Open Access. Powered by Scholars. Published by Universities.®

Aquaculture and Fisheries Commons

Open Access. Powered by Scholars. Published by Universities.®

Environmental Sciences

1997

Articles 1 - 17 of 17

Full-Text Articles in Aquaculture and Fisheries

Management Options For Pilbara Demersal Line Fishing, Gaye Looby Nov 1997

Management Options For Pilbara Demersal Line Fishing, Gaye Looby

Fisheries management papers

Fisheries Western Australia licensing arrangements allow all vessels with an unrestircted fishing boat licence ('wetline licence') to take scalefish throughout the State. These arrangements have led to a high level of excess capacity in the licensed 'wetline' fishing fleet to exploit the scalefish resources. The declaration of the Kimberley Interim Line Fishery and forthcoming declaration the Northern Demersal Scalefish Fishery have resolved this problem for the Kimberley waters. However, the high level of excss capacity in the 'wetline' fleet to exploit the waters of the Pilbara remains a problem Preview access and develop a management plan for the Pilbara demersal …


Terrestrial Natural Communities Of Nebraska - Version I, Gerry Steinauer, Steven B. Rolfsmeier Oct 1997

Terrestrial Natural Communities Of Nebraska - Version I, Gerry Steinauer, Steven B. Rolfsmeier

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

The Nebraska Natural Heritage Program has been collecting information and data including published literature, field observations and vegetation plot data over the last 10 years of development of Nebraska’s natural community classification. The classification contains 27 wetland and 36 upland communities including forest, woodland, shrubland, herbaceous, and sparsely vegetated (e.g. rock outcrop) types. The community types were distinguished primarily on plant species composition and to a lesser extent on soils, hydrology and geographic location. The classification contains descriptions of each community type that include dominant species, soils, range, and other ecological information. The classification is designed to be flexible enough …


Abalone Aquaculture In Western Australia. Discussion Paper And Draft Policy Guidelines., Cameron Westaway, Jeff Norriss Oct 1997

Abalone Aquaculture In Western Australia. Discussion Paper And Draft Policy Guidelines., Cameron Westaway, Jeff Norriss

Fisheries management papers

The purposes of this discussion paper is to highlight relevant issues associated with abalone aquaculture development and outline a set of draft policy guidelines. The paper is being disseminated to members of the aquaculture industry, commercial and recreational fishing bodies and the broader community to allow comment.


Issues Affecting Western Australia's Inshore Crab Fishery Blue Swimmer Crab (Portunus Pelagicus) Sand Crab (Ovalipes Australiensis), Cathy Cambell Sep 1997

Issues Affecting Western Australia's Inshore Crab Fishery Blue Swimmer Crab (Portunus Pelagicus) Sand Crab (Ovalipes Australiensis), Cathy Cambell

Fisheries management papers

This paper is designed to inform the general public about the issues and management options for managing the State's blue swimmer and sand crab fishery.


Changes In Reproductive Morphology And Physiology Observed In The Amphipod Crustacean, Melita Nitida Smith, Maintained In The Laboratory On Polluted Estuarine Sediments, John T. Tanacredi Ph.D., B. Borowsky, P. Aitken-Ander Jul 1997

Changes In Reproductive Morphology And Physiology Observed In The Amphipod Crustacean, Melita Nitida Smith, Maintained In The Laboratory On Polluted Estuarine Sediments, John T. Tanacredi Ph.D., B. Borowsky, P. Aitken-Ander

Faculty Works: CERCOM

An earlier study showed that the amphipod crustacean Melita nitida Smith maintained on sediments dosed with waste crankcase oil developed physiological and morphological abnormalities. Most notably, mature females developed abnormal setae along the edges of their brood plates. The present study was conducted to determine whether similar abnormalities might be induced in animals maintained on polluted field sediments containing petroleum by-products among other toxic substances. In the laboratory, heterosexual pairs were maintained on three sediments taken from Jamaica Bay (New York) plus one control sediment and one toxic substratum (Ulva lactuca (L.) thalli). The results mirrored the results of …


Idealwise Algebraic Independence For Elements Of The Completion Of A Local Domain, William Heinzer, Christel Rotthaus, Sylvia Wiegand Jul 1997

Idealwise Algebraic Independence For Elements Of The Completion Of A Local Domain, William Heinzer, Christel Rotthaus, Sylvia Wiegand

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Over the past forty years many examples in commutative algebra have been constructed using the following principle: Let k be a field, let S k[xl Xn]x,xn) be a localized polynomial ring over k, and let a be an ideal in the completion S of S such that the associated prims of a are in the generic formal fiber of S; that is, p N S (0) for each p Ass(S/a):. Then S embeds in S/a, the fraction field Q(S) of S embeds in the fraction ring of S/a, and for certain choices of a, the intersection D Q(S) f3 (S/a) …


Status Of The Major Oyster Diseases In Virginia 1996 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson Mar 1997

Status Of The Major Oyster Diseases In Virginia 1996 A Summary Of The Annual Monitoring Program, Lisa M. Ragone Calvo, Eugene M. Burreson

Reports

No abstract provided.


Identification Of A Fish Host Of The Inflated Heelsplitter Potamilus Inflatus( Bivalvia: Unionidae) With A Description Of Its Glochidium, Kevin J. Roe, Andrew M. Simons, Paul Hartfield Jan 1997

Identification Of A Fish Host Of The Inflated Heelsplitter Potamilus Inflatus( Bivalvia: Unionidae) With A Description Of Its Glochidium, Kevin J. Roe, Andrew M. Simons, Paul Hartfield

Kevin J. Roe

A survey of the fishes of the lack Warrior River was undertaken to determine fish host(s) of the federally threatened inflated heelsplitter, Potamilus inflatus. Seven hundred-twenty individual fishes representing 30 species were examined; mussel glochidia were found on 10 individual fishes representing nine species. Potamilus inflatus glochidia were only found infesting one freshwater drum (Aplodinotus grunniens), which is concordant with previous findings for the genus Potamilus. The morphology of P. inflatus glochidia is described and compared to P. purpuratus.


Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell 1997, Wayne A. Wurtsbaugh, Kirsten L. Gallo Jan 1997

Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell 1997, Wayne A. Wurtsbaugh, Kirsten L. Gallo

Watershed Sciences Faculty Publications

Physical characteristics of lakes are highly interrelated with biological characteristics. We measured and analyzed the physical characteristics of two side canyons in order to better understand differences in productivity between side canyons and the main channel and to provide general information on the characteristics of the lake.


Fertilization Of An Oligotrophic Lake With A Deep Chlorophyll Maximum: Predicting The Effect On Primary Productivity, H. P. Gross, Wayne A. Wurtsbaugh, Phaedra E. Budy, Chris Luecke Jan 1997

Fertilization Of An Oligotrophic Lake With A Deep Chlorophyll Maximum: Predicting The Effect On Primary Productivity, H. P. Gross, Wayne A. Wurtsbaugh, Phaedra E. Budy, Chris Luecke

Watershed Sciences Faculty Publications

We investigated how epilimnetic fertilization would affect chlorophyll levels and light penetration of oligotrophic sockeye salmon (Oncorhynchus nerka) lakes and how the resulting self-shading would affect primary production of the prominent deep chlorophyll maxima (DCM) of the lakes. Epilimnetic nutrient additions to large mesocosms (330 m3) in Redfish Lake, Idaho, increased levels of primary productivity and chlorophyll a but decreased Secchi depths and light available in the metalimnion and hypolimnion. Redfish Lake and other Sawtooth Valley (Idaho) lakes had DCM in which the mean chlorophyll a peaks were 240-1000% of mean epilimnetic chlorophyll a concentrations. The DCM existed at low …


Hydroacoustic Assessment Of Abundance And Diel Distribution Of Sockeye Salmon And Kokanee In The Sawtooth Valley Lakes, Idaho, D. Beauchamp, Chris Luecke, Wayne A. Wurtsbaugh, H. G. Gross, Phaedra E. Budy, S. Spaulding, R. Dilenger, C. P. Gubala Jan 1997

Hydroacoustic Assessment Of Abundance And Diel Distribution Of Sockeye Salmon And Kokanee In The Sawtooth Valley Lakes, Idaho, D. Beauchamp, Chris Luecke, Wayne A. Wurtsbaugh, H. G. Gross, Phaedra E. Budy, S. Spaulding, R. Dilenger, C. P. Gubala

Watershed Sciences Faculty Publications

We used dual-beam hydroacoustics and echo integration techniques, combined with midwater trawling and gillnetting, to assess the abundance and distribution of the endangered Snake River juvenile sockeye salmon and resident kokanee (both Oncorhynchus nerka) in Sawtooth Valley lakes of Idaho during September 1991 and 1992. Abundance of O. nerka varied among the four lakes containing this species (12,500–257,000) and varied between years in Redfish Lake (86,400 in 1994 and 241,000 in 1992) and Alturas Lake (230,000 in 1991 and 257,000 in 1992). In Alturas Lake, where piscivore densities were high and zooplankton densities were low, small acoustic targets (≤18 cm …


Nutrient Limitation Of Oligotrophic Sockeye Salmon Lakes Of Idaho (Usa), Wayne A. Wurtsbaugh, H. P. Gross, Chris Luecke, Phaedra E. Budy Jan 1997

Nutrient Limitation Of Oligotrophic Sockeye Salmon Lakes Of Idaho (Usa), Wayne A. Wurtsbaugh, H. P. Gross, Chris Luecke, Phaedra E. Budy

Watershed Sciences Faculty Publications

"Phytoplankton production in lake ecosystems is frequently controlled by amounts of nitrogen and phosphorus (Smith 1982, Elser et al. 1990), as well as minor- and micro-nutrients (Wurtsbaugh & Horne 1983, Wurtsbaugh 1988, Lovstad & Bjorndalen 1990). Nutrient limitation is often studied to determine which nutrient(s) should be reduced to control lake eutrophication (Schindler 1974(. Conversely, nutrients have been used for decades to stimulate plankton and, subsequently, fish production in aquaculture (Bardach et al. 1972). More recently, lake fertilization has been used to augment salmon runs for commercial exploitation (Hyatt & Stockner 1985, lye et al. 1988), and it has been …


1997 Rapid Ecological Assessment Northern Great Plains Steppe Ecoregion: Western And Central South Dakota, Northwestern Nebraska, Eastern Wyoming, A Final Report, Terri Hildebrand Jan 1997

1997 Rapid Ecological Assessment Northern Great Plains Steppe Ecoregion: Western And Central South Dakota, Northwestern Nebraska, Eastern Wyoming, A Final Report, Terri Hildebrand

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

In an effort to gain a more complete understanding of existing vegetative communities of the Northern Great Plains Steppe Ecoregion, rapid ecological assessment was undertaken throughout the ecoregion during the field season of 1997. Field office personnel of The Nature Conservancy and private contractors evaluated previously delineated regions in accordance with methodology determined in May of 1997. The following document presents results of the rapid ecological assessments performed by Hildebrand Contracting. The purpose of this document is to provide The Nature Conservancy with information to help determine the vegetative features of regions sampled. The specific areas and boundaries for evaluation …


Saltwater Angling And Its Economic Importance To Virginia, James Kirkley, David Kerstetter Jan 1997

Saltwater Angling And Its Economic Importance To Virginia, James Kirkley, David Kerstetter

Reports

No abstract provided.


Virginia Game Fish Tagging Program Annual Report 1996, Cm Bain Iii, John A. Lucy Jan 1997

Virginia Game Fish Tagging Program Annual Report 1996, Cm Bain Iii, John A. Lucy

Reports

The Virginia Game Fish Tagging Program (VGFfP), a cooperative project of the Virginia Marine Resources Commission and the Virginia Institute of Marine Science (VIMS), enjoyed its second full year of operation in 1996. Participation in the project, which is funded with revenues generated by Virginia's saltwater recreational fishing license, nearly doubled with 127 anglers volunteering as taggers compared to 64 in 1995.


Virginia's Commercial Fishing Industry: Its Economic Performance And Contributions, James Kirkley Jan 1997

Virginia's Commercial Fishing Industry: Its Economic Performance And Contributions, James Kirkley

Reports

No abstract provided.


Finfish Aquaculture In Western Australia, David Berry Jan 1997

Finfish Aquaculture In Western Australia, David Berry

Journal of the Department of Agriculture, Western Australia, Series 4

David Berry surveys fish farming from Broome to Williams, on off shore reefs and in farm dams, for barramundi, silver perch and black bream, trout and tuna.