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01/25/2013

Pest Control for Birds and Rodents

How to prevent and address these unwanted guests

By Jennie Morton
 

Prevent birds, rodents, and bats from laying siege to your facility or building.

Are birds leaving unsightly droppings on your facade? Are mice and rats threatening the safety of your kitchens? Are bats circling your building at night?

While bug infestations are common, furry and feathered critters can also create lingering pest problems. Like any other animal, birds and rodents carry diseases and parasites that can be harmful to humans and their feces produce unsightly conditions.

“Aside from the health risks, their presence creates an unacceptable work environment. These creatures are a nuisance to employees and can present a negative first impression to clients and visitors,” notes Chrissy Hansen, creative content manager at Bird-X, a provider of pest solutions. “They are also known to cause damage that compromises safety and production quality – chewing through wires and cables, building nests that create fire hazards, and contaminating products stored on the premises.”

Bird and rodent infestations are best treated with integrated pest management, which emphasizes prevention and environmentally sensitive approaches for removal.

“We need to move away from conventional treatments,” says Ron Harrison, director of technical services with Orkin. “Pulling up to a complex and dousing a facility with chemicals is old-fashioned. You need to assess and create a plan that uses the least toxic, most environmentally friendly options first.”

Unlike insect infestations, it’s rare for these pests to be carried into a facility by humans. Pest proofing, exclusion devices, and humane traps will be your weapons of choice.

A Fowl Problem
A single bird can be a welcome sight in urban areas, but a flock of pigeons won’t do your maintenance team any favors.

“Birds can cause property damage, health risks, and slip and fall liabilities to property owners,” says Shaun Johnson, a sales spokesperson for Bird-B-Gone, a manufacturer of pest control products. “Their droppings are acidic, can permanently stain buildings, carry over 60 diseases, and can become extremely slippery when wet.”

Pest Profiles: Do's and Don'ts

THE TARGET APPROVED METHODS PROCEED WITH CAUTION
RODENTS
  • Deploy mechanical kill traps, which are humane and provide a body count.

  • Seal any gaps or cracks and scale back landscaping.
  • Avoid bait traps with poison – you can’t control where the rodents will die.

  • Glue boards, while cheap and effective, cause death by starvation.
BATS
  • Use small netting (1/4-1/6 inch) around exclusion points so bats can escape but not return.

  • Seal entry points with caulk, mesh, or cloth after the bats are gone.
  • Delay any exclusion methods during the breeding season so the young are not harmed or left for dead.

  • Avoid extermination practices unless handled by a trained professional – some species are protected under federal law.
BIRDS
  • Install anti-roosting devices, such as spikes or electric strips.

  • Design out ledges and perching spots.

  • Place netting over openings and skylights.
  • Pigeons, sparrows, and starlings are considered invasive species and can be exterminated, though you may garner unwanted attention.

  • Neurotoxins in bird feed are a temporary solution that may result in bird deaths from erratic flying and overdose.
Even after you free your building from birds, you can remain at risk for ectoparasites such as bat bugs and bird lice, cautions Stoy Hedges, senior technical professional and entomologist with Terminix. Bat bugs are in the same family as bedbugs, and while they can’t survive without their animal host, they can still cause alarm among tenants.

The rise of glass facades has also seen an accompanying spike in bird deaths as they have difficulty distinguishing structures from the sky, Johnson says. A pile of dead birds won’t go unnoticed, creating unwanted media and tenant attention that makes the presence of birds a negative one.

It’s easy to visually confirm if you have a bird problem, but also look for specific areas of your building that encourage birds to linger.

“Birds are attracted to convenient rooftop perches, ledges, window sills, or any space that offers sheltered nesting areas,” Hansen explains. “They are also likely to get inside of a facility via large openings such as loading docks, garage doors, and semi-enclosed warehouse spaces.”

For new construction, you can head off bird problems with a few tricks. One of the latest approaches for glass facades is to use a reflective solar coating or a screen pattern to help birds see the walls as solid.

“You can also angle all ledges at 45 degrees, which makes them inhospitable for birds to land on,” advises Douglas Stern, managing partner for Stern Environmental Group, a pest management firm. “Use smooth metal, glass, and plastic building components, which discourage roosting. Avoid porous materials like concrete and masonry, which are inviting to birds.”

For existing flocks, several retrofit options are available. All are designed to keep birds alive but make your building an unsuitable breeding ground. For example, some devices use a mild electronic shock that gives birds a harmless yet annoying jolt whenever they land on it.

“You can also use sonic bird repellers that emit warning sounds to condition pest birds to stay away,” recommends Hansen. “Bird spikes can be applied to ledges and sills to prevent perching. Other humane tactics include bird netting, predator decoys, and taste aversions.”

Stern cautions that spikes should only be used on flat surfaces, otherwise birds are at risk of being impaled. This can be a problem if spikes are used on signs or curved areas where the angle becomes a threat if birds build nests on the spikes.

Another approach that should be used with caution is Avitrol, a chemical used in bird feed to disorient birds by causing a minor seizure. The affected bird scares off the rest of the flock by emitting distress calls. According to the manufacturer, proper administration causes no lasting side effects to birds.

Because Avitrol affects the nervous system, however, it can cause birds to fly erratically into structures and an overdose may result in death, cautions Stern. In most cases, the chemical offers a temporary solution at best as birds will eventually flock back to your site. It’s up to you to evaluate whether this product is in line with your pest control approach. PageBreak

The Cheese Stands Alone
If feathered friends from above aren’t a problem, look underfoot for uninvited guests.

“Rodents are adept at finding and pillaging anything edible and contaminating food sources with their droppings and urine. According to the CDC, rats and mice spread over 35 diseases to humans, both directly and indirectly,” says Hansen.

One reason rodents are difficult to address is because you may not have full access to your building, says Stern. You may be one of many tenants or have structures below your building that aren’t within your purview, sanitation that’s outside of your jurisdiction, or another property attached to your space.

Bats in the Bell Tower

No longer feared as vampires incarnate, bats are nonetheless a nuisance if they choose your building for roosting grounds.

“Bats are a problem in facilities where they can go undetected in high rafter areas, attics, and other undisturbed dimly lit areas,” notes Chrissy Hansen, a manager with Bird-X. “They are often found in older buildings, especially historic structures. Be aware that their droppings often contain fungal spores that can cause a potentially fatal respiratory infection.” 

Unlike other pests, bats can create a delicate legal situation. According to the U.S. Fish and Wildlife Service, there are approximately a dozen bat species that are endangered or threatened. Under this designation, these varieties are protected under federal law and cannot be killed under any circumstances.

States have the option to expand this protection to additional bats native to their region, so it’s best to be aware of existing laws. For example, some states protect non-endangered bats in the wild but permit extermination if one is caught roosting in a building. Because you may not know whether the bats on your property are federally protected or not, it’s best to let a pest professional handle the situation.

Any exclusion methods should be handled during the winter or early spring when bats are typically hibernating. “You need to avoid excluding bats from May to September because they will have their young with them,” cautions Stoy Hedges, an entomologist with Terminix. “If the adult bats can’t return to the building, then the babies will die and their remains will create odor and fly issues.”

Gaps in flashing and signage are easy for bats to squeeze through, says Hedges, so use netting or other exclusion devices in these areas as a preventive measure.

According to Bat Conservation International (BCI), “one-way devices made from lightweight polypropylene netting (less than 1/6-inch mesh), plastic sheeting, or tube-type excluders are the preferred methods for evicting bats from buildings. Exclusion devices should be placed at all active entry points and should remain in place for at least five to seven days.”

Once you are confident the bats have moved elsewhere, begin bat proofing all exclusion points. BCI recommends using silicone caulking, caulk backing rod, hardware cloth, or heavy-duty polypropylene mesh as sealants, as well as keeping an eye out for any wood or structural components that may need repair.

Mice and rodents are also quite comfortable in places that humans tend to avoid – in and around sewer drains, dumpsters, dark underground tunnels, basements, dock areas, and roofs – making their removal a potentially dirty task.

Rodents don’t need a large opening to sneak into your building. If you can fit a pencil under a door or in a crack, a mouse can fit through, Hedges explains. A small rat can use an opening the size of a dime, while a large one can use a hole the width of a quarter. Any area that emits light, like under a door, can also be used as an entrance.

Your landscaping could be a culprit as well. Rodents like to burrow in mulch and soil. You can bury wire under the dirt that will act as a barrier to rodents without harm to your plants, says Stern.

“If you have large trees with branches touching the facade or roof, you’re giving rodents a natural pathway onto your building. Cut branches a minimum of 6 feet back from the wall,” Hedges recommends. “Make sure shrubs grow upward and don’t have ground-hugging coverage to eliminate another potential hiding spot.”

If rodents become a problem despite your best effects, traps are your next line of defense. Snap traps are chemical-free and there are many humane models that kill the mouse or rat instantly, as opposed to a glue board that allows the rodent to die of starvation.

“Mechanical traps also provide a body count so you can see the results of your efforts,” Stern says. “If you use poisons, you may not know how effective the trap is. Rodents will leave the bait site and die elsewhere, creating disposal and sanitary issues.”

“As a preventive measure, however, try using tamper-resistant bait stations on the exteriors to discourage rodents from entering the facility in the first place,” adds Hedges.

Natural repellants such as cayenne pepper gels can also be used to move rodents from critical areas to another that’s more suitable for traps. This approach is particularly ideal for kitchens, food storage, or healthcare settings.

Sound waves are another humane method and use sonic or ultrasonic frequencies to drive mice away from a space. These work well as a temporary approach, but should be complemented by additional strategies.

“Sound devices do repel rodents, but pests can also adjust to noise levels because the urge for food and habitat can be stronger than the annoyance,” Stern observes. “Sonic units are certainly one of many tools you can use, but they’re not going to resolve the issue completely.”

No matter which devices you use, it’s imperative to have a year-round rodent program, emphasizes Harrison. “You will always face rodent pressure. Are you or your pest control provider routinely filling in gaps, baiting around dumpster areas, and performing inspections to look for burrowing?”

An Ounce of Prevention
How much do you have set aside in your annual budget for preventive pest control?

Facility managers can make pest prevention a priority with many low-cost strategies. Make visual inspections a routine part of your maintenance program and implement simple fixes like door sweeps, good cleaning habits, and proper food storage.

For existing pests, costs are difficult to calculate because each building is unique. Factors that affect pricing are the type of pest being addressed, square footage of your building, extent of the infestation, equipment rental (such as scaffolding or lifts), materials, and labor. Some properties may be able to resolve their infestation with an inexpensive solution such as bird spikes or rodent traps, but other tactics may be required if the problem persists.

The most cost-effective strategies are always the ones that prevent unwanted guests from making your building their home in the first place.

 

Jennie Morton jennie.morton@buildings.com is associate editor of BUILDINGS.