A new study has documented the extent of plastic ingestion as an emerging threat to endangered Asian Elephants in Uttarakhand. The researchers say that the tuskers are ingesting large amounts of human-generated waste, including plastic of varied sizes that are released through their dung, affecting other species and the environment.
Researchers from the Jawaharlal Nehru University, the Nature Science Initiative and the Wildlife Conservation Society – India, have highlighted plastic waste as an emerging threat to the health and population of Asian elephants.
The study published in the Journal for Nature Conservation, researchers systematically documented the presence of human-generated waste in elephant dung in and around the forested landscapes of the state of Uttarakhand. Elephants in this landscape range in close proximity to human habitations and reportedly visit garbage dumps that have been accumulating around the forest edges.
The researchers allude to the increasing fragmentation of forests that leads elephants to venture into human settlements to feed on cultivated crops. They end up foraging around garbage dumps carrying food waste, unable to segregate organic and inorganic waste in the process. Asian elephants rely primarily on wild grasses, fruits, roots, and tree bark for food.
Researchers examined the diet of Asian elephants through dung samples from the edges and interiors of forested landscapes.
Hazardous waste in elephant dung
The study has, for the first time, scientifically confirmed the presence of a large amount of plastic, alongside other human-generated waste in the diet of Asian elephants. A large proportion of hazardous waste found in the dung of the elephants was made of items like plastic cutlery, food containers, polythene bags, tetra packs as well as glass, metal wires, rubber bands, clay pottery and pieces of tile. The dominance of plastic in their diet implies the continued widespread use of plastic and the lack of waste management, the researchers point out.
The researchers say in their published paper, “We quantified plastic particles and other anthropogenic waste from elephant dung samples collected from edges and interiors of forest areas, confirming plastic ingestion by this endangered mammal species. Each human-derived item was identified, measured, and sub-categorized into plastic or other anthropogenic waste.”
They further say, “About one-third (32 per cent) of the elephant dung samples showed presence of anthropogenic waste.”
The plastic particles the research team recovered from the dung of the giant mammals ranged from one to 355 mm and comprised of 85 per cent of the waste recovered from elephant dung samples.
“Ingested plastic may leach toxic chemicals such as phthalates in elephant gut and may affect their reproductive system with potential impacts on their survival rates and population size” says Gitanjali Katlam, ecologist and the lead author of the study from Jawaharlal Nehru University.
Solid waste management
The study also found that the dung sampled inside the forest contained double the amount of plastic particles compared to the dung found on forest edges. This finding indicates that the elephants carry plastic particles far into the forest, increasing the chances of the plastic entering the food chain through other species that consume elephant dung.
“High plastic presence in elephant dung highlights its widespread use near protected habitats and lack of waste segregation practices underlining the vulnerability of wild animals to plastic ingestion risk,” the researchers say in their published paper.
The effects of plastic pollution on marine ecosystems and animals have been widely documented. However, this study also throws light onto the understudied aspect of the impact of plastic pollution on terrestrial animals.
The IUCN Red List categorizes the Asian elephant as ‘endangered’ and is under immense pressure due to habitat degradation, loss and fragmentation, persecution by people, and deaths due to accidents. This study establishes plastic pollution as a novel threat to our terrestrial megafauna and forest ecosystems.
“Human habitations around natural habitats need comprehensive solid waste management strategies to address this problem” says Dr. Anant Pande, co-author and program head at WCS-India, suggesting a strategy that involves segregation at source, mapping of garbage dumps and assessment of risk to wildlife and mass awareness campaigns to educate the public on the perils of plastic pollution.
Image: Wikimedia: Tharmapalan Tilaxan