On a rocky patch of ground, ever at the mercy of the
elements, a Killdeer sits silently waiting. Every so often it rises, exposing a
divot barely discernible and four tapered eggs that are similar in volume to a medium-sized
hickory nut. The bird carefully examines them, rearranging if needed, leaving
the tapered end always towards the center in meticulous symmetry. If the day is
cool or wet, it returns to its seated position. If it is hot, the Killdeer lets
the sun’s rays do the incubating while standing nearby. Overall, the eggs are a
creamy tan with chocolate splashes and speckles. The colors are specially
designed to work in unison, camouflaging the precious packages against the
rocks. They are all but invisible to those who are unknowing of this particular game, played yearly by
nature. The only tip to the nest’s whereabouts comes from the adults’
behavior when approached. Both parents look after the nest, usually one at a
time, and attempt to lead away intruders with a feigning technique. Pretending
to be injured, the bird flops away, tail fanned to expose rust-colored feathers
and rump that vary abruptly from the other browns found on its plumage. The
Killdeer also spreads a wing during the display, baring black-and-white flight
feathers. This is a sure sign of a nest nearby.
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| Adult on nest. |
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| The Eggs. |
After almost exactly two weeks of this, sometime during the
night of July 4th, the eggs hatched beneath the booming of Independence Day fireworks. The newly hatched young, all
four successful, can walk as soon as their down dries, but never stray more
than a few feet from their parent and are usually out of sight. With young nestled
underwing and among soft breast feathers, the adult looks like it has extra legs.
As typical of shorebird babies, the young Killdeer are
lanky. No taller than their parent’s belly, they are little more than balls of
down on stilts. The young are subtly beautiful; their plumage utilitarian to
keep them safe from predators. Their brown is darker and more mottled than the
adults, who are more ruddy. Black outlining marks the boundary between browns
above and white below; a black collar encircles their tiny throats. The young
roam, run, and pause to flick their bodies up and down, a typical Killdeer
behavior. A helpless hors d’oeuvre for many predators, there will be no time in
their life more vulnerable than this.
After a few days, the young begin a strict
routine as they can stand to spend little time away from the warmth of a parent.
By July 6th, they still never stray far from home, staying in the
small rocky patch, but are getting braver with each passing day. By 6:00am, the
family is already on the move with the adult-on-duty calling constantly. Over
the last few days, they have become accustomed to my morning presence and allow
me to get close, but not too close. I sit in the gravel patch and observe,
silently taking photos. When the chicks leave their parent’s side, it
periodically gives a single-note dee
to keep in contact. The young explore the gravel and nearby short grass for
about eight minutes, looking for food. Shorebird chicks are precocial, meaning
they are not fed by a parent in the manner typical of many birds. Once
standing, they can mostly care for themselves. After the few minutes of
adventure, the adult emits a quick dee-dee.
Sometimes all at once, sometimes one-by-one, the chicks come running, gliding
across the rocks on long legs. Occasionally, a defiant individual doesn’t
listen, much like humans and much to the chagrin of their parent. The adult is
only ever harsh when a chick ventures too far or doesn’t listen to the round-up
call. This prompts a more assertive version of the routinely patient “dee”. One at a time, the young
disappear into the adult’s downy breast feathers. It adjusts itself until all
are invisible, save for long legs. The chicks could be getting a few moments of
shut-eye, but this is mostly to keep them warm. At less than a third of their
adult size, they cannot properly thermoregulate with only a sparse layer of
down feathers. Five minutes later, the adult gives the same two-note call it
used to round the chicks up and, one-by-one, the warmed killdeerlets disperse.
The routine begins again.
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| One little one out, the rest are beneath the adult. |
July 9th marked the first day the
adults let their young stray further than about six meters from home. Over the
next week, they will wander around, exploring their two-times expanded world,
now spending more time in short grass than gravel. This is probably due to
increasing daytime temperature, food availability, or a combination of the two.
The chicks love their freedom and are innately curious. They pick at everything
in sight, pulling at weeds, lifting chips of wood, and flipping pebbles.
But life isn’t always blue skies and wildflowers when you’re
a bite-sized morsel. Approaching danger causes a quick, loud volley of dees from the adult. At this, the chicks
hunker down into the rocks or grass, disappearing from sight. This has been caused
most often by a pair of American Kestrels nesting nearby, whose young, I’m
sure, would love a tasty killdeerlet. Life continues to be very dangerous, as the
parents have loosened their reins. Sometimes during one of these scares, the
adult disappears. I suspect this is not only to lead a would-be predator away
from the young, but also because the tending adult is a danger to its young by
being near them and more visible.
Sometime around July 11th, the daytime incubation
stopped, so there was no need for them to stay as close to an adult. Though an
adult still accompanies the chicks in their wanderings, their range is now very
large. Occasionally, the adult killdeer jumps into flight and circles over the
young, calling, before landing at another location up to 20 meters away. Could
the circling behavior also be a flight demonstration? Sometimes, this is when
the adults switch shifts, other times, the same adult remains with the young. The
parent gives a normal series of dees
from the new location, slowly calling the young towards it. Close observation
on the same day shows the chicks are quickly growing wing coverts and a few
days later, they are completely formed. Despite the lack of most adult
feathers, the young killdeer are beginning to look less like bolls of cotton on
stilts and more like the finished product.
By July 17th, the killdeerlets measure up to
nearly ¾ the size of their parent. They are never stationary, ever on the move,
and run circles around the adult; often wandering far. Around the same time
incubation stopped, the young found their voices. At first their noises were
soft, but still vaguely killdeer. By July 20th, the four young had
found their voices at nearly full volume. They give a calm dee, like the adults. Usually this seems to be random baby talk,
but occasionally, the tending adult gives the “predator!” dees, to which the young respond once danger has passed.
As the birds grow, life becomes less dangerous. Nearly full
grown, but not fully feathered, the young are able to escape danger via their
own close observation and that of their tending adult. They are also becoming
too large and fast for local, open-country predators. The birds have grown very
quickly and flight feathers are beginning to peek out of protective shafts. The
four killdeerlets are also showing the tell-tale reddish eye rings and the second
of two black collars, distinct in their species. One individual is slightly
smaller than its siblings, but it keeps up well and seems not to have been too
slow in catching on at the game life.
The morning of July 21st was uncharacteristically
cold for summer, even for Pennsylvania. The thermometer read 58°F, forming fog,
and leaving a chill in the air all morning. A cold dew lay upon earth causing
purple coneflowers and yellow sunflowers to appear richly bejeweled. Though the
sun should have been up an hour earlier, fog continued to block its warm rays.
Wondering how such a morning would effect my new friends, I decided to search
for them. They had already been found by another biologist, who relayed the story I was
looking for. The adult was seen lying down with wings spread over the grass.
Beneath its warm embrace were the four young, two under each wing, too large
for brooding among the feathers of the adult’s breast. Though the killdeerlets
had not needed brooding for ten days, the temperature made today an exception.
I am constantly amazed at how the creatures of nature can quickly adapt to
temporary extremes in their respective environments.
An update on July 27th provided information that
all four young still survive. This is an amazing feat when you consider their
several weeks living as the perfect size for a predator; not to mention this
family lived in close proximity to a busy highway, constantly close to
dangerous vehicles. Though they have passed through the most hazardous part of
growing up, the four siblings will probably not all survive their first year.
Whether they will die at the hands of disease, humans, or a lucky predator,
remains to be seen. This is the brutal truth of the natural world and why small
to medium-sized birds (and other animals) have multiple young. It is now
hard-wired into the DNA of Killdeer that an average of four is the perfect
number of eggs to ensure at least one survives to carry on the species. On a
lighter note, on July 27th the killdeerlets continue to grow and now
have flight feathers that are almost completely formed. With a little
muscle-strengthening as they try out their new tools, they will be airborne in
no time at all. By July 29th, they had all “flown the coop”, to be
cliché; or at least dispersed from the immediate area.
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| One of the nest's adults and what the surviving young will grow up to look like. |
Killdeer are widespread throughout both urban and rural
North America and have adapted well to living in human-altered environments. Observing
the nesting of a bird and the raising of its young is a great way to immerse
yourself in nature. It’s so easy to get distracted in this world, but there is
something about watching an ancient process that helps draw us back to reality.
Birds are all around us all the time. They will always remain a way to stay
connected to what really matters.
For more photos in this sequence, visit: http://www.pbase.com/mpruitt/killdeer_family
All Galleries: www.pbase.com/mpruitt
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