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13.1.15. Life History And Habitat Needs Of The Black Brant, Dirk V. Derksen, David H. Ward

Waterfowl Management Handbook

The black brant is a sea goose that depends on coastal habitats from high arctic nesting sites in Canada, Alaska, and Russia to wintering areas in the Pacific coastal states, the Baja California peninsula, and mainland Mexico estuaries. Population estimates are based on aerial surveys in Mexico, California, Oregon, and Washington during mid-winter. Despite much annual variability in estimates, a plot of the counts from 1964 to 1992 reveals a significant downward trend in the winter populations (Fig. 1). Three of four major colonies on the Yukon&#;Kuskokwim (Y&#;K) delta declined an average of 60% during the first half of the …

The Iowa Science Teachers 1993 Fall Conference, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Luncheon Speaker ... 2-3
Exhibitor Checkoff ... 4
Raffle ... 5
Door Prizes ... 6 - 8
Housing Information ... 9
Concurrent Sessions I ... 10
Concurrent Sessions II ... 14
Concurrent Sessions III ... 19
Luncheon Information ... 24
Conference Registration Form ... Centerfold
Application for Membership ... Centerfold
Concurrent Sessions IV ... 25
Concurrent Sessions V ... 30
Corporate Sponsors ... 35
Exhibitors ... 36-37
Science Center of Iowa ... 38
Map ... 39
Acknowledgments ... 40
ISTS Officers and Regional Directors ... Inside Back Cover

Inhibition Of Total Gas And Methane Production In Anaerobic Digestion By Various Toxicants, Steven H. Malehorn

Masters Theses

Heavy metal inhibition of anaerobic digestion of municipal sewage sludge has been investigated over the past 50 years. Many assays began with steady-state conditions and observed the rate at which total gas or methane production decreased due to toxicant inhibition. These methods required considerable time and labor. Modified Warburg respirometers and serum bottle assays reduced much of the effort, but each method has limitations in terms of complexity, cost, and accuracy.

This series of experiments had two objectives: 1) develop a quick, inexpensive, and easy method to measure methanogenic activity in anaerobic digesters, and 2) determine median inhibitory concentrations (IC …

A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver

Faculty Publications and Presentations

Giant salvinia (Salviniaceae) is a potentially serious aquatic weed that is native to Brazil. It has been reported in more than 20 countries, but is not established in the U.S. at this time. Mitchell and Tur (1975) reported that three years after the formation of the Kariba Reservoir in Africa, giant salvinia blanketed 21.5% or 1003 km2 of the reservoir surface area. Creagh (199111992) wrote, "A single small plant may grow to form a thick mat covering more than 100 sq. km. in just three months - choking lakes and waterways, reducing populations of aquatic plants and animals and in …

Winter 1993, Nsu Oceanographic Center

Currents

No abstract provided.

Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth

All Peer-Reviewed Publications

Trypanosoma (Nannomonas) congolense comprises morphologically identical but genetically heterogeneous parasites infective to livestock and other mammalian hosts; three different genotypes of this parasite have been described previously. Restriction enzyme fragment length polymorphisms (RFLPs) in both kinetoplast DNA minicircle and nuclear DNA sequences, and randomly amplified polymorphic deoxyribonucleic acid (RAPD) patterns have been used here to demonstrate the existence of another type of T. (N.) congolense that is genotypically distinct from those that have so far been characterized at the molecular level. A highly repetitive, tandemly arranged DNA sequence and oligonucleotide primers, for use in polymerase chain reaction (PCR) amplification are …

A Reproductive-Resting Stage In An Harpacticoid Copepod, And The Significance Of Genetically Based Differences Among Populations, D. J. Lonsdale, P. Weissman, Fred C. Dobbs

OES Faculty Publications

Dormancy is an important life-history strategy which allows copepods to increase their fitness by delaying growth and reproduction until harsh environmental conditions have ameliorated. For marine species, the primary strategies identified to date include the production of dormant eggs by shallow-water species, and copepodite overwintering in deep-water species. Herein, we describe a third strategy in which fertilized adult females enter a “reproductive-resting” stage during the late fall that allows them to overwinter and provide a first source of spring naupliar recruitment. This strategy has been observed in the estuarine copepod Coullana canadensis, but may also occur in other species. …

Remote Detection Of Coral 'Bleaching' Using Pulsed-Laser Fluorescence Spectroscopy, J. T. Hardy, F. E. Hoge, J. K. Yungel, Richard E. Dodge

Marine & Environmental Sciences Faculty Articles

Despite their biological and economic importance coral reefs are increasingly threatened by human activities. Recently, 'bleaching' of reefs, i.e. loss of photosynthetic pigmentation, has occurred at numerous globally-distributed sites. A number of environmental stressors, including increased water temperature, can induce bleaching. Several investigators have suggested that the widespread occurrence of coral bleaching represents an early warning signal of global greenhouse warming. Regardless of the cause, the extent of coral bleaching, both regionally and globally, needs to be documented and monitored. We conducted laboratory studies to evaluate the potential of using remotely-sensed laser-induced fluorescence to monitor coral pigmentation. Five species of …

Resource Law Notes Newsletter, No. 26, Fall Issue, Sept. 1992, University Of Colorado Boulder. Natural Resources Law Center

Resource Law Notes: The Newsletter of the Natural Resources Law Center (1984-2002)

No abstract provided.

Wildlife Damage News, Volume 3, Summer/Fall 1992

Wildlife Damage News

CONTENTS:
New York's Beaver Management Program: An Update
Species Profile—White-tailed Deer
1992 Bureau of Wildlife Coyote Damage Control Workshop
Norplant for Beavers?
Harvest Season Wildlife Damage Reminders
Birds of Prey Assist Farmers
Putting People First

Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto

Natural Resources Management and Environmental Sciences

Individual trees of giant sequoia (Sequoia gigantea [Lindl.] Decne.) have demonstrated a capacity to attain both a long life and very large size. It is not uncommon to find old-growth giant sequoia trees in their native range that are 1,500 years old and over 15 feet in diameter at breast height. The ability of individual giant sequoia trees to survive over such long periods of time has often been attributed to the species high resistance to disease, insect, and fire damage. Such a statement, however, is a gross oversimplification, given broader ecosystem and temporal interactions. For example, why isn't …

Irreversible Immobilization Of Heavy Metal, Hyoung-Seog Ko

Theses

Heavy metals are contaminants of both solid and liquid wastes. For example, the ash produced from the incineration of domestic or industrial wastes often contains substantial concentration of lead, mercury, cadmium and other heavy metals that make it a hazardous waste. These heavy metals in wastes are hazardous because they are mobile. Immobilization of the metals is an effective method of rendering the metals harmless, provided that immobilization is irreversible. This study focused on the heavy metal immobilization potential associated with the activities of anaerobic bacteria known as the dissimilatory sulfate reducers (Postgate, 1984). The sulfate-reducing bacteria produce sulfide and …

Planning For Basic Needs In India: A Supplement., Monoj Kumar Panda Dr.

Doctoral Theses

Problems of economic development have received a great deal of attention in the last four decades. This has led to the evolution of several development goals like growth, redistribution, poverty alleviation and basic needs satiafac- tion. Initially, development atrategies e eared to were achieve maximum feasible growth rates. It was generally felt that the benefits of growth would spread widely to different sections of the population and in particular would percolate to the lower income groups. Judged by growth in national income, the development efforts have been successful, though to varying ext ent in different countries. But the percola- tion …

Arkansas Soil Fertility Studies 1991, Wayne E. Sabbe

Arkansas Agricultural Experiment Station Research Series

Contained within this publication are progress reports on the specific aspects of the soil fertility program at the University of Arkansas in 1991. In most instances, the reports are not final reports, but they may contain data from several years. Further details on each report can be obtained from the respective project leaders.

Soil Heterogeneity And Its Exploitation By Plants, Robert B. Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this dissertation I first examine the ability of individual plants in the field to garner localized soil nutrients. I then measure actual soil variability around perennial plants and use various statistics to quantify the scale and degree of that variability.

Soil patches on opposite sides of Pseudoroegneria spicata tussocks were treated with distilled water or a nutrient solution containing N, P, or K in three field experiments. When P was augmented in the enriched soil patches, rates of P uptake increased significantly for roots from enriched patches compared with roots in control patches. Rates of ammonium and potassium uptake …

Problems With Management Of A Native Predator On A Threatened Species: Raven Predation On Desert Tortoises, William I. Boarman

Vertebrate Pest Conference Proceedings: 15th (1992)

Common ravens (Corvus corax) are a major predator on the threatened desert tortoise (Gopherus [=Xerobates] agassizii). Large numbers of juvenile tortoise shells have been found beneath known raven nests and perches; many shells that show evidence consistent with raven predation have been found sporadically throughout the range of the tortoise; significant proportional decreases in juvenile size/age class distributions have been identified; and people have observed ravens killing, carrying, and consuming juveniles. In 1988 the U. S. Bureau of Land Management initiated a process to evaluate, design, and implement a program to reduce raven predation …

Nonlethal Repellents: The Development Of Cost-Effective, Practical Solutions To Agricultural And Industrial Problems, J. Russell Mason, Larry Clark

Vertebrate Pest Conference Proceedings: 15th (1992)

Repellents substances and devices cause pest species to avoid otherwise attractive or palatable materials. For birds, repellents can be visual, auditory, pyrotechnic, tactile, chemosensory, physiologic, or physical. Here, we consider chemical agents only. Few substances are registered with the U.S. Environmental Protection Agency (EPA), and thus legally available for use. This lack of available bird repellent technology reflects the small demonstrable economic impact of many agricultural bird damage problems. Accurate information about damage and market size is virtually nonexistent, and private companies are reluctant to invest resources in the unknown. To successfully commercialize new repellents, clearly lucrative markets must be …

Calciferols And Bait Shyness In The Laboratory Rat, C.V. Prescott, Vusa El-Amin, R.H. Smith

Vertebrate Pest Conference Proceedings: 15th (1992)

Rodenticides with delayed action are generally more effective than fast-acting compounds because of the phenomenon of bait shyness. Calciferols have a stop-feed effect quite soon after dosing, and physiological effects are measurable within one day of dosing. We investigated whether bait shyness might result from these fairly rapid effects in the laboratory rat. We found evidence of bait shyness following recovery from sub-lethal dosing with two forms of calciferol. Use of intubation as well as feeding showed that the response was to the bait carrier rather than to detection of calciferols per se.