Plastic waste reshaping bird nesting behaviour at Jahangirnagar University

Human settlement and urbanisation are reshaping how common mynas build their nests, with a Jahangirnagar University study finding substantial use of plastic and other human-made waste. The closer nests were to roads, residential buildings and dumping sites, the greater the share of such materials – and higher use was linked to lower hatching success. 

The study, titled "Nesting in a Human-Dominated Environment: Quantifying Anthropogenic Materials in the Nests of Common Myna (Acridotheres tristis)," was conducted by Zoology Department Assistant Professors Ashis Kumar Dutta and Faisal Mahmud from January 2025 to April 2026.

Researchers installed 96 pairs of artificial nest boxes with two entrance sizes and identified eight types of human-made materials in the nests. 

Packaging and wrapping materials topped the list, found in 71% of nests, followed by polythene at 61%. Thread or rope accounted for 27%, metal 21%, cardboard or paper 10%, non-woven fabric 6%, cloth 4% and straw or plastic pieces 2%.

White or colourless materials made up 81.72% of the artificial materials, suggesting the birds may have a preference for certain colours.

The real red flag, however, was the effect on reproduction. An analysis of 40 nests found that artificial materials did not significantly affect the number of eggs, but nests with a higher proportion of such materials had significantly lower hatching success.

"Various types of plastic are often found in common myna nests because the bird has long adapted to human-modified environments," said Dutta. "But the question is – how much plastic is too much? We found alarmingly large amounts of plastic and other human-made waste in myna nests, which is concerning."

He said what the birds are carrying into their nests also offers a glimpse of the campus's wider plastic pollution problem.

Researchers found no significant difference in the amount of human-made material used in nests between boxes with larger and smaller entrances.

Waste system remains dysfunctional

The problem is hard to miss around Jahangirnagar University. Its recycling waste-processing centre at Bish Mile has reportedly been out of action since 2020, while waste is routinely dumped around Bottola, the campus lakes and academic buildings.

Estate officials attributed the centre's inactivity to inadequate waste management and insufficient funding.

The study thus puts a striking twist on the campus waste problem: plastic is not just piling up on the ground – mynas are carrying it home.

Urban and Regional Planning professor Moinuddin said plastic, cloth and other non-biodegradable waste should not be mixed with ordinary garbage. Better infrastructure, he said, will only go so far without changes in public behaviour.

A proposal to revive the recycling centre has been submitted to the state minister for the Ministry of Environment, Forest and Climate Change. The university also plans to divide the campus into zones and deploy teams weekly to clear plastic and polythene, while shops and other stakeholders will be asked to use designated disposal points.

"However, this will take time and requires sustained efforts. Only then can we reduce the impact of human activities on the campus environment and wildlife," he said.