SREL Reprint #3631

Anthropogenic disturbance favours generalist over specialist parasites in bird communities: Implications for risk of disease emergence

Guha Dharmarajan1,2, Pooja Gupta1,2, C. K. Vishnudas3, and V. V. Robin3

1Savannah River Ecology Laboratory, University of Georgia, Aiken, SC, USA
2Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal, India
3Indian Institute of Science Education and Research Tirupati, Tirupati, Andhra Pradesh, India

Abstract: Niche theory predicts specialists which will be more sensitive to environmental perturbation compared to generalists, a hypothesis receiving broad support in free-living species. Based on their niche breadth, parasites can also be classified as specialists and generalists, with specialists infecting only a few and generalists a diverse array of host species. Here, using avian haemosporidian parasites infecting wild bird populations inhabiting the Western Ghats, India as a model system, we elucidate how climate, habitat and human disturbance affects parasite prevalence both directly and indirectly via their effects on host diversity. Our data demonstrate that anthropogenic disturbance acts to reduce the prevalence of specialist parasite lineages, while increasing that of generalist lineages. Thus, as in free-living species, disturbance favours parasite communities dominated by generalist versus specialist species. Because generalist parasites are more likely to cause emerging infectious diseases, such biotic homogenisation of parasite communities could increase disease emergence risk in the Anthropocene.

Keywords: amplification effect, avian, dilution effect, disease ecology, emerging infectious disease, epidemiology, Haemosporidian, infection dynamics, pathogen, vector-borne disease

SREL Reprint #3631

Dharmarajan, G., P. Gupta, C. K. Vishnudas, and V. V. Robin. 2021. Anthropogenic disturbance favours generalist over specialist parasites in bird communities: Implications for risk of disease emergence. Ecology Letters 24(9): 1859-1868.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).