Last April, when the lone offspring of the sandhill cranes
that nested on our lake was eight days old, the entire family left to make a
new home on acreage that abutted our own.
To say I was disappointed would be an understatement.
I had become completely entranced by the baby crane's
development from egg to hatchling. Everyday I'd go out and take pictures,
watching how quickly the chick learned new skills and how involved both parents
were in their hatchling's education. When the family suddenly left, I was sad
and worried.
Nesting crane |
After realizing where they went, I'd peek through the bamboo
hedge dividing our two properties to catch a glimpse of the growing chick as it
followed its parents across my neighbor's pastureland.
Watching the baby crane from afar |
I became so attached to
the crane family that it took a while for me to adjust to their departure.
Eventually, however, I accepted the fact that they weren't coming back.
Of course, that's when they returned.
Three months ago, the entire family came back. I knew it
was the same birds because on their first return visit, they made a beeline for
the birdfeeder where in April, the female crane had stuffed herself on seeds
just before laying eggs.
The three sandhill cranes returned |
Although I had long since removed the feeder (it's unwise to feed sandhill cranes because they can get aggressive), the birds remembered where it had been and proceeded to poke the ground where birdseed used to fall.
The bird feeder was gone but a millet plant that grew from birdseed that had fallen on the ground remained. One of the birds checked it out. |
That evening and every night since, the three cranes spent
the night on the tiny island where they originally nested. Just before dark,
they fly in to settle in the shallow water on the north end of the lake where
small islands reemerged after summer rains ended. They roost on those small
spits of land — safe, secure places to rest.
I watch the cranes at dusk and again in the morning before they fly off to wherever it is they spend their days. Aside from noticing how big the baby crane has gotten (all grown up!), I've noted how territorially possessive they are. For birds that only spend part of each day in our lake, their territorial instincts are off the charts.
Just the other day, my husband Ralph and I were taking an early evening stroll. Overhead an osprey was flying while a great blue heron was searching for prey in the shallow water.
Osprey flying by |
Great blue heron minding it's own business |
The crane family had not yet arrived, although they were due any minute. Sure enough, as I watched the heron in the waning light, the crane trio swept in on silent wings.
Flying in for their evening repose |
Usually after the birds land, they engage in a routine set
of evening ablutions that include stretching, preening and poking about in the
water. This evening, however, rituals were set aside as the birds focused their
entire attention on the intruder. With a determined gait, the trio proceeded to
parade single file toward the hapless heron.
When the lead crane (I'm guessing, the male) was only a
couple feet away, it jumped up, flapped its wings and bellowed as if to say,
"What do you think you're doing wading in this end of the lake? Go find
somewhere else to fish! These are our islands!"
Marching toward the heron |
And scaring it away... |
Without hesitation, the heron flew off toward the southern
end of the lake. With the "threat" taken care of, the crane family
immediately turned around and returned to their roosting spot where they set
about the lengthy process of cleaning and preening.
With the heron scared away, the cranes are ready to begin their nightly pre-sleep stretching and preening |
Over the past few months, I've witnessed similar displays of
sandhill crane territorial behavior. In addition to great blues, I've watched
them chase away tricolor herons, great egrets and plenty of ibises.
Tricolored heron |
None of those situations involved any physical threat to the cranes, but in previous years, I've also seen protective crane parents scare off alligators and otters, threats that were indeed potentially dangerous.
An alligator could be a potential threat to sandhill cranes especially if they are raising chicks |
Lately I've been wondering why sandhill cranes bother to
frighten off non-predatory animals. Experts suggest the behavior is due to
competition for food supply. But I wondered if all their possessive posturing
is just another step — perhaps the final step — in sandhill crane parenting.
Ever since the chick hatched 10 months ago, the adult birds
have been teaching their baby how to do what sandhill cranes do — find food,
build a nest and get away from nosy photographers who drift too close in their
aluminum rowboat.
Teaching baby what to eat and how to find food |
Now that their sole offspring is ready to leave the family
unit, maybe they're doing what most parents do — trying to fit in a few last
minute lessons on how to survive in the real world. If bellowing out a warning
while jumping up and down with flapping wings scares away a harmless heron,
maybe it will work on actual threats too.
I'm not sure if that's the real purpose behind these sudden
shows of territorial displays, but if it is, I can only hope Junior got the
message. Growing up and making it on your own isn't easy for anyone — sandhill
cranes included.
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