A pair of sandhill cranes has returned to our lake. The
tall, redheaded birds arrive at dusk to spend the night on a tiny wisp of weedy
land surrounded by water.
Flying in to spend the night on an isle in our lake |
Shortly after daybreak, they busy themselves with a bit of preening and stretching before flying off to destinations unknown. Although the birds never stay all day on our property, they stop by occasionally to probe the soil with their sharp beaks in search of seeds, bugs, berries or lizards. Inevitably, they leave, returning to the tiny island only when some inner clock tells them it's time to roost.
Sandhill crane morning rituals include extensive preening and stretches |
Our lake has been a way station for sandhill cranes ever
since a mated pair built a nest on a small island that appeared in the middle
of the lake in 2001. Sandhill cranes like to raise their young on protected
places such as small land masses surrounded by water or wetlands. We had a
period of extreme drought 13 years ago and although lake levels have fluctuated
widely since then, the cranes' commitment to our property hasn't wavered.
Unusually low water levels in 2001 exposed a long island of peat in the middle of our lake. That year a sandhill crane couple nested on the island and hatched out two babies. |
Most years, a pair nests on one of the tiny isles in the
north end of the lake and succeeds at raising one or two babies. There have
been seasons, however, when the birds didn't reproduce at all or their young
failed to survive.
During the especially wet spring of April 2011, the sandhill cranes abandoned a nest with 2 eggs in it when water levels rose and flooded them |
As a group, sandhill cranes are doing well with about
500,000 birds worldwide divided into six subspecies. Three of those subspecies,
the Greater, Lesser and Canadian sandhill crane, are migratory birds while the
other three, the Mississippi, Cuban and Florida sandhill cranes, live their
entire lives in limited regions. The migratory populations — cranes that nest
in the northern climates and fly south for winter — are either stable or
increasing, but the outlook isn't as bright for the non-migratory birds.
Mississippi and Cuban sandhill crane populations are dwindling with both
subspecies listed as endangered. The Florida sandhill crane population is doing
a bit better even though it consists of only about 5,000 birds. The Florida
Game and Freshwater Fish Commission lists the Florida sandhill crane (Grus
canadensis pratensis) as threatened.
Large flocks of migratory sandhill cranes come to Florida in the winter |
Because I see them in summer when migratory cranes have returned to their northern homes, the pair that spends the night on our lake is among that small group of year-round residents. I suspect they are the same pair that we've been seeing for years.
Our resident crane couple with their most recent offspring |
One of many interesting behaviors is their tendency to
return year after year to the same nesting place. The cranes, which can live up
to 20 years in the wild, are monogamous birds with both parents participating
in the care of their offspring. Young cranes are called colts. A sandhill crane
nest usually includes one or two eggs that hatch after about a month.
Occasionally, both baby birds will grow to maturity but often only one bird
survives.
Baby cranes that do live stay with their parents for about
nine months before leaving to join a flock of other juvenile birds. These
gatherings of immature, non-breeding cranes provide the young birds with
opportunity to find mates and engage in courting rituals that include
extravagant dancing behaviors. (Click below to see movie of mating dance.) Once mates have been selected, partners often
stay together for several years before the successfully raising babies.
Like many Floridians, I find our resident sandhill cranes
fascinating. These large birds are not only beautiful, but also surprisingly
tolerant of humans. They often forage for food in our lawns and rest in the
shade of our trees. Yet, because we see them so frequently, it's easy to take
our resident sandhill cranes for granted.
The sandhill cranes foraging through our front yard in 2012 |
Although I often wish the sandhill cranes that spend the
night on our lake would spend the day on our property, too, with a population
of less than 5,000 birds, I try to be grateful that they come at all.
Please visit my YouTube channel to see several more videos of our resident sandhill cranes and their babies.
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