January: Catching Crabs
During January,
migratory cranes are on their wintering grounds. Feeding is their main activity. They must build up fat reserves to fuel the long flight back to the summer
nesting grounds. Whooper chicks are fed most of the winter by their parents. Learning how to eat blue crabs is important for juvenile cranes during their first winter in Texas or Florida. Blue crabs are not so easy to eat! When an adult catches a blue crab, Junior runs over and begs for an easy meal. Small crabs are swallowed whole. With a big crab, the adult usually carries it to the edge of a pond and pulverizes it on before feeding pieces to the youngster. An adult crane can eat up to 80 blue crabs in a day!
February: Courting and Pairing
By February, cranes on the wintering grounds are becoming more territorial and uneasy around other cranes. Their thoughts are turning to nesting season ahead. Pair formation begins when birds are two to three years old. Most cranes make their mate choice only once, so they want to get it right. They dance to attract a healthy, strong mate. The small population makes it urgent to choose a mate that can help raise babies throughout a lifetime. Dancing isn't only for first-time mates. Starting around Valentine's Day, long-established pairs dance to strengthen their bond.
March: Starting to Migrate
March brings restlessness to the wintering cranes as days get longer. The birds not raising families may now be northward bound. Cranes of the western flock that wintered in Texas could encounter dangerous weather if they left as early as the eastern flock from Florida. Birds heading to Canada must race for their nesting grounds where summers are short, but northern habitats may not be ready if they arrive too soon.
April: Returning to Nesting Grounds
April is the month of big departures from the Texas wintering grounds. It's also when many eastern cranes will already reach their Wisconsin nesting grounds. Whooping Cranes
migrate in small groups that leave at different times. These staggered departures help the species survive. The entire
flock would be in peril if all
the birds flew together and encountered a blizzard or tornadoes, or couldn't find food in ponds still covered with ice. The closer the families get to the nesting grounds, the more urgently the parents move. They must get back to lay eggs so the new chicks will have enough time to grow before fall migration. By the time the adults reach their familiar nesting territory, the "kids" are ready for independence. Some have already left Mom and Dad to hang out with subadult pals.
May: Nesting
In May, nesting gets underway for pairs on their summer breeding grounds. Crane parents are busy during the short northern summers. Once their territory has been established, the adult pair builds a nest for two eggs, laid a day apart. Pairs take turns incubating day and night for about 30 days. The babies usually hatch one day apart. Cranes usually can raise just one chick, but each year some families are able to raise both. Raising two chicks in a season is something to celebrate! Chicks develop quickly. In just a few days, they begin to venture away from the nest platform to forage and explore. Parents keep busy searching for snails, insects, and small fish to bring their chicks.
June: Growing and Learning
Crane babies may grow an inch a day between 10 and 30 days of age. They need long legs so they can follow parents in the tall grass. After that, their body growth slows. Adult feathers start to replace the fluffy coats of down. Parents stay close to teach and protect their young. The babies must be able to walk, swim in shallow water, and keep up with their parents, learning about food and dangers. They hop, run, and flap to build their flight muscles and gain endurance. North America's tallest bird has to grow fast: At five or six months of age, Whooping Crane babies must be ready to fly hundreds of miles with their parents on their first southward migration.
July: Growing Feathers for Flight
By July, the gangly chick's black wingtip flight feathers start to appear. Crane chicks usually fledge, or have the feathers necessary for flight, when they are about three months old. Crane feathers get lots of wear and tear. Soon after their chicks hatch, the parents also begin growing a new set of feathers. Once a year the adults shed their old feathers as strong, sturdy new ones grow in to replace them. The breeding season is the right time for adults to molt because the parents must stay close to their chicks until they can fly. Once able to fly, the young can better escape from predators. After their molt is complete, the adults are safer too. By fall, all the cranes will have sturdy flight feathers to withstand the long journey south.
August: Fueling Up and Flying
It's August and the juvenile's rusty brown feathers have mostly been replaced by white feathers, like those of the dazzling adults. His tawny color lets him blend in, so a predator would notice parents first. His mix of feathers tells other territorial cranes that he’s a youngster and they cut him some slack. The young cranes are starting to fly. Families and subadults fly off to forage in corn fields, meadows, wetlands and marshes. All cranes must build up body fat to fuel them on the coming migration. By the end of August, youngsters stand almost as tall as their 5-foot parents.
September: Taking Wing
By September, the chicks are flying. They practice flying with their parents, whether with real adult cranes or, from 2001 to 2015, with tiny aircraft and Operation Migration pilots wearing white costumes to hide their human forms. The parents are teaching a whole new set of skills that include flying, watching for danger from the air, and finding safe places to land. Days grow shorter as autumn arrives, and the cranes are getting restless. Parents want to move south after they’re done molting, but those with babies don’t want to rush them, so that may keep families behind on the nesting grounds for now.
October: Learning the Route
October is the month when the journey south begins. Whether they were born in Wisconsin (eastern flock) or Canada (western flock), baby cranes must be taught their migration route. In Wisconsin, crane chicks were hand raised each summer from 2001 to 2015 and trained to follow an ultralight airplane to learn their 1,280-mile migration route south to Florida, the wintering grounds for the eastern migratory flock. With a shorter journey south, adult cranes in the eastern flock can leave later than their northern Canadian-born cousins. Meanwhile, the larger western flock in Canada is already underway, as their migration to the Gulf Coast of Texas is twice as far as the eastern flock's to Florida. All the summer's babies learn not only the route between their summer and winter homes, but the preferred stopover sites as they're led on their first migration south. The youngsters need to fly the route only once to remember it for the rest of their lives.
November: Arriving on the Wintering Grounds
During November, cranes are arriving on their wintering grounds on the Gulf Coasts of Texas or Florida. The best winter habitat for cranes has marshes
where cranes can find lots of blue crabs, their most important
food. Each family wants to claim a prime place for finding blue crabs. Cranes will move to other territories if necessary to find food, but would rather hunker down. Crane parents must teach their young how to find and eat blue crabs, which don't exist on their northern nesting grounds. The juveniles stay with their parents throughout the winter. They learn the landscape of their wintering grounds and how to find food that's fit for cranes.
December: Settling into Winter
By December, Whooping Cranes are settled on their wintering grounds. The western flock overwinters on Aransas National Wildlife Refuge in Texas. The reintroduced eastern flock is mainly in Florida, with a few birds in nearby states such as Tennessee, Alabama, and South Carolina. This juvenile and its parents just arrived at Aransas after a 2,500-mile migration from Canada. The curious young crane has found a new plaything: a piece of seaweed on the shore of the Gulf of Mexico. It's a time of discovery as important and new as when he had just hatched in Canada. The watchful parents are always nearby, and happy to be back where they can find blue crabs to eat!
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