During mid-March 2020, academic institutions in Delhi were put under lockdown. A few days later, office work, general discussions, and conversations shifted to online mode. Apart from the pandemic, the conversations were centered around the topic of anxiety and mental stress that may increase due to our current sedentary lifestyle. People are devising new ways to deal with anxiety, and one of them is to interact with nature by undertaking activities such as bird watching, tree watching, gardening, and so on. These activities not only help deal with the stress but also provide an opportunity to learn about the natural dimensions of our urban world.
Even in the densest urban areas, one can easily observe plants and animals. Living in one such locality, this lockdown has provided me the opportunity to notice little things that I had failed to notice before. The first thing that captured my attention was a couple of house sparrows (Passer domesticus) that reside inside a pipe just over my window and which fill our house with their constant chirping. Later, I came to know that the nest was being occupied by sparrows for several years now, although, for some reason, I did not notice them before.
My research domain is vegetation ecology and plants have always intrigued me. Although birds have interested me, I haven’t engaged with them with the same enthusiasm as plants. However, this daily interaction during the lockdown made me quite intrigued to learn more about the winged creatures that are part of our urban life. This article is the story of these little birds and has two parts: one, where for several years it was reported to be declining from all over the world, and two, where it was reportedly said to have bounced back.
It is known that house sparrows have been accompanying humans for almost 10,000 years now (Sætre,et. al 2012). Belonging to the genus Passer and species domesticus, it is known to reside alongside human habitat. They are genetically adapted to digest starch-rich food, an adaptation that also exists in humans (Schembri, 2018). These are omnivorous creatures and can feed on a variety of food such as grains, fruit buds, nectar, and insects. It is a species of least concern as per the IUCN red list and is native to the Mediterranean region, Europe and Asia.
Sparrows in the Spotlight
In the last two decades, these little brown winged birds have become the face of bird conservation, especially in urban areas. The house sparrow was made the state bird of the National Capital in 2012 to support conservation of birds in Delhi. In 2013, the Bihar government also announced the house sparrow as the State bird. All of this happened at a time when there was a lot of news surrounding the declining population of house sparrows in urban areas. A quick search revealed that after the year 2000, there was a rise in research on Passer domesticus (see above figure). Post 2005, newspapers and magazines were flooded with the reports of house sparrows becoming a rare sight in cities (TOI, The Sydney Morning Hearld, BBC, DH) .
In many countries, house sparrows were used to be considered pests as they raided agricultural fields and were known sources of ectoparasites. Many people despised them due to their littering for nest material and fecal droppings. What then caused a sudden shift in attitude towards these birds, so much so that they became the face of urban bird conservation?
It is the sense of rarity or losing one of the most common species that may have put this bird in the international spotlight. Reports from London and Netherlands highlighted that the population of this species went down by more than 50 percent. In both these countries, the house sparrow is in the red list of endangered species (Summers-Smith 2003). Further, in England, population declines were reported not only in the urban but also in rural areas (Hole, et. al 2002). Berlin, Spain, and Brussels all reported similar patterns of population decline. In India, similar cases of the population decline of house sparrows were reported from the states of Andhra Pradesh, Kerala, Rajasthan, and Karnataka state (Kumar et al., 2018).
Why the Decline?
Research from London pointed out avian malaria as the probable cause for the decline (Dadam, et al., 2019). From England, the intensive agricultural practices and lack of winter food were proving to be detrimental (Hole, et al.,2002). In Delhi, one research found that house sparrows are more predominant in the agricultural landscape, indicating their inhabitability of high-density urban areas (Khera, et. al 2009). From the Indian context, three theories were prominent that have been proposed for the decline. First, increasing concretization led to a decline in insect diversity which is necessary as a diet for sparrow chicks. Second, the lack of nesting sites and third, the negative effect of radiation from mobile towers. In 2002 IUCN also listed house sparrow as an endangered species highlighting the declining population of a once-common species. Despite so much research, the exact reason for its decline remained unanswered. However, all this research and conservation initiatives raised an important question: are cities becoming inhabitable for non-human creatures?
Despite worrying declines in sparrow numbers, in the last three years, there have been several reports of this species making a comeback. In 2018, British Trust for Ornithology in its press release announced that contrary to the report of the worldwide decrease in the population, in Scotland, the population of these little birds has increased by 50 percent. In 2018, the IUCN also moved the house sparrow from the red list to the list of species of least concern. In the last two years, there have been several reports suggesting an increase in the number of house sparrows (DTE, TOI, The Hindu, The Guardian). Similarly, a recent study – “State of India’s Birds 2020” – based on long-term data revealed that the population of House sparrow remains stable from the last 25 years in India. However, this study also reported a “gradual decline” in all six major cities (Bengaluru, Chennai, Delhi, Hyderabad, Kolkata, and Mumbai) of India. While news reports are hailing it as a positive sign, I still find it concerning that despite a decade of conservation efforts and awareness campaigns, it continues to show a gradually declining trend in urban areas. We need to have a long-term monitoring program in place to monitor non-humans in cities. We also need to raise awareness not only towards the non-human creatures who have equal rights to the city but also towards designing more animal-friendly cities rather than a concrete jungle that will eventually suffocate us as well.
Dadam, D., Robinson, R. A., Clements, A., Peach, W. J., Bennett, M., Rowcliffe, J. M., & Cunningham, A. A. (2019). Avian malaria-mediated population decline of a widespread iconic bird species. Royal Society open science, 6(7).
Hole, D. G., Whittingham, M. J., Bradbury, R. B., Anderson, G. Q., Lee, P. L., Wilson, J. D., & Krebs, J. R. (2002). Widespread local house-sparrow extinctions. Nature, 418(6901), 931-932.
Khera, N., Das, A., Srivasatava, S., & Jain, S. (2010). Habitat-wise distribution of the House Sparrow (Passer domesticus) in Delhi, India. Urban ecosystems, 13(1), 147-154.
Kumar, A., Kanaujia, A., Kushwaha, S., & Kumar, A. (2018). Nopr.niscair.res.in. Retrieved 21 March 2018, from http://nopr.niscair.res.in/bitstream/123456789/31649/1/SR%2052%286%29%2014-19.pdf
Sætre, G. P., Riyahi, S., Aliabadian, M., Hermansen, J. S., Hogner, S., Olsson, U., … & Elgvin, T. O. (2012). Single origin of human commensalism in the house sparrow. Journal of evolutionary biology, 25(4), 788-796.
Schembri, F. (2018, August). How the house sparrow made its home with humans. Science. doi:10.1126/science.aav2132
Summers-Smith JD (2003) The decline of the House Sparrow: a review. Brit Birds 96:439–446