Nature
Notes for May 29, 2015
The
loud chattering from the swampy area carried to us from over 2 km. distance. We
drove closer. Although the sound was very near the road, we could not see the
birds through the trees.
We
had found at least two Sandhill Cranes near the south shore of Rice Lake. For
such a large bird, they can be very difficult to see, but not to detect. Their
trumpeting call carries over quite a distance and they are very vocal when they
are setting up territory.
Sandhill
Cranes have only fairly recently moved into Northumberland County in any
numbers. In the twenty years between the two Ontario Breeding Bird atlases,
there was a very noticeable increase in their presence in southern Ontario.
Sandhill Crane family
photo © Chris Geddes
Locally,
a few Sandhill Cranes have nested on the marshes on the north side of Rice Lake
for about twenty years. This spring, there has been an increase in sightings
throughout Northumberland County. They have been found several places along the
south shore of Rice Lake. Sightings have also been reported from areas around
the Northumberland Forest, Presqu’ile Provincial Park and Murray Marsh. There has
been an increase in sightings of cranes during fall migration, too, sometimes
of flocks numbering over 30 birds.
Frequently,
Great Blue Herons are mistaken for cranes, but they are not closely related at
all. Both are gray in colour, although the cranes often have a rusty tone to
their plumage. The rusty colour is caused from the birds rubbing iron-rich soil
on their plumage.
Although
Great Blue Herons and Sandhill Cranes are about the same size, that is 5 feet
tall, cranes have a bare forehead, which is red in the adults, and a less
upright posture than the herons. The crane beak is heavier and thicker than the
heron. In flight, cranes fly with their neck stretched out, while Great Blue
Herons fly with their neck curled up.
Sandhill
Cranes prefer to nest in wet meadows and swamps, adjacent to dry upland areas.
They make their nest of dry herbaceous vegetation to which they may add some
green vegetation as the season progresses. Sometimes the nest is a large mound,
sometimes only a lined scrape.
When
they are courting, Sandhill Cranes perform an elaborate “dance” which involves
much head bobbing, bowing, wing flapping and jumps into the air. This dance has
intrigued people and led to attempts to imitate this dance by First Nation
dancers, as well as people from other cultures.
Sandhill
Cranes pair for life, which can be decades. The oldest crane, according to
banding records, was 36 years and 7 months. They tend to be faithful to their
nest site and will often use the same nest with another mate if their first mate
dies.
Sandhill
Cranes typically lay two eggs, but only raise one chick per year. The youngsters
leave the nest a few hours after hatching, but stay with their parents for nine
or ten months. The young ones are turned out of the territory the following
spring.
Most
Sandhill Cranes are 7 years old before their first nesting. Immature birds
often gather in loose flocks until they are ready to breed.
While
their diet is heavy in seeds and cultivated grains, Sandhill Cranes also eat adult
and larval insects, snails, reptiles, amphibians, nestling birds, small
mammals, seeds, and berries. They feed on land or in shallow marshes. They
winter in the southern U.S. and Mexico, preferring to spend the night roosting
in shallow lakes or rivers and foraging in the daytime in grasslands and
pastures.
Perhaps
readers will be fortunate enough to come across this big bird around the edges
of the marshes adjacent to Rice Lake and the Trent system.
