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Full-Text Articles in Population Biology

First Records And First Proven Breeding Of Lesser Grey Shrike, Lanius Minor, In Mongolia, Markus Deutsch, Axel Bräunlich Jan 2007

First Records And First Proven Breeding Of Lesser Grey Shrike, Lanius Minor, In Mongolia, Markus Deutsch, Axel Bräunlich

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

During a trip to the Dzungarian Gobi in southwestern Mongolia, a group of German birdwatchers found several territorial lesser grey shrikes, Lanius minor, and documented an active nest. The species had not previously been recorded from Mongolia. Observations were made near Bulgan gol (Bulgan river; nest coordinates: 46°6’N 91°32’E, 1190 m a.s.l.) in Khovd aimag (Khovd province) on June 24, 2006. Besides two territorial pairs, of which a female could be photographically documented on the nest, at least four more territorial adults were found within an area of about 1.5 km2. Based on these records, an abundance …


Numbers, Distribution And Social Structure Of Kiang (Equus Kiang Moorcroft 1841) Population In The Southwestern Part Of Tibet, China, Natalia V. Paklina, Chris Van Orden Jan 2007

Numbers, Distribution And Social Structure Of Kiang (Equus Kiang Moorcroft 1841) Population In The Southwestern Part Of Tibet, China, Natalia V. Paklina, Chris Van Orden

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In September - October 1998 we made an extensive survey in southwest Tibet to study numbers, distribution and social structure of the kiang population in this remote part of its range. Kiangs were sighted between 29º 40’ and 32º 50’ N, and 81º- 86º E. They preferred broad flat valleys with lakes at an altitude from 4,000 up to 5,000 m. Small kiang groups and solitary animals were sighted in Transhimalaya. There were no kiangs in Tsangpo (Brahmaputra) River valley, in the sand desert near Ali and in the Clay Mountains near Tsada. Seven old kiang corpses were found along …


Some Information On The Ecology Of Khulan (Equus Hemionus Pallas, 1775) In The Western Part Of The South Gobi Province, Mongolia, D. Tsendjav, S. Purevsuren Jan 2007

Some Information On The Ecology Of Khulan (Equus Hemionus Pallas, 1775) In The Western Part Of The South Gobi Province, Mongolia, D. Tsendjav, S. Purevsuren

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

This short study provides information on the density and distribution of khulans in September 2003 and speculates about factors that negatively influence the khulan population in the sums of Khurmen, Bayandalai, Noyon, Sevrei, and Gurvantes in the South Gobi province.


Turkmenian Kulan (Equus Onager Kulan) Captive Population, Anna Mekarska Jan 2007

Turkmenian Kulan (Equus Onager Kulan) Captive Population, Anna Mekarska

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The Turkmenian kulan (Equus onager kulan) is critically endangered, fewer then 1,500 animals are left in the wild. In 2004, there were additional 570 Turkmenian kulans living in captivity: 156 specimens in Euro-Asian zoos, 83 in Askania Nova Reserve and 331 in Canyon Colorado Equid Sanctuary. Population size in EAZA region is decreasing both in terms of numbers and genetic parameters. Those facts underline the urgent need for coordinating development of Eurasian kulan’s captive population. From 2004 onwards, large efforts to create healthy breeding groups in zoos raised bigger interest in this species in European zoos.


Identification Of Herder-Wild Equid Conflicts In The Great Gobi B Strictly Protected Area In Sw Mongolia, Petra Kaczensky, N. Enkhsaihan, O. Ganbaatar, Christian Walzer Jan 2007

Identification Of Herder-Wild Equid Conflicts In The Great Gobi B Strictly Protected Area In Sw Mongolia, Petra Kaczensky, N. Enkhsaihan, O. Ganbaatar, Christian Walzer

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In protected areas of Mongolian overgrazing, competition with wild ungulates and poaching are important management concerns. The Great Gobi B Strictly Protected Area (SPA) in SW Mongolia is a re-introduction site for the Przewalski’s horse (Equus ferus przewalskii), a stronghold of the Asiatic wild ass (Equus hemionus), and remains an important grazing area for seminomadic herders. We show the power of simple inventory and monitoring methods to assess herder-wildlife conflicts, by combining data of: (1) human and livestock demographic data, (2) migration patterns, of semi-nomadic herders, (3) monthly surveys of wild- and domestic ungulates, and (4) …


Kiangs (Equus Kiang, Moorcroft 1841) In Sikkim, India, Natalia V. Paklina, Chris Van Orden Jan 2007

Kiangs (Equus Kiang, Moorcroft 1841) In Sikkim, India, Natalia V. Paklina, Chris Van Orden

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Between the 5th and 10th of March 2001 we completed a 450 km route by car in Northern Sikkim. During the trip along the southern slopes of the Himalayas and Sikkim Plateau we didn’t see a single kiang. According to the local people and military personnel in Sikkim, kiangs are known only in the outer limits of the Sikkim Plateau, where wild animals have a possibility to migrate free over the Chinese-Indian border. In winter only small groups of kiang incidentally come to the Sikkim Plateau from South Tibet. But in May more of them come there and …


Current Status Of The Khulan (Equus Hemionus) In The Trans-Altai Gobi, Enkhbileg Dulamtseren, Adiya Yadamjav, Dovchindorj Ganbold, Mijidorj Batmunkh Jan 2007

Current Status Of The Khulan (Equus Hemionus) In The Trans-Altai Gobi, Enkhbileg Dulamtseren, Adiya Yadamjav, Dovchindorj Ganbold, Mijidorj Batmunkh

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Since 1975, 25 wildlife surveys have been conducted in the Trans-Altai Gobi. In this paper we summarize results from the last 11 surveys, conducted between October 2000 and April 2005, and discuss our findings together with results from previous surveys.


Assessment Of Non-Metric Skull Characters And Age Determination In The Asiatic Wild Ass Equus Hemionus: A Methodological Approach, Hermann Ansorge, Annegret Stubbe, Nyamsuren Batsaikhan, Ravčigijn Samjaa, Michael Stubbe Jan 2007

Assessment Of Non-Metric Skull Characters And Age Determination In The Asiatic Wild Ass Equus Hemionus: A Methodological Approach, Hermann Ansorge, Annegret Stubbe, Nyamsuren Batsaikhan, Ravčigijn Samjaa, Michael Stubbe

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The report presents the first information on the use of non-metric skull characters and age determination by tooth section for Asiatic wild asses. It was initiated by a collection of more than 400 skulls of the Asiatic wild ass from the Bordzongijn-Gobi 2002-2004. The methodological overview gives a first research prospect in Asiatic Wild Ass concerning the use of non-metric skull characters as a morphological tool for assessing genetic variability, determining epigenetic divergences and evaluating fluctuating asymmetry. The time course of tooth eruption and replacement in the Asiatic wild ass is described with regard to its use for age determination. …


Semi-Wild Population Of Kulans In The Bukhara Breeding Centre And Their Co-Habitation With Przewalski’S Horses, Karim Bahloul, Olga B. Pereladova, Natalia V. Soldatova, Ekaterina V. Sidorenko, Antoine J. Sempere Jan 2007

Semi-Wild Population Of Kulans In The Bukhara Breeding Centre And Their Co-Habitation With Przewalski’S Horses, Karim Bahloul, Olga B. Pereladova, Natalia V. Soldatova, Ekaterina V. Sidorenko, Antoine J. Sempere

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Asiatic wild asses and Przewalski's horses initially inhabited steppe, semi-desert and desert areas, but Przewalski's horses became extinct in the wild, and kulans are under threat of disappearance. The Bukhara Breeding Centre (Uzbekistan) was created in 1976 for conservation and reintroduction of wild ungulate species. In 1977-1978, five kulans (two males and three females) from Barsa-Kelmes Island on the Aral lake were introduced to the reserve. The group increased to 25-30 animals in 1995-1998, when five Przewalski's horses from Moscow and St. Petersburg zoos were introduced to the same territory. We analyzed the home ranges, preferred habitats and social interactions …


Social Networks In Wild Asses: Comparing Patterns And Processes Among Populations, Daniel I. Rubenstein, Siva Sundaresan, Ilya Fischhoff, David Saltz Jan 2007

Social Networks In Wild Asses: Comparing Patterns And Processes Among Populations, Daniel I. Rubenstein, Siva Sundaresan, Ilya Fischhoff, David Saltz

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Asiatic wild asses inhabit some of the most arid environments in the world. All live in fissionfusion societies, but demography varies and the deserts in which they live often differ in subtle ways. Characterizing details of social structure of wild ass populations has been a challenge and has made it difficult to determine causes and consequences of any differences that might exist. We use network theory to compare the social structures of two populations of Asiatic asses/ onagers inhabiting the Negev desert, Israel and khur of the Little Rann of Kuch, India and show that populations differ in important structural …


Chlorophacinone Baiting For Belding’S Ground Squirrels, Craig A. Ramey, George H. Matschke, Richard M. Engeman Jan 2007

Chlorophacinone Baiting For Belding’S Ground Squirrels, Craig A. Ramey, George H. Matschke, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

The efficacy of using 0.01% chlorophacinone on steam-rolled oat (SRO) groats applied in CA alfalfa by spot-baiting/hand baiting around burrow entrances (~11.5 g) to control free-ranging Belding's ground squirrels (Spermophilus beldingi) were compared in 6 randomly assigned square treatment units (TUs). Four TUs were given the rodenticide and 2 treated with placebo bait. Each TU was a 0.4 ha square surrounded by a similarly treated 5.5 ha square buffer zone. Baits were applied on May 13 and re-applied, on May 20 and May 22, after 7 days of un-forecasted cool wet weather greatly reduced their above ground activity. Pesticide (EPA …


Inventory And Monitoring Of Aquatic Bird Species On Lakes Mead And Mohave 2004 - 2006, Joseph Barnes Sep 2006

Inventory And Monitoring Of Aquatic Bird Species On Lakes Mead And Mohave 2004 - 2006, Joseph Barnes

Wildlife Monitoring

This project was completed as part of a task agreements awarded by the National Park Service (NPS), Lake Mead National Recreation Area (LAME), to the Public Lands Institute (PLI) at the University of Nevada, Las Vegas (UNLV). This final report was completed under a task agreement ending on September 30, 2006, and was completed in support of an NPS project funded by the Southern Nevada Public Lands Management Act (PLMA) to inventory and monitor shoreline and near-shore natural resources on Lakes Mead and Mohave (DOI 2005). This report details inventory and monitoring efforts on shoreline and aquatic bird species between …


Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2005), Daniel M. Dauer Aug 2006

Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2005), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

Macrobenthic communities of the Elizabeth River watershed have been quantitatively sampled since summer 1999. This report presents the data from the seventh year of sampling in 2005. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of the tidal waters of the Elizabeth River watershed as indicated by the structure of the benthic communities. (2) To conduct trend analyses on long-term data at 14 fixed-point stations to relate temporal trends in the benthic communities to changes in water and/or sediment quality. Trend analyses will be updated annually …


Estimates Of Breeding Bird Populations In The Sheyenne National Grassland, North Dakota, Mary Ann Cunningham, Douglas Johnson, Daniel N. Svingen Mar 2006

Estimates Of Breeding Bird Populations In The Sheyenne National Grassland, North Dakota, Mary Ann Cunningham, Douglas Johnson, Daniel N. Svingen

The Prairie Naturalist

We conducted a two-year survey of breeding birds in the Sheyenne National Grassland, North Dakota, to estimate total populations of breeding birds. The Grassland is of interest because it provides wildlife habitat and recreational birding opportunities. Indicated breeding pairs were counted on 100-m wide belt transects during morning surveys from late May to early July in 2002 and 2003. We surveyed approximately 6 to 7% of the Grassland each year. The most abundant species in both years were grasshopper sparrow (Ammodramus savannarum), red-winged blackbird (Agelaius phoeniceus), claycolored sparrow (Spizella pallida), Savannah sparrow (Passerculus …


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 …


Fisheries Occasional Publication No. 29 - Western Rock Lobster Fishery Effects Of Fishing On The Ecosystem - Scientific Reference Group (Chairman's Report No. 3, February 2005), Department Of Fisheries, Western Australia Nov 2005

Fisheries Occasional Publication No. 29 - Western Rock Lobster Fishery Effects Of Fishing On The Ecosystem - Scientific Reference Group (Chairman's Report No. 3, February 2005), Department Of Fisheries, Western Australia

Fisheries Occasional Publications

The Western Rock Lobster Effects of Fishing on the Ecosystem Scientific Reference Group (the SRG) was convened jointly by the Department of Fisheries and the WA Fishing Industry Council (WAFIC). The SRG met on Tuesday 1 February 2005 at the Fremantle Sailing Club, and this document is the official report from that meeting.


A Five Year Management Strategy For Recreational Fishing On The South Coast. The Minister For Fisheries' Decision In Response To The Final Report Of The South Coast Recreational Fishing Working Group., Jon Ford (Minister For Fisheries; The Kimberley, Pilbara And Gascoyne) Sep 2005

A Five Year Management Strategy For Recreational Fishing On The South Coast. The Minister For Fisheries' Decision In Response To The Final Report Of The South Coast Recreational Fishing Working Group., Jon Ford (Minister For Fisheries; The Kimberley, Pilbara And Gascoyne)

Fisheries Management Papers

After careful consideration of the South Coast Recreational Fishing Working Group’s recommendations and the wide range of issues raised in submissions, I have made my decisions in respect to the future management arrangements for recreational fishing in South Coast Region. I believe the new management arrangements which will be implemented in 1 January 2006 will go a long way to protecting recreational fishing quality and meeting the long term needs for the sustainable management of recreational fishing. I did note that some of the most pressing concerns raised during public meetings, and in submissions, related to the interaction between the …


Proposals For Community Discussion : A Quality Future For The Recreational Marron Fishery : A Five-Year Draft Strategy To Ensure The Long-Term Sustainability Of The Marron Fishery, Recreational Freshwater Fisheries Stakeholder Sub-Committee Sep 2005

Proposals For Community Discussion : A Quality Future For The Recreational Marron Fishery : A Five-Year Draft Strategy To Ensure The Long-Term Sustainability Of The Marron Fishery, Recreational Freshwater Fisheries Stakeholder Sub-Committee

Fisheries Management Papers

While some of the factors threatening the future of the marron fishery can be managed via traditional fisheries controls, many fall outside of the Department of Fisheries’ jurisdiction and require a ‘whole of Government’ approach to management. To help ensure a quality future for the recreational marron fishery, the Recreational Freshwater Fisheries Stakeholder Sub-committee (RFFSS) has now developed a set of draft management proposals designed to form the basis of a five-year management plan for the fishery.


Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2004), Daniel M. Dauer Aug 2005

Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2004), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

Macrobenthic communities of the Elizabeth River watershed have been quantitatively sampled since summer 1999. This report presents the data from the sixth year of sampling in 2004. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of the tidal waters of the Elizabeth River watershed as indicated by the structure of the benthic communities. ( 2) To conduct trend analyses on long-term data at 14 fixed-point stations to relate temporal trends in the benthic communities to changes in water and/or sediment quality. Trend analyses will be updated …


Western Rock Lobster Fishery - Ecological Risk Assessment 2005 Report., Mark Burgman Jul 2005

Western Rock Lobster Fishery - Ecological Risk Assessment 2005 Report., Mark Burgman

Fisheries Management Papers

The first two parts of the document provide background on the western rock lobster fishery and its governance. The third and fourth parts outline reporting requirements for the Ecologically Sustainable Development process and the specifics of the risk assessment process applied here. These sections are based substantially on reports written earlier by the Department of Fisheries and distributed to participants in the risk assessment process. They have been edited here to include only the details that were pertinent to this risk assessment. Parts 5, 6 and 7 provide the outcomes of the hazard elicitation workshop with stakeholders and the subsequent …


A Five-Year Management Strategy For Recreational Fishing On The South Coast Of Western Australia. Final Report, South Coast Recreational Fishing Working Group. Jun 2005

A Five-Year Management Strategy For Recreational Fishing On The South Coast Of Western Australia. Final Report, South Coast Recreational Fishing Working Group.

Fisheries Management Papers

The development of this strategy represents a significant step in protecting recreational fishing quality in the South Coast Region and meeting the long-term needs for the sustainable management of recreational fishing. All recommendations contained in this report were made only after careful consideration of the submissions and issues which were raised at public meetings, along with the action needed to be taken to protect the long-term sustainability of our fish stocks.


2002 Licensed Angler Survey: Summarized Results, Keith L. Hurley, Kristin L. Duppong-Hurley May 2005

2002 Licensed Angler Survey: Summarized Results, Keith L. Hurley, Kristin L. Duppong-Hurley

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

On October 22, 2002, 5000 six-page surveys (Appendix 3) were sent to a stratified-random sample of Nebraska anglers drawn from the 2001 licensed anglers database. The database included all anglers who purchased a fishing license in 2001 as well as all lifetime fishing permit holders who purchased their license before or during 2001. The database did not include those possessing a free permit, such as veteran’s or senior citizen permits. The survey subsample (2.6% of the 2001-licensed angler database) was stratified such that the proportions of surveys in the subsample (4366 residents and 634 non-residents) matched the proportions of resident/non-resident …


Fisheries Occasional Paper No. 20 - Management Of Western Rock Lobster Fishery - Advice To Stakeholders - Assessment Of Southern Zone Resource Sustainability Options, Department Of Fisheries, Western Australia May 2005

Fisheries Occasional Paper No. 20 - Management Of Western Rock Lobster Fishery - Advice To Stakeholders - Assessment Of Southern Zone Resource Sustainability Options, Department Of Fisheries, Western Australia

Fisheries Occasional Publications

The management options presented in this paper have been developed in close cooperation with the rock lobster industry to address the short-term sustainability and economic concerns regarding the level of exploitation and its impact on the breeding stock in the southern region. The main focus in the short-term is to consider options that reduce fishing effort during periods that may be economically inefficient to fish and at the same time reduce the level of exploitation.

The management package does not address the serious long-term sustainability or socioeconomic issues (e.g. cost pressures and related fleet capacity) facing the industry. If the …


A Comparison Of Population Sizes And Number Of Captures For The Desert Woodrat (Neotoma Lepida) In Two Microhabitats In The Las Vegas Wash, Nevada, Jayson Barangan May 2005

A Comparison Of Population Sizes And Number Of Captures For The Desert Woodrat (Neotoma Lepida) In Two Microhabitats In The Las Vegas Wash, Nevada, Jayson Barangan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Planned removal and eradication of saltcedar in the Las Vegas Wash, Nevada could potentially generate adverse impacts on present desert woodrat (Neotoma lepida) populations inhabiting the area. Consequently, research was conducted investigating population sizes of N. lepida in two distinct microhabitat types, saltcedar (Tamarix sp.) and mesquite/quailbush (Prosopis sp./Atriplex lentiformis). The results of this study will aid in gauging the effects of the changes in vegetation once restoration work is completed and assist with logistical scheduling for implementation of control measures. Mark-recapture field techniques were utilized for data collection from July 2002 to June 2003. Population estimates were calculated using …


A Sustainable Future For Recreational Fishing In The Cocos (Keeling) Islands. Proposal For Discussion., Department Of Fisheries. Mar 2005

A Sustainable Future For Recreational Fishing In The Cocos (Keeling) Islands. Proposal For Discussion., Department Of Fisheries.

Fisheries Management Papers

Fishing activity on the Cocos is essentially unmanaged at present and there has been some condern by the local community that a number of species, such as coral trout, have declined in numbers over the last decade. This draft strategy was developed by the Western Australian Department of Fisheries who now has responsibility for managing recreational fishing on behalf of the Commonwealth Department of Transport and Regional Services.


Fisheries Research Report No. 148 - Historical Distribution And Abundance Of The Australian Sea Lion (Neophoca Cinerea) On The West Coast Of Western Australia, Richard Campbell Mar 2005

Fisheries Research Report No. 148 - Historical Distribution And Abundance Of The Australian Sea Lion (Neophoca Cinerea) On The West Coast Of Western Australia, Richard Campbell

Fisheries Research Reports

Analysis of historical patterns of abundance of the Australian sea lion on the west coast of Western Australia suggests that the population size was greater prior to the impacts of colonization and commercial sealing/whaling between the 18th and 20th centuries. In addition, it is evident that there has been a reduction in the number of breeding sites along the west coast, particularly around the greater Perth metropolitan area. There is limited evidence of the impact of indigenous hunting on the abundance and distribution of this species. The major impacts on Australian sea lion populations were a combination of subsistence and …


Integrated Fisheries Management Report Western Rock Lobster Resource., Department Of Fisheries Feb 2005

Integrated Fisheries Management Report Western Rock Lobster Resource., Department Of Fisheries

Fisheries Management Papers

This report is the first in a series of Integrated Fisheries Management (IFM) reports required under the 2004 Government Policy on IFM. Under this policy, the Executive Director of Fisheries is required to approve a sustainability report for each fishery, which includes a clear statement on the harvest level. The sustainable harvest level is that total catch, or catch range, that is to be allocated among the various user groups identified for that particular fishery. These IFM reports will assist in the process of allocating explicit shares in the use of Western Australia’s fish resources. They do not establish the …


Optimizing Allocation Of Monitoring Effort Under Economic And Observational Constraints, Scott A. Field, Andrew J. Tyre, Hugh P. Possingham Jan 2005

Optimizing Allocation Of Monitoring Effort Under Economic And Observational Constraints, Scott A. Field, Andrew J. Tyre, Hugh P. Possingham

School of Natural Resources: Faculty Publications

Efforts to design monitoring regimes capable of detecting population trends can be thwarted by observational and economic constraints inherent to most biological surveys. Ensuring that limited resources are allocated efficiently requires evaluation of statistical power for alternative survey designs. We simulated the process of data collection on a landscape, where we initiated declines over 3 sample periods in species of varying prevalence and detectability. Changing occupancy levels were estimated using a technique that accounted for effects of false-negative errors on survey data. Declines were identified within a frequentist statistical framework, but the significance level was set at an optimal level …


Monitoring Temporal Change In Riparian Vegetation Of Great Basin National Park, E. A. Beever, D. A. Pyke, J. C. Chambers, F. Landau, S. D. Smith, K. Murray Jan 2005

Monitoring Temporal Change In Riparian Vegetation Of Great Basin National Park, E. A. Beever, D. A. Pyke, J. C. Chambers, F. Landau, S. D. Smith, K. Murray

Life Sciences Faculty Research

Disturbance in riparian areas of semiarid ecosystems involves complex interactions of pulsed hydrologic flows, herbivory, fire, climatic effects, and anthropogenic influences. We resampled riparian vegetation within ten 10-m × 100-m plots that were initially sampled in 1992 in 4 watersheds of the Snake Range, east central Nevada. Our finding of significantly lower coverage of grasses, forbs, and shrubs within plots in 2001 compared with 1992 was not consistent with the management decision to remove livestock grazing from the watersheds in 1999. Change over time in cover of life-forms or bare ground was not predicted by scat counts within plots in …


Access And Allocation Arrangements For The Commercial 'Wetline' Fisheries. Proposals For Discussion., Commercial Access Panel Jan 2005

Access And Allocation Arrangements For The Commercial 'Wetline' Fisheries. Proposals For Discussion., Commercial Access Panel

Fisheries Management Papers

The Minister for Fisheries established this review of open access (wetline) commercial fishery arrangements to provide a more effective management framework for wetline fishing and to complement the recreational initiatives. This must involve the removal of excess fishing capacity, including latent effort, from the fishery and the establishment of a dedicated commercial fishery with clear entry criteria and an appropriate limit on catch in each bioregion. However it must be made clear that the ‘wetline review’ is not a sectoral resource sharing exercise. Following the implementation of new management arrangements for the ‘wetline’ fisheries, the appropriateness of the existing levels …