Sparrows and their role in predator-prey interaction in rice ecology

 Ajay Kumar Mishra, Manas Ranjan Sahoo, Sampad Senapaty, and Sheetal Sharma   |  

World Sparrow Day (20 March) celebrates one of the most abundant birds in the world that was once considered a menace to agriculture. However, house sparrows have been recognized as a beneficial species. House sparrows prey on pests of rice, cotton, and corn, controlling their numbers, and reducing crop damage. House sparrow populations can reveal important details about the general well-being and sustainability of the agricultural landscape.

Photo: ISARC

House sparrows (Passer domesticus) are adapted to successfully thrive in a range of habitats including urban and agricultural settings. These social birds frequently congregate in huge groups and graze opportunistically on a range of items, such as seeds, insects, and leftover human food.

Sparrows have a major beneficial role in paddy fields as they prey upon pests that harm rice harvests. By preying on these pests, sparrows help to control their populations and reduce damage to the rice plants. The birds have been observed to eat many rice pests, such as the brown planthopper (Nilaparvata lugens) and the rice leaf folder (Cnaphalocrocis medinalis).

They have been observed to feed on other major agricultural pests such as the larvae of corn earworms (Helicoverpa zea) and cotton bollworms (Helicoverpa armigera).  Their diet also consists of grasshoppers, aphids, and caterpillars that harm crops.

House sparrows are regarded as bioindicators of environmental health and are frequently used as a measure to track the effects of agricultural practices on wildlife populations. They are able to detect changes in the rice fields’ environmental conditions. Their presence or absence may be a reflection of modifications to agricultural, water management, and land use techniques. Keeping an eye on house sparrow populations can reveal important details about the general well-being and sustainability of the agricultural landscape.

Sparrows are also important for their cultural-historical significance. They are considered important cultural symbols because of their associations with human habitation and agricultural ecosystems for millennia. Their close relationship with humans has been reflected in the art, literature, and folklore of many cultures.

Although House sparrows play a beneficial role in paddy fields by assisting pest management, their populations are being heavily impacted by the use of pesticides in fields. Pesticides can reduce the availability of insects for birds to feed on and can also be directly toxic to birds if ingested. Therefore, it is important to balance the use of pesticides with the conservation of bird populations in paddy fields.

Other factors that attribute to the declining in the population of house sparrows in agricultural landscapes include land use, habitat loss and interspecific competitions, pollution, and changes in agriculture practices from conventional to modern farming practices.

Excessive land use has destroyed or altered many natural habitats for house sparrows.  For example, the removal of hedgerows, grasslands, and other open spaces reduces the availability of suitable nesting sites and food sources.

Climate change also affects the timing of breeding and the availability of food sources.

Modern agricultural practices and environments are being polluted with a variety of chemicals, including chemical fertilizers and heavy metals, which can affect the health and reproduction of house sparrows.

It is essential to promote conservation efforts for house sparrows, especially in agricultural ecosystems. Reduced pesticide use, the preservation of natural habitats within agricultural landscapes, and increased public knowledge regarding the value of bird conservation are some actions for conservation efforts.

Photo: ISARC

There are also a number of things to support the maintenance of the house sparrow population in rural and urban areas. These actions can support and even boost the number of house sparrows:

● House sparrows like to make their nests in birdhouses, nesting boxes, or even openings in structures. Placing birdhouses for nesting boxes in gardens provides them a place to breed.

● House Sparrows. being omnivores, eat various seeds, grains, and insects. Bird feeders filled with seeds and grains, leaving parts of farms or gardens in a natural state to attract insects, and making fresh, clean water for drinking and bathing, especially in summer, available provide suitable conditions for birds.

● Using less chemical pesticides in gardens and farms and shifting to more organic pest control techniques would serve the purpose of the conservation of house sparrows.

● Planting native plants counteracts habitat loss and provides house sparrows with a natural food supply.

● Engaging people in citizen science initiatives such as the Great Backyard Bird Count and eBird can assist researchers in tracking long-term trends in bird populations and identifying regions that require conservation measures. These actions would ensure awareness among locals toward the conservation of such species.

Under alternative natural farming systems, the International Rice Research Institute South Asia Regional Centre (ISARC) installed bird perches for integrated pest management in rice-based cropping systems and found different bird species sitting and enjoying the insects as food and reducing pest incidence.

In general, the role of sparrows in rice fields is multifaceted and highlights the interrelationships of ecological and cultural systems. By promoting the conservation of sparrows and other wildlife in agricultural landscapes, we can help ensure the continuation of ecological services and cultural values important to human well-being, as well as we can work towards a more sustainable and integrated approach to agriculture and wildlife conservation.

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