Tom Stehn is now the “Whooping Crane Science Advisor” for Friends of the Wild Whoopers (FOTWW). Tom will provide answers to questions about Whooping Cranes posed by the interested public. Tom will also provide guidance to FOTWW concerning conservation, management and future needs of the Aransas-Wood Buffalo population of wild Whooping Cranes. The Aransas-Wood Buffalo Whooping Crane flock is the only self-sustaining wild population on earth.
A question and answer section “Ask Tom Stehn” has been established on FOTWW’s web page. Questions asked by anyone will be entertained on the web site in an effort to provide scientifically accurate information to the public. To go to the site click here.
Tom Stehn’s professional qualifications and experience with Whooping Cranes are well known in the scientific community. He is a world class Whooping Crane biologist. He retired from the U.S. Fish and Wildlife Service in 2011.
Tom served as the refuge biologist at the Aransas National Wildlife Refuge for 15 years and as the U.S. Coordinator of Whooping Crane Recovery Program for 14 years. During these years he kept tabs on the only wild population of Whooping Cranes on earth, serving as the observer on weekly census flights.
He served as a member of the Whooping Crane Recovery Team for 25 years. He directed management and research efforts on the Whoopers, publishing 17 scientific articles. Twice he helped radio-track the cranes between Texas and Canada, helped get erosion control mats installed along the Gulf Intracoastal Waterway, and served for many years as the burn boss at Aransas carrying out prescribed burns to promote upland whooping crane use.
In 2016, Tom was selected by the North American Crane Working Group as the 8th recipient of the Walkinshaw Award given for long-time contributions to crane research and conservation. He has received may other awards during his distinguished career.
Tom Stehn has always stood ready to help others who needed to tap into his knowledge base and sought his advice. Friends of the Wild Whoopers is pleased and honored that he is continuing his willingness to share his knowledge about Whooping Cranes.
Wade Harrell, U.S. Whooping Crane Recovery Coordinator
Wintering Whooping Crane Update
Fall migration is coming to a close and whooping cranes have all moved south out of their breeding grounds in Wood Buffalo National Park (WBNP). It was a record breeding year in WBNP; with above average conditions contributing to an estimated 63 fledged whooping cranes headed South on their first migration to Texas. The Whooping Crane migration from Wood Buffalo to Aransas is about 2,500 miles in length and can take up to about 50 days to complete. It will probably be a few more weeks until the entire Aransas Wood Buffalo whooping crane population has arrived on the Texas coast. We were able to fit a few whooping crane juveniles this August in WBNP with new cellular-based telemetry equipment, and I want to walk you through the fall migration of one of these juveniles and its parents.
First off, let me provide a bit of information about our new telemetry devices. In our former telemetry study, we used satellite-based telemetry. These devices provided 3-5 locations every 24 hours and communicated that via space satellite. Our new telemetry devices have the capability to provide significantly more data compared to our previously used devices. We are now using cellular-based telemetry devices, meaning they relay location data using ground-based cellular towers, just like your mobile phone does. The device is powered by a solar-charged battery. As long as the marked bird is in the range of a cellular tower, we receive a data download every day via internet. Each data download contains locations for the bird every 30 minutes over the past 24 hours. The new telemetry devices are also equipped with what is called an accelerometer, meaning we can determine the speed of the bird, indicating if it is in flight or on the ground.
The journey of “7A”, fall 2017 migration:
On 2 August, a team of biologist captured and marked a 3 month old whooping crane in Wood Buffalo National Park, around the nest where he was hatched about 60 miles south of the Great Slave Lake, and fitted him with one of our new cellular-based telemetry units (identified as “7A”). This young whooping crane and his parents left their breeding area the morning of 26 September, to start on their long journey south.
On the first night away from their nesting area, 7A and his family roosted on Gipsy Lake, 35 miles SE of Fort McMurray, AB. The next morning (27 September) the family traveled to Witchekan Lake near Spiritwood, SK and spent the night. On the morning of 28 September, they traveled to their “staging ground” area, the prairie pothole region of Central Saskatchewan. They spent the next month foraging on waste grains in the agricultural areas and in wetlands around Prud’ Homme, SK. After a strong frontal passage bringing northerly winds and colder weather, they proceeded south on the morning of 29 October.
They crossed the Canada/United States border around mid-day near the NW corner of North Dakota and spent that night on the banks of the Missouri River about 20 miles SE of Bismarck, North Dakota. The next morning, 30 October, they continued south, roughly following the Missouri River as it winds through South Dakota. With a strong tailwind, they were able to cross South Dakota in about 3 hours, without stopping. They continued through Nebraska that day, crossing the Platte River just east of Gibbon, Nebraska. They did not stop in Nebraska either, traversing the state in about 4 hours. That evening they arrived at Cheyenne Bottoms Wildlife Area in Central Kansas, known as the largest interior wetland in the United States. This is a well-known and established migration stopover habitat location for not only whooping cranes, but a number of other migratory bird species. The next afternoon, on 31 October, they traveled about 20 miles south to Quivira National Wildlife Refuge, where they would spend the next 12 days. Quivira NWR received a record amount of migrating whooping crane use this fall, with over 112 individuals reported there, more than 25% of the Aransas-Wood Buffalo population.
They left Quivira NWR on the morning of 12 November and traveled south about 150 miles to an area of native mixed-grass prairie about 3 miles west of Fairview, Oklahoma. They spent 3 days there, leaving on the morning of 15 November and crossing the Texas border mid-day just to the east of Wichita Falls. That night, they roosted on a farm pond in Bosque County in central Texas. The morning of 16 November, the family continued south through Texas, stopping briefly in southern Bastrop County and then northern Gonzales County. Evidently they were disturbed that night as they made several, short nighttime movements just west of Waelder, Texas. Nocturnal flight is fairly rare and relatively unknown for whooping cranes, but our new telemetry devices allows us to observe this behavior. Only a short distance from their winter home, they left the morning of 17 November and headed south. Early that afternoon, they flew over Victoria, just north of Aransas NWR. Shortly thereafter, they made it to the Tatton Unit of Aransas NWR and roosted there along Salt Creek. The next morning, they made a short jump south and set up what looks to be their wintering territory here on Aransas NWR, where they will likely spend most of their time over the next several months.
The “7A” family had a fairly normal fall migration, taking 52 days and a bit over 2,500 miles to complete. You’ll note that the “pit stops” that they made along the way almost always were tied to quality wetland and prairie habitats. Protecting and restoring these types of habitats across the vast Great Plains of North America really is key to making sure whooping crane migrations are successful.
Texas Whooper Watch
Be sure to report any Texas migration sightings via email: email@example.com or phone: (512) 389-TXWWW (8999)
Current conditions at Aransas NWR:
Food & Water Abundance:
You’ve likely seen many of the news articles related to the impacts of Hurricane Harvey on Aransas NWR, so I won’t go into detail here on that topic. But from all appearances, the coastal marsh habitat that whooping cranes rely on here in the winter seem to have held up well to what is a natural disturbance. While the human impact has been significant, natural habitats often quickly recover after this type of event. From a long-term perspective, the freshwater inflows associated with the hurricane’s rain event will improve coastal marsh condition. We’ve seen a number of whooping cranes that have arrived at Aransas NWR foraging successfully in the coastal marsh as they have for eons. We will continue to monitor habitat conditions and whooping crane behavior and adjust our management accordingly.
Long-time volunteers recognized:
I want to take a minute to recognize a few long-time volunteers at Aransas National Wildlife Refuge that really do make a difference for our wildlife and wild places. First off, Ron Smudy, a long-time volunteer at Aransas, will be awarded as the 2017 Coastal Steward by the Coastal Bend Bays Foundation at the annual Environmental Awards banquet on 7 December. Ron has put a great deal of “sweat equity” into Aransas over the years, from mowing, cutting and spraying invasive species to helping our maintenance staff with all sorts of projects. We truly wouldn’t have the Refuge as we know it without folks like Ron. Additionally, I want to recognize Fred and Linda Lanoue, long-time board members of the Friends of Aransas and Matagorda Island Refuge. They will soon be leaving Texas and were honored this past Saturday at a luncheon, thanking them for all their work with environmental causes around the Texas coastal bend. Fred and Linda’s tireless work with the FAMI board help us accomplish worthwhile projects that just wouldn’t be possible otherwise. Unfortunately, both Ron and the Lanoue’s were personally impacted by Hurricane Harvey. Our hearts go out to them as they start new chapters in their lives and we reflect on all the good work they have done at Aransas NWR.
The Unison Call, – Newsletter of the North American Crane Working Group –
Vol. 27 No. 2, The Fall/Winter 2016-1
457 Whooping Crane Eggs Taken from Canada’s Nesting Grounds – Enough is Enough!
By Chester McConnell, Friends of the Wild Whoopers
An astonishing 457 whooping crane eggs were removed from nesting grounds in Canada’s Wood Buffalo National Park (WBNP) from 1964 to 1998 to be used in several experimental population projects and to establish (or augment) captive breeding programs. The eggs were taken from the only self-sustaining wild population of whooping cranes in the world, which is known as the Aransas-Wood Buffalo population (AWBP). The significance of such management decisions cannot be overemphasized. As of 2016, the AWBP numbers an estimated 329 birds. We can only imagine how much larger the AWBP would be today if the 457 eggs had not been removed. Certainly, not all of the eggs would have produced birds that would have survived and added to the population, but some would have.
Importantly, we need to recall why the eggs were removed. There was concern during the 1940s (and subsequently) that the AWBP could become extinct. Only 18 whooping cranes remained in that population in 1944-45. By 1967 there were just 9 nesting pairs. The U.S. Fish and Service (USFWS) and Canadian Wildlife Service (CWS) decided to make an attempt to help the species.
The two agencies made well-intentioned efforts, based on information at the time, to safeguard the AWBP, by establishing and then increasing the numbers and genetic diversity in the captive flocks used to produce eggs and, starting in 1975, by trying to establish new wild populations in new locations. Some of the repopulation attempts were failures, while others are still ongoing (with outcomes still unknown). Even so, there have been, and continues to be, serious differences of opinions about the various efforts and especially those involving taking whooping crane eggs from nests in WBNP.
Removal plans for whooping crane eggs
The egg removal plan involved taking one egg from nests with two eggs. (Technical information in this article is summarized from the International Recovery Plan for the whooping crane 2007, Appendix C, Egg Collection, pages C1 through C5.) The decision to collect one of two eggs from wild nests was made in 1965. Research personnel had learned that, although whooping cranes normally lay two eggs, only about 15% of families arriving on the Aransas National Wildlife Refuge (ANWR) wintering area have two chicks. Therefore, about 85% of nests usually contain one egg that is unlikely to result in a fledged chick. However, the second egg plays an unknown role in providing insurance that at least one chick survives. Habitat conditions, including water levels, food availability and predator abundance, affect survival. In years with suitable habitat conditions, crane pairs may raise two young. For example, during the 1958-59 winter, 8 of the 9 young that arrived at Aransas were from twin pairs. In 1997 and 1998, at least 9% of second-hatched whooping crane young survived to fledging age.
During the 61-year period from 1938 to 1998, there were 34 years in which no egg collection occurred at WBNP (mostly pre-1967). In those 34 years, 16 pairs of ‘twin’ juveniles arrived at ANWR in the fall. During the 27 years of egg collection at the nesting grounds, no pairs of twin juveniles arrived at ANWR in the fall (Cannon et al., 2001).
Brief history of whooping crane eggs taken
Eggs were first taken from 1967 to 1971 and in 1974 to further augment the Patuxent Wildlife Research Center (PWRC) captive population. More eggs were taken from 1975 through 1988 to provide 215 eggs for the Grays Lake cross-fostering experiment. Egg transfers to PWRC were resumed in 1982-1989 and 1991-1996, with 178 eggs being transferred. Fifty-eight eggs were transferred to the International Crane Foundation (ICF) beginning in 1990 and resumed in 1992-1996. Six eggs were shipped to the Calgary Zoo in 1994 and 1998, and a chick was transferred there from WBNP in 1999. Two eggs from an abandoned nest were picked up opportunistically in May 1998 and transferred to Calgary Zoo. Between 1967 and 1998, 244 eggs were taken from WBNP to the captive sites.
Effects on population growth rate
The effects of egg collection on the growth rate and overall fitness of the wild AWBP are unknown. There was, and remains, much disagreement among whooping crane professionals. Some contend that egg removals have not adversely affected the productivity of the wild population (e.g. Ellis and Gee, 2001). They point out that between 1967 and 1996, the era of egg pickups, the AWBP increased from 48 to 160, and the number of nesting pairs increased from 5 to 45. After reviewing and critiquing the several research findings, James Lewis, USFWS (retired biologist), in 2001, concluded that the data as presented did not support the views of Cannon et al. (2001) and determined that a re-analysis of the existing egg collection data was warranted (Lewis, 2001).
CWS biologist Brian Johns (retired) reviewed the data pair by pair and extracted as much information as possible from original reports and solicited the expertise of Dr. Mark Boyce, University of Alberta, for the analysis (Boyce et al., 2005). However, it’s been suggested that the data set used has biases, including: non-random nest selection; lack of a control group; not testing eggs for viability in the early years of collection; limited samples in certain years; and potential inaccuracies in chick surveys. Because of these issues, it is not possible to say what impact egg pickup has had on the size of the AWBP.
Some reintroduction programs benefited
The Whooping Crane International Recovery Team (IRT) recognizes that collection of eggs has benefited the whooping crane recovery program by providing stock to establish the captive flocks and providing offspring for release, thus increasing the total number of whooping cranes (cranes artificially reared and released into the wild) and helping to preserve the genetics of the species. The IRT in 2007 believed that data analyses to date did not indicate that egg collection would increase recruitment in the AWBP over the long term, but could increase recruitment in selected years.
In 2016, the IRT initiated a process to update the International Recovery Plan for the Whooping Crane, 2007 (IRP-2007). The goal is to incorporate new information and techniques, with the overall goal of down-listing and eventually fully recovering the species. A whooping crane population viability analysis (PVA) process is being used to produce information to be included in an upcoming version of the IRP.
The PVA would include whooping crane egg harvest on WBNP as one of several management scenarios that would be considered. According to Wade Harrell (USFWS) (personal communication), “That does not necessarily mean that we will harvest eggs from nests, only that we are considering it as we model a number of different management scenarios. If the PVA models indicate that it would provide significant benefit to the population, we would consider it further as we look at political, logistical and cost constraints of various management scenarios. So, to be clear, no decisions have been made.”
Friends of the Wild Whoopers (FOTWW) is opposed to any additional collection of wild whooping crane eggs from WBNP. Based on several unpublished communications, we believe that poor parenting skills of captive-reared whooping cranes and/or habitat quality is the reason for the serious problems in the Eastern Migratory Population. According to the genetic master plan, the genetic diversity of the AWBP is well represented in the three captive flocks, hence there would be little to be gained genetically in the captive flocks by removing additional eggs from WBNP at this time. Genetic experts have recommended that, as a minimum before any additional eggs are picked up from the wild, a large-scale genetic study is needed in WBNP, since information on the composition of nesting pairs has been lost with the cessation of color-banding in 1988 (IRP 2007). Frozen semen banks should be maintained to prevent loss of founder lines. A national serum bank should be set up to serve as a repository of genetic material for the species.
FOTWW is not critical of experimental projects preformed in the past including the Gray’s Lake cross-fostering experiment and the augmentation of the PWRC whooping cranes. Such early projects were learning experiences and measures to help save the species. Yet it is inexcusable to waste more eggs taken from nest of the only remaining population of self-sustaining whooping cranes to repeat past failures.
FOTWW believes all eggs should remain in the nest on WBNP because there is no convincing need to take more.
Boyce, MS, SR Lele, BW Johns (2005) Whooping crane recruitment enhanced by egg removal. Biological Conservation 126:395-401.
Canadian Wildlife Service and U.S. Fish and Wildlife Service. 2007. International recovery plan for the whooping crane. Ottawa: Recovery of Nationally Endangered Wildlife (RENEW), and U.S. Fish and Wildlife Service, Albuquerque, New Mexico. 162 pp. (pages 51-52)
Cannon, JR, BW Johns, TV Stehn (2001) Egg collection and recruitment of young of the year in the Aransas/Wood Buffalo population of whooping cranes. Proceedings North American Crane Workshop 8:11-16.
Ellis, DH, GF Gee (2001) Whooping crane egg management: options and consequences. Proceedings North American Crane Workshop 8:17-23.
Lewis, JC (2001) Increased egg conservation: is it essential for recovery of whooping cranes in the Aransas/Wood Buffalo population? Proceedings North American Crane Workshop 8:1-5
Chester McConnell, President of FOTWW wrote the above article. He has worked for whooping cranes for 20 years in several capacities. Most recently as FOTWW’s President he has visited military bases and Indian Reservations throughout the whooping crane migration corridor in 7 states. He advises the military and Reservation personnel about how to develop and manage “stopover habitat” for the cranes. He also writes detailed management plans for all sites he visits. He is now being recruited to provide the same services for other areas along the migration corridor. McConnell and Pam Bates are the co-founders of Friends of the Wild Whoopers. McConnell also served with Whooping Crane Conservation Association for 12 years. He served as WCCA’s President, Board member, webpage manager and editor of their news letter. McConnell also served as a wildlife biologist with Tennessee Wildlife Agency and as Wildlife Management Institute Representative for 31 years where he was involved with a variety of wildlife species and their habitats. He has a Masters of Science in Wildlife Biology.
Wondering what is involved with counting whooping cranes?
Each fall, the natural wild flock of whooping cranes migrates the 2,500 miles from their nesting grounds at Wood Buffalo National Park in Alberta, Canada to Aransas National Wildlife Refuge for the winter. They live on the Texas coast a few months of the year and they spend that time feeding in the remote wetlands of the refuge and surrounding area. So how do U.S. Fish and Wildlife Service biologists estimate the number of whooping cranes in existence today? The answer: long hours in a small plane flying a grid and looking very, very closely at what is happening on the ground.
While the whooping cranes are in Texas, researchers conduct surveys by plane to gauge the status of the population. They fly several flights and while flying a grid pattern over the refuge, they have to be able to discern which birds are whooping cranes. Can you find the whooping cranes in the photo below?
The data collected from the flights is used to calculate an estimate of the wild whooping crane population. If you would like to see more photos and read more details about how USFWS conducts their aerial surveys on the Aransas NWR, click here.
Counting whooping cranes is not an easy task and FOTWW thanks the USFWS for taking the time and going into detail on how the surveys are conducted.
***** FOTWW’s mission is to help preserve and protect the Aransas/Wood Buffalo
population of wild whooping cranes and their habitat. *****
Friends of the Wild Whoopers is a nonprofit 501(c)3 organization.