Protected areas (PAs) are the cornerstones of conservation and have been shown to support higher density of conservation-dependent species. The success of PAs has been attributed to their ability to mitigate both forest loss and forest degradation. Effectiveness of PAs is conventionally measured in terms of species diversity; evidence for the consequences of protection on the functional diversity of species assemblages is scarce. We utilized the Kerala Bird Atlas data to quantify alpha diversity, beta diversity, and functional diversity from 300 sites within protected and non-protected forests along the Western Ghats. Of the total forest cover in Kerala, about one-fourth is under protection, the rest constitute reserve forest (RF). We tested if various metrics of biodiversity differ across PAs and adjacent RFs and which metric better captures this difference. Results show that the effectiveness of protection varies across guilds and does not seem to impact overall species richness. PAs are effective at the level of assemblage composition, and support higher abundance of species of conservation-concern. Species diversity did not vary with the protection status. Functional richness was high in PA while functional dispersion was high in RF. The effect of protection was more prominently visible in terms of functional diversity than species diversity. Such empirical data may broaden our understanding of the PAs and assist in monitoring efforts.

This dataset is part of the manuscript which utilized data from the Kerala Bird Atlas. The Kerala Bird Atlas has been described elsewhere (Data set https://doi.org/10.5061/dryad.zpc866t8g ). Additional details on the 361 avian species were obtained from references mentioned below:

● Stewart, P. et al. (2021), Global impacts of climate change on avian functional diversity, Dryad, Dataset, https://doi.org/10.5061/dryad.dfn2z351n
● Wilman, H., Belmaker, J., Simpson, J., de la Rosa, C., Rivadeneira, M. M., & Jetz, W. (2014). EltonTraits 1.0: Species‐level foraging attributes of the world's birds and mammals: Ecological Archives E095‐178. Ecology, 95(7), 2027-2027.
● Bird J.P. , R. Martin, H.R. Akçakaya, J. Gilroy, I.J. Burfield, S.T. Garnett, A. Symes, J. Taylor, Ç.H. Şekercioğlu, S.H. Butchart. Generation lengths of the world’s birds and their implications for extinction risk Conserv. Biol. (2020), 10.1111/cobi.13486
● SoIB, State of India’s Birds, Range, trends and conservation status. The SoIB Partnership. 2020, pp. 50. Available at https://www.stateofindiasbirds.in/
● Pigot, A.L., Sheard, C., Miller, E.T., Bregman T.P., Freeman, B.G., Roll, U., Seddon, N., Trisos, C.H., Weeks, B.C., & Tobias, J.A. 2020. Macroevolutionary convergence connects morphological form to ecological function in birds. Nat Ecol Evol 4, 230–239. https://doi.org/10.1038/s41559-019-1070-4
● Praveen J, Nameer P O, Jha A, et al. Kerala Bird Atlas 2015-2020: features, outcomes and implications of a citizen-science Project. (In press) Current Science.

All Analysis were done in R. R script for the same and input files has been provided.