NORTHERN VIOLET-GREEN SWALLOWS
by Ranger Naturalist Jennings King
At 11:30 a.m. on July 17 last summer a nest of five Northern
Violet-Green Swallows (Tschycineta thalassina lepida) was found in an
abandoned woodpecker hole in a small clump of lodgepole pine trees
(Firms contorta) in the meadows adjoining the southeast portion of
Madison Junction campgrounds. The little ones were being fed at quite
regular intervals by their parents. After coming within fifteen or
twenty feet of the nest, the adults did not attempt to bring in more
food but kept making their flight in large circles around the tree.
The little ones dropped out of sight as I came within five feet of
the nest. While I quietly stood there the little heads popped up until
at one time four heads protruded from the opening. The parents would not
venture close.
After twenty minutes of observation and picture taking, one brave
baby took flight. One of the parents immediately came to the rescue and
as the young one weakened he was given several "boosts" from behind,
resulting in a strengthened and higher flight. After circling two or
three times the bird made a perfect landing near the top of a
neighboring tree.
A second young one took flight in about five minutes but he did not
have any encouragement from the parents so flew directly to a tree about
thirty feet away. His landing showed lack of practice but he did not
fall.
In the following ten minute interval no other birds indicated their
intentions to fly so I departed. Two hours later I returned to the nest
and found that all the birds had flown away, leaving the site for other
feathered friends.
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YELLOWSTONE'S MYSTERY SOUNDS
by Ranger Naturalist Neil Miner
The music of Yellowstone Lake has been a subject of discussion since
the days of the early explorers. The sounds have been heard by hundreds
of individuals and an equal number of theories have been advanced for
the cause.
Early one morning last September, the late Assistant Naturalist Crowe
and the writer were privileged to have a splendid audition of this
phenomenon. The sound seemed to arrive unannounced from some point at no
great height above the north end of the lake. It traveled rapidly in a
horizontal plane out over the lake toward the south. The sound was
audible for about ten seconds.
To the writer it sounded like a rapidly whirling current of air
moving at great speed horizontally above the lake. It had no apparent
lateral range but gave the impression of being merely a local
disturbance, producing a swishing sound of varying volume with a faint
trace of a whistle; somewhat akin to the sound of ducks in flight.
The morning was perfectly clear and calm and not a bird was in sight
in the air, so it could not have arisen from that source.
It is the opinion of the writer that a possible explanation may lie
in the fact that currents are set up in the lower atmosphere due to
diurnal changes in temperature. This fact, accompanied with air
movements down from the high peaks surrounding the lake, under certain
conditions, causes horizontally moving whirlpools of air, similar to
those one often sees across the calm surface of the lake. The whirling
air pocket traveling at terrific speed in a horizontal manner across the
lake until dissipated at some point remote from the observer, might well
produce the sound that has been so often heard.
