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bioRxiv · 10.1101/2020.12.15.422890

Ruling the Roost: Avian Species Reclaim Urban Habitat During India's COVID Lockdown

Madhok, R.·Gulati, S.
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Abstract

As we retreated to our dwellings in the "anthropause" of spring 2020, did other species return to our urban centres? We leverage an increase in balcony birdwatching, a million eBird entries, and difference-in-difference techniques to test if avian species richness rose during Indias COVID lockdown. We find that birdwatchers in Indias 20 most populous cities observed 8-17% more species during the lockdown. Most additional observations occurred after a two-week lag, signaling greater abundance instead of improved detection. More frequent appearances of at-risk, rare, and common species were recorded, implying that making our cities more wildlife friendly can protect threatened species in addition to urban specialists. Our contributions are: 1) to isolate and estimate a causal impact of reducing human activity on avian diversity, 2) to improve the external validity of this literature in rapidly urbanizing bio-diverse developing countries, and, 3) to illustrate a method separating abundance from detection in observational avian surveys.

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Madhok, R., Gulati, S.. 2020-12-16. Ruling the Roost: Avian Species Reclaim Urban Habitat During India's COVID Lockdown. https://doi.org/10.1101/2020.12.15.422890

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