Bats roosting in or on home can become a health and safety issue
DEAR JOAN >> We have bats in the roof apex. They are no bother, and we rarely see them. Sometimes the bats crawl into the house. So we leave the doors open and they fly out!
Are they damaging the house? They are so delicate, we don't want to hurt them.
— Patty, Ben Lomond
DEAR PATTY >> While it's good to have bats in the neighborhood, it's not a good idea to have them living in or on your home.
The biggest risk is rabies. It's unlikely you'll be bitten by a rabid bat, but you could expose yourself to rabies, if you handle it with bare hands.
The other, more common risk is histoplasmosis, a lung infection caused by breathing in a fungus that grows on bat guano and bird droppings. Symptoms include fever and cough, and it can last for months.
Guano can also cause structural damage to wood and other building materials, which can lead to roof leaks and weaknesses that can may become an issue.
Guano can accumulate anywhere the bats roost, so you might want to hire an expert — this is no DIY project — to remove it and block off the roosting places. An expert can deal with the bats without harming them and install exclusionary devices. We're coming to the end of the pupping season, but you'll need to wait until early autumn to take action.
If you want to try doing it yourself, it's not recommended you try to physically remove them. Your only real option is exclusion. You'll need to find out where they are getting into the house and seal off the entry point.
To discourage roosting, hang shiny objects, such as old CDs, and install lights in those areas. Bats also don't like the smell of cinnamon, eucalyptus and peppermint.
Because we like bats in general, look into installing a bat house on your property, but not on your home.
DEAR JOAN >> I've lived in the East Bay for over 50 years and had never heard of or seen a tarantula hawk wasp. Now for the last three years, we have them on our property, and I see them when riding my horse on Mount Diablo. I've seen them in Tilden.
Knowing how painful their sting is, I'm naturally scared to death of them, and they're creepy looking, too. How come they're so prevalent all of a sudden?
DEAR LINDA >> You know how when you buy a new car, you suddenly start seeing other cars of the same make and model or the same color? I think it might be the same with tarantula hawks — you know what they look like, and so you notice them when others might not.
Although the wasps are associated with desert regions, they're common in the Bay Area, perhaps drawn by the presence of tarantulas, which they use to incubate their young, and an abundant supply of food, which includes nectar, pollen and the juice from fruits and berries.
They will sting if provoked, but basically they are not aggressive. Their sting is considered one of the most painful in the insect world, but while the pain is incredibly intense, it fades after about five minutes and is not fatal. Still, you're wise to give them a wide berth.