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Full-Text Articles in Physical Sciences and Mathematics

The Effects Of Two Polycyclic Aromatic Hydrocarbons Benzo[A]Pyrene And Naphthalene On Reproductive Success Embryological Development Larval Physiology And Mortality Of The Mud Crab Rhithropanopeus Harisii (Gould), Gregory V. White Oct 1990

The Effects Of Two Polycyclic Aromatic Hydrocarbons Benzo[A]Pyrene And Naphthalene On Reproductive Success Embryological Development Larval Physiology And Mortality Of The Mud Crab Rhithropanopeus Harisii (Gould), Gregory V. White

OES Theses and Dissertations

Polycyclic aromatic hydrocarbons (PAHs) such as naphthalene (Nap) and benzo[a]pyrene (B[a]P) are common in the water column and sediments of estuarine and coastal areas. The mud crab Rhithropanopeus harrisii was exposed to varying concentrations of Nap or B[a]P to determine the effects on reproductive success, embryological development, larval physiology and mortality. Nap and B[a]P decreased hatching success and prolonged embryological development. Both pollutants produced high abnormality frequencies for egg exposed larvae. Molt frequency and respiratory rates of larvae from non-exposed eggs were more chronically affected by these pollutants than were egg exposed larvae. The EC50 concentrations were determined for …


A Descriptive Study Of Range Livestock Operations In The Somali Central Rangelands, Abdinasir M. Abdulle May 1990

A Descriptive Study Of Range Livestock Operations In The Somali Central Rangelands, Abdinasir M. Abdulle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Information on livestock operations, particularly what kind of livestock operations are practiced in the Somali central rangelands, and how these operations differ for different herders in different vegetation types and farming systems, could serve as a major tool in making management decisions. This study provides a detailed description of range livestock operations in the Somali Central Rangelands. It also answers some important management questions.

Range livestock operations were inventoried through personal interviews with the owners and herders. Data are supplemented by previous nation-wide and regional survey statistics. Herd productivity data which include herd structures, age, age-related sales, slaughters, gifts, and …


The Effect Of Seasonal Cattle Grazing On California Bighorn Sheep Habitat Use, Melanie J. Steinkamp May 1990

The Effect Of Seasonal Cattle Grazing On California Bighorn Sheep Habitat Use, Melanie J. Steinkamp

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of seasonal cattle grazing on a newly reintroduced population of California bighorn sheep (Ovis canadensis californiana) in Big Cottonwood Canyon, Idaho, was studied. The hypothesis that bighorn sheep avoid cattle was tested. The issue of avoidance between bighorn sheep and livestock is arguable. Some studies have found that bighorn sheep avoid cattle while others have found no response of bighorn sheep to cattle.

Evidence was found to document the avoidance of cattle by bighorn sheep. The size of the bighorn's home range and core area decreased with the movement of cattle into areas of high bighorn …


The Effects Of Disease, Prey Fluctuation, And Clear-Cutting On American Marten In Newfoundland, Canada, Richard J. Fredrickson May 1990

The Effects Of Disease, Prey Fluctuation, And Clear-Cutting On American Marten In Newfoundland, Canada, Richard J. Fredrickson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Individual variation in survival and behavior of American marten (Martes americana) was studied in relation to disease, prey fluctuation, and clear-cutting from 10 January 1986 through 20 August 1987 in Newfoundland, Canada. Thirty-seven of forty marten captured on the study area were telemetered and monitored for part or all of the study.

Marten mortality was concentrated in two intervals, fall 1986 and late winter 1987. Mortality during fall 1986 was attributable to encephalitis, while marten deaths during late winter 1987 resulted from predation and starvation attributable to the prey decline. Nonsuppurative encephalitis was first detected 7 October 1986; …


Fisheries Development And Its Role For Alleviating Nutritional Deficiency In Mauritania, Dia Mamadou Abdoul Jan 1990

Fisheries Development And Its Role For Alleviating Nutritional Deficiency In Mauritania, Dia Mamadou Abdoul

Theses and Major Papers

Security of food supply is one of the greatest problems that Mauritania continues to face. Fisheries development, both artisanal and industrial, has the potential of providing an increased and reliable low-cost source of animal protein and it could also help to alleviate the problems of the agricultural sector. The main focus of this paper will be upon fisheries development in Mauritania and how it may contribute to alleviating malnutrition. The examination of Mauritania's fisheries policy, the significance of the political and economic context in which fishing policy was formulated, the effects that these different policies have on Mauritania's overall development …


Conflict Of Use At Moonstone Beach (R.I.); Nude Bathing At A National Wildlife Refuge, Marielena Scanlon Jan 1990

Conflict Of Use At Moonstone Beach (R.I.); Nude Bathing At A National Wildlife Refuge, Marielena Scanlon

Theses and Major Papers

Nude bathing in the coastal zone has become a challenging issue for coastal managers. This thesis focuses on the conflicts involving public uses of a beach on a national wildlife refuge. The beach is nesting habitat for the piping plover (Charadrius melodus), a species listed as threatened on the federal Endangered Species List. The beach has also been traditionally used by nude bathers. The study consists of six parts: a brief natural history of the piping plover; management problems of federal refuges; the history and political conflicts relevant to the recreational use of this beach; an analysis of the users …


Fishermen, Dealers And The Auction System: A Case Study Of Rabo De Peixe, Sao Miguel, Azores, Carlos Teixeira Jan 1990

Fishermen, Dealers And The Auction System: A Case Study Of Rabo De Peixe, Sao Miguel, Azores, Carlos Teixeira

Theses and Major Papers

This thesis presents an examination of the fish auction system in the Azores and three New England ports; Boston, New Bedford and Portland. On the island of Sao Miguel, the village of Rabo de Peixe was selected as a case study where a survey of local fishermen and dealers was conducted. Data obtained through interviews provided some insights into the socio-economic status of local fishermen and how they perceive infrastructure improvements, government support and changes in the auction system. Most importantly, an attempt is made in this study to compare the organizational and administrative aspects of U.S. auction systems in …


The Canadian-American Dispute Over Dixon Entrance, Mary Kathleen Morrissey Jan 1990

The Canadian-American Dispute Over Dixon Entrance, Mary Kathleen Morrissey

Theses and Major Papers

The body of water between the southern tip of Alaska's panhandle and British Columbia's Queen Charlotte islands, known as Dixon Entrance, is one of four external maritime boundaries between the United States and Canada. This particular boundary has been an area of dispute ever since it was established and settlement does not appear to be imminent. yet, this dispute continues to create poor management of fish stocks, trade disruption, feelings of frustration among fishermen of both nations, and in general, it remains a thorn in the side of United States-Canadian relations. In this paper I intend to review the history …


Population Dynamics Of Young-Of-The-Year Striped Bass, Morone Saxatilis, Populations, Based On Daily Otolith Increments, Lisa L. Kline Jan 1990

Population Dynamics Of Young-Of-The-Year Striped Bass, Morone Saxatilis, Populations, Based On Daily Otolith Increments, Lisa L. Kline

Dissertations, Theses, and Masters Projects

Validation of daily increment deposition in otoliths of juvenile striped bass up to 80 days of age was provided through sequential sacrifice of known age hatchery-reared fish in 1987 and 1989, and through tetracycline marking of otoliths of cage-cultured striped bass in 1989. Ages of fish between 80-110 days old were consistently underestimated by 1-3 growth increments. Known age juvenile striped bass were raised in the laboratory in 1989 under controlled environmental conditions. These experiments provided evidence of an endogenous circadian rhythm controlling daily increment deposition in juvenile striped bass otoliths. Juvenile striped bass were collected in the 4 Virginia …