The Rose Kennedy Greenway Conservancy posts a photo of a mantis sitting in wait on a Greenway bush last week:

Having these is a sign of a healthy ecosystem, one of our main goals in maintaining the Parks organically. We hope this is a sign of a robust and growing population of these helpful, and really-cool-to-look-at! insects.

Jennifer Forman Orth, our go-to expert for invasive species, reports that with falling temperatures, more residents can expect their homes to be invaded by these brown bugs that, when startled, smell up the joint.

In most cases, she writes, they're actually western conifer seed bugs, which showed up here in the 1990s and which, fortunately, are not messing with local ecosystems:

You can often find them resting on the sides of houses, on doors and on window screens, where they are hoping to find a way to sneak in.

Paul Holleran asks:

Anyone know what the medium sized yellow flying bugs that has infested Longwood and Brookline? It's like they are attacking.

Stephanie E adds:

They're everywhere! One of them tried flying up my nose today (in Cambridge).

Mike the Mad Biologist spies a praying mantis on Exeter Street.

I don't know, but it's climbing up your ceiling!

Fortunately, there was a pane of glass between Bob Brown and the preying mantis waiting for lunch on the side of the Wellesley library the other day.