Birds in Farming: Balancing Ecosystem Services and Crop Protection for Sustainable Agriculture

Birds have both positive and negative impacts on farming. And they are given in below table

Some of the birds commonly found in nature and their role

Considering above parameters one by one:

Are birds really competitor or mutualism living organisms: When we consider the birds as our competitors for food, we need to understand that they are also part of biological cycle, we need to follow a live and let live policy. But how to achieve this. For this we need to see that the plants that are required in small quantities by us human beings, and are most liked by birds for their food and shelter shall be available in the area like farm or entire village .

let’s try understanding with some statistics.

The average food intake by birds in the natural environment depends heavily on their species, size, metabolism, diet type, and activity level. Birds have very high metabolic rates, so they generally eat a large amount relative to their body weight, especially small birds.

Here is list of some commonly used plants for feeding by birds

These Plants provide energy rich seeds and fruits , especially important in fall and winter Nectar plants support humming birds and other nectar feeders . Many of these wild plants grow naturally on farm edges, field margins, or fallow land, providing vital food and shelter. Also these plants would be fodder for our livestock like sheep, goat, cows, buffaloes etc. and some may be harvested and used for poultry feed also.

So we need to understand the number of birds feeding on grains, insects, dead bodies, other birds etc. Among this, grain eating birds what is the consumption quantity by that category of birds. And next is what are those grains, fruits etc which we may not consume and the birds consume so that those plants we need not kill. And all this needs a community based decision and for this awareness is most needed than legal things.

Fruit damage: if we all remember in our childhood we used to eat birds pecked fruits, especially mango assuming they will be sweet. Those were the days when we used to cultivate for self, distribute among our friends and relatives and for our workers. And if selling it was almost direct selling and people were also knowing the causes of damage. But now with large companies coming into marketing, rising quality consciousness (good or bad) is forcing us to have a good sized, shaped, unharmed fruits. So birds are considered to be enemies of fruit crops and farmers. Considering the good that birds do and ill effects of chemicals that we are using today we need to see birds for our benefit.

The other issue in farming is wild boar problem: In recent days problem of wild boar is very serious in farm, and here comes the role of large birds, large birds like eagles and hawks may prey on very young piglets and may help in reducing pig population.

Weed Management: Birds are part of an integrated weed management system where birds consume the seeds of weed plants and help control weeds. This reduces the cost of cultivation as spending on herbicides is reduced. Some examples would like granivorous (seed eating) birds like sparrows, finches, pigeons, and doves, consume weed seeds. By eating these seeds before they germinate, birds reduce the weed seed bank in the soil, lowering future weed growth. Also while eating weed seed grains the birds disturb the soil, it acts like tilling the soil. This again has a positive impact on soil and crop yield.

Examples of Birds Helping Weed Control

Sound as Growth promoter: Some time the sound of predator birds like hawks, owls will reduce pest birds like sparrows, pigeons, crows. And some study shows that 50% reduction in bird damage when predator calls are used strategically. This is one way the other way how sound of birds influence crop yield, as the sound acts as motivational music, support the plant growth. And we could see some farmers adopting speakers in farm for the crops.

Birds against Rodents: Owls and raptors hunt rodents that damage crops or spread diseases. This is an indirect method to increasing the yield. We struggle to protect many fruit plants, grains even in storage also to avoid rodents. But birds would be best option to manage them. These rodents would be feeding on some other insects, weed seeds etc which again would help to increase the yield.

Bird’s excreta as manure: Majority of farmers use chemical fertilizers believing that it only increases the yield; never try to understand the ill effects of it. But in recent times because of many reasons at least some tried to understand the ill effects of chemical fertilizers and started organic farming.

Here at this point of time when understanding role of birds in farming we need to understand the role of chemical fertilizers so that we all get a clear picture of role of birds in farming.

Chemical fertilizers are said to increase the yield and we need to understand the increase in yield is by 30% to 70% compared to unfertilized fields, depending on nutrient deficiencies.

If we look crop wise

In Cereal crops (wheat, rice, maize): Yield increases of 50% to 100% .

In Vegetables and fruits: Yield improvements of 20% to 80%, depending on crop and nutrient needs.

But this increase is considering the soil quality. More increase in yield in poor soils and less increase in fertile soils. This increase also varies with water availability: Fertilizers are more effective with adequate irrigation. This also depends on crop variety: Some high yield varieties respond better.

So this increase comes when all is normal. And any environmental issues the crop fails, fertilizers will not protect crop and farmer has made expenditure which goes in vain. And this also follows Diminishing Returns & Environmental Concerns: Beyond optimal rates, more fertilizer does not increase yield and can harm soil and environment.

Consider the nutrient content in bird’s excreta as shown below we can understand that these can be made available to plants at free of cost. And this is a sustainable means, healthy means (healthy to plants, healthy to animals that feed on these plants, healthy to us human beings and healthy to environment also) to provide nutrients to plant. If we quantify and compare with prices of chemical fertilizers we will realise role of birds in farming to provide nutrients and increase the yield.

These bird excreta when composted well, it can be still better organic fertilizer. It contains both harmful and beneficial microorganisms. And many a time’s benefits are more than harms. Benefits include improve soil health by adding nutrients.

These good amounts of nutrients and microorganisms improve the soil fertility and reduce the need for chemical fertilizers and pesticides.

Hence as a farmer we need to see that birds live on their food living us our food. And to avoid birds if we cut these plants, we end up in huge loss and face many problems that we are witnessing today.

How Birds Help Improve Crop Varieties: We spend lot of amount and energy on improving crop verities by means of hybridization, GM crops etc. at same time we all fail or forget to understand that the plants themselves develop resistance to insects, diseases, weather changes etc.

When mosquito’s can develop resistance to mosquito repellent, plants can develop resistance to pesticides why can’t crops develop resistance to these diseases and insects.

And for all these to happen there should be natural pollination and in that case birds will also help in natural pollination along with many insects like honey bees, butterflies etc.

Birds help in varietal improvement by Seed Dispersal and Genetic Diversity, this promotes gene flow between plant populations, which can lead to new, genetically diverse plants. Some bird species (like hummingbirds, sunbirds, honeyeaters) act as pollinators. Here Natural Selection & Evolution happens there by improving the quality of plant output. This natural selection and dispersion of seeds help us to Maintain Wild Relatives of Crops which are very crucial in genetic improvement which otherwise is a costly affair.

With all these benefits we need to have birds in ecosystem for better crop yield and life but some of our activities are killing these birds like use of Chemical Fertilizers, Pesticides, and Herbicides.

See this chain: Overuse can lead to nutrient runoff → water pollution → reduction in aquatic insects and plants → decline in insect eating birds and birds feeding on small birds also.

This will help in increasing grain eating birds and later we without understanding this root problem we start controlling grain and insect eating birds which again will be reason for disturbing biological cycle. Increase in insect pests, reduction in availability of plant nutrients which otherwise would have been made available by these birds excreta.

Contamination of water with these fertilizers, insecticide etc harms aquatic ecosystems vital for some bird species. Spray of herbicide will kill weeds which otherwise would have been food for birds and this reduces bird population.

Because of all above reasons birds population has to be optimum in every village, We need to understand The “right” number of birds in an environment —often called the carrying capacity —depends on many factors and varies greatly by ecosystem. And it is the responsibility of every citizen of their area o understand this, so that he can act accordingly.

Then what Determines the “Right” Bird Population?

We should see that bird population will be optimum. Because higher population leads to competition for food with us human beings, and lesser population leads to reduced yield because of increased pest population, lesser manure, increased weed growth and many more reasons.

Taking data from internet we observe that small villages have 500-2000 birds and it varies upto some thousands of birds per village like 10-15 thousand.

So when bird population decreases see that the predator population is controlled, they get place to live and reproduce, and food for consumption. And when the population increases see that their natural enemies are also growing.

For this the decisions have to decentralized and quick enough. And people have to educated on both uses and harms and optimum population of birds in each of the village for a profitable farming.

Here's how to attract and support beneficial birds on your farm:

Provide Shelter / Nesting Spaces, Avoid Chemical Pesticides and Herbicides, Provide a Water Source, Encourage Diversity, Leave Some Crop Residue After Harvest, Create Hedgerows and Shelterbelts, Plant hedgerows around the edges of fields,

If we observe our past worldwide we would come across several well documented examples where the large scale killing or drastic reduction of bird populations led to significant ecological effects. like

1. The Decline of Vultures in South Asia : In the 1990s and early 2000s, millions of vultures across India, Pakistan, and Nepal died rapidly because of poisoning by the veterinary drug diclofenac , which was given to livestock. When vultures fed on treated carcasses, they were fatally poisoned.

This lead to increase in carcass decomposition time, Rise in feral dogs and rats which were reason for spreading diseases like rabies and plague, this lead to increased costs in waste disposal and health care.

2. The Passenger Pigeon Extinction in North America: Once the most numerous bird species in North America, passenger pigeons were hunted extensively in the 19th and early 20th centuries and suffered habitat loss. These Passenger pigeons influenced forest composition by consuming huge amounts of mast (nuts and seeds), affecting regeneration patterns. Their disappearance altered forest dynamics. Some trees may have suffered reduced regeneration without the pigeons’ role.

3. The Effect of Killing Raptors in Europe and North America: Raptors like hawks and owls were persecuted heavily due to fear and hunting in the 19th and early 20th centuries. This increased rodent populations. And without natural predators, rodents like rats and mice proliferated, damaging crops and spreading diseases. Farmers faced more crop damage and disease outbreaks. Later raptor populations recovered due to legal protection, helping control pests naturally.

4. China’s Four Pests Campaign (1958–1962): Part of Mao Zedong’s Great Leap Forward , the Chinese government targeted four pests: rats, flies, mosquitoes, and sparrows. Sparrows were considered a pest because they ate grain. Citizens were mobilized to kill sparrows on mass, by destroying nests, banging pots to keep them flying until they died of exhaustion, and shooting them.

The consequences were Sparrows also fed on insects, particularly locusts. Now locust population increased which devastated crops. This Combined with other policies and natural disasters, this contributed to the Great Chinese Famine, resulting in tens of millions of deaths.

5. Use of DDT and Other Pesticides (Post-WWII Era, Especially 1950s–1970s): DDT was used heavily to kill mosquitoes and agricultural pests. It accumulated in the food chain and caused eggshell thinning in birds. Large-scale bird population declines disrupted ecosystems. the Consequences were Some crop pests flourished in the absence of natural predators. Indirect effects on pollination and pest control. Eventually led to environmental awareness and the banning of DDT in many countries (e.g., the U.S. in 1972), and the resurgence of bird populations.

6. Modern Examples: Scare Tactics & Unintended Effects: In modern agriculture, scare tactics or netting are sometimes used to drive away birds from orchards and fields. In rare cases, if overused or applied broadly: Predator bird populations decline (e.g., hawks driven away). Rodent or insect pests increase, since birds are natural pest controllers. Pollination may suffer if nectar-feeding birds are affected.

These are smaller in scale but reflect ongoing tensions between human agricultural needs and ecosystem health.