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Terpenes And Carbohydrate Source Influence Rumen Fermentation, Digestibility, Intake, And Preference In Sheep, J. J. Villalba, F. D. Provenza, K. C. Olson Jan 2006

Terpenes And Carbohydrate Source Influence Rumen Fermentation, Digestibility, Intake, And Preference In Sheep, J. J. Villalba, F. D. Provenza, K. C. Olson

Green Canyon Environmental Research Area, Logan Utah

We hypothesized that toxins and nutrients in foods interact to influence foraging behavior by herbivores. Based on this hypothesis we predicted that 1) terpenes in big sagebrush (Artemisia tridentata) influence intake and preference in sheep for diets varying in sources of nonstructural (barley grain) and structural (sugar beet pulp) carbohydrates, and 2) these effects are due to the differential effects of terpenes on fermentation products and apparent digestibility of each class of carbohydrates. Lambs were fed 2 isoenergetic and isonitrogenous diets with varying proportions of the same ingredients (beet pulp- and barley grain-based diet) or offered a choice between the …


Revegetation Of Reconstructed Reaches Of The Provo River, Heber Valley, Utah, John A. Rice Jan 2006

Revegetation Of Reconstructed Reaches Of The Provo River, Heber Valley, Utah, John A. Rice

All U.S. Government Documents (Utah Regional Depository)

Prior to the 1950s, the middle Provo River in Utah offered outstanding fish and wildlife habitat. This was due in part to the Provo River freely meandering through the Heber Valley. These bends in the river provided deep holes for fish and a dense streamside forest for many species of birds. This productive habitat was altered in the 1940s and 1950s when the river was dammed, channelized, and forced between dikes (figure 1). These dikes were constructed by the USDI Bureau of Reclamation (USBR) to contain high flows that came from additional water added to the Provo River from transbasin …


Integrated Restoration Strategies Towards Weed Control On Western Rangelands, U.S. Forest Service Jan 2006

Integrated Restoration Strategies Towards Weed Control On Western Rangelands, U.S. Forest Service

Wildlife Conservation and Management

An attempt to find native plant materials competitive with cheatgrass to help break the cheatgrass-fire cycle and begin the transition from exotic annual-dominated vegetation to native perennial dominated vegetation.


Fisheries Research Report No 154 - The Development Of A Rigorous Sampling Methodology For A Long-Term Annual Index Of Recruitment For Finfish Species From South-Western Australia., Daniel J. Gaughan, Suzanne G. Ayvazian, G Nowara, M Craine Jan 2006

Fisheries Research Report No 154 - The Development Of A Rigorous Sampling Methodology For A Long-Term Annual Index Of Recruitment For Finfish Species From South-Western Australia., Daniel J. Gaughan, Suzanne G. Ayvazian, G Nowara, M Craine

Fisheries Research Reports

Final FRDC Report - 1999/153.

This study has determined the optimal strategies to achieve statistically robust indices of recruitment of five key finfish species in south-western Australia. For another two species such indices could not be established. The sampling strategies developed will initially focus on the most appropriate location, month, and lunar phase, after which fine tuning of the sampling activity will be undertaken with respect to time of day, tide height, weather conditions etc. A significant outcome from the project is that five finfish species have a sampling strategy for recruits that can be utilized as a monitoring program …


Recommended Management Arrangements For The West Coast Commercial 'Wetline' Fishery. A Report To The Minister For Fisheries., West Coast And Gascoyne Management Planning Panel. Jan 2006

Recommended Management Arrangements For The West Coast Commercial 'Wetline' Fishery. A Report To The Minister For Fisheries., West Coast And Gascoyne Management Planning Panel.

Fisheries Management Papers

No abstract provided.


Recommended Access And Allocation Criteria For The West Coast And Gascoyne Commercial 'Wetline' Fisheries. A Report To The Ministry Of Fisheries., The Commercial Access Panel. Jan 2006

Recommended Access And Allocation Criteria For The West Coast And Gascoyne Commercial 'Wetline' Fisheries. A Report To The Ministry Of Fisheries., The Commercial Access Panel.

Fisheries Management Papers

The CAP’s primary responsibility was to develop criteria for access and allocation within the context of the management framework developed by the MPP. It is therefore important that this management paper is read in conjunction with the papers prepared by the MPP that outline the recommended management arrangements for the Gascoyne (Fisheries Management Paper No. 205) and the West Coast (Fisheries Management Paper No. 206) regions.


Assessment Of Western Rock Lobster Strategic Management Options. An Overview Of Bio-Economic, Sociological And Comparative Analysis. Vol. 1., Department Of Fisheries. Jan 2006

Assessment Of Western Rock Lobster Strategic Management Options. An Overview Of Bio-Economic, Sociological And Comparative Analysis. Vol. 1., Department Of Fisheries.

Fisheries Management Papers

The purpose of this review paper is to present the options for managing the fishery and to compare the current fishing effort control system to a more flexible one and to two types of individually transferable quota (ITQ) management systems, one with the current effort controls and the other without or with reduced1 effort controls.


Assessment Of Western Rock Lobster Strategic Management Options. A Bio-Economic Evaluation Of Management Options For The West Coast Rock Lobster Fishery. Vol. 2, Economic Research Associates Pty Ltd Jan 2006

Assessment Of Western Rock Lobster Strategic Management Options. A Bio-Economic Evaluation Of Management Options For The West Coast Rock Lobster Fishery. Vol. 2, Economic Research Associates Pty Ltd

Fisheries Management Papers

Economic Research Associates (ERA) was commissioned to evaluate the relative ‘socio-economic’ benefits of alternative management Scenarios for the Western Rock Lobster Managed Fishery. This study is intended as input into industry’s consideration of the future management policy direction for the fishery.


Assessment Of Western Rock Lobster Strategic Management Options. How Do Quota Management Systems Work In Rock Lobster Fisheries? Vol. 4, Tim Bray, Steven Gill, Ron Edwards Jan 2006

Assessment Of Western Rock Lobster Strategic Management Options. How Do Quota Management Systems Work In Rock Lobster Fisheries? Vol. 4, Tim Bray, Steven Gill, Ron Edwards

Fisheries Management Papers

Quota management systems are now in place for the New Zealand, Tasmanian and South Australian rock lobster fisheries. New Zealand was the first to move to QMS (1989), followed by the Southern Zone of South Australia (1993), Tasmania (1998) and Northern Zone South Australia (2001). As part of a review of the system of management used for the West Coast Rock Lobster Fishery, a West Australian delegation visited New Zealand, Tasmania and South Australia in 2004 to learn more about the management systems in place for their respective rock lobster fisheries.


Science-Based Organic Farming 2006: Toward Local And Secure Food Systems, Charles A. Francis, Katja Koehler-Cole, Twyla Hansen, Peter Skelton Jan 2006

Science-Based Organic Farming 2006: Toward Local And Secure Food Systems, Charles A. Francis, Katja Koehler-Cole, Twyla Hansen, Peter Skelton

Publications from the Center for Applied Rural Innovation (CARI)

Organic farming includes growing food and fiber—animals, agronomic crops, horticultural fruits and vegetables, related products—as one dynamic and rapidly evolving component of our complex U.S. food system. Even as more farmers are moving toward organic certification and participation in an environmentally sound and economically lucrative market, questions arise about the long-term social impacts and sustainability of a set of practices that has gone from a movement to an industry. Consolidations in the organic trade have brought multinational corporations to the table, as they have observed a grassroots activity that has grown by 20% per year for the past two decades, …


Scientific Reports Of Soviet Whaling Expeditions In The North Pacific, 1955-1978, Yulia V. Ivashchenko, Phillip J. Clapham, Robert L. Brownell Jr. Jan 2006

Scientific Reports Of Soviet Whaling Expeditions In The North Pacific, 1955-1978, Yulia V. Ivashchenko, Phillip J. Clapham, Robert L. Brownell Jr.

United States Department of Commerce: Staff Publications

The translated and annotated materials in this volume constitute a collection of 18 formerly secret internal reports written by Soviet scientists working aboard whaling factory ships in the North Pacific. The reports cover the period from 1955 to 1978. During most of this time, the USSR was engaged in a massive campaign of illegal whaling worldwide; these illegal catches continued until introduction of the International Whaling Commission’s International Observer Scheme in 1972. The reports were copied from the archives of the Pacific Research and Fisheries Center (TINRO) in Vladivostok by Alfred A. Berzin, the former director of TINRO’s marine mammal …


Differential Expression Of Immune Response Genes In Steller Sea Lions (Eumetopias Jubatus): An Indicator Of Ecosystem Health?, Lizabeth Bowen, Brian Aldridge, Kimberlee Beckmen, Tom Gelatt, Lorrie Rea, Kathy Burek, Ken Pitcher, Jeffrey L. Stott Jan 2006

Differential Expression Of Immune Response Genes In Steller Sea Lions (Eumetopias Jubatus): An Indicator Of Ecosystem Health?, Lizabeth Bowen, Brian Aldridge, Kimberlee Beckmen, Tom Gelatt, Lorrie Rea, Kathy Burek, Ken Pitcher, Jeffrey L. Stott

United States Department of Commerce: Staff Publications

Characterization of the polygenic and polymorphic features of the Steller sea lion major histocompatibility complex (MHC) provides an ideal window for evaluating immunologic vigor of the population and identifying emergence of new genotypes that reflect ecosystem pressures. MHC genotyping can be used to measure the potential immunologic vigor of a population. However, since ecosystem-induced changes to MHC genotype can be slow to emerge, measurement of differential expression of these genes can potentially provide real-time evidence of immunologic perturbations. MHC DRB genes were cloned and sequenced using peripheral blood mononuclear leukocytes derived from 10 Steller sea lions from southeast Alaska, Prince …


Relating Chronic Toxicity Responses To Population-Level Effects: A Comparison Of Population-Level Parameters For Three Salmon Species As A Function Of Low-Level Toxicity, Julann A. Spromberg, James P. Meador Jan 2006

Relating Chronic Toxicity Responses To Population-Level Effects: A Comparison Of Population-Level Parameters For Three Salmon Species As A Function Of Low-Level Toxicity, Julann A. Spromberg, James P. Meador

United States Department of Commerce: Staff Publications

Standard laboratory toxicity tests assess the physiological responses of individual organisms to exposure to toxic substances under controlled conditions. Time and space restrictions often prevent the assessment of population-level responses to a toxic substance. Contaminants can affect various biological functions (e.g. growth, fecundity or behavior), which may alter different demographic traits, leading to population-level impacts. In this study,immune suppression, reproductive dysfunction and somatic growth impairment were examined using life history matrix models for coho salmon (Oncorhynchus kisutch), sockeye salmon (Oncorhynchus nerka) and chinook salmon (Oncorhynchus tshawytscha). Our intent was to gauge the relative magnitude …


Studies Of Beaked Whale Diving Behavior And Odontocete Stock Structure In Hawai‘I In March/April 2006, Robin W. Baird, Gregory S. Schorr, Daniel L. Webster, Daniel J. Mcsweeney, Sabre D. Mahaffy Jan 2006

Studies Of Beaked Whale Diving Behavior And Odontocete Stock Structure In Hawai‘I In March/April 2006, Robin W. Baird, Gregory S. Schorr, Daniel L. Webster, Daniel J. Mcsweeney, Sabre D. Mahaffy

United States Department of Commerce: Staff Publications

Small-boat surveys were undertaken in March/April 2006 off the west side of the island of Hawai‘i for the purposes of obtaining dive data from Blainville’s (Mesoplodon densirostris) and Cuvier’s (Ziphius cavirostris) beaked whales, as well as collecting biopsy samples and photo-identification of these and other species of odontocetes for studies of stock structure and residency patterns. There were 157 sightings of 13 species of odontocetes in 4,264 km of effort, with 120 genetic samples from seven species and over 29,000 photographs from 13 species obtained. Photographic matching to existing catalogs is currently underway for eight species. …


A Survey For Odontocete Cetaceans Off Kaua‘I And Ni‘Ihau, Hawai‘I, During October And November 2005: Evidence For Population Structure And Site Fidelity, Robin W. Baird, Gregory S. Schorr, Daniel L. Webster, Sabre D. Mahaffy, Anne B. Douglas, Antoinette M. Gorgone, Daniel J. Mcsweeney Jan 2006

A Survey For Odontocete Cetaceans Off Kaua‘I And Ni‘Ihau, Hawai‘I, During October And November 2005: Evidence For Population Structure And Site Fidelity, Robin W. Baird, Gregory S. Schorr, Daniel L. Webster, Sabre D. Mahaffy, Anne B. Douglas, Antoinette M. Gorgone, Daniel J. Mcsweeney

United States Department of Commerce: Staff Publications

Considerable uncertainty exists regarding population structure and population sizes of most species of odontocetes in the Hawaiian Islands. A small-boat based survey for odontocetes was undertaken off the islands of Kaua‘i and Ni‘ihau in October and November 2005 to photoidentify individuals and collect genetic samples for examining stock structure. Field effort on 24 days covered 2,194 km of trackline. Survey coverage was from shallow coastal waters out to over 3,000 m depth, though almost half (47%) was in waters less than 500 m in depth. There were 56 sightings of five species of odontocetes: spinner dolphins (30 sightings); bottlenose dolphins …


Lessons From Monitoring Trends In Abundance Of Marine Mammals, Barbara L. Taylor, Melissa Martinez, Tim Gerrodette, Jay Barlow, Yvana N. Hrovat Jan 2006

Lessons From Monitoring Trends In Abundance Of Marine Mammals, Barbara L. Taylor, Melissa Martinez, Tim Gerrodette, Jay Barlow, Yvana N. Hrovat

United States Department of Commerce: Staff Publications

We assessed scientists’ ability to detect declines of marine mammal stocks based on recent levels of survey effort, when the actual decline is precipitous. We defined a precipitous decline as a 50% decrease in abundance in 15 yr, at which point a stock could be legally classified as “depleted” under the U.S. Marine Mammal Protection Act.We assessed stocks for three categories of cetaceans: large whales (n = 23, most of which are listed as endangered), beaked whales (n = 11, potentially vulnerable to anthropogenic noise), and small whales/dolphins/porpoises (n = 69, bycatch in fisheries and important abundant …


Taxonomic Considerations In Listing Subspecies Under The U.S. Endangered Species Act, Susan M. Haig, Erik A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie M. Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Pete Loschl, Thomas D. Mullins, Lisa M. Sheffield Jan 2006

Taxonomic Considerations In Listing Subspecies Under The U.S. Endangered Species Act, Susan M. Haig, Erik A. Beever, Steven M. Chambers, Hope M. Draheim, Bruce D. Dugger, Susie M. Dunham, Elise Elliott-Smith, Joseph B. Fontaine, Dylan C. Kesler, Brian J. Knaus, Iara F. Lopes, Pete Loschl, Thomas D. Mullins, Lisa M. Sheffield

United States Geological Survey: Staff Publications

The U.S. Endangered Species Act (ESA) allows listing of subspecies and other groupings below the rank of species. This provides the U.S. Fish and Wildlife Service and the National Marine Fisheries Service with a means to target the most critical unit in need of conservation. Although roughly one-quarter of listed taxa are subspecies, these management agencies are hindered by uncertainties about taxonomic standards during listing or delisting activities. In a review of taxonomic publications and societies, we found few subspecies lists and none that stated standardized criteria for determining subspecific taxa. Lack of criteria is attributed to a centuries-old debate …


Conserving Biodiversity In Human-Dominated Landscapes, Dale D. Goble, J. Michael Scott, Frank W. Davis Jan 2006

Conserving Biodiversity In Human-Dominated Landscapes, Dale D. Goble, J. Michael Scott, Frank W. Davis

United States Geological Survey: Staff Publications

The two volumes of The Endangered Species Act at Thirty look backward to evaluate the effectiveness of the act over its first three decades (Wilcove and McMillan 2006; Scott et al. 2006, chap. 2; Goble, this volume; Svancara, this volume; Callicott, this volume; Norton, this volume) and also forward to suggest how it can be used as a cornerstone for conserving biological diversity in increasingly human-dominated landscapes (Davis et al. 2006; Bean 2006). The chapters in part 2 of this volume, for example, appraise the science of the 1990s and 2000s at both the large scale (Lomolino, this volume; Naeem …


Endangered Species Time Line, Leona K. Svancara, J. Michael Scott, Dale D. Goble, Frank W. Davis, Donna Brewer Jan 2006

Endangered Species Time Line, Leona K. Svancara, J. Michael Scott, Dale D. Goble, Frank W. Davis, Donna Brewer

United States Geological Survey: Staff Publications

The Endangered Species Act (ESA) is embedded in a web of statutes designed to regulate relationships between humans and other species that stretch back nearly a millennium (Goble, this volume; Goble and Freyfogle 2002). This chapter presents a time line of federal actions taken to protect wildlife beginning with passage of the Land and Water Conservation Fund Act in 1963 (Act of May 28, 1963). Earlier laws to protect wildlife are discussed elsewhere (Goble, this volume). The time line emphasizes federal actions that conserve species at risk of extinction and significant events in the course of implementing the Endangered Species …


Isotope Sourcing Of Prehistoric Willow And Tule Textiles Recovered From Western Great Basin Rock Shelters And Caves: Proof Of Concept, Larry V. Benson, E. M. Hattori, H. E. Taylor, S. R. Poulson, E. A. Jolie Jan 2006

Isotope Sourcing Of Prehistoric Willow And Tule Textiles Recovered From Western Great Basin Rock Shelters And Caves: Proof Of Concept, Larry V. Benson, E. M. Hattori, H. E. Taylor, S. R. Poulson, E. A. Jolie

United States Geological Survey: Staff Publications

Isotope and trace-metal analyses were used to determine the origin of plants used to manufacture prehistoric textiles (basketry and matting) from archaeological sites in the western Great Basin. Research focused on strontium (87Sr/86Sr) and oxygen (18O/16O) isotope ratios of willow (Salix sp.) and tule (Schoenoplectus sp.), the dominant raw materials in Great Basin textiles. The oxygen-isotope data indicated that the willow and tule used to produce the textiles were harvested from the banks of rivers or in marshes characterized by flowing water and not from lakes or sinks. The strontium-isotope …


The Agricultural Productivity Of Chaco Canyon And The Source(S) Of Pre-Hispanic Maize Found In Pueblo Bonito, Larry Benson, John Stein, Howard Taylor, Richard Friedman, Thomas C. Windes Jan 2006

The Agricultural Productivity Of Chaco Canyon And The Source(S) Of Pre-Hispanic Maize Found In Pueblo Bonito, Larry Benson, John Stein, Howard Taylor, Richard Friedman, Thomas C. Windes

United States Geological Survey: Staff Publications

Agricultural productivity estimates suggest that the core area of Chaco Canyon could have sustained only a few hundred individuals. Modern analogues of existing Pueblo populations and their domestic habitations with Chaco structures suggest that Chaco at times had a resident population exceeding 2000 people. These data suggest that maize would have had to be imported to feed permanent residents and those visiting Chaco during ritual–political gatherings and those who participated in the accelerated construction and modification of great houses between AD 1030 and 1130. Comparison of strontium-isotope and trace-element ratios of synthetic soil and natural waters from sites within the …


A Comparison Of Presettlement Vegetation And Fire Regimes With Current Patterns In Oak Woodlands And Shrublands Of Sw Oregon, Patricia S. Muir Dr., Paul Hosten Dr. Jan 2006

A Comparison Of Presettlement Vegetation And Fire Regimes With Current Patterns In Oak Woodlands And Shrublands Of Sw Oregon, Patricia S. Muir Dr., Paul Hosten Dr.

Joint Fire Science Program Research Project Reports

Fuel reduction efforts on BLM lands in southwestern Oregon are motivated by the need to reduce fire hazard and restore and rehabilitate ecosystems. Successful ecosystem restoration depends, in part, on understanding the target: what ecosystem model is considered natural and healthy for a given area? Oak (Quercus garryana) woodlands and shrublands are two of the most characteristic ecosystems in interior valleys of southwest Oregon, and extensive acreages within these systems are treated annually for fuel reduction. However, these are also two of the least understood ecosystems in the region. We know little about their presettlement attributes, responses to disturbance, or …


An Internet Based Portal For Fire Science And Management In The Southern Region Jan 2006

An Internet Based Portal For Fire Science And Management In The Southern Region

Joint Fire Science Program Research Project Reports

Task 1 – Organize a technical advisory team and host an initial workshop to explore methods for integrating FRAMES, TTRS, and ESFS websites.

Task 2 – Identify and acquire data, tools, and publications from funded JFSP and NFP projects working with the JFSP and NFP project databases and principal investigators. Also, when possible identify and acquire data and tools used and created by others in the wildland fire community including state agencies, educational institutions, and non-governmental organizations.

Task 3 – Develop and post online FGDC metadata records for all datasets from funded JFSP and NFP projects as well as key …


Natural Resource Management Issues In The Avon River Basin, Paul Galloway Jan 2006

Natural Resource Management Issues In The Avon River Basin, Paul Galloway

Resource management technical reports

Analyses the risk of soil, land and water degradation within the Avon River Basin of Western Australia. Information is based on the interpretation of the characteristics of soils and landscapes within the Avon River basin. This report deals with 15 natural resource management issues and describes the extent of each issue, the impacts that each issue will have, management options that can be used to deal with each issue, and the effectiveness of each management option in dealing with the issues.


Asian Carp -Aquatic Invasive Species Issues, Program Accomplishments, And Program Needs Jan 2006

Asian Carp -Aquatic Invasive Species Issues, Program Accomplishments, And Program Needs

National Invasive Species Council

Pathways and Introductions into the United States

Biology and Ecology

Distribution and Abundance

Ecological Risks and Impacts

Threats to the Great Lakes Basin

Threat to Other Basins and Locations

What is the Fish and Wildlife Service Doing?


When Landscaping Goes Bad: The Incipient Invasion Of Mahonia Bealei In The Southeastern United States, Craig R. Allen, Ahjond S. Garmestani, Jill A. Labram, Amanda E. Peck, Luanna B. Prevost Jan 2006

When Landscaping Goes Bad: The Incipient Invasion Of Mahonia Bealei In The Southeastern United States, Craig R. Allen, Ahjond S. Garmestani, Jill A. Labram, Amanda E. Peck, Luanna B. Prevost

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Woodlots are forest islands embedded within an urban matrix, and often represent the only natural areas remaining in suburban areas. Woodlots represent critical conservation areas for native plants, and are important habitat for wildlife in urban areas. Invasion by non-indigenous (NIS) plants can alter ecological structure and function, and may be especially severe in remnant forests where NIS propagule pressure is high. Woody shrubs in the Family Berberidaceae have been well documented as invaders of the forest–urban matrix in North America. Mahonia bealei (Berberidaceae) is a clonal shrub native to China, and is a popular ornamental in the Southeastern United …


Predictors Of Introduction Success In The South Florida Avifauna, Craig R. Allen Jan 2006

Predictors Of Introduction Success In The South Florida Avifauna, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Biological invasions are an increasing global challenge, for which single-species studies and analyses focused on testing single hypotheses of causation in isolation are unlikely to provide much additional insight. Species interact with other species to create communities, which derive from species interactions and from the interactions of species with the scale specific elements of the landscape that provide suitable habitat and exploitable resources. I used logistic regression analysis to sort among potential intrinsic, community and landscape variables that theoretically influence introduction success. I utilized the avian fauna of the Everglades of South Florida, and the variables body mass, distance to …


Life-History And Ecological Correlates Of Geographic Variation In Egg And Clutch Mass Among Passerine Species, Thomas E. Martin, R. D. Bassar, S. K. Bassar, J. J. Fontaine, P. Lloyd, H. A. Mathewson, A. M. Niklison, A. Chalfoun Jan 2006

Life-History And Ecological Correlates Of Geographic Variation In Egg And Clutch Mass Among Passerine Species, Thomas E. Martin, R. D. Bassar, S. K. Bassar, J. J. Fontaine, P. Lloyd, H. A. Mathewson, A. M. Niklison, A. Chalfoun

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Broad geographic patterns in egg and clutch mass are poorly described, and potential causes of variation remain largely unexamined. We describe interspecific variation in avian egg and clutch mass within and among diverse geographic regions and explore hypotheses related to allometry, clutch size, nest predation, adult mortality, and parental care as correlates and possible explanations of variation. We studied 74 species of Passeriformes at four latitudes on three continents: the north temperate United States, tropical Venezuela, subtropical Argentina, and south temperate South Africa. Egg and clutch mass increased with adult body mass in all locations, but differed among locations for …


Status Of The Northern River Otter In Nebraska, Richard Bischof Jan 2006

Status Of The Northern River Otter In Nebraska, Richard Bischof

Nebraska Game and Parks Commission: Staff Research Publications

Historically, the northern river otter (Lontra canadensis) was well established throughout Nebraska (Swenk 1908) and was especially abundant along the Missouri and the Platte rivers (Jones 1964). Unregulated trapping and habitat degradation caused declines throughout most of the northern river otter's historic range (Nilsson 1980, Melquist and Dronkert 1987), including Nebraska. The species was considered extirpated in Nebraska by the early 1900s.


Refuge Update – January/February 2006, Volume 3, Number 1 Jan 2006

Refuge Update – January/February 2006, Volume 3, Number 1

RefugeUpdate (USFWS-NWRS)

Table of Contents:

Three New Species in Alaska
Conserving Wildlife State by State
Focus on…Incident Command
Mushing to Your New Job