TPWD News Release — Dec. 6, 2004
Biologists at the Aransas National Wildlife Refuge completed a census flight on the Texas coast and tallied 216 birds recently. That number exceeds the previous high of 194 whoopers counted in the winter of 2003-04.
The whooper population that winters in Texas and nests in northwestern Canada reached a low of only 15 birds in 1941 when efforts to protect the species and its habitat were just beginning. The population has since been growing at about four percent annually.
Although the federal refuge and nearby state lands provide the historic nucleus of whooper wintering habitat, state biologists say private landowners play an important, if often overlooked, role in helping whoopers and other wildlife, since they manage and protect private property along the coastal bays and estuaries where whooping cranes winter.
This year’s increase in numbers is due to good nest production last summer. A total of 54 nesting pairs hatched 66 chicks on their nesting grounds in Wood Buffalo National Park, Canada, according to the Canadian Wildlife Service.
This year’s record population of 216 includes 33 young cranes that have completed their first migration to Texas. The 33 juvenile cranes, including two sets of twins, are the most to ever arrive at Aransas, three more than the previous record high of 30 juveniles in 1997.
Although the whooping crane population remains endangered, the comeback of the species sets a standard for conservation efforts in North America.
“It’s been a slow process for recovery of this species,” said Texas Parks and Wildlife Department Biologist Lee Ann Linam, who speaks from experience. Her father Frank Johnson managed the Aransas refuge when Linam was younger and helped to bring the population to the 100-bird mark in 1986. “It takes 3-5 years for a whooping crane to mature, and when they nest, they usually only produce one chick.”
“We were hoping for 200 whooping cranes in the year 2000, but the population went into a decline for a couple years before rebounding back to 194 cranes last winter. Getting a record-high count right around the Thanksgiving holiday is certainly something to be thankful for,” said Tom Stehn, U. S. Fish and Wildlife Service whooping crane coordinator at the Aransas refuge.
The whooping crane population continues to face many threats, including collisions with power lines during migration, limited genetic variability in the birds themselves, loss of crane migration habitat, and winter habitat threatened with loss of productivity due to reduced fresh water inflows and chemical spills.
Also, Linam notes, sandhill crane and snow goose hunters in Texas have a special responsibility in safeguarding whooping cranes that may still be migrating through Texas during hunting seasons. Hunters need to be able to recognize the difference between these similar-looking species. TPWD has posted a file on its Web site titled “Be Sure Before You Shoot,” which offers drawings and information to help hunters distinguish whooping cranes from game birds.
This sole natural wild population of whooping cranes nests in the Northwest Territories of Canada in summer and migrates 2,400 miles to winter at the Aransas and Matagorda Island National Wildlife Refuges and surrounding areas.
Their winter range stretches out over 35 miles of the Texas coast about 45 miles north of Corpus Christi. Wintering whooping cranes use salt marsh habitat foraging primarily for blue crabs. Unlike most other bird species, whooping cranes are territorial in both summer and winter and will defend and chase all other whooping cranes out of their estimated 350-acre territories.
Since whooping crane migration starts in mid-September and is usually not completed until mid-December, it is still possible that a few additional cranes will turn up to be counted on the weekly census flights conducted by the USFWS. It takes as many as eight hours of flying to cover the 55,600 acres of marsh over a 35-mile stretch of the Texas coast to find all the cranes. These flights determine the size of the total population, locate crane territories, and note any deaths that may have occurred.
“Counting every whooping crane every week is quite a challenge. We have thousands of other white birds in the marsh, including pelicans and egrets that make aerial spotting of cranes more difficult. Also, the cranes can move during a census flight and either not be counted or else be counted twice,” said Stehn.
During the last several decades, biologists have implemented several measures to try to bring whoopers back to the wild in other locations.
Since 1993, captive bred whooping cranes have been released annually in central Florida. Today, that non-migratory flock numbers approximately 75 birds. During the past three years, these cranes demonstrated their maturity by nesting and producing chicks on their own.
In addition, a migratory flock was established using an ultra light aircraft to teach the whooping cranes a migration route between Wisconsin and Florida. This migratory flock now numbers 49, with the cranes flying solo after being led on their initial trip across the eastern U.S. behind the aircraft.
This number includes 14 juvenile whooping cranes currently in Georgia being led by the migration team. The team of pilots and biologists assigned this task make up the Whooping Crane Eastern Partnership.
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