of trees; the fungi do. The beetles bore tunnels called galleries in the bark, carry fungi into the galleries, and farm the fungi to concentrate nutrients. The beetles and their larvae feed on nutrient-rich fungal mycelia. The fungi also release enzymes that weaken the wood, allowing beetles to penetrate deeper. In other insect hosts, the fungi are present in sacs called mycangia. In the present study, however, the team didn't find mycangia in the ambrosia beetle. Krishnan said that it's of interest to study how the fungal species interact with each other while coexisting in a beetle without the mycangia. Long time to heal The beetle-fungus association harms trees in many ways. Aside from weakening the structure, the duo causes severe leaf fall, trunk drying, and in some cases even tree death. The infection also affects total latex production from rubber trees, causing economic and agricultural losses. To combat the infection, experts follow specific methods, such as using antifungal agents, removing the infected part of trees, burning or chipping away any part that displays holes, and preventive measures such as using traps for ambrosia beetles. Further, once a tree is infected, it takes a long time to heal. 'The systemic infections progress through the plant xylem, blocking the xylem vessels. Moreover, proliferation of the fungus inside the xylem leads to sporulation, which leads [it] to secrete several enzymes, weakening the wood strength and showing death in distinct parts of the tree,' Amey Redkar, reader at the National Centre for Biological Sciences, Bengaluru, an independent expert working on Fusarium oxysporum, also a plant pathogen, said. Controlling a fungal infection in plants is difficult. The fungi reside in deeper parts of an infected plant, where insecticides or fungicides often don't reach. 'Once [fungi] have progressed systemically, it's too late to save a plant from it. Many Fusarium sp. spread either through soil or can also be carried by insect vectors,' Redkar added. 'As these pathogens have adapted to outcompete neighboring microbes to reach their vascular niche, they have evolved to modulate the surrounding microbiome.' Future team-ups A few species of ambrosia beetles, including Euplatypus parallelus, are invasive and threaten horticulture and silviculture worldwide. Being flying insects, they can access a variety of trees. 'It can infest to my understanding more than 80 species of broadleaf trees, including cashew, teak, coconut, and coffee,' Krishnan said. While the beetle has coevolved with its fungal partners, it may in future associate with other pathogenic fungi, posing a bigger threat to plantations. Likewise, Fusaria sp. are very virulent and known to expand their host range. 'The concern is how many indigenous virulent pathogenic fungi are likely to associate with this insect and thereby broaden the host range and impact of this insect,' Krishnan said. Fusarium fungi infect beetles as well as other organisms, including spiders, frogs, and humans. These fungiare opportunistic pathogens in humans, meaning they can affect those with a compromised immunity, posing a significant health risk to workers in rubber plantations, as well as other plants and animals within an ecosystem. Much to lose The destructive power of the beetle-fungi association and the risk of other pathogenic fungi teaming up with the beetles together portend alarm. According to experts, the possibility calls for an action plan to mitigate and prevent further attacks. Since the number of invasive ambrosia species is increasing as well, Krishnan said policymakers and researchers should step up, collaborate, and provide solutions to manage infections. India is the world's sixth-largest producer of rubber and the second-highest in terms of productivity. Kerala produces 90% and accounts for 72% of India's rubber cultivation area. While there are reports of successful phytosanitary measures in coniferous trees, the same measures may not work on broad-leaf trees such as rubber and teak. The infection also makes other economically significant plants, such as coffee, cashew, mango, and coconut, vulnerable to infections. To prepare, experts recommend management strategies be designed based on the geographic location of the plantations. 'Things that are applicable to other parts of the world may not be applicable to Kerala or South India,' Krishnan said. Redkar added that sustainable treatments, such as using antagonistic fungi that can compete with the pathogenic onesor using microbial consortia with a diversity of bacterial species that can live inside plants, can offer promising results in mitigating fungal infections in plants. Rohini Karandikar is a science communicator, educator and facilitator. She currently works at TNQ Foundation as a consultant.
Hans India
03-07-2025
- General
- Hans India
Similipal tigress Zeenat pregnant, claims forest official
Bhubaneswar: Tigress Zeenat, which escaped from Similipal National Park and roamed across Odisha, West Bengal and Jharkhand, is now suspected to be pregnant, a senior forest department official said. Captured in Bankura district of West Bengal after a dramatic 23-day journey through three States, Zeenat was brought back to Similipal and kept in a soft enclosure from January 1, where she was observed for several weeks. 'She was found fit and healthy during her stay in the enclosure. On April 17, Zeenat was released into the wild,' the official said. 'Zeenat, even during her stay in a large enclosure, showed signs of estrus towards a wild male tiger (T12). Taking this opportunity, the tigress was released from the enclosure. Mating with T12 was recorded on thermal cameras installed at Jamuna meadow in the second week of May,' the official said. Since her release, Zeenat has been moving inside the core area of STR and hunting natural prey such as cheetal, sambar and wild boar. 'The tigress is being monitored 24 hours by tracking teams. Each team consists of 4 persons. It is also being monitored using satellite-based GPS,' he said. 'She has stopped mating and has isolated herself — both strong indicators of pregnancy. Given that the gestation period in tigers ranges from 105 to 120 days, we expect Zeenat to give birth by August or early September,' the official said. Zeenat was brought to Similipal from Tadoba-Andhari Tiger Reserve (TATR) in Maharashtra as part of tiger supplementation project. She escaped from STR on December 7 and roamed around three States before being captured in West Bengal's Bankura after 23 days. According to a research by Uma Ramakrishnan of the National Centre for Biological Sciences, Bengaluru, in 2021, the population of tigers inside Similipal is genetically isolated and inbreeding is taking place within the reserve. To counter this trend, it was proposed to translocate tigers from the central Indian landscape to STR, the official added. Although the tiger population in Similipal has been increasing at about 18 per cent annually since 2014, nearly 50 per cent of them display pseudo-melanistic coat colour, indicating high inbreeding, he said.
Time of India
02-07-2025
- Science
- Time of India
Zeenat finding mate raises hopes for genetic diversity in Similipal: Official
1 2 Bhubaneswar: With tigress Zeenat finding a mate in Similipal Tiger Reserve, and Yamuna also settling in the habitat, wildlife officials hope it will go a long way in bringing about genetic diversity in the big cat population. "Both Zeenat and Yamuna almost getting settled in the reserve has marked the beginning of Similipal's journey to welcome genetic variation in big cats. Zeenat was released perfectly during her estrus cycle, during which she goes through hormonal changes, leaving no scope for further dispersal," said chief wildlife warden Prem Kumar Jha. Tiger population in Similipal has been growing at 18% annually since 2014, but 50% of the population is pseudo-melanistic, wildlife officials said. National Centre for Biological Sciences scientist Uma Ramakrishnan during her research in 2021 had suggested that genetic diversity is needed to check pseudo-melanism, a trait of inbreeding, and sustain big cats in Similipal. Ramakrishnan had proposed the translocation of tigers from the central India landscape as the big cat population in Similipal had less genetic diversity. "The findings also identified that the population is isolated, and inbreeding is going on. Therefore, a genetic rescue strategy was required, which is going to become successful now," Jha added. With approval of the National Tiger Conservation Authority (NTCA), Tadoba-Andhari Tiger Reserve was chosen to select tigresses for translocation. Tigress Yamuna was identified in TATR as T-158 (S3), and Zeenat was known as T-163 (S1). In Feb, state govt released its own tiger estimation report that pegged Similipal's big cat population at 27. Of these, 24 were caught on camera trap, and it was found there are 10 males and 14 females. Zeenat was captured on Dec 29 last year in West Bengal after she dispersed and was released back into a soft enclosure on Jan 1. "On showing signs of estrus, male T-12 was attracted near Zeenat's enclosure. Taking the opportunity, she was finally released into the wild on April 17," Jha further said. Wildlife officials said that while they have video evidence of Zeenat getting a partner, they are yet to get any evidence of Yamuna finding a mate, although she has settled in the Similipal biosphere region under Kuldhia Wildlife Sanctuary. Yamuna was released in Similipal's South division. Zeenat was first released in the north, and in south the second time. Zeenat is being monitored round-the-clock by multiple tracking teams in eight-hour shifts, with each team having four personnel. "Monitoring is being done by walkie-talkies continuously as well as through satellite-based GPS location obtained every four hours," an official said. Former PCCF (wildlife), Susanta Nanda, during whose tenure the translocation started, said the revival of Similipal landscape and tiger population is now on the right track.
