Mississippi Sandhill Crane Biology

Crane Biology

The Crane Family

Cranes are one of the most unique and spectacular of members of the bird family. Famed naturalist and pioneering wildlife biologist Aldo Leopold described cranes as, "nobility in the midst of mediocrity."

There are 15 species of cranes in the world, found on all continents except South America and Antarctica. Besides being one of the most interesting bird families, cranes are among the most endangered.

Eleven of the 15 species of cranes are considered at risk of extinction. Two crane species are found in North America, the endangered whooping crane and the wide-ranging sandhill cranes.

There are six different geographic types or subspecies of the sandhill cranes, all of which are uniformly gray in color with a carmine (or red) unfeathered crown and a white cheek patch.

Three are migratory subspecies, breeding in the northern United States and Canada and wintering in the southern United States and Mexico.

Three are non-migratory subspecies: the threatened Florida sandhill, endangered Cuban sandhill and the endangered Mississippi sandhill.

A Distinct Subspecies: The Mississippi Sandhill Crane

The Mississippi sandhill crane was described as a distinct subspecies in 1972 and there are physiological, morphological, behavioral and other differences between them and other sandhill cranes.

The Mississippi sandhill crane is a noticeably darker shade of gray resulting in a more distinct white cheek patch. Despite the limited number of breeding pairs in the wild population, electrophoretic studies indicate a reasonable level of genetic diversity.

These studies also show that the MS sandhill cranes posess one gene that is unique to sandhills and another that is different from even the Florida sandhill cranes.

The Mississippi and Florida sandhill cranes were listed as rare in the 1968 list of Rare and Endangered Wildlife of the United States. After being described as a separate subspecies, the Mississippi sandhill cranes were added to the United States' List of Endangered Fish and Wildlife on June 4, 1973. Jake Valentine wrote the first Recovery Plan in 1976; the third and final revision of the recovery plan was issued in 1991.

Mississippi sandhill cranes (Grus canadensis pulla) are a critically endangered subspecies found nowhere else on earth in the wild but on and adjacent to the Mississippi Sandhill Crane National Wildlife Refuge. There are only about 110 individuals remaining, including about 20-25 breeding pairs.

A Year in the Life of a Mississippi Sandhill Crane

 During the late fall/early winter, unpaired cranes forge new pair bonds and establish their territory. Mated for life, established pairs are in a "courting phase" throughout winter where their bonds are reinforced and they prepare for nesting season.

In late winter/early spring pairs generally lay two eggs. Both parents work together to incubate the eggs for about a month. This can be a precarious time for the nest, as there are many predators that are eager to make a meal of the eggs.

In spring, the precocial Mississippi sandhill colts (chicks) are hatched. The colts are feathered and able to walk around soon after birth.

Young cranes are able to fly after about 70-80 days. The juveniles will remain with their parents for about about ten months, after which they will venture out on their own and eventually form a pair bond.

A Case of Mistaken Identity

The most common case of mistaken identity on the refuge occurs between Mississippi sandhill cranes and great blue herons.

Cranes look superficially like herons and their relatives. Both are tall, thin, and have long legs, necks and beaks. The dark blue-grey color of the Mississippi sandhill's plumage is also similar in color to the plumage of a great blue heron. Despite their appearance, though, cranes are not closely related to herons, and their biology and way of living is quite different.

Check out the following fact sheet to learn more about how to spot the differences between the Mississippi sandhill crane and the great blue heron.

 

Mississippi Sandhill Cranes in Decline

The cranes are in decline primarily due to habitat loss. The original range of this population was thought to extend along the Gulf coastal plain from southern Louisiana east into Mississippi, Alabama, and into the western Florida panhandle.

Their range probably followed that of their habitat, the wet pine savanna. As this habitat was destroyed and degraded, the population declined. The last breeding records for Louisiana are from the 1910s and Alabama from 1960.

Much of the loss of crane habitat is due to the conversion of open pine savanna to pine plantations created following World War II. Habitat decline is also caused by suppression of the natural fire regime, degrading the savanna.

With air conditioning, rising living standards, and interstate construction, thousands of people moved to the Mississippi Gulf Coast to live and visit. The habitat was divided and subdivided until the refuge is now only small islands surrounded by human-altered landscapes. Cranes have also been directly harassed, shot, and may even suffer the effects of environmental contaminants.

Mississippi Sandhill Crane Species Profile 

Mississippi Sandhill Crane Recovery