Seeing that Larry Sirvio has publicized my warbling vireo (WAVI)
nestlings photo, I think I should explain how it came about. To be
honest, if I came across such a close-up photo of nestlings, I'd
certainly have some negative thoughts about the ethics of the
photographer. For this reason, I was hesitant to post the nestling
photo; but because I thought it might be useful to some folks, I posted
it along with the nest photo.
I'm a birder, not a photographer, but I always carry my camera (just a
fancy point & shoot model) when my wife, Maureen, and I are working in
our Breeding Bird Atlas block. I have some other more distant shots of
nests and fledglings, but nothing worth posting.
Two days prior to taking the photos we were walking a trail in our BBA
block and a male WAVI landed near us with an insect in its bill. It
promptly sang (ensuring a positive ID), then flew off carrying the
insect. We followed, and within probably less than 15 minutes we
witnessed 4 food-carrying flights. By the fourth flight we were in a
position to see the food being delivered to at least 2 large nestlings.
The nest was about 7 feet off the ground at the end of a burr oak
branch. We added it to our field notes as "NY" ("nest with young seen
or heard"), and we moved on to try our luck with the yellow-throated
vireo (YTVI) that was singing a bit farther down the trail. At no time
did we get within 30 feet of the WAVI nest.
Having failed to see any food-carrying by the YTVI on our first attempt,
we returned two days later to try again, and the trail took us past the
WAVI nest. We watched it for a bit, but we saw no feeding activity and
heard no adult vocalizations. This was quite the opposite of what we
had observed on our previous visit, so we concluded the young had
fledged and the adults had moved off with them. We never had seen a
WAVI nest before, so we went over to take a close look. I took a photo
from below (also posted in the BBA gallery), and we admired the
intricate woven construction. I reached up and pulled the branch down
to our eye level to examine and photograph the nest interior. We were
shocked to find the nest was still filled with nestlings. The chicks
didn't move at all. Since the "damage" was already done I quickly
snapped two photos and gently released the branch to its normal height.
Then we continued walking past the nest in a large loop to avoid
dead-ending our path under the nest. As we left the area there still
was no sign of the parents. However, when we passed by quite a bit
later we did get a scolding from an adult.
I'm convinced that our encounter didn't lead to premature fledging, nor
make the nestlings more vulnerable to ground predators. If avian or
climbing predators happened to be watching us, they might have
investigated after we departed. But we were only at the nest for about
a minute or two at most (3 quick photos), so that isn't too likely. I
don't think our unintentional encounter with the nestlings had any
significant negative impact on their welfare.
So that's the story.
Ron Refsnider
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