David L. Trauger

Influence of age and selected environmental factors on reproductive performance of canvasbacks

Age, productivity, and other factors affecting breeding performance of canvasbacks (Aythya valisineria) are poorly understood. Consequently, we tested whether reproductive performance of female canvasbacks varied with age and selected environmental factors in southwestern Manitoba from 1974 to 1980. Neither clutch size, nest parasitism, nest success, nor the number of ducklings/brood varied with age. Return rates, nest initiation dates, renesting, and hen success were age-related. Return rates averaged 21% for second-year (SY) and 69% for after-second-year (ASY) females (58% for third-year and 79% for after-third-year females)

Migration and winter distributions of canvasbacks staging on the Upper Mississippi River

Fall and winter distribution patterns of canvasbacks (Aythya valisineria) staging on the upper Mississippi River near LaCrosse, Wisconsin (navigational Pools 7 and 8) and Keokuk, Iowa (Pool 19) were studied during 1973-77. Sightings and recoveries obtained from 1,488 color-marked males during 1973-75 and 3,789 banded males and females during 1973-77 suggested 2 principal migration corridors: 1 extending eastward from Pools 7 and 8 to the eastern Great Lakes and southeast to the Mid-Atlantic Region and another southward from Pools 7 and 8 to the lower Mississippi Valley, Gulf Coast, and east Texas regions. These discrete populations stage concurrently on Pools 7 and 8 during the fall, but winter in different areas of the Atlantic, Mississippi, and Central flyways. Populations staging on Pool 19 were not discrete from those staging on Pools 7 and 8. A continual turnover of birds passing through these staging areas was indicated. Canvasbacks wintering in the Mississippi and Central flyways were widely dispersed among a variety of habitats, whereas canvasbacks wintering in the Atlantic Flyway were concentrated in a few traditional habitats. Canvasbacks exhibited strong fidelity to wintering areas. Distribution patterns and population attributes of canvasbacks during fall and winter may be explained by the predictability of natural foods and their ability to exploit these foods. J. WILDL. MANAGE. 47(3):741-753 Principal migration corridors of canvasbacks have been described by Stewart et al. (1958), Geis (1959), and Bellrose (1968). The eastern continental population of canvasbacks was reported staging during fall on Lake Christina and Heron Lake in Minnesota (Smith 1946); Lakes Poygan, Koshkonong, Butte des Morts, Winnebago, and Winneconne in Wisconsin (Jahn and Hunt 1964); the Detroit River, Lake St. Clair, and Saginaw Bay in Michigan (Martz et al. 1976); and the Illinois River in Illinois (Mills et al. 1966). Canvasback use of these traditional staging areas declined dramatically from 1955 to 1966, during which time use of the upper Mississippi River, particularly navigational Pools 7, 8, and 19, increased (Mills et al. 1966; J. H. Stoudt, unpubl. rep., North. Prairie Wildl. Res. Cent., Jamestown, N.D., 1970; W. E. Green, unpubl. rep., Upper Miss. Fish and Wildl. Refuge, Winona, Minn., 1974). The effects of siltation, pollution, eutrophication, and rough fish on such preferred foods as fennelleaf pondweed (Potamogeton pectinatus), American wildcelery (Vallisneria americana), and fingernail clams (Sphaeriidae) have been cited (Mills et al. 1966, Trauger and Serie 1974) as causal factors responsible for the disappearance of canvasbacks from formerly important staging

Age-class determination of canvasbacks

A technique was developed to distinguish yearling from adult canvasbacks (Aythya valisineria) in the field during spring on the basis of white flecking on the distal ends of selected wing feathers. Covert feathers from adults had well-defined vermiculation patterns whereas feathers from yearlings lacked such markings. These age-related characters were confirmed by paired comparisons of feathers from the same captive birds in consecutive years and by discriminant analysis of feathers using densitometric measurements from known-age wild birds. Reflective densitometric measurements of greater secondary coverts for females and males were significantly different between 1and 2-year-old and between 2and 3-yearold canvasbacks. Greater secondary coverts were the best feathers for recognizing age-classes of males and females. Densitometric values indicate low variability among different observers and within samples. J. WILDL. MANAGE. 46(4):894-904 The ability to recognize age-classes within a population is important in understanding aspects of reproductive biology and population dynamics (Trauger 1971, Johnson 1978, Krapu and Doty 1979, Raveling 1981). Due to the low population status of the canvasback in recent years, the influence of breeding age on individual productivity has been of concern (Olson 1964, Trauger 1974b, Bellrose 1976). A reliable technique for distinguishing between age-classes of canvasbacks in spring was needed to identify the influence of age on reproductive success of yearlings and older, experienced birds. Techniques for separating age-classes, recently developed for other species of waterfowl, use several variables which complicate their application and reliability (Dane 1968, Dane and Johnson 1975, Blohm 1977, Krapu et al. 1979, Wishart 1981). Based on feather dimensions or distinctive markings, these techniques use key wing feathers or a combination of feathers to establish criteria for separating age-classes. White flecking or vermiculation patterns on the wing coverts of canvasbacks were recognized by Carney (1964) as a valuable criterion for separation of ageclasses. He developed a technique, primarily for use during the fall, which depended largely upon shape, wear, and degree of white flecking on the tertial feathers. This technique is less effective during the breeding season because of feather wear and replacement. The objectives of our study were to (1) identify wing feathers which reliably distinguish yearlings from older canvasbacks in the field at any time of year, and (2) develop a technique for quantitatively measuring these age-related characters. We acknowledge the Data Production Division of the EROS Data Center, U.S. Geological Survey, Sioux Falls, S.D., and in particular J. McCord and C. Lawson for assistance in development of densitometry for feather age classification techniques; E. L. Ferguson for encouragement; M. I. Meyer for preparing drawings of feathers; F. B. Lee for supervising the rearing of known-age canvasbacks; D. H. Johnson for assistance 1 Present address: Division of Wildlife Ecology Research, U.S. Fish and Wildlife Service, Washington, DC 20240. 2 Present address: U.S. Fish and Wildlife Service, Box 26A, Route 1, Fergus Falls, MN 56537. 894 J. Wildl. Manage. 46(4):1982 This content downloaded from 157.55.39.27 on Wed, 07 Sep 2016 06:34:55 UTC All use subject to http://about.jstor.org/terms AGE-CLASSES OF CANVASBACKS * Serie et al. 895 with statistical analysis of data; and H. F. Duebbert and D. H. Johnson for editorial review of the manuscript.

Corpora Lutea Variations of White-Tailed Deer

The reproductive tracts of 404 female white-tailed deer (Odocoileus virginianus) were studied for information on size, shape, and coloration of corpora lutea. Corpora lutea in fawns are regarded as regressing if they are less than 4.0 mm in diameter at the time when the rut for that age-class is nearing its end. In all age-groups of does where fetal membranes or embryos are present, corpora lutea smaller than 6.0 mm are regarded as regressing. These small ones are regarded as corpora lutea of an earlier heat and not as corpora lutea of the current pregnancy. Regressing corpora lutea of a previous ovulation also appear to have an irregular surface shape. Color is not a dependable criterion for differentiation of the two types of corpora lutea. During an investigation of reproduction in white-tailed deer in Iowa, information was obtained on the physical characteristics of their corpora lutea. In attempting to correlate fertilization rate with ovulation rate, difficulty has been encountered in differentiating corpora lutea of ovulation of a previous heat from corpora lutea of pregnancy. In sheep, corpora lutea of ovulation are formed in ruptured follicles within 4 days following ovulation (Asdell 1946:366-367) and are fully developed by the eighth day following ovulation (Harrison 1962:169). In deer, corpora lutea of ovulation begin regressing after about 14-15 days (Cheatum 1949:285) if fertilization does not occur. When fertilization and implantation take place, corpora lutea of ovulation persist as corpora lutea of pregnancy (Amoroso and Finn 1962:454). The corpus luteum has a glandular function, secreting progesterone hormone which is essential for implantation and early development of the fertilized ovum. This hormone also suppresses further follicular development and ovulation. After parturition, corpora lutea of pregnancy regress and become corpora albicantia. Ability to identify corpora lutea of ovution of a previous heat from those of pregnancy of a later heat would eliminate a possible source of error when using corpora lutea counts as an index to reproductive rates of deer. Golley (1957) found the use of the corpora lutea dependable for determining the ovulation incidence of the black-tailed deer (Odocoileus hemionus columbianus) but detected an error when using the corpora albicantia to indicate ovulation. Golley used histological techniques to determine the differences between the two types of tissue. This paper will discuss gross size, shape, and color variations of corpora lutea in white-tailed deer ovaries as a possible means for distinguishing the two types. The assistance of Eldie Mustard, former Iowa State Conservation Commission Biologist, is appreciated. Several of Iowas Conservation Commission officers and biologists also assisted materially by collecting reproductive tracts from wild deer. The cooperation of deer hunters who saved tracts for the study was indispensable. Calvin Rayburn, Ronald Schara, Harold Prince, and David Bolton, students 1Journal paper J-4604 of the Iowa Agricultural and Home Economics Experiment Station, Ames, Iowa. A contribution from the Iowa Cooperative Wildlife Research Unit, which is jointly sponsored by Iowa State University of Science and Technology, U. S. Bureau of Sport Fisheries and Wildlife, the Iowa State Conservation Commission, and the Wildlife Management Institute. Financial support for Trauger was provided by the National Science Foundation Undergraduate Research Participation Program.

Perspectives on The Wildlife Society's Economic Growth Policy Statement and the Development Process

Abstract On 18 September 2004, The Wildlife Society (TWS) published an official policy statement on economic growth and wildlife conservation. We believe this policy statement did not adequately address the issues. Thus, TWS missed an opportunity to lead the natural resource profession in refuting the fallacious rhetoric that “there is no conflict between economic growth and wildlife conservation” through the adoption of a strong policy statement on economic growth. Although we commend TWS Council for adopting a policy statement on economic growth, we believe the final wording contains several weaknesses. Here, we take a closer look at the statement and further evaluate how it might be strengthened in the future.

Response of Professional Societies and Conservation Organizations to Peak Oil and Economic Growth

Peaking of the world’s oil supply is resulting in economic, social, cultural, and environmental instability on a global level. Individuals, businesses, and entire countries are attempting to maintain economic growth and preserve our current way of life for as long as possible. Government attention is turned toward averting economic collapse and obtaining energy resources, while the people are concerned about job security and subsistence. Environmental concerns are receiving the least attention by the majority of people. The environment is being ravaged by an aggressive quest for more fossil fuel resources to support a growing population and sustain economic growth by a society that knows no other way to live and is utterly dependent on oil. Addressing current environmental problems is already a challenge for conservationists, because societal priorities reside elsewhere or resolving these issues directly impacts certain powerful economic interests. The environmental community, including many professional societies and conservation organizations, as well as a number of government agencies and private companies, will need to step up their efforts to address global impacts of oil depletion if they hope to continue to protect living natural systems and the environment. Unfortunately, societal capacity to support these vital efforts is diminishing due to the buildup of pervasive economic pressures from escalating higher costs of living in response to higher prices for energy.

Future Trends in Wildlife Conservation and Management Programs

Much of what we have to say in this chapter about future trends in wildlife conservation and management will be influenced by whether you are a technological or economic optimist or pessimist. If you are an optimist, we urge you to review thoroughly your entire framework for your optimism, particularly the laws of thermodynamics and our current economic system based upon unlimited growth. Energy is fundamental to human civilization and some forms cannot be easily substituted for others. Our modern industrial civilization is structured around nonrenewable fossil fuels. Being nonrenewable, each fossil fuel, whether coal, oil, or gas, has a certain life span that is dependent on the initial amount and rate of extraction. Extraction and depletion of these resources have certain characteristics. Oil, for instance, is characterized by an increase in rate of extraction, a peaking, and then a decrease, similar in shape to a bell curve. By some accounts, Peak Oil is already upon us. The peaking of world oil means that there will never again be as much oil extracted in subsequent years to meet current and future demands for it. The debate is not if it will happen, but when, and how we will deal with it. We always knew that this event would happen, as oil is a nonrenewable resource along with other fossil hydrocarbons, such as coal and natural gas, each having their own finite limits. We have built an entire global civilization on these nonrenewable resources at great cost to the environment and the biota inhabiting it. How will our fossil fuel dependency be dealt with as these fuels become scarce and more costly, both from a monetary and environmental aspect? Will we make a technological transition and substitute alternative energy sources at the requisite scale? Will we come up with a new source of cheap liquid fuel that is environmentally benign and that will allow us to continue this global civilization, or will we have to “powerdown” in ways presently unanticipated by most people? What will these events mean to contemporary wildlife conservation and management?

Envisioning an Alternative Future

As suggested 40 years ago, the limits to growth as measured by human consumption of net primary production (NPP) may well be reached in the next few decades. At that time, we will have reached the planetary limits to further growth in human activity. But, long before that point is reached, we will be faced with peaks in energy production and economic growth that directly impact human populations. Furthermore, our current industrial civilization powered by fossil fuels is changing Earth’s climate system and accelerating its loss of biodiversity and wildlife habitats. Due to demographic momentum, growth in human populations will continue for some time despite reduced reproductive rates in many developed parts of the world. There is little that can be done now to prevent world population from reaching almost 10 billion in 2050. Wealthy nations can work toward ecological sustainability and international stability by reducing material consumption and stabilizing their populations. Nations with widespread poverty can help encourage, through diplomatic means, this transition of wealthy nations while pursuing truly needed levels of economic growth in their own countries. Although “contraction and convergence” are far from politically viable in the early twenty-first century, some degree of both—contraction of the global economy and convergence of per capita consumption—is perhaps the only sustainable option in international affairs, and offers a basic element of fairness in the context of global limits to growth.

Arthur S. Hawkins, 1914–2006

Arthur S. Hawkins (Art), a pioneer and international leader in waterfowl research and management, died 9 March 2006, at his home near Hugo, Minnesota. At the age of 92, Art left this world with binoculars around his neck and walking sticks in hand, doing what he enjoyed most, walking around his farm to observe the arrival of early migrant birds. He kept meticulous records of his field observations over the years, and a daily journal beginning in 1957, with the last entry on 8 March 2006; ‘‘Didn’t freeze last night. Saw a pair of mallards at 8:30, feeding.—turkey tracks near the barn and pheasant tracks near the bench—.’’ Born in Batavia, New York, USA, Art loved hunting, fishing, and trapping as a boy, outdoor passions that led him to seek a career in natural resources management. He completed undergraduate studies at Cornell University in 1934 and obtained his Master of Science degree at the University Wisconsin in 1937. There he worked on a bobwhite quail project as one of the early students of Aldo Leopold. After college, Art began work with the Illinois Natural History Survey in 1938, where he was introduced to emerging waterfowl and wetland problems of that era by Frank Bellrose, who became a lifelong professional colleague and personal friend. Together, they conducted initial studies on the development of artificial nesting structures for wood ducks and laid the groundwork for waterfowl population surveys and determination of annual hunter kill of ducks along the Mississippi River. Upon returning in 1945 from 4 years in the United States Army during World War II, Art continued his waterfowl work with the Illinois Natural History Survey. In 1946 Art took a job with the United States Fish and Wildlife Service (USFWS) as one of the first flyway biologists, where he became one of the pioneers who helped develop the concept for formation of the Flyway Council System. Beginning in 1948, he was instrumental in organizing the Mississippi Flyway Waterfowl Committee, which subsequently led to the formation of the Mississippi Flyway Council in January 1952, followed by the Technical Section in January 1953. He became the Service’s Mississippi Flyway Representative in 1953. He spent the next 8 years working seasonally on waterfowl production studies and wetland relationships in Manitoba, Canada. There, in cooperation with the Canadian Wildlife Service, Manitoba Wildlife Branch, and the Delta Waterfowl Research Station, he worked with another of Leopold’s students, H. Albert Hochbaum, then Director of the Delta Research Station. In addition to his initial field work in Canada, Art immediately began promoting the need for Flyway Management Plans, and initiated work on the Mississippi Flyway Management Plan in 1953, which was completed in 1958. Then he began to encourage the preparation of species management plans, several of which were completed, including a plan for midcontinent mallards and plans for specific Canada goose populations or flocks. He was a leader in attempts to improve harvest management of Canada goose populations in the Mississippi Flyway. He was a strong advocate of good sportsmanship and believed that hunters were a dimension of game management too often forgotten in professional circles. He maintained that hunting pressure could be controlled, while maintaining high standards of quality and satisfaction among hunters. Right up to the time he retired in 1974, he was a tireless supporter of species management, international cooperation, and esthetic values of game management. He continued to work as a reemployed annuitant for USFWS until the mid1980s. In retirement he continued to be active in a variety of environmental and resource management issues in Minnesota and Wisconsin, and played a strong role in formation of the Wood Duck Society in 1985, and the Leopold Education Project. Based on early relationships, Art was a strong advocate of Leopold’s ‘‘Land Ethic’’ philosophy and applied many conservation practices to his farm, lake, and marshes in Minnesota. In spite of his busy schedule over the years, Art always took time to promote the concept of sound management based on good science, and he was a prolific writer. He was the author or coauthor more than 150 technical papers, numerous management plans, and a great variety of project reports and news articles. He was a contributor to the book Waterfowl Tomorrow (1964), and was the leader of the Editorial Committee for the book Flyways—Pioneering Waterfowl Management in North America (1984), both published by the United States Department of the Interior Fish and Wildlife Service. The walls of his office and home were adorned with significant awards recognizing his many accomplishments. Over a period of 65 years, he influenced the lives of many people working in the field of natural resources research and management. Those of us who had the opportunity to work in the field with Art soon learned that work began at daylight and ended at dark, weather and endurance permitting. We quickly learned Art’s survival technique by putting a peanut butter sandwich in our hind pocket to get us through the day. He was an inspiration and role model for young and old alike, and an important mentor to all who sought his advice and wisdom. He was well read on many current conservation topics and his enthusiasm for debate was infectious. He certainly earned his recognition as one of the pioneers in waterfowl management in North America and was a legend within the migratory bird fraternity. He was still active in these circles at age 92, and expressed his DOI: 10.2193.2006-517