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Articles 631 - 660 of 903

Full-Text Articles in Terrestrial and Aquatic Ecology

An Obligation To Publish, Stephen A. Nesbitt Jan 2005

An Obligation To Publish, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

To be justifiable any wildlife study should strive to attain and describe new knowledge or refine existing understanding. Published results of field studies are often the products that conclude the study, though not always. But, as E.O. Wilson wrote in Consiliance: The Unity of Knowledge, “One of the structures of the scientific ethos is that a discovery does not exist until it is safely reviewed and in print.” Putting knowledge to page requires effort and, frequently, the abandonment of ones own ego. However, ego notwithstanding, this is not the only reason to publish research findings. Whether we are trying to …


Injuries And Abnormalities Of Sandhill Cranes Captured In Florida, Stephen A. Nesbitt, Marilyn G. Spalding, Stephen T. Schwikert Jan 2005

Injuries And Abnormalities Of Sandhill Cranes Captured In Florida, Stephen A. Nesbitt, Marilyn G. Spalding, Stephen T. Schwikert

Proceedings of the North American Crane Workshop

Observations of gross pathological abnormalities were made during handling of sandhill cranes (Grus canadensis) captured for banding in Florida. One hundred fifty-six of 1,331 (11.7%) cranes examined showed evidence of one or more anomalies that were the result of disease, congenital deformity, or injury. Most frequent were abnormalities of the legs and feet, followed by abnormalities of the bill. Injuries of the eyes, head, and neck were also noted. Many of these birds were observed subsequent to banding and survived for several years with their injuries, though some never succeeded in reproducing.


International Crane Foundation Sponsored Environmental Education: Conservation Of The Cuban Sandhill Crane, Korie M. Klink Jan 2005

International Crane Foundation Sponsored Environmental Education: Conservation Of The Cuban Sandhill Crane, Korie M. Klink

Proceedings of the North American Crane Workshop

The International Crane Foundation (ICF) has supported crane conservation, education and research activities in Cuba since 1995. Groups of American educators and researchers visit the island, contributing to annual crane festivals, school activities, survey work, assessments and cross-cultural communication. The goals of ICF’s environmental education program in Cuba are to: Disseminate information about ICF and crane conservation to American and Cuban educators and students, and to empower them to carry on ICF’s mission in their classrooms and communities; Participate actively in the Cuban Crane Festival while interacting with and supporting Cuban educators, biologists, and professionals; Develop activities, educational programs and …


Genetic Assessment Of Non-Migratory Sandhill Crane Populations, K. L. Jones, F. Chavez-Ramirez, X. Galvez-Aguilera, L. Torella, M. V. Ashley Jan 2005

Genetic Assessment Of Non-Migratory Sandhill Crane Populations, K. L. Jones, F. Chavez-Ramirez, X. Galvez-Aguilera, L. Torella, M. V. Ashley

Proceedings of the North American Crane Workshop

Partial migration, the tendency of a segment of a population to remain resident while others migrate between their seasonal breeding and wintering ranges, is well known for many bird species. The objective of this study is to quantify the population structure and historical and recent gene flow patterns among non-migratory sandhills using microsatellite DNA genotyping of a large number of sandhills collected from six populations; and to assess if the population subdivisions are consistent with theories of partial migration. Our results indicate a complex web of gene flow within non-migratory populations, as well as between migratory and non-migratory populations. Gene …


Proceedings Of The Ninth North American Crane Workshop, January 17–20, 2003, Table Of Contents Jan 2005

Proceedings Of The Ninth North American Crane Workshop, January 17–20, 2003, Table Of Contents

Proceedings of the North American Crane Workshop

No abstract provided.


Reintroduction Techniques: Post-Release Performance Of Sandhill Cranes (1) Released Into Wild Flocks And (2) Led On Migration By Ultralight Aircraft, Richard P. Urbanek, Joseph W. Duff, Scott R. Swengel, Lara E. A. Fondow Jan 2005

Reintroduction Techniques: Post-Release Performance Of Sandhill Cranes (1) Released Into Wild Flocks And (2) Led On Migration By Ultralight Aircraft, Richard P. Urbanek, Joseph W. Duff, Scott R. Swengel, Lara E. A. Fondow

Proceedings of the North American Crane Workshop

Two methods of reintroducing a migratory population of whooping cranes (Grus americana) were tested with costume/ isolation-reared juvenile greater sandhill cranes (G. canadensis tabida): (1) release into wild flocks during autumn staging and (2) leading on autumn migration by ultralight aircraft. Birds in the first group were released singly, and all integrated quickly into the wild flocks and adopted similar behavioral patterns. Birds in the second group were led to winter on an inland site on the Gulf Coast of Florida. Most of the birds led by ultralight aircraft remained in their juvenile cohort through the …


Sandhill Crane Use Of Managed Chufa Wetlands In New Mexico, John P. Taylor, Loren M. Smith Jan 2005

Sandhill Crane Use Of Managed Chufa Wetlands In New Mexico, John P. Taylor, Loren M. Smith

Proceedings of the North American Crane Workshop

Natural wetland food plants help meet energetic requirements for sandhill cranes (Grus canadensis). Chufa (Cyperus esculentus) tubers were found to be a prominent item in the winter diet of cranes in New Mexico and Texas. In 1996 and 1997, chufa production was compared among mowing, discing, and sustained-flooding treatments intended to enhance chufa tuber growth. Sandhill crane numbers were monitored on wetlands during winter flooding to determine treatment preferences. No differences in sandhill crane use of treated wetlands were found in 1996, however in 1997, crane use was higher on disked field than sustained flood fields …


An Adaptive Approach To Channel Management On The Platte River, Kent Pfeiffer, Paul Currier Jan 2005

An Adaptive Approach To Channel Management On The Platte River, Kent Pfeiffer, Paul Currier

Proceedings of the North American Crane Workshop

The mission of the Platte River Whooping Crane Maintenance Trust is to protect and manage habitat in the Platte valley for whooping cranes, sandhill cranes, and other migratory birds. The plan for meeting this mission calls for the creation and maintenance of eleven habitat complexes distributed through the central Platte valley. Each habitat complex is intended to consist of 1,000 ha of wet meadows and adjacent roost habitat of open, unvegetated river channel. Reduced flows in the river have caused its channel to narrow with banks that are often heavily wooded. Formerly mobile sand bars have stabilized and support dense …


Migration Chronology, Routes, And Distribution Of Pacific Flyway Population Lesser Sandhill Cranes, Michael J. Petrula, Thomas C. Rothe Jan 2005

Migration Chronology, Routes, And Distribution Of Pacific Flyway Population Lesser Sandhill Cranes, Michael J. Petrula, Thomas C. Rothe

Proceedings of the North American Crane Workshop

Managers of migratory game birds require accurate information about bird movements to delineate populations, protect important habitats, and regulate harvest. Data describing movements of sandhill cranes (Grus canadensis) belonging to the Pacific Flyway Population (PFP) are lacking. We used satellite telemetry to monitor movements of PFP lesser sandhill cranes (Grus c. canadensis) captured in the upper Cook Inlet and Bristol Bay regions of Alaska. Satellite transmitters were deployed on 19 flightless young (colts) and 3 adults over 3-years (2000-2002). Chronology, routes, and stopover or staging areas were identified for fall and spring migration periods. On average, …


Decline And Recovery Of A High Arctic Wolf-Prey System, L. David Mech Jan 2005

Decline And Recovery Of A High Arctic Wolf-Prey System, L. David Mech

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

A long-existing system of wolves (Canis lupus), muskoxen (Ovibos moschatus), and arctic hares (Lepus arcticus) in a 2600 km2 area of Canada’s High Arctic (80° N latitude) began collapsing in 1997 because of unusual adverse summer weather but recovered to a level at which all three species were reproducing by 2004. Recovery of wolf presence and reproduction appeared to be more dependent on muskox increase than on hare increase.

Un vieux système biologique composé de loups (Canis lupus), de boeufs musqués (Ovibos moschatus) et de lièvres arctiques (Lepus …


Bears Remain Top Summer Predators, Shannon M. Barber, L. David Mech, P. J. White Jan 2005

Bears Remain Top Summer Predators, Shannon M. Barber, L. David Mech, P. J. White

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

In the ten years since wolves (Canis lupus) were restored to Yellowstone National Park (YNP), elk (Cervus elaphus) numbers have substantially decreased. The northern range elk herd is the largest elk herd in Yellowstone, and constitutes the majority of the park’s elk population. During 1994–2005, early winter counts of northern Yellowstone elk decreased from 19,045 to 9,545. Also, during winters 2000–2004, calf:cow ratios declined from 29:100 to 12:100, and were among the lowest recorded during the past several decades. Though many factors (e.g., predation, hunting, and drought) likely contributed to this decreasing abundance and low recruitment, …


Strong Interactions Between Juvenile Caribbean Spiny Lobster (Panulirus Argus) And Caribbean Reef Octopus (Octopus Briareus) In The Florida Keys, Jennifer Anne Lear Oct 2004

Strong Interactions Between Juvenile Caribbean Spiny Lobster (Panulirus Argus) And Caribbean Reef Octopus (Octopus Briareus) In The Florida Keys, Jennifer Anne Lear

Biological Sciences Theses & Dissertations

Coexisting species may simultaneously compete for resources and interact as predator and prey, creating a strong interaction that can alter the structure of animal communities. This type of interaction potentially occurs between juvenile Caribbean spiny lobster (Panulirus argus) and Caribbean reef octopus (Octopus briareus) within hard-bottom habitats in the Florida Keys, FL (USA), where octopuses may consume juvenile lobsters and also compete with them for limited crevice shelters. I conducted a series of field and mesocosm studies to investigate the nature of octopus-lobster interactions and their implications for the structure of their populations in the wild. …


Unusual Behavior By Bison, Bison Bison, Toward Elk, Cervus Elaphus, And Wolves, Canis Lupus, L. David Mech, Rick T. Mcintyre, Douglas W. Smith Jan 2004

Unusual Behavior By Bison, Bison Bison, Toward Elk, Cervus Elaphus, And Wolves, Canis Lupus, L. David Mech, Rick T. Mcintyre, Douglas W. Smith

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

Incidents are described of Bison (Bison bison) in Yellowstone National Park mauling and possibly killing a young Elk (Cervus elaphus) calf, chasing wolves (Canis lupus) off Elk they had just killed or were killing, and keeping the wolves away for extended periods. During one of the latter cases, the Bison knocked a wolf-wounded Elk down. Bison were also seen approaching wolves that were resting and sleeping, rousting them, following them to new resting places and repeating this behavior. These behaviors might represent some type of generalized hyper-defensiveness that functions as an anti-predator strategy.


Record High Wolf, Canis Lupus, Pack Density, L. David Mech, Shawn Tracy Jan 2004

Record High Wolf, Canis Lupus, Pack Density, L. David Mech, Shawn Tracy

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

This report documents a year-around Wolf (Canis lupus) density of 18.2/100 km2 and a summer density of 30.8/100 km2, in a northeastern Minnesota Wolf pack. The previous record was a summer density of 14.1/100 km2, for a Wolf pack on Vancouver Island, British Columbia, Canada.


Feeding Responses Of Juvenile And Adult Streblospio Benedicti Webster (Spionidae) To Organic Chemicals Bound To Glass Microbeads, Heidi Kathryn Mahon Oct 2003

Feeding Responses Of Juvenile And Adult Streblospio Benedicti Webster (Spionidae) To Organic Chemicals Bound To Glass Microbeads, Heidi Kathryn Mahon

Biological Sciences Theses & Dissertations

Spionid polychaetes feed at the sediment-water interface using a pair of ciliated palps. Polychaetes select food particles based upon characteristics including size, texture, specific gravity and organic coatings. Juvenile and adult spionids have different stable isotopic carbon signals, indicating the potential to differentiate organic cues ontogenetically. In the present study, the feeding responses of juvenile and adult Streblospio benedicti Webster to seven organic coatings bound (five amino acids and two carbohydrates) to glass microbeads were tested. Juveniles and adults were highly selective for all seven types of organically coated beads. Juveniles were highly selective for threonine; whereas adults were highly …


An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne H. Alonzo, Paul Switzer, Marc Mangel Jan 2003

An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne H. Alonzo, Paul Switzer, Marc Mangel

Faculty Research & Creative Activity

Summary 1. Changes in species' abundance and distributions caused by human disturbances can have indirect effects on other species in a community. Although ecosystem approaches to management are becoming increasingly prevalent, they require a fuller understand- ing of how individual behaviour determines interactions within and between species. 2. Ecological interactions involving krill are of major importance to many species within the Antarctic. Despite extensive knowledge of the ecosystem that they occupy, there is still incomplete understanding of the links between species and the effect of environmental conditions on these interactions. In this study, we extended a behavioural model used previously …


Effects Of Experience And Body Size On Refuge Choice In The Crayfish Orconectes Immunis, Patrick S. Forsythe, Deborah S. Wyatt, Paul V. Switzer Jan 2003

Effects Of Experience And Body Size On Refuge Choice In The Crayfish Orconectes Immunis, Patrick S. Forsythe, Deborah S. Wyatt, Paul V. Switzer

Faculty Research & Creative Activity

We investigated whether refuge size or experience with a refuge affected the refuge use of male Orconectes immunis crayfish. Individuals were given choices among seven refuges for 10 consecutive days. Refuges were formed from equal length but different diameter PVC pipe and placed in an array in a random sequence. Three treatments were used. In the Novel Refuge treatment, individuals were placed in a new test arena with a new arrangement of cleaned refuges every day. In the Nonremoval treatment, individuals were left in the same arena with the same set of refuges each day. In the Removal treatment, individuals …


Restoration Of The Red Wolf, Michael K. Phillips, V. Gary Henry, Brian T. Kelly Jan 2003

Restoration Of The Red Wolf, Michael K. Phillips, V. Gary Henry, Brian T. Kelly

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

"WOLFERS" IN NORTHEASTERN North Carolina were busy on February 5, 1768. Records from the Tyrrell County courthouse read:

Giles Long and Thomas Wilkinson awarded one pound for a certified wolf scalp; Jeremiah Norman awarded two pounds for certified wolf and wild-cat scalps; Davenport Smithwick awarded one pound for a certified wolf-scalp.

Such was the nature of the war on the wolf: people killed them for money. The belief of the time held that the war was necessary because it was humankind's manifest destiny to tame the wilderness. And for the wilderness to be tame, the wolf had to be exterminated. …


Wolf-Prey Relations, L. David Mech, Rolf O. Peterson Jan 2003

Wolf-Prey Relations, L. David Mech, Rolf O. Peterson

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

AS 1 (L. o. MECH) watched from a small ski plane while fifteen wolves surrounded a moose on snowy Isle Royale, I had no idea this encounter would typify observations I would make during 40 more years of studying wolf-prey interactions.

My usual routine while observing wolves hunting was to have my pilot keep circling broadly over the scene so I could watch the wolves' attacks without disturbing any of the animals. Only this time there was no attack. The moose held the wolves at bay for about 5 minutes (fig. p), and then the pack left.

From this observation …


Ecological Games In Space And Time: The Distribution And Abundance Of Antarctic Krill And Penguins, Suzanne Alonzo, Paul Switzer, Marc Mangel Jan 2003

Ecological Games In Space And Time: The Distribution And Abundance Of Antarctic Krill And Penguins, Suzanne Alonzo, Paul Switzer, Marc Mangel

Faculty Research & Creative Activity

The distribution and abundance of organisms are affected by behaviors, such as habitat selection, foraging, and reproduction. These behaviors are driven by interactions within and between species, environmental conditions, and the biology of the species in-volved. Although extensive theoretical work has explored predator–prey dynamics, these models have not considered the impact of behavioral plasticity and life-history trade-offs on predicted patterns. We apply a modeling method that allows the consideration of a spatial, dynamic ecological game between predators and prey using a life-history perspec-tive. As an illustrative example, we model the habitat selection of Antarctic krill and penguins during the time …


Ecological Games In Space And Time: The Distribution And Abundance Of Antarctic Krill And Penguins, Suzanne H. Alonzo, Paul V. Switzer, Marc Mangel Jan 2003

Ecological Games In Space And Time: The Distribution And Abundance Of Antarctic Krill And Penguins, Suzanne H. Alonzo, Paul V. Switzer, Marc Mangel

Faculty Research & Creative Activity

The distribution and abundance of organisms are affected by behaviors, such as habitat selection, foraging, and reproduction. These behaviors are driven by interactions within and between species, environmental conditions, and the biology of the species in-volved. Although extensive theoretical work has explored predator–prey dynamics, these models have not considered the impact of behavioral plasticity and life-history trade-offs on predicted patterns. We apply a modeling method that allows the consideration of a spatial, dynamic ecological game between predators and prey using a life-history perspec-tive. As an illustrative example, we model the habitat selection of Antarctic krill and penguins during the time …


An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne Alonzo, Paul Switzer, Marc Mangel Jan 2003

An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne Alonzo, Paul Switzer, Marc Mangel

Faculty Research & Creative Activity

Summary 1. Changes in species' abundance and distributions caused by human disturbances can have indirect effects on other species in a community. Although ecosystem approaches to management are becoming increasingly prevalent, they require a fuller understand- ing of how individual behaviour determines interactions within and between species. 2. Ecological interactions involving krill are of major importance to many species within the Antarctic. Despite extensive knowledge of the ecosystem that they occupy, there is still incomplete understanding of the links between species and the effect of environmental conditions on these interactions. In this study, we extended a behavioural model used previously …


Effects Of Experience And Body Size On Refuge Choice In The Crayfish Orconectes Immunis, Patrick Forsythe, Deborah Wyatt, Paul Switzer Jan 2003

Effects Of Experience And Body Size On Refuge Choice In The Crayfish Orconectes Immunis, Patrick Forsythe, Deborah Wyatt, Paul Switzer

Faculty Research & Creative Activity

We investigated whether refuge size or experience with a refuge affected the refuge use of male Orconectes immunis crayfish. Individuals were given choices among seven refuges for 10 consecutive days. Refuges were formed from equal length but different diameter PVC pipe and placed in an array in a random sequence. Three treatments were used. In the Novel Refuge treatment, individuals were placed in a new test arena with a new arrangement of cleaned refuges every day. In the Nonremoval treatment, individuals were left in the same arena with the same set of refuges each day. In the Removal treatment, individuals …


Wolves And Humans, Steven H. Fritts, Robert O. Stephenson, Robert D. Hayes, Luigi Boitani Jan 2003

Wolves And Humans, Steven H. Fritts, Robert O. Stephenson, Robert D. Hayes, Luigi Boitani

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

TRY TO IMAGINE a small group of wolves sitting at a table engaged in vigorous debate. These wolves are from various parts of the globe and are perhaps a bit more scholarly than most. In fact, they are especially knowledgeable about the biology of that notorious two-legged species, Homo sapiens. They have been brought together to document their relationship with humans over the last several millennia. Pause for a few moments and consider what they might say ...

Perhaps the wolves' discussion would chronicle the evils of the human species, including details of atrocities committed against lupine ancestors down …


Wolves: Behavior, Ecology, And Conservation: Photo Section I, Douglas W. Smith, Rolf Peterson, L. David Mech, Barron Crawford Jan 2003

Wolves: Behavior, Ecology, And Conservation: Photo Section I, Douglas W. Smith, Rolf Peterson, L. David Mech, Barron Crawford

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

Wolves in Yellowstone National Park's restored population often must compete with grizzly bears at the carcasses of their kills. Especially after their first feeding at a kill, wolves tend to relinquish their kills to bears. Photograph by Doug Smith.

Elk are one of the most common prey of wolves in the northern Rocky Mountains of North America, primarily because in most areas they tend to outnumber other prey. This large bull standing his ground escaped this pack. Photograph by Doug Smith.


Introduction, L. David Mech, Luigi Boitani Jan 2003

Introduction, L. David Mech, Luigi Boitani

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

THE WOLF IS TRULY a special animal. As the most widely distributed of all land mammals, the wolf, formally the gray wolf (Canis lupus), is also one of the most adaptable. It inhabits all the vegetation types of the Northern Hemisphere and preys on all the large mammals living there. It also feeds on all the other animals in its environment, scavenges, and can even eat fruits and berries. Wolves frequent forests and prairies, tundra, barren ground, mountains, deserts, and swamps. Some wolves even visit large cities, and, of course, the wolf's domesticated version, the dog, thrives in …


Wolf Social Ecology, L. David Mech, Luigi Boitani Jan 2003

Wolf Social Ecology, L. David Mech, Luigi Boitani

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

THE FIRST REAL BEGINNING to our understanding of wolf social ecology came from wolf 2204 on 23 May 1972. State depredation control trapper Lawrence Waino, of Duluth, Minnesota, had caught this female wolf 112 km ( 67 mi) south of where L. D. Mech had radio-collared her in the Superior National Forest 2 years earlier. A young lone wolf, nomadic over 100 km2 (40 mi2) during the 9 months Mech had been able to keep track of her, she had then disappeared until Waino caught her. From her nipples it was apparent that she had just been …


References, L. David Mech, Luigi Boitani Jan 2003

References, L. David Mech, Luigi Boitani

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

Abrams, P. A. 2000. The evolution of predator-prey interactions. Annu. Rev. Ecol. Syst. 31:79-105.

Abuladze, K. I. 1964. Osnovy Tsestodologii. Vol. IV. Teniatylentochnye gel' minty zhivotnykh i cheloveka i vyzyvaevaniia. Nauka, Moscow. 530 pp.

Achuff, P. L., and R. Petocz. 1988. Preliminary resource inventory of the Arjin Mountains Nature Reserve, Xinjiang, People's Republic of China. World Wide Fund for Nature, Gland, Switzerland. 78 pp.

Ackerman, B. B., F. A. Leban, M. D. Samuel, and E. 0. Garton. 1990. User's manual for program Home Range. 2d ed. Technical Report no. 15. Forestry, Wildlife, and Range Experiment Station, University ofldaho, Moscow.

Acorn, …


Wolf Population Dynamics, Todd K. Fuller, L. David Mech, Jean Fitts Cochrane Jan 2003

Wolf Population Dynamics, Todd K. Fuller, L. David Mech, Jean Fitts Cochrane

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

A LARGE, DARK WOLF poked his nose out of the pines in Yellowstone National Park as he thrust a broad foot deep into the snow and plowed ahead. Soon a second animal appeared, then another, and a fourth. A few minutes later, a pack of thirteen lanky wolves had filed out of the pines and onto the open hillside.

Wolf packs are the main social units of a wolf population. As numbers of wolves in packs change, so too, then, does the wolf population (Rausch 1967). Trying to understand the factors and mechanisms that affect these changes is what the …


Wolves: Behavior, Ecology, And Conservation: Photo Section Ii, Douglas W. Smith, L. David Mech, Isaac Babcock, Melissa Mccaw Jan 2003

Wolves: Behavior, Ecology, And Conservation: Photo Section Ii, Douglas W. Smith, L. David Mech, Isaac Babcock, Melissa Mccaw

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

Adult wolves are very attentive to the pups. Both parents feed and care for them. Any older siblings similarly participate in pup care and feeding. Kin selection is probably the best explanation for the latter behavior. Top: Photograph by Isaac Babcock. Bottom: Photograph by L. David Mech.