Migratory Behavior of Whooping Cranes.

mirgratory behavior of whooping cranes
Two adult Whooping Cranes in flight. ~Chuck Hardin

Probably less than a dozen persons in the past 50 years have actually witnessed the northward departure of whooping cranes (Grus Americana) from their wintering grounds on and adjacent to the Aransas National Wildlife Refuge on the Gulf Coast of Texas. Few, if any, have observed a more spectacular exodus than the junior author watched on the morning of 6 April 1966.

On this clear, sunlit day he was conducting a combination routine and spring whooping crane departure date patrol through traditional crane habitat along the east shore road of the refuge. While traveling southwesterly one-half mile north of the northeast corner of whooper feed plot No. 1, he counted 32 of the giant birds within this managed crane feeding area. When he was about 1,000 yards from the cranes, 12 of them arose and flew eastward about one mile and lit along the northwest edge of Sundown (Mullet) Bay. While watching the 12 birds alight, he heard the obstreperous calling of most or all of the remaining cranes and turned to see that these birds had taken to the air. It became apparent later that they were en route to their remote northern nesting area.

Migratory behavior

Shortly after taking to the air, the flock quickly divided into groups of 3, 3, 2, 7, and 5 birds and circled clockwise, upward, and northward in a spiraling motion. The groups of 7 and 5 birds were thought to be yearlings and non-breeders. The remaining groups were family units. The horizontal and vertical separation of the individual groups varied and was estimated to range from 400 to 1,200 feet. The diameter of the circle was judged to be one-fourth mile.

The 20 cranes left the ground at 9:00 am; 12 minutes later they were only visible as tiny airborne specks, and in a few more moments they were no longer discernible through a 7 X 50 binocular.

Winds at the time of departure were from the southeast at about 18-20 mph. Each turn of a group of cranes into the wind resulted in a gain in altitude. As the birds spiraled upward, they maintained their respective positions with no noticeable change in the size or shape of the spiral. They “whooped” continuously as they moved upward and away from the observer. At no time were the 12 birds remaining on the ground heard calling.

Departure observed

Earlier that morning Benham had observed one immature and two adult whooping cranes feeding inside whooper feeding plot No. 2, approximately one mile north of the main body of birds. They had not flown as he passed about 1,500 feet from them. On his return past this spot he noted the three cranes about 500 feet off the ground, spiraling and calling loudly in a manner similar to the previously departed birds. The time was 9:14 am. At 9:19 am, Benham lowered the binoculars to rest his eyes. When the three cranes were last seen, they appeared larger than the 20 birds at last glimpse, so it is possible constant surveillance with the binoculars would have rendered the trio visible for longer than five minutes.

It is reasonable to assume calls of the first departing cranes were heard by the later migrating family because of wind direction, audibility of the cranes’ piercing whoops, and the close distance between the two groups when the airborne flock flew over or within one-half mile or less of the family unit. We hypothesize that the exodus of the 20 birds precipitated the departure of the lone family group.

It is interesting that the first contingent of migrating cranes displayed some aerial territorialism, although they were all observed feeding side by side within the food plot a few minutes before departure.—Robert H. Shields, Bureau of Sport Fisheries and Wildlife, Portland, Oregon, and Earl L. Benham, Bureau of Sport Fisheries and Wildlife, Austwell, Texas.

[The Auk, April-June 1968, Volume 85, Number 2, Page 318]

 

 

 

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Will Bugles Blow No More?

James Osborne Stevenson became the first refuge manager of the Aransas National Wildlife Refuge in Texas under the Bureau of Biological Survey. There he spent much of his time observing, studying, and photographing whooping cranes. He took the first ever color films of their courtship dances, and published a number of scientific and public interest articles on these cranes. In 1943, he published an article called Will Bugles Blow No More? about their endangerment. Jim died of a stroke on October 14, 1991. ~ Pam Bates

Will Bugles Blow No More?

BACK IN 1937, the boys used to gather around the old coal burner in Cap Daniel’s store at Austwell, Texas, commenting from time to time on the fate of the farmer. A visitor could have heard them mulling over the latest news: “I hear the government is buying up ‘the Blackjacks’ for a pile of money just to protect a couple of them squawking cranes! They tell me they ain’t bad eating but there’s no open season on them.” To this came the inevitable reply: “If you can’t shoot them, what the good are they?”

FACTS ARE INVARIABLY garbled in any hot-stove league. The Blackjack Peninsula, lying on the Gulf Coast of south Texas, near Austwell, was purchased as a national wildlife refuge not only to protect a remnant of the endangered whooping crane but also waterfowl, upland game and big-game animals. The Aransas National Wildlife Refuge, administered by the Fish and Wildlife Service, also furnishes feeding grounds for such fine waders as reddish, snowy and American egrets, Louisiana herons and the rare roseate spoonbill. These birds nest on the nearby Second Chain of Islands in San Antonio Bay, a sanctuary guarded by the National Audubon Society.

HEART-SHAPED, THE peninsula is fringed with salt marshes which are dotted with brackish ponds and bayous. The gently-rolling interior of the refuge is prairie-like, much of it covered with oak and sweet bay brush. There are scattered mottes or groves of large, windswept, gnarled live oaks, wrapped with mustang grapevines, and an undestory of mustang French mulberry  and  palmetto.

WHILE THE PURCHASE of this land for wildlife purposes was not made until 1937, it had served as a sanctuary since 1921. Mr. Leroy Denman, former owner and active conservationist, had protected wildlife on the area, and through his efforts herds of white-tailed deer and flocks of Rio Grande turkeys had increased tremendously. These animals still range through the mottes, parks and brushlands, together with the oft-persecuted peccary or javelina, native wild pig of the South-west.

OF THE 235 SPECIES of birds now known to have visited this 47,000-acre sanctuary, it was the whooping crane, largest of them all, that most intrigued me. Even before going to Texas, I anticipated seeing these birds on the refuge, one of their ancestral wintering grounds.

ONE LATE OCTOBER afternoon, shortly after I assumed my duties as manager of the Aransas Refuge, I accompanied some visiting officials on a tour of the area. At that time the roads were mere sand ruts cut through pasture land, winding, where necessary, to skirt “the brush.” As we came around a thicket into open grassland, we heard the guttural croaking of sand-hill cranes, alarmed at our approach.

Looking ahead, we saw about forty of these birds gathered around an artesian well. Our binoculars picked out from this group two stately white birds, much taller than their companions. How magnificent they were! Their plumage gleamed in the bright sunlight. We could see a carmine crown, forehead and lores, and a patch of red along the lower part of each cheek giving a walrus mustache effect. To watch these wary giants teeter from one foot to the other while awkwardly scanning the vicinity for danger was a never-to-be-forgotten experience. Here at last were those rare, beautiful, spectacular birds—the whooping cranes! All too soon they flew, revealing another distinctive marking, the black wing tips.

Will Bugles Blow No More?

EACH AUTUMN WHOOPING cranes come to this avian winter resort for a five or six-months’ vacation. Old-timers, who once owned small cattle ranches in the Blackjacks, told me that back in the ’70s and ’80s, hundreds of the big white birds were present from October to April. Their occasional raids on sweet potato patches near ranch-houses made them none too popular with housewives. Generally, though, they preferred to feed on shellfish and mullet, which they picked up in the salt marshes and ponds near St. Charles, San Antonio, or Mullet bays. The sand-hill crane, a much commoner bird, usually stayed inland on the prairies or in brush-lands. Mexican cowhands recognized this habitat preference of the whooper and, with their penchant for picturesque names, called it Viejo del Agua—the old man of the water.

MOST LOCAL NAMES are based on the color of this species or on its call notes. Adults are known as white cranes or Grulla Blanco; immature, cinnamon-colored birds as red cranes. One accepted name in Texas is bugle crane—since the loud piercing notes sound like a trumpet. But if you have ever heard a child’s intake of breath while suffering from whooping cough, you’ll know why the crane is called a whooper. Imagine the volume multiplied many times—and then crouch within thirty feet of the birds, as I have—the result is ear-splitting and blood-curdling. No wonder this war whoop can be heard at a distance of more than two miles!

FOR THREE WINTERS we kept careful count of the cranes on the refuge. In 1938-39 there were 10 adults and 4 immatures; the next winter 15 adults and 7 young; in 1940-41, 21 adults and 5 young—the largest population noted in recent years. We were inclined to consider this growth in numbers as a hopeful sign that the species was increasing until we realized that possibly it was due to “foreign” birds from the Louisiana marshes supplementing the usual wintering flock. The number of young birds which have been coming down from Canada with their parents each fall has been pitifully small. Although whoopers ordinarily lay two eggs, the hazards of hatching and rearing young birds were such that most parent birds, that had had any success in nesting, were accompanied by an “only child.” Very few family groups ever contained rusty-colored twins. Confronted with such low nesting success and survival, how can this species persist, let alone increase?

PERHAPS WHOOPING cranes could not have survived this long were it not for their natural wariness. They prefer broad expanses of prairie or open salt marsh permitting an unbroken view of the surroundings for miles around. On the refuge, they favor tho salt flats, lagoons and brackish bays where crabs and mollusks abound. Sometimes, birds venture into the brush in search of blackjack or live oak acorns, but bay flats are more to their liking and there they find greater safely. They feed in small groups, a few adults or a pair with its young. Immature birds are almost invariably flanked by their parents whose ever-watchful eyes scan the countryside on the lookout for signs of danger.

CRANES HAVE A CRAVING for fresh water and will fly long distances for a drink. In the fall of 1939, fresh water was at a premium and cranes frequented an artesian well on the refuge twice a day. Here was a chance for some close-ups of the birds! One day John Lynch, biologist with Fish and Wildlife Service, and I hopefully set out with Leica and movie camera to photograph one of the most difficult subjects in the American bird world.

WE SNEAKED UP to the well on hands and knees, collecting stinging nettles and grass burs all the way. Then as luck would have it, a cowboy flushed the cranes and geese resting there. Hiding in the corner of an old corral about fifty feet from an overflow pool near the well, we made a makeshift blind of boards and dead weeds while we waited. Two hours later, in came two groups of cranes—a family of three and a group of three adults. We expected a fight for we had noticed that family groups on the feeding grounds resented the intrusion of other cranes. However, a truce was called until all thirsts were satisfied. The male of the family group was not enthusiastic about the strangers but tolerated them. Flocks of Canada geese, widgeons and pintails flew in and lined up for water, awaiting their turn, but did not drink until the cranes had finished. The male of the family group took pokes at geese when they got “out of line,” and once he jabbed at another crane that got in his way. This bird, caught off guard, tripped and fell over a much surprised Canada goose resting nearby. We got our pictures—although we were more nervous than the birds!

Will Bugles Blow No More?

I WELL REMEMBER another memorable occasion. One April morning, patrolman Everett Beaty and I were on the east-shore flats trying to determine how many cranes remained of the winter’s population. The few birds we saw appeared nervous as though impatient to be off for their summer home in Canada. As we watched a feeding pair, the larger of the two suddenly approached its companion, jumped into the air with outstretched wings, then alighted and began to flutter his wings and bow. Could we believe our eyes? Yes, we were watching the first stages of the famous courtship dance of the whooper! This dance, if it can be dignified by such a term, never lasted more than a minute or so. It did, however, take place occasionally throughout the day between extended periods of feeding.

THIS STATELIEST OF birds loses all its dignity while courting. Picture, if you will, Ichabod Crane of Sleepy Hollow at a jitterbug contest. The male jumps into the air, beating his wings, then flutters about his mate. Sometimes he bows low, an ungainly curtsy, with head and body near the ground. While in a crouching position, his wings droop, he charges toward his mate, circling her and perhaps letting out a few whoops. At times both birds face each other, jumping up and down while their wings beat the air. Most of the dance is performed by the male, the hen playing the role of interested onlooker. She often acts coyly, blithely feeding while walking away from him. Then, if her mate’s ardor lags, she turns about and flies to him as though begging for more attention. This leads to more bowing and scraping on his part.

A LATE-STAYING FAMILY group, lingering on through May, in 1941, gave us the opportunity to observe how the young birds are treated during the season of courtship. It was comical to find that the young bird of this group, so jealously guarded during the previous winter by its parents, was an unwanted wallflower when the male asked his mate for a dance. At this season, the male had no use for his offspring and would threaten it every time it came near; the young bird then wandered off to feed alone. The pair couldn’t be blamed, of course, for wanting a little privacy for their wild hopping and ungainly antics which kept up until late June. After that, the courtship subsided, and the immature crane was allowed to rejoin the older couple. Although the birds remained on the refuge all that summer, it is doubtful whether they attempted to nest. We had hoped, of course, that the birds would nest on this southern refuge, a custom which, it is said, they practice in the Louisiana marshes. There, some cranes spend the year-round, and it is rumored by some persons, and sworn to by the Cajuns, that they have nested there for many years.

WHAT IS LEFT OF the flocks of thousands and thousands of whoopers that formerly crossed the Plains twice a year in passage between their nesting grounds of Canada and the Prairie states, and their winter home in Mexico and the Gulf region? A sorry remnant at best—probably not more than two hundred birds. They formerly wintered by the hundreds in the lagoon country of northeastern Mexico, but none has been reported from that region in recent years. As far as is known, the only important wintering grounds are now those in the White Lake region of southern Louisiana, and in the Aransas Refuge and vicinity on the south coast of Texas. It so happens that only 15 birds (13 adults and 2 immatures) spent the winter of 1941-42 on the refuge; and persons who searched the Texas bays and marshes for other groups were unsuccessful.

EVEN ON THESE coastal marshes, once a safe haven for wintering cranes, the birds were threatened. Bombing and machine-gun ranges for Army Air Corps use have been created on the barrier islands because “the areas are isolated and comparatively few people will be affected by their use.” Cranes, unfortunately, have not yet come to fear the target shooting boatmen on the Intra-coastal Waterway which invades the heart of their feeding grounds. Exploration for oil and the drilling of wells in the marshlands and bays also continue. Are the birds to be driven from their last stronghold ?

IN THE PAST, some toll of cranes was taken by angry farmers of the Great Plains who resented the birds’ fondness for sprouting wheat. No doubt others were killed simply out of curiosity—the fate of many a large, spectacular species. On the prairies of central Texas, a favorite stopping point in migration, cranes were once held in favor as birds for the pot. According to John K. Strecker, the noted Texas ornithologist, the whooper was a favorite game fowl in McLennan County, Texas, in the middle of the last century. “It was only after the wild turkey, prairie chicken and whooping crane began to become scarce,” he wrote, “that the bobwhite came into repute as a game bird.” (Quail must have been considered small fry in those days!)

MARKET HUNTERS IN Texas did kill and sell some whoopers but favored the sand-hill, a vegetarian, as a better tasting bird. The bugle crane was considered inferior because “it ate sea food and tasted fishy.” However, ranchers in the Blackjacks did vary their diet of frijoles and sowbelly with crane meat. One man, knowing of my interest in the species, assured me that his family never shot more than one every week or so. He then., added as an after-thought: “I wonder where they all went to?”

PERSECUTION BY MAN and reduction in nesting areas due to drought and drainage, has brought the species to a low point from which it may never recover. Probably some of the adults we now find are old, sterile birds incapable of producing young. There are few of them left and the gauntlet they fly twice each year is a hazardous one. True, they are protected by international treaties and some help is given them on wintering grounds, but little pot-shooting here and there could easily wipe out this conspicuous bird.

IS THE OLD WHOOPER doomed? What can be done to help this bird ? For one thing, we need a complete life history study that will point out the specific requirements to save this species from oblivion. This approach to the problem is fundamental; it has already been used by the National Audubon Society in the case of the roseate spoonbill and the ivory-billed woodpecker. We know there is need for additional patrol, for an educational campaign to be carried out in the vicinity of the birds’ wintering grounds. The Canadian breeding grounds are now mainly restricted to southern Mackenzie and northern Saskatchewan, and possibly sections of Alberta; however, the exact location of nesting areas is shrouded in mystery. The summer homes of these cranes must be found and a study made to determine factors limiting nesting success and rearing of young. The information will be basic to wise conservation and management. Possibilities for a refuge on the resting grounds in Nebraska where the birds stop in migration are now being explored. It will be necessary for conservationists to muster every available resource in the last faint hope of saving this crane.

MAY THE OLD WHOOPER continue to trumpet down through the years! Though the outlook for his survival is dark, may the day never come when the last bugler blows taps for his race. ~ James Osborne Stevenson, 1943

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Whooping Crane Festival at Port Aransas, TX

 

 

 

 

 

 

 

WCF 2014 News header
Welcome to the Whooping Crane Festival
Come Whoop It Up at our 18th Annual Whooping Crane Festival! Join us February 20-23, 2014 for a weekend full of all things ‘birdy’!
Early registration closes February 10. Register today by clicking here!

BREAKING NEWS
Guest Speaker Added to Festival Line-up Attendees at the Whooping Crane Festival in Port Aransas will learn even more about the endangered species this year! For the first time in the festival’s eighteen year history, the superintendent of Wood Buffalo National Park in Canada will be one of the featured speakers.  Rob Kent, who oversees the nesting grounds of the cranes, will give a special presentation on Friday evening, February 21, at UTMSI. With aerial discovery in 1954 of the cranes nesting within Wood Buffalo National Park, advocates of the Whooping Crane were elated. The mystery had been solved as to where the cranes were nesting and that they were already in a protected area. Don’t miss this presentation on the protection and recovery from the nesting grounds in WBNP.
Raffle Tickets Now Available!  

Be sure to purchase tickets for our awesome raffle this year ~ benefitting the conservation of Whooping Cranes!

  • Vortex Viper HD 20-60X80 Spotting Scope & Pro GT Series Tripod
  • Ranger 8×42 Binoculars
  • Migration Tour w/lunch for 2 at Fennessey Ranch
  • 8-9 Hour Deep Sea Fishing Trip for 2 – Fisherman’s Wharf
  • Dolphin Watch Trip for 2 – Island Queen
  • “Wildlife in Focus VI” Books – Fennessey Ranch
  • $100 H-E-B Gift Certificate
Stop by our Visitors Center now to purchase your raffle tickets. The Chamber will also be selling raffle tickets and our 2014 festival T-Shirt at the Bird’s Nest Trade Show.
Stay up to date on the festival excitement by checking us out on Facebook, Twitter and our website!
Stay & play in ‘Port A!’
‘Port A’ Nature Video
Port Aransas, Texas ~ Naturally Fun!
Port Aransas, Texas ~ Naturally Fun!
Festival Updates
January 2014

Festival Speakers

Local expert birder, Mel Cooksey, will be a guest speaker discussing shorebirds at this year’s festival. Additional presenters will discuss the Eastern Partnership, the Reintroduction of Whooping Cranes to Louisiana, and Are Birds and Humans Different?, among other interesting subjects.

Birding at La Copita
The Festival offers a wonderful post-festival trip to birdwatch at

La Copita Ranch. This morning excursion wraps up the fantastic birding opportunities that we offer during the festival. Check it out!

Photography Workshops

Larry Ditto’s photography workshops and trips are filling fast. Reserve your space today!

In The News
Endangered Whooping Cranes taught to migrate south behind an ultralight plane! Click here to watch the story.

Quick Links


facebook Follow us on Twitter  View our videos on YouTube

 www.whoopingcranefestival.org   800-45-COAST  | (361) 749-5919
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Whooping Crane Recovery Plan – March 2007

Friends of the Wild Whoopers often receives questions about the status and long-term plans for managing whooping cranes. To provide you with the best answers we have posted a copy of the preface and executive summary of the official International Recovery Plan for the Whooping Crane. If you do not find the information you seek, then you can click on the link provided to see a copy of the entire plan.

Sixteen Whooping Cranes photo by Mike-Umscheid
Sixteen Whooping Cranes photo by Mike-Umscheid

   International Recovery Plan

     for the Whooping Crane 

   March 2007 – 3rd Revision

 

Prepared by: Canadian Wildlife Service and U.S. Fish and Wildlife Service

 

 

 To see the total 163-page PDF File click on:    the entire Recovery Plan

PREFACE

The Whooping Crane Recovery Plan (Plan) was prepared under the authorities of the U.S. Endangered Species Act (ESA) of 1973, as amended, the Canada Wildlife Act of 1974, and the Canadian Species at Risk Act of 2003. Decision-makers are provided with an orderly set of events that, if carried to successful completion, will change the status of this species from the Endangered to the Threatened level. The Plan describes management and research actions that are underway and proposes additional actions needed to ensure the recovery of the whooping crane. Funding levels and time schedules are estimated, and priorities have been set for each management and research action. This revision of the Whooping Crane Recovery Plan describes recovery actions and costs required for the birds and habitat in both Canada and the United States. Part I covers basic biology of the species, historical and present distribution, habitat requirements, numbers and rate of growth, biological factors limiting the population, human threats, and conservation measures. Part II states the recovery goals, strategy, objectives and criteria, provides a step-down outline of specific actions needed for recovery, and describes protective actions to alleviate threats. Part III provides an implementation schedule for recovery.

Parts IV and V provide contact information and key references. Appendices C and D, respectively, address recovery actions completed or underway, and summarize responses to public comments on the draft plan.

The recovery program for the whooping crane is an excellent example of international cooperation to save a species. Cooperative recovery actions of the 2 nations are outlined in a Memorandum of Understanding on the Conservation of the Whooping Crane approved in 1991 and updated at 5-year intervals. Development of this Plan by a joint Canada/U.S. Recovery Team is appropriate because the whooping crane’s recovery is dependent upon conservation and management of the species in both countries.

As an international document, the Plan has a unique format to satisfy the requirements of both Canada and the United States. It was written in conjunction with 2 Canadian documents; National Recovery Strategy for the Whooping Crane (Grus americana) and Action Plan for the Whooping Crane (Johns and Stehn 2005a,b).

EXECUTIVE SUMMARY

Current Status and Distribution: In the United States, the whooping crane (Grus americana) was listed as threatened with extinction in 1967 and endangered in 1970 – both listings were “grandfathered” into the Endangered Species Act of 1973. Critical habitat was designated in 1978. In Canada the whooping crane was designated as endangered in 1978 by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and listed as endangered under the Species at Risk Act (SARA) in 2003. Critical habitat in Canada is officially designated upon publication of a final SARA Recovery Strategy or Action Plan on the SARA Public Registry.

Whooping cranes occur only in North America. They currently exist in the wild at 3 locations and in captivity at 9 sites. The February 2006 total wild population was estimated at 338. This includes: 215 individuals in the only self-sustaining Aransas-Wood Buffalo National Park Population (AWBP) that nests in Wood Buffalo National Park (WBNP) and adjacent areas in Canada and winters in coastal marshes in Texas; 59 captive-raised individuals released in an effort to establish a non-migratory Florida Population (FP) in central Florida; and 64 individuals introduced between 2001 and 2005 that migrate between Wisconsin and Florida in an eastern migratory population (EMP). The last remaining wild bird in the reintroduced Rocky Mountain Population (RMP) died in the spring, 2002. The captive population contained 135 birds in February, 2006, with annual production from the Calgary Zoo (CZ), International Crane Foundation (ICF), Patuxent Wildlife Research Center (PWRC), Species Survival Center (SSC), and the San Antonio Zoo (SAZ). The total population of wild and captive whooping cranes in February, 2006, was 473.

Habitat Requirements:

 
The whooping crane breeds, migrates, winters, and forages in a variety of habitats, including coastal marshes and estuaries, inland marshes, lakes, ponds, wet meadows and rivers, and agricultural fields.

Reasons for Listing and Limiting Factors:


Historic population declines resulted from habitat destruction, shooting, and displacement by activities of man. Current threats include limited genetics of the population, loss and degradation of migration stopover habitat, construction of additional power lines, degradation of coastal ecosystems, and threat of chemical spills in Texas.

Recovery Goal:

The recovery goal is to establish multiple self-sustaining populations of whooping cranes in the wild in North America, allowing initially for reclassification to threatened status and, ultimately, removal from the List of Threatened and Endangered Species (delisting). Populations may be migratory or non-migratory.

Recovery Strategy: 

The wild whooping crane population is characterized by low numbers, slow reproductive potential, and limited genetic diversity. A stochastic, catastrophic event could eliminate the wild, self-sustaining Aransas-Wood Buffalo population (AWBP). Therefore, the recovery strategy involves: protection and enhancement of the breeding, migration, and wintering habitat for the AWBP to allow the wild flock to grow and reach ecological and genetic stability; reintroduction and establishment of self-sustaining wild flocks within the species’ historic range and that are geographically separate from the AWBP to ensure resilience to catastrophic events; and maintenance of a captive breeding flock to protect against extinction.

Offspring from the captive breeding population will be released into the wild to establish these populations. Production by released birds and their offspring will ultimately result in selfsustaining wild populations. The continued growth of the AWBP, establishment of additional populations, and maintenance of the captive flock will also address the loss of genetic diversity.

RECOVERY OBJECTIVES AND CRITERIA:

This plan sets forth 2 primary objectives and measurable criteria that will allow the species to be reclassified to threatened (downlisted). The numerical population criteria can only be achieved if threats to the species are sufficiently reduced or removed, i.e., the population criteria are a benchmark for threat reduction.

Objective 1 – Establish and maintain self-sustaining populations of whooping cranes in the wild that are genetically stable and resilient to stochastic environmental events.

Criterion 1 – Maintain a minimum of 40 productive pairs in the AWBP for at least 10 years, while managing for continued increase of the population. Establish a minimum of 25 productive pairs in self-sustaining populations at each of 2 other discrete locations. A productive pair is defined as a pair that nests regularly and has fledged offspring. The two additional populations may be migratory or non-migratory. Population targets are 160 in the AWBP, and 100 each in the Florida non-migratory population and the eastern migratory population. All 3 populations must be self-sustaining for a decade at the designated levels before downlisting could occur.

Alternative Criterion 1A – If only one additional wild self-sustaining population is reestablished, then the AWBP must reach 400 individuals (i.e. 100 productive pairs), and the new population must remain above 120 individuals (i.e. 30 productive pairs). Both populations must be self-sustaining for a decade at the designated levels before downlisting could occur. This alternative is based on the principle that with the reestablishment of only one additional population separate from the AWBP, then crane numbers must be higher in both populations than if there are three distinct populations.

Alternative Criterion 1B – If establishment of second and third wild self-sustaining populations is not successful, then the AWBP must be self-sustaining and remain above 1,000 individuals (i.e. 250 productive pairs) for downlisting to occur. The Memorandum of Understanding on Conservation of Whooping Cranes, approved by Canadian and U.S. federal officials, recognizes a goal of 1,000 individuals in the AWBP population. This higher number ensures a better chance for survival of the AWBP in the event of a catastrophic event within its extremely limited range. The target of 1,000 is reasonable for downlisting given the historical growth of the AWBP and theoretical considerations of minimum population viability. To ensure sufficient genetic variability, the AWBP must increase to the level where the creation of new alleles through genetic mutation will offset the loss of genetic diversity. After reaching the goal of 250 pairs, the population should gain genetic variation faster than the population loses genetic material.

Objective 2 – Maintain a genetically stable captive population to ensure against extinction of the species.

Criterion 2 – Maintain 153 whooping cranes in captivity (21 productive pairs). Genetic analysis suggests that 90% of the genetic material of the species can be sustained for 100 years at this population size (Jones and Lacy 2003). To achieve this, this Plan recommends having 50 captive breeder pairs of whooping cranes by 2010, including 15 pairs at PWRC, 12 at ICF, 10 at CZ, 10 at SSC, and 3 at SAZ. A breeder pair (as differentiated from a productive pair) is defined as a pair that breeds or is intended to breed in the future. Production from PWRC, ICF, CZ, SSC and SAZ will be the principal source of birds for release to the wild for reintroduced populations. However, sources of release birds should be based on the optimal genetic mix to ensure long-term population viability.

Delisting Criteria

Delisting criteria have not yet been established because the status and biology of the species dictate that considerable time is needed to reach downlisting goals. In addition, new threats are expected to arise and will have to be overcome before downlisting occurs. Additional information is also needed on the conservation biology of small populations, including a determination of effective population size (Ne) for whooping cranes to maintain genetic viability over the long-term, and impacts of stochastic and catastrophic events on population survival.

Actions Needed:

1. Continue to build the AWBP and protect and manage its habitat to minimize the probability that a catastrophic event will eradicate this population.

2. Attain breeder pair and productivity goals at 4 captive facilities in the United States and 1 in Canada to produce the birds required for reintroductions. Continue research to improve production of captive flocks.

3. Establish 2 additional self-sustaining wild populations. Continue research to identify appropriate reintroduction sites and improve reintroduction techniques. Protect and manage habitat of reintroduced populations.

4. Continue to use genetic information and advances in conservation biology to conserve flock genetics, and determine Ne and revise criteria as warranted.

5. Maintain an outreach program.

Date of Recovery: The estimated time to achieve downlisting is the year 2035. At current rates of reintroduction it takes over 10 years to build a population of more than 100 individuals. These individuals must then reach breeding age (3-5 years) and produce enough young to become selfsustaining for a decade to meet criteria for downlisting. This is expected to take a minimum of 30 years. New information gathered through recovery actions will be incorporated into additional population viability analyses as the population approaches its downlisting goals.

Delisting criteria will be established at that time, and the overall recovery strategy and actions will be revised as appropriate.

Total Estimated Cost of Recovery ($000s):

The current budget expenditures needed annually for recovery are $6.1 million (US). The cost through 2010 is estimated at just over $30 million (US) and nearly $126 million (US) through 2035.

2006 1394 1705 3030 0 15 6144
2007 1388.25 1705 3042.5 30 15 6180.75
2008 1388.25 1705 3042.5 0 15 6150.75
2009 1388.25 1705 3042.5 0 15 6150.75
2010 1388.25 1705 3042.5 0 15 6150.75
2011 1419.8 1609 3045 0 15 6088.8
2012 1419.8 1609 3045 5 15 6093.8
2013 1419.8 1609 3045 0 15 6088.8
2014 1419.8 1609 3045 0 15 6088.8
2015 1419.8 1609 3045 5 15 6093.8
2016 1009 188 2025 0 6 3228
2017 1009 188 2025 0 6 3228
2018 1009 188 2025 0 6 3228
2019 1009 188 2025 0 6 3228
2020 1009 188 2025 0 6 3228
2021 1009 188 2025 0 6 3228
2022 1009 188 2025 5 6 3228
2023 1009 188 2025 0 6 3228
2024 1009 188 2025 0 6 3228
2025 1009 188 2025 0 6 3228
2026 1009 188 2025 0 6 3228
2027 1009 188 2025 0 6 3228
2028 1009 188 2025 0 6 3228
2029 1009 188 2025 0 6 3228
2030 1009 188 2025 0 6 3228
2031 1009 188 2025 0 6 3228
2032 1009 188 2025 5 6 3233
2033 1009 188 2025 0 6 3228
2034 1009 188 2025 0 6 3228
2035 1009 188 2025 0 6 3228
Total 34,226 20,330 70,925 50 270 125,801

Go here to view the entire Recovery Plan (163-page PDF File)

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