Has the sparrow population dropped in Sri Lanka due to Climate Change 

Living in Sri Lanka, we have heard many stories about sparrows from our parents or elders. A few decades back, we used to enjoy the sight of sparrows flocking around our houses and listening to their tunes. However, with time these chirps have diminished, and now there is only a handful of sparrows to be seen. This article is a brief study into why the sparrow populations has declined in Sri Lanka. 

Sparrows are among the most widely distributed birds in the world. They are commonly called “songbirds” or “perching birds.” It is also perhaps the species most associated with urban and rural human dwellings. Sparroes are a small omnipresent bird native to Europe. 

Sparrows are relatively small in size. Some eat insects but are mainly seed-eaters, and their cone-shaped bills make them experts at husking seeds. This makes them very adaptable, which is why they are found in most places. More on these birds here. Archived.

There are more than 50 different species of sparrows found around the world. Sparrow are social creatures typically flocking, they are found in pairs or family groups during the breeding season. 

What benefits do sparrows bring to the Environment? 

The Common House Sparrow, the most abundant bird in the world, was regarded a nuisance and a threat to agriculture. However, with research it was found to be a species useful to the environment. Sparrows are known to clean up around human habitats by eating insect pests. 

It was evident that sparrows can dramatically decrease the number of insects, particularly mosquitoes. In addition, scientists have found that sparrows can spread seeds up to 15 times farther from the feeding location. This way, they help in new habitats for other species to thrive in. 

These birds are capable of improving ecosystems which benefits all of us. Even though sparrows are small birds of size of about 12 to 14 centimeters in size, they are a good food source for raptors, larger birds and mammals. Sparrows are a diet for some species of raptors, eagles, owls, hawks, and falcons, and contain about 13% protein on average. In other words, sparrows are just playing a very significant role in food chains. 

Sparrows are a good bioindicator and suggests that the environment is heathy. The psychologists believe that their constant chirping every morning before sunrise also symbolizes that there’s another day coming, which means more opportunities to grow and learn new things. The common house sparrow has long been seen as a harmless irritant that does not provide any real value to humans. However, this small bird actually provides many important services, including insect control and environmental cleanup. More on this here. Archived.

Sri Lankan-based Sparrows

Sri Lanka is a tropical Island which is a biodiversity hotspot. Accordingly, the bird life in Sri Lanka is big for its proportion, 492 species have been recorded of which 219 are breeding residents. The bird life is devided into resident birds and migarotry species who arrive during winter to escape their northern breeding grounds. Among sparrows Sri Lanka commonly has house sparrows. 

Common breeding resident inhabiting close to the human habitations throughout the country. It feeds in flocks on seeds, insects and food wastes around human dwellings. House Sparrow breeds throughout the year and nest is a mass of grass, straws, etc. line with feathers and place in a cavity in a building. 

   Fig 01. House sparrow

House sparrows prefer domesticated environments, which includes residential, and urban areas and farms. They are not commonly found in uninhabited woodlands, deserts, forests, and grasslands. Its predators include domestic cats, hawks, owls, and many other predatory birds and mammals. House Sparrows are monogamously pair for each breeding season. February and May are the popular nesting period. You can commonly find house sparrow nests in crevices of buildings and trees. Dried vegetation, feathers, strings, and paper are used to build nests. One to eight eggs can be present in a clutch, with the possiblity of four clutches per nesting season. Incubation begins after all the eggs have been layed. Both males and females participate in incubation for short periods of a few minutes each. Incubation lasts for 10 to 14 days. After the eggs are hatched, both males and females feed the young through regurgitation. 

How climate change affects sparrows

Generally, bird populations are under threat globally. While many factors contribute to this from habitat loss to pesticides, outdoor cats, and window collisions. It is obvious that climate change is an important driver behind this worrying trend. Warming temperatures are changing where birds live, the timing of their migration patterns and egg laying, and even the sizes and shapes of their bodies. Birds are shrinking, and the culprit appears to be rising temperatures. Nestlings that mature during hot summers grow into smaller adults, and they stay that way even if the birds also live through cold winters. Scientists now suspect that exposure to excessive heat is a stronger influence on body size than bitter cold, a finding that raises worrisome implications about the health of birds on a warming planet. Here. Archived

Moreover, variation in body size is linked directly or indirectly to animals adapting to different climates, then body size could be useful for monitoring the extent to which sparrows’ populations are capable of adapting rapidly to changing climates. The marsh sparrows will face danger due to sea level rising. That sea level rise is going to keep on increasing for the next few decades, so with the rising sea level, the frequency with which nests are likely to flood is going up and that means the birds face a very uncertain future.

These house sparrows live more in human settlements and are affected by pollution and toxic gases found in cities. A team of  researchers found that urban sparrows suffered higher levels of free-radical damage in comparison to rural birds. 

                                  Fig 02. The city Sparrows 

In addition, the blood samples revealed that city-dwelling sparrows were trying to fight off these damaging molecules but, in comparison to their rural counterparts, their natural defenses had a lower capacity to do so. Also house sparrows living in the city are suffering from more stress than those living in the countryside, this to differences in air quality and diet. Here. Archived 

Apart from the direct effects that living in a warming world have on their lives and bodies, birds also face a tangled web of indirect effects as the ecosystems in which they live are increasingly disrupted. Here. Archived 

Does Signal Tower Radiation Affect Sparrows?

There is no immediate impact on sparrows when exposed to mobile radiation so far based on the records, but it’s a slow killer and reports have suggested to see mobile radiation as a pollutant to not just birds and other animals, but also detrimental to humans. 

Electromagnetic fields and radiation that are invisible to human eye are found almost everywhere. Several natural and anthropogenic sources generate electromagnetic fields in the surrounding air. For example, television towers, radio towers and cell phone towers. It must be noted here that the radios/televisions transmit a weak radiofrequency. But the cellular phones and the mobile base stations transmit a much stronger electromagnetic field. Mobile phones have become a necessary tool in for almost everyone in the world. Several countries claim to have observed a reduction in bird diversity coinciding with the Cellular Mobile Base stations.

The most prominent example of this impact comes from the UK where a huge decline in several species of urban birds was observed, including the sparrows. The sparrow population in the country declined from 24 million to 14 million birds within 30 years. An abrupt decline of 75% occurred between 1994 and 2002 that coincided with the rollout of mobile technology in the country.

This mainly impacts the reproductive success of birds. The hatching success is reduced in the birds though the fertility and fledging success is increased. Here. Archived.

However, it is noteworthy that no such cases or results have been reported in Sri Lanka. And there are various scientific and logical disagreements among scientists on this issue globally.

Cellular phones are essential for our lives. However, the extensive usage and upgraded services of mobiles continue to threaten the diversity and the lives of different birds. While the cellular phones cannot be completely wiped from our lives, it is important to find an alternative technology that can keep the wireless communication strong but do not pose any risk to the lives of these little creatures around us.

In a nutshell, increased exposure to electromagnetic field and radiations in the surrounding air support a decline in the population of sparrows. In addition, the impact of other factors like urbanization, climate change, global warming, habitat loss and environmental pollutants cannot be completely neglected.

Is the sparrow an endangered bird in Sri Lanka?

The conservation status of sparrows is listed as least concerned on the IUCN Red List. It is extensively, and usually unsuccessfully, persecuted as an agricultural pest. It has also often been kept as a pet, as well as being a food item and a symbol of lust, sexual potency, commonness, and vulgarity. Though it is widespread and abundant, its numbers have declined in some areas.

Legal protection in Sri Lanka

The real reasons for the decline and disappearance of the House Sparrow from many areas of Sri Lanka has yet to be ascertained and we can only presume some possible causes and continue with the observations as was in the past to see whether the causes can be definitely found out. It is also seen that there are slight recoveries in some areas like Nuwara Eliya since 2008, but is still too early to predict whether this trend will continue in the future or spread to other areas as well. In these circumstances, the move to make the House Sparrow a protected species of birds is praiseworthy, as it show that the authorities are aware of and are sensitive to the decline of this much liked and familiar bird. This happened with the amending of the Fauna and Flora Protection Ordinance in 2009, implementing a decision taken by the Ministry of Environment in 2008. According to the provisions of Section 31 of the Fauna and Flora Protection Ordinance (as amended by Act No. 22 of 2009).

Eco friendly nest (Home) will be established at various places, it would be safe and convenient for Sparrow Bird to make her nest (Home) there. Along with this her egg and Sparrow Bird Baby will be safe from other attacker birds. People will be made aware to protect and conserve them through this campaign and extinct species would be saved in the future.

Most of the countries ensure that sparrow protection plans as well. Countries like India process more projects for protecting sparrows.

Each year March 20th is celebrated as the World Sparrow Day and rightly so, as these birds deserve sincere conservation efforts because they have been displaced from their genuine habitats due to anthropogenic intervention. Climate change, Modern technology-based outdoor equipment coupled with rising pollution levels has disturbed the ambient living conditions of these birds in our cities. The house sparrow plays a vital role in balancing the ecological biodiversity of a city where the flora and fauna survive due to the complimentary role played by each one of them. The extinction of an entire species is bound to create an imbalance that can damage nature’s setting and eventually harm human survival, too, as we also are a part of nature.

-With Inputs from Dinesh Balasri –If you have any queries or come across suspicious content related to climate change or the environment and want us to verify them for you, then send them to us on our WhatsApp hotline: +917045366366