After spending many hours on the catwalk at Miner Institute doing cow watch for behavioral research and continually hearing the flapping wings of pigeons, it got me thinking about how much damage birds really cause on a dairy farm.

Dairy farms offer an easy source of food and shelter, especially during the winter months, making them a perfect habitat for large populations of birds. Although small in size, birds can cause a tremendous amount of damage including consumption of feed; contamination of feed, water and bedding; fire hazards and facility damage.

Species such as the European starling, house sparrow and pigeon are some of the most common types of birds found on dairy farms – and therefore cause the most damage. Researchers at Cornell University have estimated starlings alone can cost U.S. agriculture $800 million annually.

Birds generally consume the grain portion of the TMR, which is the more expensive portion of the ration. Not only does this cost the farm money in lost feed, but it can also lead to decreased production from cows, as the diet cows are actually consuming differs from what is formulated for them.

According to the USDA, a flock of 1,000 starlings can consume up to 40 pounds of feed daily, which adds up quickly. The USDA National Wildlife Research Center estimated annual feed losses were over $9,000 for dairies reporting one to 1,000 birds, nearly $23,000 for dairies reporting 1,000 to 10,000 birds and over $64,000 for dairies reporting over 10,000 birds.

This is especially difficult to manage on dairy farms that feed a TMR ad libitum, as grain is always available to the birds. One way Miner Institute has tried to combat grain loss is by storing it in grain bins rather than a commodity shed to eliminate bird access. This can also reduce contamination of the grain with bird feces, helping to reduce the risk of disease transmission.

Eliminating bird nests is another technique used at Miner Institute, as birds will continually return to their nesting sites. Recently, the dairy barn at Miner Institute was pressure-washed, eliminating bird nests. In addition, bird nests are removed on a more regular basis as farm staff walks through the barn.

Birds also pose a biosecurity risk, as they can easily fly between farms carrying micro-organisms that could lead to diseases such as salmonella, E. coli, histoplasmosis, cryptococcosis and avian tuberculosis. These diseases may not only affect the cows but can also affect farm workers who come in contact with bird feces.

Other concerns with birds include fire hazards and damage to facilities. Birds may cause damage to insulation, which can be a costly repair. Further, birds often nest on light fixtures and wiring, which can be a potential cause of fire. Bird nests can even plug drains and gutters.

One of the keys to controlling bird populations is to start preventing birds before they become a problem. This can be achieved by being persistent and using a variety of techniques such as lethal control, exclusionary devices, habitat modification, live trapping and chemical repellants. Limiting access to feed and water is also important.

Any feed spills should be cleaned up, and water levels in waterers should be kept low enough that birds cannot perch on the edge and drink.

The USDA National Wildlife Research Center found that lethal control or exclusionary devices were the most effective in minimizing bird populations on the farm, while chemical repellants and live trapping were not as effective.

European starlings, house sparrows and pigeons are not protected by state or federal law, as they are not native species to the U.S., but check with your local wildlife agency to determine if local ordinances protect these species.

The primary method to reduce the bird population at Miner Institute is lethal control with the use of a pellet gun. Farm staff does this on a regular basis (often daily) because persistence is important to managing bird populations.

The minute bird mitigation becomes lax is the minute birds will start flocking to the farm in large numbers, causing huge economic losses.

In the future, Miner Institute plans to implement a few exclusionary devices including the use of carpet strips, typically used to hold down the edges of carpet with sharp tacks, which will be placed on top of the LED lights to deter birds.

Currently, the LED lights at Miner Institute are flat and provide a perfect spot for birds to nest and roost. Alternatively to carpet strips, bird spikes are also available to deter birds from roosting. These can be placed anywhere birds are typically seen roosting, as the sharp spikes will deter them from landing.

Another exclusionary technique Miner Institute hopes to implement is the use of netting, which will be placed over openings birds are typically seen flying into. Netting can be used to cover openings greater than 1 inch to prevent birds from getting in as well as to limit access to areas used for roosting, such as rafters and open ridge vents.

Plastic strips can also be hung in doorways to allow access for people and equipment, but birds will see it as a solid wall and be deterred from entering.

Other potential roost sites not able to be covered with netting should be modified or angled to prevent roosting. For instance, the lactating barn at Miner Institute was built so rafters are covered with tin, and fans are placed at a 45-degree angle causing birds to slide off when they land, which helps reduce the amount of roosting sites available to birds.

It is a continual battle at Miner Institute, as with most farms, to keep the number of birds on the farm in check. Persistence and the use of a variety of techniques are keys to controlling bird populations on a dairy farm. While all techniques are not appropriate for every farm, implementing a few of them can dramatically reduce economic losses associated with birds.  

PHOTO: Pigeons, shown here, along with European starlings and house sparrows are commonly found on dairy farms. These birds can cause thousands of dollars worth of damage by consuming and contaminating feed and damaging facilities. Photo by Peggy Coffeen.