The nests of house sparrows are kept free of parasitic insects by a lining of leaves from the neem tree, containing insect-repelling compounds.


"During an outbreak of malaria in Calcutta during 1998, Dr. Dushim Sengupta and fellow scientists at Calcutta's Center for Nature Conservation and Human Survival were surprised to witness house sparrows lining their nests with (and also eating) leaves from the paradise flower tree (Caesalpina pulcherrima), a species whose leaves are rich in the anti-malarial drug quinine. Confirming that their choice of leaves was deliberate, the sparrows swiftly gathered fresh leaves of this same species when the scientists removed those already lining their nests. Moreover, before the malaria outbreak, these birds has been using leaves from the neem tree (Azadirachta indica) for nest lining. These contain high concentrations of insect-repellent compounds, which are of great benefit to birds rearing nestlings, who are vulnerable to diseases spread by insects and to nest-dwelling parasitic insects." (Shuker 2001:216-218)

The Hidden Powers of Animals: Uncovering the Secrets of NatureMarshall Editions Ltd.January 1, 1970
Dr. Karl P. N. Shuker

House SparrowPasser domesticusSpecies