Aquaculture and Fisheries Commons^™

Fisheries Report No 71 - An Investigation Of The Mortality Of The Pearl Oyster, Pinctada Maxima, In Western Australia, Rand Dybdahl, David A. Pass

Fisheries Research Reports

A three year investigation into the cause of abnormally high mortality rates of the pearl oyster, Pinctada maxima, on the cultured pearl industry's lease sites in the North West of Western Australia was completed on 30 June 71983. The objective of this study was to determine environmental, physiological and pathological factors predisposing farm oysters to excessive Levels of mortality and, if possible, make recommendations to alleviate this problem.

As mass mortalities may have complex causes, complementary field and laboratory studies were instigated. The culture industry's method of collection, transportation and farm husbandry were examined. Environmental parameters were monitored. Various empirical …

A Proposal To Fertilize The Overton Arm And Gregg Basin Areas Of Lake Mead, Larry J. Paulson

Publications (WR)

Several limnological studies have been conducted in Lake Mead during the past decade. The recent studies clearly show that most of Lake Mead is deficient in nutrients, especially phosphorus, and very low in productivity. The reservoir-wide average total phosphorus concentration for 1981 - 1982 was only 9 mg/m³. This is below levels found In most oligotrophic lakes and reservoirs. Algal biomass, as measured by chlorophyll-a, averaged only 1.5 mg/m³. That also places Lake Mead in the oligotrophic range. Transparency, as measured by a Secchi disc, averaged 9-5 m in Lake Mead during 1981-1982. That far exceeds …

The Phillipine Extended Jurisdiction: Its Cost And Benefits To Fishery Industry, Ricardo R. Federizon

Marine Affairs Theses and Major Papers

The Philippines is one of the countries that has its significant relations to fisheries economically and culturally. The coastal waters of the Philippines support over a million fishermen whose only source of income is fishing that does not go far off-shore. Due to population pressure and increased demand for fish as a basic food supply and as a source of foreign revenue income, more and more fishermen fish at the waters that carry a limited resource. As a result, overfishing persists that has a social and economic implication. Conflicts arise among the fishermen. Management measures are not implemented successfully because …

Toxicological Studies On Aquatic Contaminants Originating From Coal Production And Utilization: The Induction Of Tolerance To Silver In Laboratory Populations Of Fish And The Chronic Toxicity Of Nickel To Fish Early Life Stages, Wesley J. Birge, Jeffrey A. Black, James F. Hobson, Albert G. Westerman

KWRRI Research Reports

Aquatic toxicity studies were performed on two important coal-derived contaminants, silver and nickel. Silver was investigated with regard to metal-induced tolerance in laboratory populations of the fathead minnow (Pimephales promelas). Fish were exposed to acute silver concentrations following acclimation to sublethal exposures of this metal. Based on median lethal times (LT50), animals which had received 14 days prior exposure to 1.5 and 15 μg Ag/L were three to four times more resistant to silver than were previously unexposed organisms. This metal-induced resistance was not a sustained response. After organisms which had been acclimated to 15 μg/L had been transferred to …

The Spatial And Temporal Distribution Of The Larvae Of Sympatric Pagurid Hermit Crabs (Decapoda, Anomura) In Virginian Estaurine And Coastal Waters, Philip Wesley Sadler

OES Theses and Dissertations

Thirteen stations were occupied at two - week intervals from May through September 1980 within the York River, lower Chesapeake Bay depths encompassing the entire water column.

Three species of pagurids were identified: Pagurus longicarpus, P. pollicaris, and P. annulipes. The larvae of P. annulipes had not been previously identified from Virginian waters. The shapes of the antennae of P. pollicaris and P. annulipes weredistinctive, allowing rapid identification of these larvae. The shapes of the uropods were found to be useful in distinguishingthe glaucothoe· of P. longicarpus from P. annulipes. The larvae of these species …

Seasonal And Spatial Heterogeneity In The Limnetic Zooplankton Community Of Lake Mead, Gene Robert Wilde

Publications (WR)

Zooplankton samples collected from throughout Lake Mead, in 1981-1982, demonstrate the presence of a statistically significant seasonal and spatial heterogeneity in zooplankton densities. Seasonally, the major zooplankton groups were most abundant in the spring and fall, coincident with maxima in chlorophyll-a concentrations. Successions among the various rotifers, cladocerans and copepods present in the reservoir were influenced by food availability, diapause, predation by planktivorous fish and, possibly, water temperatures. Spatial heterogeneity in zooplankton densities was unrelated to water temperature, pH, conductivity and dissolved oxygen concentrations, but was related to the abundance of phytoplankton (chlorophyll-a concentrations) and fish. Statistical analyses indicate that …

An Intraseason Forecasting System For Commercial Marine Fisheries, Erik J. Barth

OES Theses and Dissertations

The reliability of an intraseason yield estimation technique which is commonly used by Pacific salmon harvest managers is evaluated for applicability to a variety of commercial finfish and crustacean fisheries. The estimation technique is known as the average timing or the average performance model. The method is not easily related to standard statistical models, but does show some similarity to both a single parameter linear regression model and the ratio estimator of sampling theory. A comparison of these models, a two parameter linear model, and a regression estimator is made to determine if the precision of forecasts of performance can …

An Examination Of The Variability Of Migratory Timing Statistics Estimated From Catch And Effort Observations, Arthur J. Butt

OES Theses and Dissertations

The estimate of the mean arrival time based on catch or CPUE of fishes migrating into a fixed harvest area is a function of the number of days fished. Simulation studies using chinook salmon catch and effort data from the Yukon River delta, Alaska indicate that fishing effort concentrated at the tails of the migratory distribution which would tend to erroneously weigh the estimated mean arrival time in the direction of the sample, away from the true mean, is only a significant problem when the number of days open to fishing is small, covering less than 12% of the total …

Determinants For The Timing Of Escapement From The Sockeye Salmon Fishery Of The Copper River, Alaska: A Simulation Model, Howard A. Schaller

OES Theses and Dissertations

A model to estimate determinants for migratory timing of catch and escapement in a terminal salmon fishery is presented. A method was developed to estimate average seasonal migration rates of salmon through a harvest area from catch and escapement data. The time series for the total population of Copper River sockeye salmon (Oncorhynchus nerka) was reconstructed in the reference frame of the commercial harvest area from catch and escapement data.

The catchability coefficients (q), derived from the reconstructed populations were found to vary within season and between seasons. The relation between q and effort was attributed to a …

Timing Of The Blue Crab Fisheries Of Virginia And Its Application To Harvest Management, J. Dale Shively

OES Theses and Dissertations

The timing of a fishery is a quantitative expression of the composite behaviors of harvesters, markets, animals and climatic events. A quantitative description of the timing of the blue crab (Callinectes sapidus) fisheries of Virginia was established using the time density model of Mundy (1979). Blue crab catch statistics supplied by the National Marine Fisheries Service and the Virginia Marine Resource Commission were divided into two fisheries based on gear type; the summer and winter fisheries. Average performance curves were then constructed using average cumulative proportions of catch. Annual yield estimates were also made and timing in five …

A Description And Analysis Of The Timing Of Virginia's Weakfish Fishery, Bruce William Hill

OES Theses and Dissertations

The seasonality of Virginia's weakfish fishery is quantitatively defined by providing a mean time of catch and variance of catch for the years 1960 - 1981. On the average. the central half of the population is available for harvest from mid-May through September in all of Virginia's waters and the mean date of harvest is July 20th • The 22 year average variance of catch for Virginia's waters is 3.97. In Virginia's Chesapeake Bay tributaries the mean date of harvest is July 17th and the 22 year average variance of catch is 2.50. There is evidence for an inverse relationship …

Fishery Harbor Development: A Case Study Of A Connecticut Coastal Community, Stonington, Connecticut, James L. Wallace

Marine Affairs Theses and Major Papers

This study was undertaken to investigate the problems and procedures encountered in the development of fishery harbors in Connecticut. Harbor facilities along the coast are in great disrepair or have been completely eliminated to allow for more profitable coastal uses. In addition, conflict between recreational and commercial fishermen for existing space has created a shortage of commercial harbor facilities. Because of this need, state and local officials have begun to investigate viable harbor development alternatives for Connecticut.

By-Catch: Over The Side Discards, An Assessment And An Alternative, Alan R. Bunn

Marine Affairs Theses and Major Papers

The incidental capture and resultant mortality of numerous fin-fish and other species of marine organisms by non-selective types of fishing gear constitute a major waste of the various fishery resources. The magnitude of the discarded by-catch and its effects upon the major fisheries is examined. Specific gear types contributing to the problem will be identified. The Gulf of Mexico shrimp fishery of the U.S., which annually catches over a billion pounds of unwanted fin-fish or “trash-fish” will be examined and an evaluation of the continuing development of selective shrimp trawling gear specifically designed to reduce the incidental capture of sea …

The Effects Of Regulation On Aquaculture Development, Derek S. Busby

Marine Affairs Theses and Major Papers

A comparative study of the regulatory frameworks surrounding aquaculture in the states of Florida, Mississippi, and Rhode Island is conducted beginning with a generalized study of basic legal premises of aquaculture-related law common to each state. This is followed by a detailed study of the statutory authority for aquaculture regulation and the agencies which control aquaculture activities in each state. In conjunction with the law analysis an Index of Specialization (ISP) study is conducted for each state to determine a relative ranking of diversity of crop production relative to each state’s overall aquaculture production.

Marine Resources: The Presentation Of A Business Plan, K. Scott Colby

Marine Affairs Theses and Major Papers

The once questionable technology of hatchery production has become routine and, with the recent development of up-welling techniques, is more effective and efficient. The supply of natural shellfish and fishery stocks is on the decline and this trend is expected to continue. Aquaculture has been the solution to this problem in many European countries and the United States is currently attempting to remove domestic obstacles through its National Aquaculture Plan. The proprietor has experience in the production of various marine invertebrates and has designed, built and operated a producing shellfish hatchery. By using a unique up-welling juvenile culture system a …

Fisheries Report No 66 - The Fishery For Perth Herring, Nematalosa Vlaminghi (Munro), C F. Chubb, N. G. Hall, R C.J. Lenanton, I. C. Potter

Fisheries Research Reports

Perth herring fishery over the last 30 years have been examined. While there are pockets of catches between Broome and Bunbury, those from the Swan Estuary and nearby inshore marine waters make by far the most important contribution to the fishery. In the Swan Estuary, the catches started rising in the 1950s in response to a demand by the rock lobster industry for bait and reached peak values in the late 1960s and early 1970s. Data are provided which demonstrate that catch per boat is a good index of catch per unit effort (CPUE) in the period since 1967 when …

Fisheries Report No. 65 - The Amateur Fishery For Marron (Cherax Tenuimanus) In Western Australia - Summary Of Logbook Data 1971-83, N. Morrissy, C. Fellows, N. Caputi

Fisheries Research Reports

The large, native crayfish called marron, Cherax tenuimanus, supports an extensive recreational fishery in the southwest of Western Australia. This report examines annual catch and effort statistics gathered from a Logbook programme, initiated in the 1971/72 season and supplemented by an end of season telephone survey from 1977. Logbook data gave estimates of relative abundance, but were too biased for projection to total catch and effort for the fishery, while telephone surveys gave unbiased estimates of total annual fishing effort (trips)l.

Relative abundance showed a significant decline in the major rivers and the most popular dam (Wellington) over the monitoring …

Fisheries Report No 60 - Amateur Net Fishing Survey Of Two Western Australian South Coast Estuaries In January 1981, D. I. Heald

Fisheries Research Reports

Following the return of the administration of fishing activities in Wellstead estuary and Beaufort Inlet to the Western Australian Government in October 1980, a survey of the amateur net fishing in these two estuaries was undertaken in January 1987, The purpose of the survey was to document usage, species catches and size composition of fish caught in respect of mesh size used and the success rate of amateur net fishermen as compared to their expectation. At the time of the survey, Wellstead estuary had been closed to the sea for 13 months and Beaufort Inlet for 27 months and the …

Fisheries Report No 63 - Assessment Of Artificial Feeds For Battery Culture Of A Freshwater Crayfish, Marron (Cherax Tenuimanus) (Decapoda: Parastacidae), Dr N. Morrissy

Fisheries Research Reports

Performance of juvenile crayfish, 0.1-5 g, on a variety of commercial crustacean feeds was tested under conditions of individual housing ("battery culture"), where sources of additional feed were minimized (detritus), or eliminated (cannibalism) Survival was close, or equal, to 100% over 50 day test periods, a reflection of optimal battery conditions rather than feeding, since survival over 100 days for an unfed (control} group was also 100%. No ecdysiad mortality, or trauma, occurred with crayfish, up to 10g, in compartments of area 75 cm. Growth performance in tests was rated by separate ratios for ecdysial increment and frequency, relative to …

Fisheries Report No 64 - The Western Rock Lobster Fishery 1977 - 1978, R. S. Brown, E H. Barker

Fisheries Research Reports

The fishery for the western rock lobster Panulirus cygnus is one of the most important single fisheries in Australia and an important export earner for the State. The fishery is governed by a complex set of regulations which have been reviewed by Bowen (1971) and which are designed to limit the total fishing effort to acceptable levels and to enforce a legal minimum size. It is thus important to constantly monitor the state of the fishery both to ensure that the effort is remaining within the accepted limits and that the regulations are adequately performing their function of maintaining reasonably …

Fisheries Report No 67 - The Western Rock Lobster Fishery 1978 - 1979, R. S. Brown, E H. Barker

Fisheries Research Reports

The fishery for the western rock lobster Panulirus cygnus is one of the most important single fisheries in Australia and an important export earner for the State. Western Australia produced a record 11 388 tons in 1978/79, out of a total Australian catch of rock lobster of 15 400 tons. The fishery is governed by a complex set of regulations which have been reviewed by Bowen (1971) and Hancock (1981) and which are designed to limit the total fishing effort to acceptable levels and to enforce a legal minimum size. It is thus important to constantly monitor the state of …

Fisheries Report No 62 - The Commercial Fisheries Of Temperate Western Australian Estuaries: Early Settlement To 1975, R C.J. Lenanton

Fisheries Research Reports

This report provides a quantitative description of the commercial estuarine fisheries of temperate Western Australia. An account is given of the Long series of historical events which influenced the development of the fisheries and led to their current status. All available catch and effort data covering the years 1898 - 1975 are presented. The use of this long series of historical catch and effort data as an aid to the management of the estuarine fisheries resources is discussed. It is emphasised that interpretations of these data cannot be undertaken effectively without a knowledge of factors such as Life history strategies, …

Factors Affecting Reproductive Success Of Bonytail Chubs And Razorback Suckers In Lake Mohave, Michael A. Bozek, Larry J. Paulson, James E. Deacon, U.S. Department Of Interior, Fish And Wildlife Service

Publications (WR)

Razorback suckers (Xyrauchen texanus) and bonytail chubs (Gila elegans) were once widespread throughout the Colorado River system. The ranges and populations of these native species and others have declined in the past 50 years. Bonytail chubs appear to be extremely rare and possibly nearing extinction in the Upper Colorado River Basin. The razorback sucker is widely distributed in the upper river but is considered rare throughout most of that range and is also rare in the Grand Canyon. Razorback suckers are abundant only in a few habitats in the upper river. They congregate and spawn over …

State Of The Fisheries Report 1983, Department Of Fisheries And Wildlife, Western Australia

Status Reports of the Fisheries and Aquatic Resources

Western Australia continues to be one of the leading States in Australia. The total gross value of fish, crustaceans and molluscs for 1982/83 was $126 million (Table 1) to which may be added the value of the pearl culture industry resulting in a total value of approximately $140 million.

The Joint Venture Controversy: A Short-Term Solution For A Long-Term Fisheries Policy, Laurie A. Frost

Marine Affairs Theses and Major Papers

This paper will examine the development of joint ventures under the FCMA, the legislative and regulatory measures designed to control these ventures and the procedures for establishing a joint venture. More recent developments in joint venture policy will be examined, including the controversy over squid joint ventures on the East Coast, to determine what the objectives are and what current policy is regarding join ventures. The debate between harvesters and processors will be put forth as a way of summarizing the costs and benefits of joint ventures to the industry as a whole.