2006 Notes of the SouNtOhReTaHsEtAeSrTEnR NN NaAtTuUrRaAlLiIsStT, Issue 6/3, 20103(71):39–42 551 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) 82°37.2'W 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) 82°15.2'W 11/24/00 Lebanon, VA (4) 36°53.2'N, 1030 2.5 195.2 (122.0) 78.1 (48.8) 82°01.7'W 11/25– Chuckey, TN (5) 36°11.0'N, 0955 7.3 224.0 (140.0) 30.6 (19.1) 26/00 82°41.3'W 11/27/00 Anderson, SC (6) 34°32.9'N, 0930 7.3 297.6 (186.0) 41.1 (25.7) 82°31.2'W 11/28/00 Statesboro, GA (7) 32°25.3'N, 1005 7.9 331.2 (207.0) 41.8 (26.1) 81°40.5'W 11/29/00 Starke, Fl (8) 29°54.7'N, 0910 3.8 136.0 (85.0) 35.5 (22.2) 82°3.46'W 11/30/00 Inverness, Fl (9) 28°51.2'N, 1030 6.0 171.2 (107.0) 28.5 (17.8) 82°16.7'W 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. Literature Cited Alerstam, T. 1990. Bird Migration. Cambridge University Press, New York, NY. 428 pp. Anderson, R.K., D.K. Jansen, and T. Cogger. 1980. Fall and spring migration route and behavior of Eastern Greater Sandhill Cranes 1978–1979. US Fish and Wildlife Service, Minneapolis, MN. Allen, R.P. 1952. The Whooping Crane. National Audubon Society Research Report No. 3. National Audubon Society, New York, NY. 246 pp. Allen, R. P. 1956. A report on the Whooping Crane’s northern breeding grounds. Supplement to Research Report No. 3. National Audubon Society, New York, NY. 60 pp. Canadian Wildlife Service and US Fish and Wildlife Service. 2005. Draft International Recovery Plan for the Whooping Crane. Recovery of Nationally Endangered Wildlife (RENEW), Ottawa, ON and US Fish and Wildlife Service, Albuquerque, NM. Chavez-Ramirez, F. 1996. Food availability, foraging ecology, and energetics of Whooping Cranes Wintering in Texas. Ph.D. Dissertation. Texas A&M University Press, College Station, TX. Crete, R.A., and J.E. Toepfer. 1978. Migration of radio-tagged Eastern Greater Sandhill Cranes. Mimeo Report. US Fish and Wildlife Service, Minneapolis, MN. Drewein, R.C., and E.C. Bizeau. 1978. Cross-fostering Whooping Cranes to Sandhill Crane foster parents. Pp. 201–202, In S.A. Temple (Ed.). Endangered Birds: Management Techniques for Preserving Threatened Species. University of Wisconsin Press, Madison, WI. 308 pp. Ellis, D.H., B. Clauss, T. Watanabe, R.C. Mykut, M. Kinlock, and C.H. Ellis. 1997. Results of an experiment to lead cranes on migration behind motorized ground vehicles. Pp. 114–122, In R.P. Urbanek and D.W. Stahlecker (Eds.). Proceedings Seventh North American Crane Workshop. North American Crane Working Group, Grand Island, NE. 262 pp. Goosen, J.P., and E. Kuyt. 1986. Natal and breeding dispersal of Whooping Cranes (Grus americana) [abstract]. XIX Congressus Internationalis Ornithologicus. Abstracts 646. Gwinner, E. 1996. Circadian and circannual programmes in avian migration. Journal of Experimental Biology 199:39–48. Hayes, M.A., A.E. Lacy, J.A. Barzen, K.A.L. Hall, K. Suzuki, S.E. Zimorski. 2002. The unusual journey of a pair of non-migratory Whooping Cranes (Grus americana). [Unpublished Report] Located at: Ron Sauey Memorial Library, International Crane Foundation, Baraboo, WI. 558 Southeastern Naturalist Vol. 6, No. 3 Howe, M.A. 1989. Migration of radio-marked Whooping Cranes from the Aransas-Wood Buffalo population: Patterns of habitat use, behavior, and survival. US Fish and Wildlife Technical Report 21. US Fish and Wildlife Service, Washington, DC. Klasing, K.C. 1998. Comparative Avian Nutrition. CAB International, New York, NY. 360 pp. Krapu, G.L., G.C. Iverson, K.J. Reinecke, and C.M. Boise. 1985. Fat deposition and usage by arctic-nesting Sandhill Cranes during spring. Auk 102:362–368. Kuyt, E. 1987. Whooping Crane migration studies 1981–82. Pp. 371–379, In G.W. Archibald and R.F. Pasquier (Eds.). Proceedings of 1983 International Crane Workshop. International Crane Foundation, Baraboo, WI. 596 pp. Kuyt, E. 1992. Aerial radio-tracking of Whooping Cranes migrating between Wood Buffalo National Park and Aransas National Wildlife Refuge, 1981–84. Canadian Wildlife Service Occasional Paper. Canada Wildlife Service, Ottawa, ON, Canada. Kuyt, E. 1993. Whooping Crane, Grus americana, home-range and breeding-range expansion in Wood Buffalo National Park, 1970–1991. Canadian Field-Naturalist 107:1–12. Lindstrom, A., and T. Piersma. 1993. Mass changes in migrating birds: The evidence for fat and protein storage re-examined. Ibis 135:70–78. Lishman, W.A., T. Teets, J.W. Duff, W.J.L. Sladen, G.G. Shire, K.M. Goolsby, K.W.A. Bezner, and R.P. Urbanek. 1997. A re-introduction technique for migratory birds: Leading Canada Geese and isolation-reared Sandhill Cranes with ultralight aircraft. Pp. 371–379, In R.P. Urbanek and D.W. Stahlecker (Eds.). Proceedings Seventh North American Crane Workshop. North American Crane Working Group, Grand Island, NE. 262 pp. Mech, D.L. 1983. Handbook of animal radio-tracking. University of Minnesota Press, Minneapolis. MN. 120pp. Melvin, S.M., and S.A. Temple. 1982. Migration ecology of Sandhill Cranes: a review. Pp. 73– 87, In J.C. Lewis (Ed.). Proceedings 1981 Crane Workshop. National Audubon Society, Tavernier, FL. 296 pp. Melvin, S.M., R.C. Drewien, S.A. Temple, and E.G. Bizeau. 1983. Leg-band attachment of radio transmitters for large birds. Wildlife Society Bulletin 11:282–285. Nagendran, M., R.P. Urbanek, and D.H. Ellis. 1996. Special Techniques, Part D: Reintroduction Techniques. Pp. 231–240, In D.H. Ellis, G.F. Gee, and C.M. Mirande (Eds.). Cranes: Their Biology, Husbandry, and Conservation. Department of the Interior, National Biological Service, Washington, DC, and International Crane Foundation, Baraboo, WI. 308 pp. Nesbitt, S.A., and J.W. Carpenter. 1993. Survival and movements of greater Sandhill Cranes experimentally released in Florida. Journal of Wildlife Management 57:673–679. Nesbitt, S.A., M.J. Folk, M.G. Spalding, J.A. Schmidt, S.T. Schwikert, J.M. Nicolich, M. Wellington, J.C. Lewis, and T.H. Logan. 1997. An experimental release of Whooping Cranes in Florida : The first three years. Pp. 79–85, In R.P. Urbanek and D.W. Stahlecker (Eds.). Proceedings Seventh North American Crane Workshop. North American Crane Working Group, Grand Island, NE. 262 pp. Nesbitt, S.A., M.J. Folk, K.A. Sullivan, S.T. Schwikert, and M.G. Spalding. 2001. An update of the Florida Whooping Crane release project through June 2000. Pp. 62–72, In D.H. Ellis (Ed.). Proceedings of the Eighth North American Crane Workshop. North American Crane Working Group, Seattle, WA. 226 pp. Stehn, T. 2006. Whooping Crane Recovery Activities: April–September 2006. North American Crane Working Group, Seattle, WA. Swengel, S. 1992. Sexual size dimorphism and size indices of six species of captive cranes at the International Crane Foundation. Pp. 151–158, In D.W. Stahlecker (Ed.). Proceedings Sixth North American Crane Workshop. North American Crane Working Group, Grand Island, NE. 179 pp. 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 - matt@savingcranes.org.