The Male Scarlet Tanager |
It’s likely that one if not both of these males
is already breeding. Back in mid-May, in this same section of the woods, I
watched a courtship ritual taking place between a male and female tanager.
This consisted of the male arching his back and drooping his wings while the
female, in a gesture that mimics a begging fledgling, bowed her head and
quivered her wings. Luckily for me, this behavior took place only about 10 feet
off the ground, so it was very visible.
Last year 2 Pairs of Scarlet Tanagers nested in approximately this same area, though I never did locate the actual nests. The species tends to place its nest fairly high in the forest canopy, where their domestic activities are well shrouded by foliage. Last year, one of the female tanagers was seen feeding a recently fledged cowbird chick. We can assume that the tanager’s own eggs or nestlings were destroyed by the female cowbird before she laid her egg(s) into the “foster” family’s nest. The tanagers, like scores of other songbirds, are very susceptible to brood parasitism as practiced by the Brown-headed Cowbird.
Some of the forest that the tanagers nest in is part of a
recent acquisition of our nature preserve. Before it was ours the property had been selectively logged
twice in the past 12 years. The forest gaps created by the loss of large trees have helped to
facilitate the cowbird’s penetration deeper into the forest; the result of this
is that fewer woodland songbirds successfully raise their own young. Now that
we control more of the forest, we can expect that over time, the forest gaps
will fill in, mature forest will recover and less brood parasitism should take
place.
No, he's not tearing out his own red feathers, that's a berry in his bill! |
Later in the summer, before the tanagers begin their journey
to Central America for the winter, the male will start to molt out of his
scarlet breeding plumage. For a while his feathers will look very blotchy, with
lingering patches of scarlet on top of irrupting yellow contour feathers.
The Questionmark Butterfly has become exceptionally common
in recent weeks. Not as ubiquitous as the Red Admiral became earlier this
spring, but still impressively common. Always one of my favorite butterflies,
these medium sized orange, black, and brown butterflies often allow a close approach, so one can really get a good look at its detail. The Questionmark is an
anglewing butterfly and a pretty decent dead leaf mimic, so when their wings
are closed, depending on the background, you might not notice one so easily. On
the underside of their wing, there is a small silvered mark in the shape of a
question mark; this is how the species earned their common name.
This time of year, I enjoy watching female butterflies lay
their eggs and I’m particularly curious about what species of plant they will
select to lay their eggs on. The other day I saw a Questionmark lay a single
egg on Narrow Vetch. Interestingly, this is not one of the acknowledged food
plants for the Questionmark’s caterpillars.
A few days later, I checked on the tiny egg and to my surprise I found that 2 more Questionmark eggs had been laid on the same vetch plant. About a foot away from the vetch is a small American Elm seedling; the elm is a known foodplant for the questionmark, so it’s possible that the elm was the targeted food all along. Hopefully, we’ll find out what happens when the butterfly’s eggs hatch.
The egg of the Questionmark Butterfly on Narrow Vetch |
A few days later, I checked on the tiny egg and to my surprise I found that 2 more Questionmark eggs had been laid on the same vetch plant. About a foot away from the vetch is a small American Elm seedling; the elm is a known foodplant for the questionmark, so it’s possible that the elm was the targeted food all along. Hopefully, we’ll find out what happens when the butterfly’s eggs hatch.
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