40 Nebraskaland • August-September 2020
sticky substance you see when you break off a leaf. That
latex is toxic to most creatures, but some invertebrates have
developed techniques to deal with that toxicity and use it
to their advantage. In the case of large milkweed bugs, the
toxic chemicals (cardenolides) are stored inside specialized
compartments and can be released when the insects are
threatened.
The strong orange and black coloration of the large
milkweed bug is similar to that of other invertebrates that
feed on toxic plants and use that toxicity as a defense
mechanism. Monarch butterflies, of course, are in the same
category, along with ladybugs and the smaller milkweed
bugs mentioned above. Large milkweed bugs pass their
toxicity along to their eggs, which are also orange-colored
and, apparently, taste really bad.
Both adult and juvenile large milkweed bugs feed mainly
on the seeds of milkweed, which fuel strong growth and
reproduction. They will sometimes eat other parts of the
milkweed plant — stems, buds or flowers —
but they fare
much less well on that diet. Adult
large milkweed bugs will
branch out and feed on nectar from various kinds of flowers.
They also have been observed eating monarch eggs, aphids
and even others of their own kind, but it's not clear whether
this is out of desperation or a common occurrence.
Like other "true bugs" in the order Hemiptera, large
milkweed bugs feed through a straw-like mouthpart called
a rostrum. Milkweed bugs insert that rostrum into seeds and
inject their saliva into the seed, which basically pre-digests
it. They then suck up and consume the liquefied contents of
that pre-digested seed.
Large milkweed bugs lay eggs in or on seed pods. When
those eggs hatch, the young bugs, called nymphs, have a
