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Matriarchal Bat Colony

Brown bat colony in attic.
Brown bat colony in attic.

Bats in attics are most common in the summertime, starting in April. These are most often matriarchal colonies often an extended bat family of sisters, aunts, grandmothers, daughters, and nieces.

One thing about bats, as far as they’re concerned: The more, the merrier!

A common scenario goes like this, It’s a lovely summer evening, the sun is beginning to set, the mosquitoes are coming out, the homeowners are relaxing in the back yard, and suddenly, they spot black figures or shadows like small, quick skydivers leaving their house and then returning to it.

These are no ordinary skydivers, though. These are matriarchal bats coming out of their happy attic roost to do their part in controlling the mosquito population of New Jersey.

Mommas will use an attic as a nursery because when pups are born their hair is very thin. A warm attic will act as an incubator. When mom goes out to get food in the evening and has to leave her babies, the pups (as bat babies are called) are kept warm by the heat in the attic. If you have found a bat in the living quarters, separated from the attic or basement of your home, you most likely have a bachelor bat.

There are some positives associated with a matriarchal colony.

For one thing, they tend to be very punctual in regards to when they come in or go out because their bodies are getting ready to take care of pups and instinct takes over. This is a pro because it makes it much easier to plan your home’s bat abatement job.

But there are also some negatives associated with the matriarchal colony.

There is a period every summer when you can’t do any kind of bat abatement on a house due to the new pups, who cannot yet fly.

If you have flightless bats in the house and then separate their mothers from them with a bat exclusion, there are several possible scenarios and none of them are pleasant.

  • The babies will die and if there are enough of them you will have a strong odor. Since bats tend to congregate in tight spots, you could spend just as much money cutting open your walls to remove the babies as you have paid for the bat abatement;
  • Some momma bats don’t take this separation lying down and will go to great extremes to get back in the house for example your front door.
  • You could wake up in the middle of the night to see a couple of baby bats crawling across your floor looking for momma or even worse, step on them in the dark!

During this nursing time, all bat abatement programs have to be put on hold. But that doesn’t mean there isn’t prep work to be done on your house so that when the babies take flight, the abatement can be completed in a timely fashion.

Abatements are safe in New Jersey up until the first week of June and then again after August 1st once the babies are flying.

In general, Fischer Wildlife Control & Repairs has a policy of performing no bat valve jobs during the last two weeks of June and throughout all of July.


To learn how we get the bats out of your house for good click here.

If you have questions regarding Rabies and Rabies Testing, click here.

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