The annual congregation of the Sandhill Cranes is one of the most beautiful natural phenomena in the United States.
For about a month every March, more than 500,000 Sandhill Cranes come together on the Platte River basin in Nebraska to rest and eat before finishing their migration to their northern breeding grounds.
This time on the Platte River not only gives the birds a chance to eat corn from the grain fields and take naps on the sandbars, but also gives them a chance to find a mate.
Below, we’ll take a closer look at one of the most common crane species in the world. We’ll be talking about their diet, breeding habits, as well as their conservation status.
Sandhill Cranes are large birds and have long, thin legs and necks. Their cheeks are white, but their most notable feature is the bright red patch on its forehead.
Sandhill Cranes are about three to four feet tall (0.9 to 1.2 meters), and have a wingspan that can easily be over five feet (1.5 meters).
Male vs Female
Sandhill Crane males are slightly larger than females, and can weigh up to 14lbs (6.3kg). Meanwhile females tend to weigh around 10lbs (4.5kg). The male is often usually a couple of inches taller than the female.
Are they aggressive?
There have been rare instances of cranes pecking people, and they have also been known to damage window screens as well as inflict other types of property damage.
This is probably due to the birds seeing their reflection, which distresses them and brings out territorial defense behaviors. This can lead to them scratching windows or other shiny, reflective surfaces.
Some farmers have also had difficulty with Sandhill Cranes damaging their crops while probing the farm fields for corn and other seeds. However, scientists have developed treatments for framers to put on their seeds to deter the Sandhill Cranes.
Still, Sandhill Cranes are popular with birdwatchers, especially during migration and courtship rituals.
What adaptations do they have?
The Sandhill Crane has a trachea that loops like a saxophone rather than being a straight tube. This is so the birds can emit their famously ear-shattering call that can be heard for over a mile.
They also have long, narrow legs that help them to wade in shallow water.
Sandhill Cranes mate for life, forming pair bonds that last until one of the birds dies. After their mate passes away, the surviving crane will look for a new mate.
Single Sandhill Cranes will start pairing up in the early spring, as the birds are migrating to their breeding grounds. This is when the birds will be at their loudest, as males and females will perform unison calling to create a bond.
During mating they will also perform dancing displays. Although the dancing is most common in the breeding seasons, the birds will actually dance all year long!
The dance can involve wing-flapping, bowing, and jumping, and they may sometimes throw a stick or some plants into the air.
When a pair reaches the northern breeding grounds they will mate and build a nest out of plant materials. The female will often lay two eggs, and she and the male will take care of the nest together.
The male takes on a protective role, standing guard and on the alert for predators.
It takes about a month for the eggs to hatch, and over two months for the chicks to become independent. In the fall, the younger cranes will migrate south with their parents. Cranes reach sexual maturity in two years and will then begin the search for their own mates.
As we’ve already alluded to, Sandhill Cranes have a very distinctive and interesting call. Both males and females will make a rattling ‘kar-r-r-r-o-o-o’ sound.
What do they eat? (Diet)
Sandhill Cranes are omnivorous and are opportunistic feeders, adapting their diet depending on what’s available. They will often eat plants and grains, but they also enjoy invertebrates and even small mammals, amphibians, and reptiles.
These can be rodents, snails, frogs, lizards, snakes and nestling birds, as well as vegetation such as aquatic plants, berries, and seeds. Their diet also varies due to the season.
Where do they live? (Habitat)
Sandhill Cranes spend most of their lives in freshwater wetlands like marshes, wet grasslands, and river basins.
Three subpopulations of Sandhill Cranes migrate. These are the lesser, greater, and Canadian Sandhill Cranes. These subspecies spend their winters in the south and summers at their breeding grounds.
What are their nesting habits?
Sandhill Cranes nest among marsh vegetation in shallow water up to 3 inches (7cm) deep, or they’ll sometimes nest on dry ground close to water.
The male and the female will build their nests, made of plant material pulled up from around the site. The nest may be built up from the bottom, or it may be floating or anchored to standing plants.
How long do they live? (Lifespan)
While Sandhill Cranes in the wild are more likely to die young, Sandhill Cranes are known to live for 20 years or more.
What predators do they have?
As a ground-dwelling species, Sandhill Cranes are at risk from predators and these are the biggest sources of mortality among the birds.
Raccoons, foxes, coyotes, wolves, cougars, and bobcats and lynx are their main predators, with the first three mainly hunting young cranes and the four latter predators are more likely to attack adult cranes.
Meanwhile other birds like ravens, crows and gulls are likely to feed on young cranes and eggs. Cranes of all ages are hunted by North American species of eagles. Great-horned owls may also hunt chicks.
In Oregon and California, the biggest predator of young cranes are golden eagles and bobcats, while the biggest predators of chicks in this area are raccoons, coyotes, and ravens.
Meanwhile in Cuba and Florida, crocodiles and alligators prey on Sandhill Cranes, especially recent fledglings.
Sandhill Cranes defend themselves and their young from aerial predators by jumping and kicking. Brooding adults are more likely to react aggressively to potential predators than wintering birds.
This is because they need to defend their eggs and chicks. Wintering cranes will often try to evade attacks on foot or in flight.
Meanwhile, for land predators such as raccoons, foxes and coyotes, Sandhill Cranes will defend themselves by moving forward, often hissing, with their wings outstretched and their bills pointed.
If that doesn’t deter the predator initially, the crane will stab the predator with its bill (this is powerful enough to pierce the skull of a small carnivore), and it will also kick.
What are their feathers like?
Sandhill Cranes have mainly gray feathers, but this shade of gray can vary widely. But while their feathers are gray, they can sometimes have a reddish-brown appearance.
This is because Sandhill Cranes preen themselves by rubbing mud on their feathers, and mud that is rich in iron is often red.
What does their poop look like?
Sandhill Cranes usually produce small, brown, round droppings.
Do they migrate?
Yes, they do migrate.
The cranes spend the winter in Arizona, California, Mexico, New Mexico, and Texas before migrating to their breeding grounds in early spring.
During the spring, the cranes can be seen resting and feeding along rivers and wetlands throughout the Great Plains and Pacific Northwest. The largest congregation of Sandhill Cranes occurs from February to early April along the Platte River in Nebraska.
Meanwhile in the late spring and early fall, Sandhill Cranes can be found at their breeding grounds. Some breed in Michigan, Minnesota and Wisconsin, while others breed in Alaska, Idaho, and Oregon.
Three subpopulations of Sandhill Cranes do not migrate, however. The Mississippi Sandhill Crane can be found on the southeastern coast of Mississippi.
Meanwhile, Florida Sandhill Cranes live in the many inland wetlands of Florida, and the Cuban Sandhill Crane live exclusively in the savannas, wetlands, and grasslands of Cuba. Both the Cuban and Mississippi Sandhill Cranes are critically endangered.
The biggest threats facing Sandhill Cranes are habitat loss, wetland loss, and development.
The Mississippi Sandhill Crane and the Cuban Sandhill Crane are federally listed as endangered on the Endangered Species List.
Sandhill Cranes have the nickname ‘Watchmen of the Swamp.’ This is because while they’re on the ground eating, they will keep an eye out for predators and if they spot danger, they will emit a loud alarm to call to warn their fellow cranes.
Sandhill Crane chicks are also called ‘colts.’
Sandhill Crane chicks are ready to leave the nest and can even start swimming within 8 hours of hatching. Although the chicks are independently mobile, they will stay with their parents up to 10 months after being born.
The oldest known fossil of a Sandhill Crane was found in the Macasphalt Shell Pit in Florida and is estimated to be 2.5 million years old.
During migration, Sandhill Cranes can travel more than 200 miles (about 321km) a day. They’re also fast fliers, able to reach speeds of up to 35 miles per hour (56kph).