The Daily Bucket is a place where we post and exchange our observations about what is happening in the natural world in our neighborhood. Each note about the bugs, buds, and birds around us is a record that we can refer to in the future as we try to understand the patterns of nature that are quietly unwinding around us.
Gooseville, WI
This time of year swollen milkweed pods sway lightly on the breeze in bright sunshine. On my hike, I grab a closer look at some of the light green pods that are covered with a dozen or so bright orange and black bugs. These harmless milkweed bugs are 'true bugs' in the order of Hemiptera ('half-wings'). That means you can actually call them bugs without being frowned upon by eminent entomologists.
large milkweed bugs (Oncopeltus fasciatus)
True bugs don't have mouth parts for biting, chomping or chewing. Instead, they have a tubelike beak for sucking and sipping seed fluids with side-by-side mouth tubes, one to pump digestive enzymes into the tough milkweed seeds and the other to siphon up the softened plant material. I think of it as the amazing spit, sip and suck method.
They don't harm the milkweed pods and can only feed on the outside layers of seeds. That leaves plenty of seed fluff to fly away to sow the future.
These little seed eaters, better yet, seed suckers, come in two flavors, small milkweed bugs (SMBs) Lygaeus kalmii and large milkweed bugs (LMBs) Oncopeltus fasciatus. Their orange and black colors are brilliant and stunning.
LMB actual size
These guys and gals are gregarious feeders on ripening milkweed pods. Adults and nymphs of all sizes benefit from communal feeding behavior.
[More feeding tubes = more spit and saliva = more softening of the seeds = more food for everybody.]
I brushed my finger gently on the pod and they scattered in all directions. Some were alarmed and fell to the ground pretending to be lifeless and dead. Clever. Most insect predators prefer their prey alive and moving. Clever bugs.
They scattered when I brushed the pod.
boxelder bug (Boissea trivittata)
These behavioral methods are really unnecessary, because milkweed bugs, like monarch butterflies, taste nasty. They're poisonous to predators due to cardiac glycosides that they sequester in their bodies after eating milkweed.
Milkweed bugs don’t attack crops, carry disease or otherwise cross paths with humans, unless one raises milkweeds or collects seeds or is on a hike.
Orange and black color patterns are called, aposematic, meaning 'being conspicuous and serving to warn.'
There’s speculation that the nasty, non-poisonous boxelder bugs that plague us are milkweed bug mimics. What do you think?
'Orange on black. Stay back!'
small milkweed bugs
(Lygaeus kalmii)
The uniqueness of their life cycle is that SMBs overwinter here in Wisconsin and the northern latitudes, while LMBs freeze out. SMBs are permanent residents and LMBs are migratory, following the milkweed crop north in summer and retreating south in fall. The little SMBs crank out the antifreeze and survive northern winters. LMBs don't. Who knew?
What's going on in your backyard? Got cool bugs? Other critters? New blooms? Drop a note in the bucket and include your location. Everyone is welcome here.
♥