Page 14 - Discover SPRING 2022

Humming Along CONTINUED

hummingbirds in eastern North America and is actually an elastic micro-pump. (If understood
they are what you will see coming to your feeder. correctly, this is what happens): By collapsing and
While there have been sightings of several other expanding the tongue, fluid at the tip is forced into
hummingbirds in Virginia their visits here are rare the groves along the the tongue. Then, the top of
to “extremely rare” and they are just passing through, the tongue (closest to the mouth) bends causing
probably on a migratory path. “elastic energy”which creates a pump. An example
of “potential” elastic energy is a trampoline or a sling
Keep your feeder up through September or
shot or a rubber band. This pump allows the bird to
until all activity stops, this might even be as late as
gather nectar much faster than capillary action would.
early November. It seems there are always one or
They are able, scientists have learned, to drain 5 to 10
two stragglers who for one reason or another didn't
drops of nectar from a flower within 15 milliseconds
leave with the majority of their fellow hummers.
(about 100th of a second). We humans create a
Don't worry about throwing them off their migration
simple pump with our mouths when we draw liquid
schedule. They follow flowers and migrate in response
through a straw by sucking the air out of the straw
to hormonal changes triggered by the decreasing
and creating a vacuum.
length of daylight. Nothing you can do will make
them stay beyond a safe departure date. They need to You will often hear a hummingbird before you see
bulk-up to survive their journey back across the Gulf one. They fly more like an insect than a bird and they
of Mexico so they will appreciate your feeder right up were no doubt the inspiration for the engineering
until their Virginia visit ends. that went in to producing helicopters. Researchers
from Stanford University and Wageningen University
The average wing movement of a hummingbird
tested the hover performance of 26 hummingbird
is 53 beats a second. The fastest recorded rate is 80
wings from 12 different species. These wings were
beats a second. They fly at speeds of 34 miles per
reportedly some they had laying around in a museum.
hour and they have the highest metabolism of any
They tested the wings in a machine that measured the
warm-blooded creature on our planet. Due to their
torque and lift they would produced at various angles.
very high metabolism, when food is scarce or at night
Their study found the aerodynamic performance of
when they are not foraging, hummingbirds conserve
the wings “remarkably similar” to that of the rotor on
energy by going into “torpor”, a state similar to
a drone but the wings were 27 percent more efficient,
hibernation. This slows their metabolism to 1/15 of
which lead engineers to make adjustments to the
its normal rate. Besides nectar, which makes up most
drones.
of their diet, hummingbirds also eat insects and small
spiders. Don't confuse the hummingbird with an
insect called a Hummingbird Moth. These moths
If you have the opportunity to closely observe
have feeding and flight patterns very similar to
hummingbirds, you'll discover that it is not their beak
hummingbirds and are easily mistaken as “baby”
that goes into the nectar in your feeder but rather
hummingbirds. They hover in mid-air while
their tongue which protrudes well beyond their long
gathering nectar and make the same flight noise.
beaks. In fact, they can extend their tongues twice
They are considerably smaller than a hummingbird
the length of their beaks. With the naked eye, their
and they have antennas on the top of their heads and
tongue looks like a human hair or a very thin wire
the legs of a moth rather than those of a bird. These
flashing in and out of their beaks. Researchers have
moths live only 3 to 4 weeks while hummingbirds
learn, that these tongues have long groves on them
have an average life span of 5 years. The oldest known
that look like open cylinders. Nectar flows through
ruby-throated hummingbird lived for 9 years. That's
these grooves into their mouths. For 180 years it was
18 lifetime flights across the Gulf of Mexico. Pretty
believed that the nectar entered their mouths through
impressive.
capillary action. In simple terms, a paper towel
absorbing water is an example of capillary action. The Information for this article was found at various
water is able to defy gravity and “climb” quite high Online websites featuring news reports and research
depending on the absorbency of the paper towel. results regarding hummingbirds. Some information
was also from personal experience with feeding
Recently, however, an experiment that was 5 years
hummingbirds and visually observing their behavior.
in the making, proved that the hummingbird's tongue
12 Discover Smith Mountain Lake SPRING 2022