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Full-Text Articles in Behavior and Ethology

Land Use Status And Trends Of Potential Whooping Crane Release Sites In Central Florida, Mary Anne Bishop Jan 1992

Land Use Status And Trends Of Potential Whooping Crane Release Sites In Central Florida, Mary Anne Bishop

Proceedings of the North American Crane Workshop

Three areas in central Florida, identified as potential sites for the reintroduction of a nonmigratory flock of whooping cranes (Grus americana), were evaluated. and ranked as to their priority for reintroduction based on their land use status and trends. The Kissimmee Prairie, including Three Lakes Wildlife Management Area, Prairie-Lakes State Preserve, and the National Audubon Society's Kissimmee Prairie Sanctuary was ranked first, the Webb Wildlife Management Area second, and Myakka River State Park third. Primary criteria used for each site and its surrounding lands included acreage, ownership, management, public use, access, potential threats, and the potential to support …


Relationship Of Channel Maintenance Flows To Whooping Crane Use Of The Platte River, Craig A. Faanes, David B. Bowman Jan 1992

Relationship Of Channel Maintenance Flows To Whooping Crane Use Of The Platte River, Craig A. Faanes, David B. Bowman

Proceedings of the North American Crane Workshop

Periodic high flows in the Platte River are necessary to scour vegetation and redistribute sediment in the stream channel. Peak and mean annual flows have been reduced by as much as 70% from pre-development times, but channel maintenance flows still occur, although at a much reduced frequency and magnitude of occurrence. Use of the Platte River by migrant whooping cranes (Grus americana) in recent years appears to be related to the recent occurrence of flows in excess of 8,000 cfs for 5 or more consecutive days.


Release Of Sandhill Crane Chicks Hand-Reared With Artificial Stimuli, Robert H. Horwich, John Wood, Ray Anderson Jan 1992

Release Of Sandhill Crane Chicks Hand-Reared With Artificial Stimuli, Robert H. Horwich, John Wood, Ray Anderson

Proceedings of the North American Crane Workshop

Greater sandhlll crane chicks (Grus canadensis tabida) were hand-reared using moveable puppets and vocalizing crane models as substitute parents. Their parental attachment was transferred to a crane-costumed human who introduced them to a wild environment and to wild foods. Five chicks were gentle-released in Wisconsin when 3.5 months old, a period of high sociality, and all successfully joined wild cranes. Following their first few weeks in association with wild cranes, their behavior was normal and comparable to that of wild chicks and they achieved normal flight distance from humans. Four of the 5 were relocated in Wisconsin the …


Whooping Cranes At The San Antonio Zoo, Jacqueline A. Lauver Jan 1992

Whooping Cranes At The San Antonio Zoo, Jacqueline A. Lauver

Proceedings of the North American Crane Workshop

Since April, 1956, when an injured whooping crane (Grus americana) was received for rehabilitation, the San Antonio Zoo has maintained these birds in the collection and is 1 of only 2 zoos to have raised them. The zoo's management efforts, combined with favorable climatic cbnditions and water sources have contributed to a successful breeding program. The whooping crane is 1 of 7 crane species successfully bred, and 1 of 8 crane species currently in the collection.


The Contingency Plan For Federal-State Cooperative Protection Of Whooping Cranes, James C. Lewis Jan 1992

The Contingency Plan For Federal-State Cooperative Protection Of Whooping Cranes, James C. Lewis

Proceedings of the North American Crane Workshop

A "Contingency Plan for Federal-State Cooperative Protection of Whooping Cranes" was developed in 1985 to protect migrating whooping cranes (Grus americana). Thirteen states and the U.s. Fish and Wildlife Service implemented the plan in summer 1985. One state and one feq,eral employee, and alternates, are appointed as the "key contact" individuals within each state. Reports of sightings of whooping cranes are forwarded to these key contacts and they coordinate the response to sightings. An important part of the plan is education activities designed to increase the public's ability to identify whooping cranes and to encourage the reporting of …


Introduction Of Whooping Cranes In Eastern North America, James C. Lewis, F. Graham Cooch Jan 1992

Introduction Of Whooping Cranes In Eastern North America, James C. Lewis, F. Graham Cooch

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) historically occurred throughout most of North America. A migration route last used prior to 1857 crossed the Appalachians to Atlantic Coast wintering grounds in coastal areas of New Jersey, South Carolina and river deltas farther south. The species disappeared from most eastern North American locations in the late 1800's. The winter 1987 population consisted of 43 captive birds and 154 in 2 wild subpopulations. Pursuant to both Canadian and u.s. recovery plans, sites in Michigan-Ontario, Georgia and Rorida are being considered as potential release locations for establishing an eastern population. Cross-fostering, gentle release and …


Mate Recognition And Fidelity In Captive Sandhill Cranes, Peter W. Shannon Jan 1992

Mate Recognition And Fidelity In Captive Sandhill Cranes, Peter W. Shannon

Proceedings of the North American Crane Workshop

Two pairs of greater sandhill cranes (Grus canadensis tabida) were maintained at Audubon Park Zoo in separate but adjacent exhibits. The male of pair #2 was killed and due to medical problems associated with the female of pair #1, male #1 and female #2 were placed together. These birds subsequently bonded but did not nest. Following a 17 month separation, female #1 was moved to an area where she could hear but not see male #1 and female #2 . Almost immediately, male #1 began attempting to move himself closer to female #1 . They were placed together, …


Whooping Crane Habitat Alteration Analysis At Aransas National Wildlife Refuge, Texas, C. Lee Sherrod, Richard Medina Jan 1992

Whooping Crane Habitat Alteration Analysis At Aransas National Wildlife Refuge, Texas, C. Lee Sherrod, Richard Medina

Proceedings of the North American Crane Workshop

Aquatic, wetland, and upland habitat changes were quantified within the approximate critical habitat of the endangered whooping crane (Grus americana) along the Gulf Intracoastal Waterway (GIWW) through Aransas National Wildlife Refuge and San Antonio, Bay, Texas. Study procedures employed comparative analysis of pre-GIWW (1930) and present (1986) aerial photography to provide a basis for the assessment of positive and negative impacts of the construction, operation and maintenance of the GIWW, principally on the whooping crane, but also on biota in general. Thirteen habitat mapping categories were utilized to describe an approximately 1,830 m wide corridor along the GIWW …


Lead Poisoning In A Whooping Crane, S. Bret Synder, Michael J. Richard, John P. Thilsted, Roderick C. Drewien, James C. Lewis Jan 1992

Lead Poisoning In A Whooping Crane, S. Bret Synder, Michael J. Richard, John P. Thilsted, Roderick C. Drewien, James C. Lewis

Proceedings of the North American Crane Workshop

The first known incident of lead poisoning in a whooping crane (Grus americana) occurred as the affected bird completed its second migration from Grays Lake National Wildlife Refuge (NWR), Idaho to Bosque del Apache NWR, New Mexico. It fell ill about 4 1/2 weeks after reaching the winter site and was captured. The bird exhibited signs of anorexia and starvation, weakness with drooped wings, greenish watery diarrhea and an unusual gaping of the mouth with abnormal swallowing motions. Blood showed marked polychromasia (>50%) and reticulocytosis (>80%) of RBC's. Serum chemistry values were not diagnostic. A radiograph …


Crane Migration In Northern New Mexico, Dale W. Stahlecker Jan 1992

Crane Migration In Northern New Mexico, Dale W. Stahlecker

Proceedings of the North American Crane Workshop

Greater sandhill cranes (Grus canadensis tabida) and foster-reared whooping cranes (G. americana) were monitored on a 345 km migration between their traditional stopover in southcentral Colorado and their winter grounds in central New Mexico during 4 autumns (1984-87) and 1 spring (1985). Autumn sandhill crane counts totaled 17,363 in 1984, 9,317 in 1985, 29,053 in 1986, and 26,552 in 1987. Peak flights of over 7,000 cranes in 1 day were recorded in both 1986 and 1987. More than 50% of the cranes were counted on just 4 days in 1984, 1986 and 1987. At least 27% …


Nesting Of Greater Sandhill Cranes On Seney National Wildlife Refuge, Richard P. Urbanek, Theodore A. Bookhout Jan 1992

Nesting Of Greater Sandhill Cranes On Seney National Wildlife Refuge, Richard P. Urbanek, Theodore A. Bookhout

Proceedings of the North American Crane Workshop

During 1987, 59 nests of 57 pairs of greater sandhill cranes (Grus canadensis tabida) were located, mainly from the air, on or near the Seney National Wildlife Refuge, Michigan, and 52 nests were ground-checked. Nests were in available palustrine classes without tree canopies. Only 19% were in Sphagnum bogs, in which most nests from other areas of the Upper Peninsula have been found. Cattail (Typha latifolia) marshes, most prevalent in the managed area of the refuge, contabed 44% of the nests, and sedge (Carex spp.) marshes accounted for 37%. Important co-dominant plant species were leatherleaf …


Renesting Of Mississippi Sandhill Cranes In Jackson County, Mississippi 1965–1989, Jacob M. Valentine Jr. Jan 1992

Renesting Of Mississippi Sandhill Cranes In Jackson County, Mississippi 1965–1989, Jacob M. Valentine Jr.

Proceedings of the North American Crane Workshop

Among 118 active nests of Mississippi sandhill cranes (Grus canadensis pulla) in Jackson County, Mississippi, 1%5-1989, 13 were renests. Three chicks from 19 wild and 3 from 3 Patuxent Wildlife Research Center (PWRC) switched eggs hatched in 13 first nests, but 5 died early and 1 after 2 weeks. Ten eggs were dead (infertile or the embryos died) in or at the nest. Two clutches (3 eggs) were destroyed by mammalian predators, 2 eggs were taken for captive propagation, and 1 was pecked and destroyed by the crane pair. Three chicks hatched from 22 wild eggs and 1 …


The Study Of Relatedness And Genetic Diversity In Cranes, George F. Gee, Herbert C. Dessauer, Jonathan Longmire, W. Elwood Briles, Raymond C. Simon Jan 1992

The Study Of Relatedness And Genetic Diversity In Cranes, George F. Gee, Herbert C. Dessauer, Jonathan Longmire, W. Elwood Briles, Raymond C. Simon

Proceedings of the North American Crane Workshop

The U.S. Fish and Wildlife Service (Service) is responsible for recovery of endangered species in the wild and, when necessary, maintenance in captivity. These programs provide an immediate measure of insurance against extinction. A prerequisite inherent in all of these programs is the preservation of enough genetic diversity to maintain a viable population and to maintain the capacity of the population to respond to change. Measures of genetic diversity examine polymorphic genes that are not influenced by selection pressures. Examples of these techniques and those used to determine relatedness are discussed. Studies of genetic diversity, electrophoresis of blood proteins, relatedness, …


Introgression Of Coyote Mitochondrial Dna Into Sympatric North American Gray Wolf Populations, Niles Lehman, Andrew Eisenhawer, Kimberly Hansen, L. David Mech, Rolf O. Peterson, Peter J. P. Gogan, Robert K. Wayne Jan 1991

Introgression Of Coyote Mitochondrial Dna Into Sympatric North American Gray Wolf Populations, Niles Lehman, Andrew Eisenhawer, Kimberly Hansen, L. David Mech, Rolf O. Peterson, Peter J. P. Gogan, Robert K. Wayne

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Mitochondrial DNA (mtDNA) genotypes of gray wolves and coyotes from localities throughout North America were determined using restriction fragment length polymorphisms. Of the 13 genotypes found among the wolves, 7 are clearly of coyote origin, indicating that genetic transfer of coyote mtDNA into wolf populations has occurred through hybridization. The transfer of mtDNA appears unidirectional from coyotes into wolves because no coyotes sampled have a wolf-derived mtDNA genotype. Wolves possessing coyote-derived genotypes are confined to a contiguous geographic region in Minnesota, Ontario, and Quebec, and the frequency of coyote- type mtDNA in these wolf populations is high (> 500%). The …


Wolf Population Survival In An Area Of High Road Density, L. David Mech Apr 1989

Wolf Population Survival In An Area Of High Road Density, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Wolf mortality in a high-road-density area of Minnesota exceeds that in an adjacent wilderness, and is primarily human-caused. The wolf population there is maintained primarily by ingress from the adjacent wilderness areas. A road density of 0.58 km/km2 can be exceeded and the area still support wolves if it is adjacent to extensive roadless areas.


Wolf Distribution And Road Density In Minnesota, L. David Mech, Steven H. Fritts, Glenn L. Radde, William J. Paul Jan 1988

Wolf Distribution And Road Density In Minnesota, L. David Mech, Steven H. Fritts, Glenn L. Radde, William J. Paul

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Distribution of the wolf (Canis lupus) in parts of Wisconsin (Thiel 1985) and Michigan and Ontario (Jensen et al. 1986) has been related to the density of roads passable by 2-wheel-drive vehicles. Wolves in those regions generally do not occur where road densities exceed 0.58 km/km2, whereas similar areas nearby with fewer roads do contain wolves.

In a small segment of the wolf range in Minnesota, wolves did not have territories where roads exceeded a density of 0.73 km/km2 (T. K. Fuller, Minnesota Department of Natural Resources, unpublished data). In another small area of Minnesota …


Mortality Of White-Tailed Deer In Northeastern Minnesota, Michael E. Nelson, L. David Mech Oct 1986

Mortality Of White-Tailed Deer In Northeastern Minnesota, Michael E. Nelson, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Abstract: Two hundred nine white-tailed deer (Odocoileus virginianus) were radiotracked in the central Superior National Forest, Minnesota, from 1973 through winter 1983-84; 85 deaths were recorded. Annual survival was 0.31 for fawns (<1.0 years old), 0.80 for yearling (1.0-2.0 years old) females, 0.41 for yearling males, 0.79 for adult (≥2.0 years old) females, and 0.47 for adult males. Monthly survival rates were high from May through December (0.94-1.00), except for yearling (0.60) and adult (0.69) bucks during the November hunting season. Most mortality occurred from January through April when gray wolf (Canis lupus) predation was an important mortality source for all cohorts. Yearlings males were most vulnerable to hunting and adult males to wolf predation.


Relationship Between Snow Depth And Gray Wolf Predation On White-Tailed Deer, Michael E. Nelson, L. David Mech Jul 1986

Relationship Between Snow Depth And Gray Wolf Predation On White-Tailed Deer, Michael E. Nelson, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Abstract: Survival of 203 yearling and adult white-tailed deer (Odocoileus virginianus) was monitored for 23,441 deer days from January through April 1975-85 in northeastern Minnesota. Gray wolf (Canis lupus)predation was the primary mortality cause, and from year to year during this period, the mean predation rate ranged from 0.00 to 0.29. The sum of weekly snow depths/month explained 51% of the variation in annual wolf predation rate, with the highest predation during the deepest snow.


Activity Levels Of Arboreal Rodents Peromysus And Ochrotomys Evaluated With Nest Cans In Seasonally Flooded Forests, John W. Walke Jul 1984

Activity Levels Of Arboreal Rodents Peromysus And Ochrotomys Evaluated With Nest Cans In Seasonally Flooded Forests, John W. Walke

Biological Sciences Theses & Dissertations

The diversity and density of small mammals in the Dismal Swamp are believed to be small. To test this, four 1.96 ha grids were established and operated in the Dismal Swamp National Wildlife Refuge, from September 1981 to November 1982. Number 10 metal cans covered with plastic lids were placed as nest boxes at 0.5 to 1.5 m height on trees. A 2.5 cm hole allowed access by arboreal rodents, to each nest can. The activity level of the two arboreal rodents, Peromyscus leucopus and Ochrotomys nuttalli, was evaluated by observing types of activity ranging from presence of mice to …


Simulation Analyses Of Space Use: Home Range Estimates, Variability, And Sample Size, Marc Bekoff, L. David Mech Jan 1984

Simulation Analyses Of Space Use: Home Range Estimates, Variability, And Sample Size, Marc Bekoff, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Simulations of space use by animals were run to determine the relationship among home range area estimates, variability, and sample size (number of locations). As sample size increased, home range size increased asymptotically, whereas variability decreased among mean home range area estimates generated by multiple simulations for the same sample size. Our results suggest that field workers should ascertain between 100 and 200 locations in order to estimate reliably home range area. In some cases, this suggested guideline is higher than values found in the few published studies in which the relationship between home range area and number of locations …


Aspects Of The Nesting Ecology Of Least Terns And Piping Plovers In Central Nebraska, Craig A. Faanes Dec 1983

Aspects Of The Nesting Ecology Of Least Terns And Piping Plovers In Central Nebraska, Craig A. Faanes

Papers in Ornithology

Breeding habitat of the least tern is made up primarily of coastal beaches and inland river sandbars. Populations of the interior (Sterna antillarum athalassos) and east coast (S. a. antillarum) subspecies are now declining (Marshall et al. 1975, Duffy 1977, Jernigan et al. 1978) and the western subspecies (S. a. browni) is endangered (Wilbur 1974). Although coastal populations have received considerable attention (Wolk 1974, Atwood et al. 1977, Blodgett 1978), little research has been conducted on the interior race (Hardy 1957, Downing 1975).

The piping plover inhabits river sandbars and sand beaches and, like …


An Analysis Of Howling Response Parameters Useful For Wolf Pack Censusing, Fred H. Harrington, L. David Mech Jul 1982

An Analysis Of Howling Response Parameters Useful For Wolf Pack Censusing, Fred H. Harrington, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Gray wolves (Canis lupus) were studied from April 1972 through April 1974 in National Forest in northeastern Minnesota by radio-tracking and simulated howling. Based during 217 of 456 howling sessions, the following recommendations were derived for using howling as a census technique: (1) the best times of day are dusk and night; (2) July, August, and are the best months; (3) precipitation and winds greater than 12 km/hour should be avoided; (of 5 single howls should be used, alternating "flat" and "breaking" howls; (5) trials should 3 times at about 2-minute intervals with the first trial at lower …


Dynamics, Movements, And Feeding Ecology Of A Newly Protected Wolf Population In Northwestern Minnesota, Steven H. Fritts, L. David Mech Oct 1981

Dynamics, Movements, And Feeding Ecology Of A Newly Protected Wolf Population In Northwestern Minnesota, Steven H. Fritts, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The gray wolf Canis lupus occupies only about 1 percent of its former range in the lower 48 states (Mech 1974a). Most of the range is in northern Minnesota, where the resident population is classified as "threatened" by the U.S. Department of the Interior. Wolves have been and will continue to be the subject of considerable controversy in Minnesota.

The first scientific study of wolves in Minnesota was conducted by Olson (1938a,b). That and all subsequent re- search was in the Superior National Forest (SNF) of northeastern Minnesota even though wolves inhabit approximately the northern third of the state. Consequently, …


Deer Social Organization And Wolf Predation In Northeastern Minnesota, Michael E. Nelson, L. David Mech Jul 1981

Deer Social Organization And Wolf Predation In Northeastern Minnesota, Michael E. Nelson, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The white-tailed deer Odocoileus virginianus has been subject to intensive research and management, yet we are just beginning to understand its social organization. Little is known about home range formation, migration, social bonds, and traditions in this deer, what functions they serve, and what selective forces have affected them.

Predation by wolves Canis lupus, in particular, has not been examined as a factor in deer evolution, yet the intimate interactions between deer and wolf through the millennia no doubt strongly influenced major morphological and behavioral adaptations in both species. It is a reasonable assumption that wolf predation has been …


Population Regulation In Wolves, Jane M. Packard, L. David Mech Jan 1980

Population Regulation In Wolves, Jane M. Packard, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The possibility of social regulation of wolf populations has been discussed in the literature for several years. Some of the first ecological studies of wolves indicated that their populations did not increase as rapidly as was theoretically possible, and that they reached a saturation point apparently not set by food. Subsequent captive studies demonstrated the existence of social mechanisms possibly capable of regulating population growth. However, the importance of these factors in wild populations has not been established. This paper has four objectives: (1) to evaluate the existing concept of "intrinsic limitation," (2) to propose that wolf population dynamics may …


Wolf Howling And Its Role In Territory Maintenance, Fred H. Harrington, L. David Mech Jan 1979

Wolf Howling And Its Role In Territory Maintenance, Fred H. Harrington, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The wolf (Canis lupus) is a wide-ranging social carnivore with a complex spatial organization (MECH, 1972; 1973). The precise manner in which this organization is maintained is unknown, but territory advertisement using olfactory and acoustic modes seems to be involved.

The acoustic mode includes primarily howling. Within a wolf pack, howling may be useful to reassemble separated members (MECH, 1966; THEBERGE & FALLS, 1967), and may communicate information on individual identity, location, and other behavioral and environmental contingencies (THEBERGE & FALLS, 1967). Between packs, however, howling may serve to advertise territory, communicating the locations of packs and thus …


A Mid-Continent Irruption Of Canada Lynx, 1962-63, Harvey L. Gunderson Sep 1978

A Mid-Continent Irruption Of Canada Lynx, 1962-63, Harvey L. Gunderson

University of Nebraska State Museum: Mammalogy Papers

There was a mid-continent irruption of the Canada lynx (Felis lynx) population and subsequent extensive movement into non-lynx habitats during the years 1962-1963. Lynx were found in the prairie provinces of Canada and the prairie areas of Minnesota, and North and South Dakota. They were also found in urban areas such as Minneapolis and St. Paul, Minnesota: Winnipeg, Manitoba: and Calgary, Saskatchewan, Canada. Causes for the irruption remain unknown but speculations include primarily a change in snowshoe hare population, disease, extensive forest fires and extensive spraying. Unusual behavior seemed to be most often reflected by a lack of …


Relating Wolf Scat Content To Prey Consumed, Theodore J. Floyd, L. David Mech, Peter A. Jordan Jan 1978

Relating Wolf Scat Content To Prey Consumed, Theodore J. Floyd, L. David Mech, Peter A. Jordan

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

In 9 trials, captive wolves (Canis lupus) were fed prey varying in size from snowshoe (Lepus americanus) to adult deer (Odocoileus virginianus), and the resulting scats were counted. collectible scats were distinguished from liquid, noncollectible stools. In collectible scats, the small prey occurred in greater proportion relative to the prey's weight, and in lesser proportion to the prey's numbers, than did the remains of larger prey. A regression equation with an excellent the data (r2 = 0.97) was derived to estimate the weight of prey eaten per collectible scat for With this information …


Productivity, Mortality, And Population Trends Of Wolves In Northeastern Minnesota, L. David Mech Nov 1977

Productivity, Mortality, And Population Trends Of Wolves In Northeastern Minnesota, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Population parameters, mortality causes, and mechanisms of a population decline were studied in wolves (Canis lupus lycaon) from 1968 to 1976 in the Superior National Forest. The main method was aerial radio-tracking of 129 wolves and their packmates. Due to a decline in white-tailed deer (Odocoileus virginianus), the wolf population decreased during most of the study. Average annual productivity varied from 1.5 to 3.3 pups per litter, and annual mortality rates from 7 to 65 percent. Malnutrition and intraspecific strife accounted equally for 58 percent of the mortality; human causes accounted for the remainder. As wolf …


Wolf-Pack Buffer Zones As Prey Reservoirs, L. David Mech Oct 1977

Wolf-Pack Buffer Zones As Prey Reservoirs, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Abstract. In a declining herd, surviving deer inhabited overlapping edges of wolf- pack territories. There, wolves hunted little until desperate, in order to avoid fatal encounters with neighbors. Such encounters reduce wolf numbers and predation pressure and apparently allow surviving deer along territory edges to repopulate the area through dispersal of their prime, less vulnerable offspring into territory cores.