Everyone loves the outsider, and when it comes to birds, there aren’t any bigger in North America than the whooping crane.
Until just 15 adults in 1938, whooping cranes returned from the brink of extinction. Although still at a precarious level, there are now around 900 captive birds and three wild populations.
The majority of the birds, over 500, are expected to end their fall migration from their breeding grounds in Alberta, in Wood Buffalo National Park in Canada, to the Texas coast where they will remain until the end of March.
“In our last winter estimate, we calculated the population for the penultimate winter because we couldn’t count last year due to COVID, at 506,” said Wade Harrell, recovery coordinator whooping crane from the US Fish and Wildlife Service. “We are quite sure that the population has increased since then. “
Harrell said the population expansion forecast is based on this summer’s nest count in which 102 nests were seen in Canada and 50 chicks are believed to have survived. Harrell said it was the first time the number of nests has exceeded 100.
In addition to the birds known as the western flock, which winter in Texas, New Mexico, and Mexico, there is also an eastern population, most of which nests in Wisconsin and winters in Florida, and a non-migrating flock in Louisiana. The eastern population began in 2001, started with pen-raised birds reintroduced into the wild. There are only about 75 birds in this population.
The Louisiana population began in 2011 using enclosure reared birds as well. There were over 70 birds at the last count.
“The reason we reintroduced birds to Louisiana was that there was a historic population, but they went extinct in the 1940s. They seem to be doing pretty well,” Harrell said.
He explained that due to the lack of protection and the loss of some birds and the decimation of habitat by hurricanes, Louisiana’s population has shrunk to a single bird. Efforts were made to transplant the bird to Aransas in 1950 in the hopes that it would assimilate into the wintering Texas flock, but it did not work.
The rest of the birds alive today are kept in captivity as a stock to add birds to the eastern and Louisiana population.
Historically, there have never been many whooping cranes in North America. Biologists estimate the population to be around 10,000 people. In comparison, Texas winters about 700,000 sandhill cranes, the only other species of crane in North America. Sandhill cranes can be hunted with hunters required to have both a state hunting license and a federal crane license.
Besides a difference in size, the dunes are about a foot shorter than the 5 foot tall whooping cranes, sandhill cranes use a greater diversity of habitats.
“I think the dunes are more of a general habitat species. They seem to have adapted better to modern agriculture. Whoopers need high-quality wetlands more, although we see migrating whoopers using agriculture in drylands, ”Harrell explained.
And this specific need for habitat is another potential attack on whooping cranes as Texas coastal wetlands disappear. While the Aransas refuge is best known as the winter home of the cranes, Harrell said at least half of the birds coming to Texas depend on private property or other sites.
Considering that only about 180 of the birds were migrating to Texas at the turn of this century, the recovery must be considered a success.
“Our population migrating through the central plains is increasing by around 4% per year. For a long-lived, slow-breeding species, recovery is slow but steady, ”explained Harrell.
A monogamous species, whooping cranes don’t become sexually mature until they are 4 or 5 years old, and then typically only leave one chick every two years. Birds are known to live to their late thirties in the wild and to their mid-forties in captivity and often breed until their mid-twenties. This means that a pair could potentially produce 10 to 12 offspring in a lifetime.
With numbers as low as they have become, the loss of a single bird for any reason is magnified and can slow the overall recovery of the species.
“We did some population modeling and, at best, it looks like the wild wintering population arriving in Texas could double from the current size within 20 to 25 years,” said Harrell.
Unlike the birds of Texas which are primarily migratory, the Louisiana population remains in the coastal marshes year round. Their recovery is happening at a slower pace.
“It’s a smaller, younger population and isn’t quite increasing at the rate of growth of the wild population. He’s going to need some help along the way. We’ll have to help with some captive-bred chicks.” , said Harrell.
Biologists don’t know why members of a species don’t migrate, but the most logical explanation is that all of their needs are met in one place and don’t need to expend energy to migrate.
In 2021, two breeding pairs of Louisiana whoopers attempted to nest on private property in Chambers, Jefferson Counties. Although their efforts failed, they are believed to be the first breeding pairs in Texas since the late 1800s.