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2006 Notes of the SouNtOhReTaHsEtAeSrTEnR NN NaAtTuUrRaAlLiIsStT, Issue 6/3, 20103(71):39–42
An Unusual Journey of Non-migratory Whooping Cranes
Matthew A. Hayes1,*, Anne E. Lacy1, Jeb Barzen1, Sara E. Zimorski1, Kristin A.L.
Hall2, and Koji Suzuki3
Abstract - In 2000, an adult pair of non-migratory Grus americana (Whooping Crane) left
Florida and settled in Michigan for the summer. On 21 November, the pair left Michigan and
was radio-tracked south to the north shore of Lake Erie. The next day, only the female was
detected. She was tracked to Kissimmee Prairie, FL, her release site as a subadult. This female
flew from Michigan to Florida in 11 days, only stopping for 2 of those days. Her movement and
flight behavior approximated natural Whooping Crane migration behavior. That this adult
female could return to her release area and physiologically prepare for a long flight suggests
migration is both learned and innate. Our conclusions help refine reintroduction techniques
possible for migratory cranes.
Grus americana Linnaeus (Whooping Crane) faced extinction as recently as the
1940s (Allen 1952). At that time, a small migratory population was known to winter at
Aransas National Wildlife Refuge (ANWR) in Texas (Allen 1952), but the breeding
area of this flock remained unknown. When the breeding area was discovered at Wood
Buffalo National Park (WBNP) in Canada (Allen 1956), intensive conservation and
recovery plans were initiated to protect the migratory population’s breeding
and wintering habitats used throughout their annual cycle (Canadian Wildlife Service
and US Fish and Wildlife Service 2005). Collection of 1 egg from nests with 2 eggs in
WBNP occurred between 1967 and 1996 (see Kuyt 1993) to establish and bolster
captive breeding programs at various breeding facilities and to facilitate reintroduction
programs. The population (wild and captive) now has approximately 500 individuals,
with over 230 individuals in the wild migratory population (Stehn 2006). Captive
Whooping Cranes were raised in isolation from direct human contact (isolation-reared;
see Nagendran et al. 1996) and released into the Kissimmee Prairie region of Central
Florida, initiating a non-migratory population in 1993 (Nesbitt et al. 1997). This nonmigratory
population currently has approximately 44 individuals (Stehn 2006).
Prior to the establishment of a non-migratory population of Whooping Cranes,
the Florida Fish and Wildlife Conservation Commission (FFWCC) investigated
whether individuals from a genetically migratory population could be used to establish
a non-migratory population in Central Florida (Nesbitt and Carpenter 1993). By
placing eggs from a migratory population of Grus canadensis Linnaeus (Sandhill
Crane) into nests of a non-migratory Sandhill Crane population in Florida (crossfostered;
see Drewein and Bizeau 1978) and isolation-rearing migratory Sandhill
Crane chicks, the FFWCC showed that Sandhill Crane chicks from genetically
migratory populations did not move greater distances after fledging than did wild
non-migratory Sandhill Cranes under natural conditions (Nesbitt and Carpenter
1993). Nesbitt and Carpenter (1993), therefore, correctly predicted that Whooping
Cranes from a genetically migratory population would not migrate if introduced into
Florida without being taught migration. The converse is less clear, however: does
migration behavior in Whooping Cranes have any innate component?
This paper discusses behavior of a pair of non-migratory Whooping Cranes that
left Florida in the spring of 2000, spent the summer in eastern Michigan, and
returned to Florida in the fall. Though describing this behavior as “migration” is
debatable, examining the events in these movements provides insight into the
processes of crane migration.
552 Southeastern Naturalist Vol. 6, No. 3
Both male and female Whooping Cranes had transmitters with unique frequencies
attached to unique colored leg bands (Melvin et al. 1983, Nesbitt et al. 1997).
Two R2000 receivers (Advanced Telemetry Services, Inc., Isanti, MN) were used for
ground and aerial tracking. A 1987 Chevrolet series S-20 van was equipped with two
Yagi directional antennas attached to a crossbar on top of the van, and coaxial cables
from each antenna carried the signal to a null/peak box attached to the radio receiver.
An Omni antenna was also used to track signals from flying birds. A Cessna 182
fixed-wing airplane tracked birds and often maintained visual sightings of the birds.
Two Yagi “H” style antennae were attached to the wing struts with coaxial cables
connected to a left/right directional box on the receiver in the plane. A Garmin model
530 Global Positioning System (GPS) unit, with moving map display to collect GPS
waypoints each time the birds were observed, was used in the airplane.
Our tracking protocol followed other Whooping Crane migration studies that used
radio telemetry (Howe 1989; Kuyt 1987, 1992). Using the radio signals, the plane
followed the birds until a visual observation could be made. Each time the birds were
observed in flight, the location and the type of flight (flapping, gliding, or spiraling)
were recorded. Once the birds landed in a night roost, personnel in the airplane recorded
the roost location. If the night roost could not be observed from the air, personnel in the
van utilized triangulation (Mech 1983) to determine the birds’ location.
Both Whooping Cranes were isolation-reared at the USGS Patuxent Wildlife
Research Center (Laurel, MD) and released on the Kissimmee Prairie, Fl when they
were 6–8 months old (the female in 1996, the male in 1997). These birds paired in
Lake County, Fl in the spring of 1999 and then established a home range near
Inverness (Citrus County), FL. The FFWCC recaptured both birds (the female on 7
July 1999, the male on 10 November 1999) to attach new radio transmitters, and the
birds were seen regularly throughout the winter and early spring of 2000. The last
date the birds were seen or radio signals heard in Florida was 6 April 2000, and they
were next seen in Sandoval, IL (38°37.0'N, 89°6.8'W, Fig. 1). There the birds were
observed foraging (and probably roosting) in flooded cornfields from 11–15 May
2000. Though it could have been caused by extensive drought in the breeding area, it
is unclear why the birds left Florida in the first place.
On 15 May 2000, this pair of Whooping Cranes was also observed foraging in
corn and alfalfa fields near Sandusky, MI. From this date, the pair roosted nightly in
flooded areas of cornfields through mid-June, after which they moved to peat bogs
owned by the Michigan Peat Company. Here, company personnel observed the birds
daily for the next six weeks. Within the bog, the pair danced and vocalized together,
aggressively defending their territory from local Sandhill Crane pairs. No one observed
the pair flying during this 6-week time period, so it is possible one or both
members of the pair molted, but this could not be confirmed. This pair was observed
flying again 15 July, when they reappeared in local agriculture fields. From mid-July
until November, the Whooping Cranes foraged daily in agricultural fields and
roosted nightly in the reclaimed peat bogs. A tracking team from the International
Crane Foundation arrived on 6 November to observe the birds daily. A flock of 6
Sandhill Cranes was observed with the Whooping Cranes regularly, but the Whooping
Cranes moved and roosted independently of this flock.
On 21 November, this pair of Whooping Cranes left Sandusky, MI at 0700h (a
few minutes after sunrise; Table 1) and flew south (Fig. 1) as a snow storm with NW
winds developed. On this day, hundreds of local migratory Sandhill Cranes, as well
as this Whooping Crane pair, departed the Midwest and headed south. The pair was
not seen the first day due to snowstorms; but the airplane tracked these birds to the
north shore of Lake Erie, near Point Pelee National Park, ON, Canada by late
2007 Notes 553
afternoon. The birds were still flying when the airplane was grounded by continuing
bad weather and nightfall. The ground crew in the van did not hear radio signals at
Point Pelee that first night or the next morning, so the birds likely crossed the lake
after dusk and roosted on the south shore of Lake Erie, between Cleveland and
Sandusky, OH (Fig. 1).
On the morning of 22 November, the female was first detected flying south of
Cleveland, OH around 1000. Based on the location of the female’s signal and our search
pattern earlier in the morning, we estimated her departure from night roost to have been
Figure 1. Spring location of the Whooping Crane pair and the fall migration route of the
Whooping Crane female. Numbers correspond to roost locations in Table 1.
554 Southeastern Naturalist Vol. 6, No. 3
0930h (Table 1). Once the aerial trackers established visual contact, only the female was
seen; the male’s radio signal had not been heard since the previous afternoon. The
airplane continued following the female while the ground crew searched for the male
along the south shore of Lake Erie without success. On 23 November, the female left her
night roost in southern Ohio (Table 1) and continued due south by southeast. She was
observed spiraling up and gliding in flight, a conventional crane migratory behavior. On
24 November, as the elevation of the Appalachian Mountains increased near the
Tennessee/North Carolina border, the female’s flight behavior changed from spiraling
and gliding to extensive wing flapping while her path altered from south by southeast to
southwest, paralleling the mountains (points 4 and 5, Fig. 1). She landed in a pasture
with a pond at midday and remained here on 25 and 26 November (Table 1). Though
cornfields were located adjacent to her night roosts on 25 and 26 November, she fed in
alfalfa fields and the pasture on both days. On no other day was the female observed
feeding for more than 30 minutes.
The female Whooping Crane crossed the mountains on 27 November and returned
to her original bearing (Fig. 1). Upon crossing the mountains, the female also returned to
her previous flight behavior of spiraling and gliding. This behavior continued on 28
November. On 29 November, the female had returned to the original line that she was
flying along before reaching the Appalachian Mountains. The line was a straight
trajectory between the departure point and the area where she was released as a subadult
(Fig. 1). This trajectory was held briefly on 29 November, but then altered substantially
when she passed over the Okefenokee Swamp in southern Georgia (Fig. 1). Over the
Okefenokee, the female’s trajectory altered from south by southeast to southwest and
she flew directly towards Inverness, FL, the original home range of this pair in 1999 and
early 2000. After roosting one night at Inverness, the female departed on 01 December
and was tracked by the FFWCC to Kissimmee Prairie (her original release area) in
Table 1. Flight statistics for the female Whooping Crane during the return flight to Florida.
Latitude, Departure Flight Distance Flight rate
Date LocationA longitude time hours km (mi.) kph (mph)
11/21/00 Sandusky, MI (1) 43°23.7'N, 0700 11.0 300.8 (188.0) 27.4 (17.1)
11/22/00 South Shore Lake 41°26.9'N, 0930B 7.5 355.2 (222.0) 47.4 (29.6)
Erie, OH (2) 82°42.5'W
11/23/00 Langsville, OH (3) 39°5.1'N, 1021 6.2 307.2 (192.0) 50.0 (31.2)
11/24/00 Lebanon, VA (4) 36°53.2'N, 1030 2.5 195.2 (122.0) 78.1 (48.8)
11/25– Chuckey, TN (5) 36°11.0'N, 0955 7.3 224.0 (140.0) 30.6 (19.1)
11/27/00 Anderson, SC (6) 34°32.9'N, 0930 7.3 297.6 (186.0) 41.1 (25.7)
11/28/00 Statesboro, GA (7) 32°25.3'N, 1005 7.9 331.2 (207.0) 41.8 (26.1)
11/29/00 Starke, Fl (8) 29°54.7'N, 0910 3.8 136.0 (85.0) 35.5 (22.2)
11/30/00 Inverness, Fl (9) 28°51.2'N, 1030 6.0 171.2 (107.0) 28.5 (17.8)
12/01/00 Kissimmee Prairie, 27°53.7'N, - - - -
Fl (10) 81°10.0'W
ANumbers in parentheses correspond to roost locations in Figure 1.
BEstimated departure time due to inability to find the previous night’s roost.
2007 Notes 555
Central Florida. She was observed later that day in a flock of 12 Whooping Cranes on the
edge of Lake Kissimmee, Osceola County, Fl (M. Folk, Florida Fish and Wildlife
Conservation Commission, Tallahassee, FL, pers. comm.). Though observations have
continued to the time this paper was written, the female has not repeated this extensive
movement nor has the male been seen again; he is presumed dead.
Thus, after being paired for one year in Florida, this pair of Whooping Cranes
flew from Florida to Michigan, via Illinois, in as many as 30 days during spring. In
fall, however, the female of this pair flew from Michigan to Florida in only 11 days
(Table 1) and along a relatively straight line (Fig. 1). The total ground distance
traveled was 2318 km (1449 mi.) in 59.5 hours of flying. She flew an average of
257.6 km (161.0 mi), for an average of 6.6 flight hours per day. Her average ground
speed was 39.0 kph (26.4 mph).
The female’s flight behavior, including flight rate (kph/mph) and average distance
per day, was similar to other studies tracking migrating cranes (Anderson et al.
1980; Crete and Toepfer 1978; Kuyt 1987, 1992; Melvin and Temple 1982). Her
flight behavior was also similar to normal crane migration behavior: rising on
thermals to gain altitude and then gliding between thermals wherever possible
(Melvin and Temple 1982). The only time she used extensive wing flapping was
during cloudy or windy weather (i.e., when thermals are normally absent) and when
she had difficulty crossing the Appalachian Mountains.
The female Whooping Crane made the 2300 km (1450 mi.) trip south in 11 days,
flying almost every day and with little foraging occurring in any one day. This suggests
that this pair of Whooping Cranes may have experienced hyperphagia prior to their
movement south, accumulating fat (Klasing 1998) and flight muscle (Krapu et al. 1985,
Lindstrom and Piersma 1993) by foraging mainly in harvested cornfields. There is
evidence to suggest this body conditioning occurs more readily in captive migratory
crane species compared to captive non-migratory cranes (Swengel 1992). Though a
change in photoperiod over the weeks leading up to the initiation of movement south
may have been an ultimate trigger for hyperphagia and eventual migration in these
Whooping Cranes (Gwinner 1996), the proximate influence of photoperiod on crane
migration is unknown. Outside of a staging period in northern Saskatchewan, migratory
Whooping Cranes from the ANWR/WBNP flock also move quickly to winter areas
during fall migration, making the 3000 km (1900 mi.) journey from Saskatchewan to
Texas in 7–10 days (Kuyt 1992). During this migration period, Whooping Cranes roost
in a wide variety of areas containing shallow, open water (Howe 1989), similar to what
this female used (Hayes et al. 2002). On stopover sites, little foraging by migrating
cranes was observed in either study (Howe 1989, Kuyt 1992). Pre-migratory body
conditioning by this population has also been observed prior to northern movement
during winter and early spring at ANWR (Chavez-Ramirez 1996).
What caused this female Whooping Crane to move south from Michigan? Poor
weather conditions may have been the proximate factor that helped the pair initiate
the movement south. If weather was the ultimate factor as well, however, the female
should have stopped anywhere along the migration route once winter weather was
avoided, a situation that occurred as early as roost 2 and 3 (Fig. 1).
We argue that the ultimate factor causing the female to return to Florida here is
akin to natal philopatry through migration and was stimulated by a change in
photoperiod. This appears to be a prevalent force in Whooping Cranes, driving them
to return to their hatch location annually (Goosen and Kuyt 1986). To accomplish
this, the female Whooping Crane likely used a combination of orientational (flying
on a direct bearing) and navigational (“steering”) migration to guide her flight
(Alerstam 1990). In the beginning of her flight, the female Whooping Crane flew
556 Southeastern Naturalist Vol. 6, No. 3
consistently south by southeast, on a direct bearing to her release site, even though
she likely did not use this bearing in the spring because she and her mate had stopped
in Illinois (Fig. 1), a location far west of the line flown in the fall. This suggests
orientational migration. After being involuntarily displaced by the mountains, the
female also flew parallel to the mountains before finding a path over them, suggesting
navigation. When she reached the Okefenokee Swamp, an area that may have
been familiar to her (her closest recorded location while residing in Florida was
within 200 km/125 mi.; see Hayes et al. 2002), she veered from her south by
southeast azimuth to a southwest trajectory, guiding her to her last known home
range; this also suggests the use of navigation. Rather than remaining at Inverness,
however, the female next returned to Kissimmee Prairie, her original release site that
she may have considered a natal area.
Ample evidence exists suggesting that migration in cranes has both innate and
learned components. Migratory Sandhill Crane chicks raised by non-migratory parents
did not disperse greater distances from natal areas than non-migratory Sandhill
Cranes do naturally (Nesbitt and Carpenter 1993). This study supports the theory that
migration is a learned behavior for cranes. Our data, however, suggest that though
much about migration may be learned, behavioral mechanisms (e.g., using spiraling/
gliding flight techniques and returning to a certain geographic location along an
unknown path) and physiological mechanisms (e.g., increasing fat and muscle stores
in preparation for a migratory movement) may be genetic and occur in response to
proper environmental cues such as day length. Though our sample size for most of
these data is one bird, they are still important as they reflect the physiological
capacity of a species to respond to an unusual situation. In addition, other similar
movements (see below) have been seen in a reintroduction project for migratory
Whooping Cranes between Wisconsin and Florida.
Management implications.The existence of an innate component to crane migration
is relevant to current and future crane reintroduction efforts. Without having
moved such a large distance prior to this event, this female was able to store
sufficient energy to successfully fly from Michigan to Florida in 11 days, only
stopping for 2 consecutive days during the migration. During these stops, highenergy
foods were not consumed, so we presume she had gathered sufficient fat
reserves for the entire migration. Furthermore, the female was able to return to her
original release area, without ever flying that route before, after responding to proper
weather cues that initiated migration. While not necessarily prevalent in other crane
species, migration may not be solely a learned behavior in Whooping Cranes. This
remarkable event suggests refinements are possible for techniques that teach naïve
cranes new migration routes where historic flyways have been lost.
Teaching birds to follow a human directed guide (ultra-light [Lishman et al.
1997], motorized ground vehicle [Ellis et al. 1997], or powered hang glider [C.
Mirande, International Crane Foundation, Baraboo, WI, pers. comm.]) is costly,
time-consuming, and requires significant training (human and crane). Though these
techniques may be wholly appropriate and necessary, other techniques can still be
tested on Whooping Cranes and applied to specific situations. Our data suggest that
Whooping Crane chicks raised, familiarized, and fledged on breeding grounds could
be shipped (either whole or in part) to a winter area and then migrate back on their
own, as long as significant barriers (e.g., deserts, large water bodies, or tall mountains)
do not cross the pathway the birds would fly. Birds could also be led on
migration for part of the journey and then be crated and shipped. This would be
important where political boundaries cannot be crossed (e.g., Siberian Cranes crossing
several countries lying between Russia and India; C. Mirande, pers. comm.).
2007 Notes 557
With Whooping Cranes, an important conservation goal is to establish a migratory
population separate from the ANWR/WBNP population. Currently in Wisconsin, two
techniques are employed: birds raised to follow an ultra-light aircraft and those directly
released with wild Sandhill Cranes and introduced Whooping Cranes. This reintroduction
effort presents the opportunity to investigate these hypotheses on a larger scale. So
far, several Whooping Cranes have displayed irregular paths while migrating, and these
examples can clarify our understanding of the migration ecology for this species.
Acknowledgments. We thank the Florida Fish and Wildlife Conservation Commission
for historical information about this pair of Whooping Cranes, for up-to-date
information on the Florida Whooping Crane reintroduction program, and for maintaining
radios in this flock so diligently. Mark and Marilyn Batkie provided lodging
and summer observations for staff, while the Michigan Peat Company provided
access to their land and summer observations as well. We thank the Windway
Corporation for donated flight time, and Mike Frakes (our pilot) for keeping us safe
over many hours in the air. We thank the landowners, who provided access to their
land along the migration path. Dorn Moore and Tamara Miller provided mapping
assistance, and Zoe Rickenbach constructed the final map. Betsy Didrickson assisted
with library searches. Finally, Steve Nesbitt, Oliver Pattee, Mike Putnam, Gary
Richardson, Kelley Tucker, and two anonymous reviewers provided useful comments
on this manuscript, while Scott Swengel provided assistance on an earlier
version of this manuscript.
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1International Crane Foundation, E-11376 Shady Lane Road, Baraboo, WI 53913. 2PO Box
1998, Lihue, HI 96766. 34-4-16 Naruiwa, Cheltonomori, Toyohira, Chino, Nagano, Japan.
*Corresponding author - firstname.lastname@example.org.