Himalayan newt: A concern in celebrating 25 years of Biodiversity Day

Rahul Ashem *

Himalayan newt :: Pix - TSE

Himalayan newts are lizard-like structure, with slender bodies, blunt snouts, short limbs and blackish brown in color. The conservation status of Himalayan newt is not systematically investigated but listed under the endangered category of the Wildlife Protection Act of 1972.

"Celebrating 25 Years of Action for Biodiversity" is the theme for 2018 International Day for Biological Diversity (IDB). The 25th year marks the anniversary of the entry into force of the Convention on Biological Diversity (CBD) and highlights progress made in the achievement of its objectives at the national and global levels.

Despite mounting efforts over the past years, the decline of biological diversity from habitat destruction, fragmentation, over-harvesting, pollution, climate variability and change is still a problem. Presently, the population status of Himalayan newts at Zaimeng Lake, Kangpokpi District is an issue of concern. The landscape of Zaimeng Lake is facing various conservation pressures including interference from outside the Lake and human activities on the fringes.

The activities include forest destruction, grazing by livestock, collection of non-timber forest products (NTFP) including Laiwa (Arundinaria callosa) and Loklei (Hedychium ronarium) and sometimes, unregulated investigation on amphibians.

Habitat fragmentation and transformation of natural habitats are aggravated by landslides, soil erosion, shifting cultivation, deforestation, agricultural extension, and forest fires. Corridor areas are highly fragmented because of deforestation practices, overgrazing and overexploitation of forest resources such as collection of fruits like Heikru (Phyllanthus emblica) and medicinal plants (Paris polyphylla).

Out of the living salamanders, Himalayan newt is the most primitive species distributed in this era. In India, the amphibian is the only representative of the order Caudata. The order, Caudata represents a group of amphibians containing the salamanders (Urodela) and all extinct species of salamander like amphibians more closely related to salamanders than to frogs.

Most newts have webbed feet and a paddle-like tail, which make them easier to live in the water. Basically, all newts are salamanders, but all salamanders are not newts. When juvenile, newts live a semi-aquatic to aquatic life, while adult salamanders live a mostly terrestrial life except when they're breeding and laying eggs. Salamander are differentiated from other amphibians (frogs and caecilians) by the presence of a tail in all larvae, juveniles and adults, and by having limbs set at right angles to the body with forelimbs and hind limbs of approximately equal size.

The scientific name of Himalayan newt is Tylototriton verrucosus belonging to subfamily called Pleurodelinae of the family Salamandridae.The species mostly feed on spiders, worms, aquatic species and a range of insects. It is reported that the amphibian produce loud vocalization which is yet to be recorded so far in other species of Tylototriton family.

Studies revealed that most of the Himalayan newt habitats are disappearing at a rapid rate and recommended raising the International Union for Conservation of Nature and Natural resources (IUCN) status of the species to Critically Endangered because of a reduction in the number of populations' density.

Many authors suggests that populations in fragmented ecosystems are more likely to become extinct due to effects associated with smaller size of remnant habitat, greater isolation from neighbouring populations and increased amounts of 'edge' habitat and this should consequently lead to an overall reduction in biological diversity in the region. In fact, the fragmentation of natural habitats is indeed the greatest single threat to the global bio-diversity. Currently, the Himalayan newt is distributed in the State of Manipur, West Bengal, Arunachal Pradesh, Sikkim and Meghalaya.

The celebration of International Day for Biological Diversity (IDB) is to raise awareness and appreciation of biological diversity, the variety of life on earth. The conservation of biodiversity is contingent on maintaining the interconnectedness of the various types of ecosystems found in the surrounding region.

The step forward to conservation of biological diversity is to stop the degradation of the natural environment and to build a future in which humans live in harmony with nature, ensuring that the use of renewable natural resources is sustainable and promoting the reduction of pollution and wasteful consumption. Despite the shrinkage in population of many species and extinction of some of them, majority of the biodiversity are still available in Manipur.

It is therefore, necessary to know them and understand their biology and economic potential and conserve them for the well being of the humanity at large. Losing biodiversity reduces the productivity of ecosystem goods and services from which we constantly draw; lowers resistance to environmental changes and increase variability in certain ecosystem processes such as plant productivity, water use, and pest cycles. Therefore, the time is to take up measures for conservation and protection of biological diversity and sustainable management which is fundamental to sustainable development.

The conservation of locally endemic species like Himalayan newt can be one of the greatest endeavours to support the celebrations on this important day. The amphibian is only distributed in the high altitude region of Eastern Himalayas. The conservation status and threats of Himalayan newt is yet to be intensely evaluated and thus information on their population trend and assessment is quite inadequate.

Therefore, it is vital to conserve existing forest remnants, which may harbour relic populations of local endemics. Recent survey on Zaimeng Lake indicates the presence of Himalayan newt as near threatened species due to environmental degradation and change. It is possible that high altitude forests are highly vulnerable to habitat fragmentation because of greater species richness, patchy distributions and presence of rare species with small populations.

Habitat specialists and species with coevolved interdependencies such as plant-pollinators, host-parasite is particularly vulnerable to fragmentation. Some forest vertebrates avoid even small clearings and thus their population may become fragmented by narrow linear barriers such as kaccha roads. Linear clearings also facilitate invasions of non-forest species. A fragment from landscape is often not self-sustainable and requires restoration efforts to maintain the ecological function and bio diversity.

Recommendations for long term conservation plans include collecting data on population reduction and extent of occurrence not only in the generally observed areas of Kangpokpi, Ukhrul and Senapati districts but also in other districts of the State.

Ecotourism, controlled trekking, bird watching and so on can be planned through local initiatives so that the conservation issues are understood and acted upon at grass roots' level. Improvement in the living standards of the local people will also reduce pressure on the local natural resources, including wildlife.