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Rock Lobster Industry Advisory Committee Report To The Minister For Fisheries., Rock Lobster Industry Advisory Committee Jan 1989

Rock Lobster Industry Advisory Committee Report To The Minister For Fisheries., Rock Lobster Industry Advisory Committee

Fisheries Management Papers

The total catch of about 12.1 million kilograms for the 1987/88 season, based on processor returns, was an increase of 44% on the 1986/87 season. This very high catch, the third highest on record, resulted from an above average perulus settlement in 1983/84 and a "flow-on" of fast growing animals stemming from the expected high recruitment in 1988/990 caught as "reds" in 1987/88.

The Committee has identified five major elements related to the state of the rock lobster fishery upon which management advice is considered.

a) The undersize fraction of the population.

b) The "whites" which provide a significant proportion …


Nesting Dynamics Of The Eastern Bluebird (Sialia Sialis) In Southeastern Illinois, Susan E. Nelle Jan 1989

Nesting Dynamics Of The Eastern Bluebird (Sialia Sialis) In Southeastern Illinois, Susan E. Nelle

Masters Theses

Data collected from 1981 through 1988 from an Eastern Bluebird (Sialia sialis) nesting box trail, involving 512 nests and 2176 eggs, in Crawford County, Illinois, were analyzed and compared to similar published works. The average nesting season lasted 167.4 days, ran from 17 March through 31 August, and was divided into three breeding peaks (or phases). Most breeding pairs were observed with either one or two clutches per season; however, triple-brooded pairs were also present, the clutches of which coincided well with the three peaks. Most data showed a decrease as the season progressed. For example, mean clutch …


Some Factors Affecting Male Mating Success In The Giant Waterbug (Belostoma Flumineum Say), Karyn S. Crisman Jan 1989

Some Factors Affecting Male Mating Success In The Giant Waterbug (Belostoma Flumineum Say), Karyn S. Crisman

Masters Theses

Giant waterbugs (Subfamily Belostomatinae) are interesting in that males provide exclusive post-copulatory care of young. This unusual behavior makes this species an excellent study system for investigations of sexual selection theory because in such systems, sex role reversals are predicted. Previous studies indicate that role reversal in giant waterbugs is not complete because males still court females. It is assumed that from this courtship display females can assess male quality and "choose" a superior male. If some males are chosen over others then differential mating success results. This study was undertaken to ascertain some of the factors that affect male …


Dental Pathology In Selected Carnivores From Arkansas, C. Renn Tumlison, J. D. Wilhide, V. Rick Mcdaniel Jan 1989

Dental Pathology In Selected Carnivores From Arkansas, C. Renn Tumlison, J. D. Wilhide, V. Rick Mcdaniel

Journal of the Arkansas Academy of Science

The occurrence and kinds of dental pathology in wild carnivore populations in Arkansas were investigated through examination of 1295 skulls of bobcat (Felis rufus), river otter (Lutra canadensis), gray fox (Urocyon cinereoargenteus), coyote (Canis latrans), and raccoon (Procyon lotor). Pulpitis or abscesses in broken or otherwise exposed teeth were noted in all species, but bobcats had the fewest exposures while otter and gray foxhad the most. Osteomyelitis occurred in all species except the bobcat. Caries were noted in the coyote, raccoon, and gray fox. Otter and coyote had alveolar thinning, and coyote had enamel dysplasia and maxillary sinusitis.


Lasting Responsiveness Of A Kea (Nestor Notabilis) Toward Its Mirror Image, Judy Diamond, Alan B. Bond Jan 1989

Lasting Responsiveness Of A Kea (Nestor Notabilis) Toward Its Mirror Image, Judy Diamond, Alan B. Bond

Papers in Behavior in Biological Sciences

At the San Diego Zoo we had the opportunity of observing the behaviour of a Kea Nestor notabilis toward its mirror image under conditions of constant exposure over a period of 12 months. ... The introduction of the mirrors appears to have had a striking impact on the bird's listless state. Reports from keepers indicated that the Kea's appetite was restored after the introduction of the mirrors, and the animal was generally more active. Incidents of feather pulling were generally reduced in frequency.


Studies Of Learning And Memory In Natural Contexts : Integrating Functional And Mechanistic Approaches To Behavior, Alan Kamil Jan 1989

Studies Of Learning And Memory In Natural Contexts : Integrating Functional And Mechanistic Approaches To Behavior, Alan Kamil

Papers in Behavior in Biological Sciences

My purpose in this paper is to describe two research projects that combine experimental psychology and behavioral ecology . The first employs the operant conditioning technology developed by psychologists to test hypotheses arising from ecological studies of foraging animals. The second uses concepts from natural history and ecology to explore the nature and evolution of spatial memory. These two projects demonstrate both the advantages and the challenges of interdisciplinary work.

There are many advantages to combining psychological and biological perspectives on the behavior of animals. But truly interdisciplinary work is rare, mostly because it is so difficult to achieve meaningful …


Toward A Resolution Of The Paradox Of Aggressive Displays: I. Optimal Deceit In The Communication Of Fighting Ability, Alan B. Bond Jan 1989

Toward A Resolution Of The Paradox Of Aggressive Displays: I. Optimal Deceit In The Communication Of Fighting Ability, Alan B. Bond

Papers in Behavior in Biological Sciences

One inference from game theory models of animal conflict is that adversaries should not inform one another about concealed components of their fighting ability. This poses a paradox for the customary ethological account of aggressive displays in that it is usually assumed that the primary function of such behavior is to make such information available. To resolve the paradox, I propose that the information in aggressive displays may not be strictly truthful, but may instead represent "optimal deceit," a balance between the advantages of deceit or bluffing and the disadvantages of selecting for skepticism in the receiver. Numerical simulation of …


Toward A Resolution Of The Paradox Of Aggressive Displays: Ii. Behavioral Efference And The Communication Of Intentions, Alan B. Bond Jan 1989

Toward A Resolution Of The Paradox Of Aggressive Displays: Ii. Behavioral Efference And The Communication Of Intentions, Alan B. Bond

Papers in Behavior in Biological Sciences

An inference from game-theory models of animal conflict is that adversaries should not inform one another about their level of aggressive motivation. This poses a paradox for the traditional ethological account of graded aggressive displays because it is usually assumed that the adaptive significance of these behavior patterns lies in their making such information available. To resolve the paradox, I propose that communication is only an incidental effect of displays, and that their primary adaptive function is regulation of the intensity of aggressive encounters through positive feedback on aggressive motivation, a process termed "behavioral efference." Evidence in support of this …


Geographic Distribution: Lampropeltis C. Calligaster (Prairie Kingsnake). Usa: Nebraska: Thayer Co., Louis A. Somma, John F. Lokke Jan 1989

Geographic Distribution: Lampropeltis C. Calligaster (Prairie Kingsnake). Usa: Nebraska: Thayer Co., Louis A. Somma, John F. Lokke

Papers in Herpetology

LAMPROPELT/S C. CALL/GASTER (Prairie Kingsnake). USA: NEBRASKA: Thayer Co.: Hubbell: unmarked section road ca. 0.4km S of State Hwy 8 (T1N. R1W, SW corner S29). 11 June 1988. L. A. Somma and J. F. Lokke. Verified by J. F. Lokke and L. A. Somma. University of Nebraska at Omaha Herpetological Collection c/o J. D. Fawcett (101-11-688). Road killed adult. New county record, extends range ca. 18.5km W of record in adjacent Jefferson Co. (lynch 1985. Trans. Nebraska Acad. Sci. 13:33-57). Represents most northwesterly record in USA (Blaney 1979. Cat. Amer. Amph. Rept (229):1-2).


Elaphe Bairdi (Baird’S Rat Snake): Drinking Behavior., Louis A. Somma Jan 1989

Elaphe Bairdi (Baird’S Rat Snake): Drinking Behavior., Louis A. Somma

Papers in Herpetology

On 13 February 1988. at 1600 h. a captive-bred (hatched July 1985) male Elaphe bairdi (TL.136.9 cm, SVL .. 89.54 cm). maintained in a 50.5 x 25 x 30 cm terrerium was accidently splashed with water. As beads of water on the snake's head rolled down to the upper labial sceles. swallowing was observed. The water on the labial scales was drawn Into the mouth while It was closed. This behavior lasted 42 sec. This behavior was repeated 23 out of 24 trials conducted during the next 24 days. The duration of swallowing wes 9-62 sec (avg 35.8, N = …


Scaptomyza Nigrita Wheeler (Diptera: Drosophilidae), A Leaf Miner Of The Native Crucifer, Cardamine Cordifolia A. Gray (Bittercress), S. K. Collinge, Svata M. Louda Jan 1989

Scaptomyza Nigrita Wheeler (Diptera: Drosophilidae), A Leaf Miner Of The Native Crucifer, Cardamine Cordifolia A. Gray (Bittercress), S. K. Collinge, Svata M. Louda

Svata M. Louda Publications

The biology of Scaptomyza nigrita on its host plant, a native crucifer (Bittercress) in the Rocky Mountains, is described. Development of each stage in the life history was studied both in the field and in the laboratory. This is the first documentation of a host for S. nigrita. We examined the activity of adult flies in two adjacent habitats, sun and adjacent willow shade. Adult flies were more abundant on bittercress plants in sun-exposed versus in shaded areas, and were most active from mid-day to late afternoon. Female flies were significantly larger than male flies, but there were no differences …


Toward A Resolution Of The Paradox Of Aggressive Displays: Ii. Behavioral Efference And The Communication Of Intentions, Alan B. Bond Jan 1989

Toward A Resolution Of The Paradox Of Aggressive Displays: Ii. Behavioral Efference And The Communication Of Intentions, Alan B. Bond

Papers in Behavior in Biological Sciences

An inference from game-theory models of animal conflict is that adversaries should not inform one another about their level of aggressive motivation. This poses a paradox for the traditional ethological account of graded aggressive displays because it is usually assumed that the adaptive significance of these behavior patterns lies in their making such information available. To resolve the paradox, I propose that communication is only an incidental effect of displays, and that their primary adaptive function is regulation of the intensity of aggressive encounters through positive feedback on aggressive motivation, a process termed "behavioral efference." Evidence in support of this …


The Bats Of Fountain Cavern, Hugh H. Genoways Jan 1989

The Bats Of Fountain Cavern, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

First paragraph:

During May 1988, two species of bats--Brachyphylla cavernarum (Antillean cave bat) and Natalus stramineus (funnel-eared bat)--were captured at the opening of Fountain Cavern. Only Brachyphylla cavernarum was captured inside of the cave. The weather was extremely wet during our visit to Anguilla so our work in Fountain Cavern was limited by hazardous conditions. Nevertheless, we did make a thorough survey of the bats inside the cave. There is only one other species on Anguilla--Monophyllus redmani (Antillean long-tongued bat)--that might be expected to utilize Fountain Cavern as a roosting site.

Includes the author's recommendations about conservation for …


Caribbean Island Zoogeography: A New Approach Using Mitochondrial Dna To Study Neotropical Bats, Carleton J. Phillips, Dorothy E. Pumo, Hugh H. Genoways, Phillip E. Ray Jan 1989

Caribbean Island Zoogeography: A New Approach Using Mitochondrial Dna To Study Neotropical Bats, Carleton J. Phillips, Dorothy E. Pumo, Hugh H. Genoways, Phillip E. Ray

University of Nebraska State Museum: Mammalogy Papers

Genetic analysis of animal mitochondrial DNA is a new and valuable addition to the battery of techniques available to zoogeographers. This paper describes characteristics of mitochondrial DNA (mtDNA) that make it applicable for the study of island zoogeography.

Some traditional zoogeographic questions are examined using mtDNA from the Neotropical fruit bat, Artibeus jamaicensis. The specific questions are: 1) To what extent are island populations isolated (that is, does interbreeding occur between the insular subspecies)? 2) Can a single founding female account for the mitochondrial genomes on specific islands in the Antilles? 3) Is there a correlation between the genomic …


Temporal And Spatial Variation In Pelagic Fish Abundance In Lake Mead Determined From Echograms, Gene R. Wilde, Larry J. Paulson Jan 1989

Temporal And Spatial Variation In Pelagic Fish Abundance In Lake Mead Determined From Echograms, Gene R. Wilde, Larry J. Paulson

Publications (WR)

Echograms have been used extensively to locate and estimate the relative abundance of marine fish stocks (Cushing 1973). In freshwater, echograms have been used to describe vertical (Netsch et al. 1971; Eggers 1978; O'Brien et al. 1984; Matthews et al. 1985), spatial (O'Brien et al. 1984; Wanjala et al. 1986) and temporal (Baker and Paulson 1983) patterns in fish abundance. Although most uses of echograms have been qualitative, Mullan and Applegate (1969) and Matthews et al. (1985) obtained relative estimates of fish abundance by counting targets (fish) on echograms. However, neither Mullan and Applegate (1969) nor Matthews et al. (1985) …


The Prairie Naturalist Volume 20, No. 4. December 1988 Dec 1988

The Prairie Naturalist Volume 20, No. 4. December 1988

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

TABLE OF CONTENTS

RANGE PLANT COMMUNITIES OF THE CENTRAL GRASSLAND RESEARCH STATION IN SOUTH CENTRAL NORTH DAKOTA ▪ C. L Lura, W. T. Barker, and P. E. Nyren

SEASONAL PATTERNS IN SAMPLING DATA FOR LARGEMOUTH BASS AND BLUE GILLS IN A NORTHERN GREAT PLAINS IMPOUNDMENT ▪ E. A. Bettross and D. W. Willis

INTRODUCTION, ESTABLISHMENT, AND DISPERSAL OF WESTERN MOSQUITOFISH IN NEBRASKA (ACTINOPTERYGII: POECILIIDAE) ▪ J. D. Lynch

OBSERVATIONS ON THE ECOLOGY OF CHIGGERS (ACARI: TROMBICULIDAE) FROM SOUTH DAKOTA ▪ E. R. Easton and W. …


Colony Survivorship In Pogonomyrmex Occidentalis, Western Harvester Ant, In Western Nebraska, Kathleen H. Keeler Nov 1988

Colony Survivorship In Pogonomyrmex Occidentalis, Western Harvester Ant, In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Little is known about the life span of individual ant colonies (Keeler, 1981), even though the dynamics of some species, such as harvester ants, are crucial to the structure of plant and animal communities (e.g., Brown et al., 1979). This note reports the results of 10 years of observations on a population of harvester ants.

Fifty-six mounds of Pogonomyrmex occidentalis Cresson (Hymenoptera: Formicidae), western harvester ant, were permanently marked with aluminum tags in August 1977. The site, about 1 ha just south of the University of Nebraska's Cedar Point Biological Station, Keith Co., Nebraska, was within a pasture subject to …


A Review Of The Pacific Members Of The Gobiid Fish Genus Bollmannia Jordan, Robin L. Bedenbaugh Oct 1988

A Review Of The Pacific Members Of The Gobiid Fish Genus Bollmannia Jordan, Robin L. Bedenbaugh

Biological Sciences Theses & Dissertations

The Pacific members of the genus Bollmannia Jordan 1890 comprise seven species of gobies distributed from Baja California to Peru and west to the Galapagos Archipelago.

Previous authors recognized nine nominal species, all known only from their brief original accounts. Those accounts do not allow for proper discrimination of the species. All nominal species were re­ examined using meristic, morphometric, and pigment-pattern characteristics. Three of the nine nominal species are herein considered synonymous with previously described forms. The six valid nominal species are redescribed, a new species is described, and a key and illustrations are provided for the seven valid …


Effects Of Ammonia, Salinity And Oxygen On The Growth And Energetics Of The Grass Shrimp, Palaemonetes Pugio, Ahmad Mohammed Altayaran Jul 1988

Effects Of Ammonia, Salinity And Oxygen On The Growth And Energetics Of The Grass Shrimp, Palaemonetes Pugio, Ahmad Mohammed Altayaran

Biological Sciences Theses & Dissertations

The growth and energy budget of juvenile grass shrimp, Palaemonetes pugio, were examined under various combinations of ammonia, salinity and dissolved oxygen. Experiments were performed to determine the effects of multiple stresses on the growth and physiological processes of the shrimp. The experimental design also allowed an evaluation of the effectiveness of several techniques for determining the productivity potential of aquatic animals exposed to stress.

A flow-through system was used to produce combinations of ammonia concentrations (0, 3, 6 and 12 mg/l) and salinities (20, 25, 30 and 35 ppt) for 21-day tests. The tests were conducted at high …


Comparative Analysis Of The Effects Of Visual And Auditory Stimuli On Avian Mobbing Behavior, C. Ray Chandler, Robert K. Rose Jul 1988

Comparative Analysis Of The Effects Of Visual And Auditory Stimuli On Avian Mobbing Behavior, C. Ray Chandler, Robert K. Rose

Biological Sciences Faculty Publications

Both visual and auditory stimuli elicit avian mobbing behavior, but there is little comparative information on their isolated and additive effects. Using three combinations of two experimental stimuli (mount and tape of an Eastern Screech-Owl, Otus asio) we tested the effects of stimuli on the frequency, intensity, and duration of avian mobbing behavior. Of 169 mount-only trials, only 11 (6.5%) were successful in attracting birds. Tape-only (n = 169) and mount-and-tape (n = 170) were equally successful in attracting birds (approximately 85% of all trials), but mount-and-tape trials were more likely to initiate mobbing behavior. Birds responding …


Fisheries Management Paper No. 15 - Draft Management Plan For The Control Of Barramundi Gillnet Fishing In The Kimberley., R. S. Brown Jun 1988

Fisheries Management Paper No. 15 - Draft Management Plan For The Control Of Barramundi Gillnet Fishing In The Kimberley., R. S. Brown

Fisheries Management Papers

This management plan sets out a number of options for the control of commercial gillnet fishing for barramundi in the Kimberley. the plan focuses on existing commercial fishery, and on the fishermen consulted during the process of developing these management arrangements. However, the barramundi stocks of the region are increasingly exploited by large numbers of both local and tourist recreational fishermen whose needs must also be catered for. Because recreational fishermen are not easily identified or contacted as a group, I have endeavoured in this foreword, to set out the management options which best take into account the future needs …


Economics And Marketing Of Western Australia Pilchards., Scp Fisheries Consultants Pty Ltd Jun 1988

Economics And Marketing Of Western Australia Pilchards., Scp Fisheries Consultants Pty Ltd

Fisheries Management Papers

The 1986/87 Australian catch was about 8,300 tonnes. At present levels of fishing,it has been suggested that this could be substantially increased. The fishery is not in danger of over-exploitation. Rather, the problem could be that there is more fish available than existing markets could absorb. However, there are prospects for increasing the present volume of fish sold domestically and for developing new products and markets in Australia and overseas.


Echinococcus Vogeli Rausch And Bernstein, 1972, From The Paca, Cuniculus Paca L. (Rodentia: Dayproctidae), In The Departamento De Santa Cruz, Bolivia, Scott Lyell Gardner, Robert L. Rausch, Otto Carlos Jordan Camacho Jun 1988

Echinococcus Vogeli Rausch And Bernstein, 1972, From The Paca, Cuniculus Paca L. (Rodentia: Dayproctidae), In The Departamento De Santa Cruz, Bolivia, Scott Lyell Gardner, Robert L. Rausch, Otto Carlos Jordan Camacho

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Among approximately 2,000 mammals examined for helminths in various regions of Bolivia during 1983-1987, cysts of Echinococcus vogeli Rausch and Bernstein, 1972, were found in a single paca, Cuniculus paca L., collected at La Laguna, Departamento de Santa Cruz (lat. 16° 36' W; long. 62° 42' S). This record, the first from Bolivia, represents a considerable extension of the known geographic range of this species in South America. Upon analysis of the morphologic characteristics of the protoscoleces derived from the cysts, the sizes of rostellar hooks from the material from the paca were found to be well within the ranges …


Characterization Of The Aquatic Environment In Lake Mead Near The Proposed Spring Canyon Pumped-Storage Project, And Assessment Of Potential Aquatic Impacts, Charles R. Liston, Stephen J. Grabowski, Bureau Of Reclamation Jun 1988

Characterization Of The Aquatic Environment In Lake Mead Near The Proposed Spring Canyon Pumped-Storage Project, And Assessment Of Potential Aquatic Impacts, Charles R. Liston, Stephen J. Grabowski, Bureau Of Reclamation

Publications (WR)

A pumped storage system consists of an upper reservoir and lower reservoir separated by an elevation difference. During low demand energy periods such as nights and weekends water is pumped from the lower to the upper reservoir using available energy from conventional steam electric power plants. During high energy demand periods, such as mornings and afternoons of weekdays, upper reservoir water is allowed to drop back down through the same system of water conduits and turbines, generating electricity to conveniently meet abrupt electrical energy requirements. The same water turbines thus act both as pumps and as conventional hydroelectric turbines. Because …


Callianassa Trilobata (Crustacea: Thalassinidea) Influences Abundance Of Meiofauna And Biomass, Composition, And Physiologic State Of Microbial Communities Within Its Burrow, Fred C. Dobbs, James B. Guckert Jun 1988

Callianassa Trilobata (Crustacea: Thalassinidea) Influences Abundance Of Meiofauna And Biomass, Composition, And Physiologic State Of Microbial Communities Within Its Burrow, Fred C. Dobbs, James B. Guckert

OES Faculty Publications

Biochemical and traditional methods were used to determine the influence of Callianassa trilobata on microbiological and meiofaunal communities within its large, highly consolidated burrow. Sediment was collected from the lining of the shrimp's burrow, the burrow matrix, and ambient, subsurface sediment. The lining and matrix were composed of poorly sorted, fine-grained material compared to sandy ambient sediment. Meiofauna, predominantly nematodes, were most abundant in ambient sediment, not in the burrow as has been found for other species of macrofauna. Concentrations of chlorophyll a were very high in the lining, consistent with the suggestion that C. trilobata lines its burrow walls …


Microbial Food Resources Of The Macrofaunal-Deposit Feeder Ptychodera Bahamensis (Hemichordata: Enteropneusta), Fred C. Dobbs, James B. Guckert Jun 1988

Microbial Food Resources Of The Macrofaunal-Deposit Feeder Ptychodera Bahamensis (Hemichordata: Enteropneusta), Fred C. Dobbs, James B. Guckert

OES Faculty Publications

Biochemical and traditional analyses were used to characterize the microbial food resources and digestive efficiency of Ptychodera bahamensis, an enteropneust hemichordate. Sediment was collected from freshly extruded fecal casts and adjacent feeding depressions. There were no significant differences between casts and depressions in median grain size, percent silt-clay, density of total meiofauna and of nematodes, and concentrations of chlorophyll a and phaeophytin. Nematodes in casts had a median diameter greater than those in depressions. Measures of total, viable microbial biomass were 30% (total phospholipid, ester-linked fatty acids) and 49% (extractible phospholipid phosphate) lower in casts. Concentrations of 33 fatty …


Assessing Population Trends Of New-Hampshire Forest Birds: Local Vs Regional Patterns, Richard T. Holmes, Thomas W. Sherry May 1988

Assessing Population Trends Of New-Hampshire Forest Birds: Local Vs Regional Patterns, Richard T. Holmes, Thomas W. Sherry

Dartmouth Scholarship

We examined the changes in abundance between 1969 and 1986 of 19 forest-dwelling, mostly migratory bird species breeding in New Hampshire at 2 different scales: one local (an intensively studied 10-ha plot in unfragmented forest) and the other regional (Breeding Bird Surveys statewide). Twelve of the 19 species exhibited similar trends at both scales. Eight neither increased nor decreased, and 4 (Least Flycatcher, Winter Wren, Wood Thrush, and Swainsoh's Thrush) declined significantly. Others increased, decreased, or re-mained steady at one or the other scale. Overall, more species declined than increased both locally (8 vs. 1) and regionally (5 vs. 1). …


Inter-Seasonal Range Relationships Of Spanish Goats And Mule Deer In A Utah Oakbrush Community, Robert Alexander Riggs May 1988

Inter-Seasonal Range Relationships Of Spanish Goats And Mule Deer In A Utah Oakbrush Community, Robert Alexander Riggs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three experiments were conducted to assess the potential for using Spanish goats to manage Gambel oakbrush winter range, dominated by Gambel oak (Quercus gambelii), for mule deer (Odocoileus hemionus). Summer-time food selection of goats, effects on plant community composition, and consequent effects on mule deer nutrition and foraging behavior were examined.

An apparent preference for juvenile oak browse, and low use of oak twigs was observed. Selection for juvenile browse may have been facilitated by the retarded phenology of oak as compared to that of associated flora. This differential was maintained by repeated browsing. Animal performance, …


Pastoral Development Strategies In The Sahel And East Africa: Can The Mistakes Be Corrected?, Ahmed Musa Haji Ahmed May 1988

Pastoral Development Strategies In The Sahel And East Africa: Can The Mistakes Be Corrected?, Ahmed Musa Haji Ahmed

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

There is much controversy on the definition given to those people who raise livestock on the natural vegetation. Differences in the degree of their dependence on livestock and livestock products for food, as well as differences in the patterns of their movements, create the controversy. "Pure-pastoralists", "nomadic pastoralists", "semi - pastoralists", "semi-nomadic", "transhumant", and "semisedentary" are but some of the many terms used in the literature to describe them (see, for example, Johnson, 1969; Jacobs, 1965; McGee, 1986; Horowitz, 1981). To avoid much of the confusion created by the use of these terms, we use the definition of pastoralists as …


Control And Evaluation Of Big Game Browsing Damage To Commercial Fruit Orchards, William E. Stone May 1988

Control And Evaluation Of Big Game Browsing Damage To Commercial Fruit Orchards, William E. Stone

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diversionary feeding, artificial feeding designed to divert animals away from areas where they might cause property damage, was tested for efficacy in reducing fruit orchard browsing by big game animals during two consecutive winters in Utah. Strategically placed attractive feedstuffs lured deer to feed stations and reduced fruit-bud browsing (1st year, P < 0.07; 2nd year, P < 0.01). Blossom and apple numbers were greater (P < 0.05) on trees in the feed (treatment) orchard than in the no feed (control) orchard in each year. However, higher (P < 0.05) apple production on trees where browsing was excluded in the treatment orchards compared to the control orchards indicated that intercept feeding did not increase crop production. Tree periodicity and other factors affecting apple production masked the effect of diversionary feeding on crop yield.

Two independent browsing damage assessment methods, a paired-tree technique and a harvest-inflation technique, predicted that the ratio of apples lost per browsed bud was 0.158 and 0.082, respectively. However, the values of the ratio varied widely with each method of estimation. Browsing damage differed ( …