Small Milkweed Bugs

Small Milkweed Bug, Lygaeus kalmii

I’m still working my way through the photos I collected last week. It’s a good thing I got so many blog topics backed up, because since bringing the puppy home I’ve barely had any time to go out and take some more. These were taken Friday, just before heading out to get the pup. Friday was gorgeous. Beautiful temperatures, clear skies, and even though it was rather windy, the air was warm, not nippy. I could’ve stayed out all afternoon, if I didn’t have places to be. Since I did, I just stuck around the house, but I turned up a few things there so I was still happy.

These Small Milkweed Bugs (Lygaeus kalmii) were all over the sunny parts of the foundation. The concrete had warmed up in the sun, and they’d gathered there to soak in the heat. There were quite a few also in the dead vegetation, so I’m not sure whether the bugs had been wintering in cracks in the house, or tucked beneath all the vegetation on the ground. Given that last spring I would find them crawling around the dead grass in the meadow, however, I’m inclined to believe the latter.

Small Milkweed Bug, Lygaeus kalmii

It’s funny that, growing up, I never noticed them around, while out here they seem quite common. We had milkweed there, too, but not nearly the amount of it that we have here (in fact, I’m not sure I’ve ever seen an area with quite so much milkweed as here), so I wonder if it’s simply a function of food plant abundance. Or, perhaps, I just wasn’t that observant as a kid.

They’re easily confused with the Box Elder Bug (Boisea trivittata), which is actually what I thought they were at first (which is funny – I did the same thing last year). Box Elder Bugs will overwinter in the nooks of your house and are often encountered in large groups at the first thaws in the spring, so it would make logical sense. Small Milkweed Bugs share the black and red aposematic (warning) coloration telling predators they don’t taste good (the result of the toxins in the milkweed seeds they feed on in the fall), but they have more red than the Box Elder Bugs. The pattern of the red creates a heart shape of the black on its back.

Of course, there’re not many milkweed seeds (their dietary item for which they’re named) to eat at this time of year. During the early spring, the bugs can get by scavenging dead vegetable matter and detritus or even preying on other insects. They switch to nectar once flowers start blooming, which carries them through the summer. When you’re most likely to notice them, though (assuming they don’t start crawling over your house foundations in the spring) is during the late summer and fall, once the milkweed pods develop. Then both they and their nymphs can be quite common on the plants.

Small Milkweed Bug, Lygaeus kalmii


Author: Seabrooke

Author of Peterson Field Guide to Moths. #WriteOnCon Mastermind. Writer of action/thriller SF/F YA. Story junkie. Nature nut. Tea addict. Mother. Finding happiness in the little things. Twitter: @SeabrookeN / @SeabrookeLeckie

5 thoughts on “Small Milkweed Bugs”

    1. I think they’re full hibernators, LB, at least for the main winter period. During the late fall and early spring, though, when their hiding spot warms up enough to warm up their body, too, they’ll come out and sunbathe for a bit before hiding away again at nightfall.

  1. My family and I just bought a house and we are moving in and notice a few of them an hour in different areas of our house. Does anyone know why and what we can do to rid them of or house? I can’t live with them inside. When we moved in, there were piles of dead ones in different areas of the basement, and randomly scattered around the house, by windows…floors. Help!

    1. If they’re a real problem, Colleen, your best bet is just to scoop them up and dump them outside. If it looks like you’ve got a serious problem, then you should get your house checked for drafts/cracks, because that’s how they get in. Or just check yourself – windows and doors are often big problem areas. If you seal up your house’s cracks, then not only will it be more energy efficient when it comes time to heat it in the winter (or cool it in the summer), but you’ll also keep all the unwanted crawlies outside where they belong.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: