The History of Bat Control in Massachusetts and Rhode Island
In Massachusetts and Rhode Island it is estimated that 80% of the bat population resides in houses and other buildings. Why do bats choose to live in houses? The most likely answer is that they do not have a choice. The rapid development of open land in our area has all but wiped out all of the natural bat habitat. Bats now live in buildings because this is all that is available to them in our area.
Massachusetts and Rhode Island are home to two species of bats — small brown bats and large brown bats. Small brown bats are seasonal bats. They arrive here in large numbers every spring and will stay here for the summer months. Sometime in October they migrate to the mid-Atlantic states or to large caves in upstate New York for the winter.
Large brown bats are year-round residents. These bats hibernate in attics during the winter months, although they will occasionally awake during the winter months if we get a warm stretch of weather. It usually takes three days in the 60's in January or February to trick these bats into thinking that spring has arrived. Every year we will get a large volume of "there's a bat in my house!" calls in the middle of winter when one of these warm spells takes place.
Bats in Houses and Attics
Bats in houses, bats in attics and bat infestations are a problem for homeowners for a number of reasons. If bats are occupying an attic of a house there is always a chance that a bat or multiple bats will drop down into the house during the night. Once in the house, bats will fly throughout the house in an effort to get out. If a bat comes in contact with a person, it is advised that the bat be sent for rabies testing immediately. If the bat cannot be found the affected person must have rabies shot administered as soon as possible.
Bats living in attics will also leave behind droppings (guano) and urine deposits. Over time these deposits will build up and cause damage to insulation as well as leaving stains on ceilings and walls as the urine is absorbed by the drywall. Once it gets to this stage the deposits will also create an intense odor. Bat guano is very dangerous to humans if it is touched, ingested and especially if the dust from dried bat guano is inhaled. Inhaling dried bat guano spores can lead to a deadly disease called Histoplasmosis. This would be most likely to occur when sweeping up dried bat guano in an attic without proper safety equipment. The Centers for Disease Control have additional information on histoplasmosis.
Pest Control for Bats
By definition there is no such thing as "Pest Control for Bats" or "Bat Pest Control." Back in the 1970's and 1980's pest control companies in our area began getting calls about bats that had taken up residence in attics of residential houses. The pest control companies were stumped because they had never dealt with residential bat removal issues before. In typical "pest control fashion" these companies began to spray the visible bats with pesticides in an effort to kill as many as possible. They would return to these houses once or twice a year and simply kill as many bats as possible. This was a temporary solution and a lousy one at that. These companies were killing thousands of bats needlessly and charging the customer for a service that didn't produce a permanent solution. They would spray the visible bats (in any attic there will only be a very small percentage of bats that are visible. Most bats in attics roost in areas that are completely inaccessible to humans) and not seal any of the areas of the roof that the bats were using to gain access to the attic. The bats that did not get sprayed simply continued to inhabit the attic and nothing was solved. These bat control methods were lousy and the industry was aware of it. Slowly but surely during the 1980's a new method of bat control started to take shape. The new method of bat control came to be known as bat exclusion. The days of pest control companies using poison for bats, spraying bats with chemicals and needlessly killing thousands of bats was finally over.
The bat exclusion process is now used by all ethical bat control professionals across the country. The bat exclusion process allows the bat control technician to safely remove all bats from a house and attic without using any chemicals and without killing any bats. The bat exclusion process is an all natural method that is widely accepted as the most humane and the most effective bat removal process for dealing with both commercial and residential bat infestations.
Interestingly, I've spoken with wildlife professionals all over the country and no one that I've ever spoken with knows for sure who invented the bat exclusion process. It was more than likely a network of wildlife trappers across the country who put their heads together to come up with the process. From there it spread across the country and is now practiced in every state.
Repellants and Ultrasonic Devices
My customers are always asking me about different types of repellants and ultrasonic devices. Most concoctions that are marketed as "bat repellants" are nothing more that ground-up mothballs. Take a look at the active ingredients on the back of the container. If it says "Naphthlalene" anywhere on the label it is nothing more than good old-fashioned mothballs that have been ground into a powder. Do mothballs work to deter bats? Absolutely not. I have seen attics with thousands of mothballs covering the floor and hundreds of bats happily hanging on the rafters. Mothballs will create such an incredibly strong odor in your home. They will also create a toxic environment for the people that reside in the house. The only permanent solution to any bat infestation is mechanical techniques: all potentials entrances must be sealed.
For information on the effectiveness of "ultrasonic sound emitting devices" read the warning that was issued by the US Federal Trade Commission. It details unsubstantiated claims that are being made by the manufacturers of these devices and includes the following statement:
Prior FTC complaints alleged that any reaction by rodents to ultrasound would be temporary at best because rodents become accustomed to ultrasound and will return to their nesting or feeding areas even in the presence of an ultrasonic device. Furthermore, previous FTC complaints alleged that ultrasound devices do not control insects.