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

Marine Biology Commons™

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

Animal Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 931 - 960 of 1237

Full-Text Articles in Marine Biology

Fisheries Occasional Publication No. 6 - Anglers Guide To Assessing Reproductive Stage In Fish, Kim Smith, Mike Mackie, Department Of Fisheries Western Australia Apr 2004

Fisheries Occasional Publication No. 6 - Anglers Guide To Assessing Reproductive Stage In Fish, Kim Smith, Mike Mackie, Department Of Fisheries Western Australia

Fisheries Occasional Publications

What is a gonad?

"Gonad" is a general term for a reproductive organ, and is used to describe both ovaries and testes. In male and female fish, the gonad is an elongated organ lying along the upper wall of the gut cavity (i.e. running immediately under the vertebral column). The gonad gonad has 2 lobes. Both lobes are attached to the body near the anus and extend forward inside the gut cavity.

As fish gonads ripen, they become larger, heavier and change colour. Immature and undeveloped adult gonads are very small, strap-like in shape, pinkish in colour and translucent (i.e. …


Cheloniidae (Marine Turtle) Nest Predation, John Woolard, Richard M. Engeman, Henry T. Smith, John Griner Feb 2004

Cheloniidae (Marine Turtle) Nest Predation, John Woolard, Richard M. Engeman, Henry T. Smith, John Griner

United States Department of Agriculture Wildlife Services: Staff Publications

On 19 June 2003 at 0217 h, an opossum (Didelphis virginiana) was observed for 10 min while digging into a marine turtle nest and eating 4 eggs on the beach at St. Lucie Inlet Preserve State Park (SLIPSP) on Jupiter Island, Florida. The predation event was observed using night vision equipment as part of nightly patrols to protect turtle nests from raccoon (Procyon lotor) and armadillo (Dasypus noverncinctus) predation during the nesting season. After verification of an ongoing predation event, the opossum was euthanized and removed. Prior to implementing predator removal on this beach, …


Use Of An Artificial Pond And Marshes By Amphibians And Reptiles In West Virginia, Vanessa A. Dozeman Jan 2004

Use Of An Artificial Pond And Marshes By Amphibians And Reptiles In West Virginia, Vanessa A. Dozeman

Theses, Dissertations and Capstones

A farm pond approximately 40 years old located in Wayne County, West Virginia was studied to determine the ingress and egress of amphibians and reptiles. In addition to the pond, 2 small marshes were also examined. The study extended from February 2003 to November 2003. The pond is approximately 36 m long and 38 m wide and is located on a south-facing hillside at 202 m in elevation. A drift fence composed of landscaping cloth was constructed to completely encircle the site. At every 5.15 m, funnel traps were positioned on both sides of the fence. Traps were checked daily …


Age And Growth Of Scotia Sea Icefish, Chaenocephalus Aceratus, From The South Shetland Islands, M. La Mesa, J. Ashford, E. Larson, M. Vacchi Jan 2004

Age And Growth Of Scotia Sea Icefish, Chaenocephalus Aceratus, From The South Shetland Islands, M. La Mesa, J. Ashford, E. Larson, M. Vacchi

OES Faculty Publications

Samples of Chaenocephalus aceratus (Lönnberg) were collected during a trawl survey carried out around the South Shetland Islands in January–February 2002. Fish were caught by commercial bottom trawl fishing down to 500 m depth, using a stratified randomized sampling design. As observed in other recent surveys within the same area, C. aceratus represented one of the predominant species. Overall, 357 specimens ranging from 13 and 67 cm (TL) were selected for the present study. Ages were estimated by counting annuli present in the sagittal otoliths, exposed by grinding and polishing along their sagittal plane. To estimate the precision of age …


Endocrine-Disrupting Effects Of Cattle Feedlot Effluent On An Aquatic Sentinel Species, The Fathead Minnow, Edward Orlando, Alan Kolok, Gerry Binzcick, Jennifer Gates, Megan Horton, Christy Lambright, L. Earl Gray Jr., Ana M. Soto, Louis J. Guilette Jan 2004

Endocrine-Disrupting Effects Of Cattle Feedlot Effluent On An Aquatic Sentinel Species, The Fathead Minnow, Edward Orlando, Alan Kolok, Gerry Binzcick, Jennifer Gates, Megan Horton, Christy Lambright, L. Earl Gray Jr., Ana M. Soto, Louis J. Guilette

Biology Faculty Publications

Over the last decade, research has examined the endocrine-disrupting action of various environmental pollutants, including hormones, pharmaceuticals, and surfactants, in sewage treatment plant effluent. Responding to the growth of concentrated animal feeding operations (CAFOs) and the pollutants present in their wastewater (e.g., nutrients, pharmaceuticals, and hormones), the U.S. Environmental Protection Agency developed a new rule that tightens the regulation of CAFOs. In this study, we collected wild fathead minnows (Pimephales promelas) exposed to feedlot effluent (FLE) and observed significant alterations in their reproductive biology. Male fish were demasculinized (having lower testicular testosterone synthesis, altered head morphometrics, and smaller …


A Modelling Study Of The Influence Of Environment And Food Supply On Survival Of Crassostrea Gigas Larvae, Eileen E. Hofmann, Eric N. Powell, Eleanor A. Bochenek, John M. Klinck Jan 2004

A Modelling Study Of The Influence Of Environment And Food Supply On Survival Of Crassostrea Gigas Larvae, Eileen E. Hofmann, Eric N. Powell, Eleanor A. Bochenek, John M. Klinck

CCPO Publications

A biochemically based model was developed to simulate the growth, development, and metamorphosis of larvae of the Pacific oyster (Crassostrea gigas). The unique characteristics of the model are that it: (1) defines larvae in terms of their protein, neutral lipid, polar lipid, carbohydrate, and ash content; (2) tracks weight separately from length to follow larval condition; and (3) includes genetic variation in growth efficiency and egg quality to better simulate cohort population dynamics. The model includes parameterizations for filtration, ingestion, and respiration, which determine larval growth rate, and processes controlling larval mortality and metamorphosis. Changes in larval tissue …


Lagrangian Modelling Studies Of Antarctic Krill (Euphausia Superba) Swarm Formation, Eileen E. Hofmann, A. G. Edward Haskell, John M. Klinck, Cathy M. Lascara Jan 2004

Lagrangian Modelling Studies Of Antarctic Krill (Euphausia Superba) Swarm Formation, Eileen E. Hofmann, A. G. Edward Haskell, John M. Klinck, Cathy M. Lascara

CCPO Publications

A two-dimensional Lagrangian particle model was developed to examine the spatial distribution of Antarctic krill (Euphausia superba). The time-dependent location of particles, which represent krill individuals, is determined by random diffusion, foraging activity, and movement induced by the presence of neighbours. Foraging activity is based on prescribed food conditions and is such that krill swim slower and turn more frequently in areas of high food concentration. The presence or absence of neighbours either disperses krill, if the local concentrations become too dense, or coalesces krill, if concentrations become too dilute, respectively. Predation on krill is included and affects …


A New Pathogenic Virus In The Caribbean Spiny Lobster Panulirus Argus From The Florida Keys, Jeffrey D. Shields, Donald C. Behringer Jr. Jan 2004

A New Pathogenic Virus In The Caribbean Spiny Lobster Panulirus Argus From The Florida Keys, Jeffrey D. Shields, Donald C. Behringer Jr.

Biological Sciences Faculty Publications

A pathogenic virus was diagnosed from juvenile Caribbean spiny lobsters Panulirus argus from the Florida Keys. Moribund lobsters had characteristically milky hemolymph that did not clot. Altered hyalinocytes and semigranulocytes, but not granulocytes, were observed with light microscopy. Infected hemocytes had emarginated, condensed chromatin, hypertrophied nuclei and faint eosinophilic Cowdry-type-A inclusions. In some cases, infected cells were observed in soft connective tissues. With electron microscopy, unenveloped, nonoccluded, icosahedral virions (182 +/- 9 nm SD) were diffusely spread around the inner periphery of the nuclear envelope. Virions also occurred in loose aggregates in the cytoplasm or were free in the hemolymph. …


Characterization Of Association Patterns Of Coastal Migratory Bottlenose Dolphins, Tursiops Truncatus, In The Nearshore Waters Of Virginia Beach, Virginia, Holly Fearnbach Jan 2004

Characterization Of Association Patterns Of Coastal Migratory Bottlenose Dolphins, Tursiops Truncatus, In The Nearshore Waters Of Virginia Beach, Virginia, Holly Fearnbach

Biological Sciences Theses & Dissertations

Bottlenose dolphins, Tursiops truncatus, commonly occur in fission-fusion social systems. For this study, I analyzed photo-identification data from 1994 to 1999 to describe association patterns of bottlenose dolphins in the nearshore waters of Virginia Beach, Virginia. Bottlenose dolphins are present seasonally (late April until early November) in these waters and individuals are considered to be members of the North Atlantic coastal migratory stock. I selected 78 individuals for detailed analyses from the 972 dolphins identified in the study area. Those chosen as “select” dolphins had been sighted at least five times in three of the six study years; all …


Predicting Fish Species Diversity In Lotic Freshwaters Of Greece, Eugene G. Maurakis, David V. Grimes Oct 2003

Predicting Fish Species Diversity In Lotic Freshwaters Of Greece, Eugene G. Maurakis, David V. Grimes

Virginia Journal of Science

Objectives were to test the hypothesis that stream order and stream width alone account for species diversity in drainages of Greece, and to create a mathematical model that predicts fish diversity in small and medium sized freshwater streams in the southern Balkan Peninsula in accord with the stream classification system proposed by the European Environmental Agency (EEA). Thirty-seven species of fishes in 12 families (Petromyzontidae, Anguillidae, Cyprinidae, Moronidae, Centrarchidae, and Blenniidae) were collected in five stream orders (1-5) from 19 river drainages in Greece in 1993 and from 2000-2002. Numbers of species were significantly correlated with stream order (+), width …


Identification Key To Fishes In Fresh Waters Of Greece, Eugene G. Maurakis, Panos S. Economidis Oct 2003

Identification Key To Fishes In Fresh Waters Of Greece, Eugene G. Maurakis, Panos S. Economidis

Virginia Journal of Science

The European Environmental Agency formulated a biodiversity initiative in 1996 specifying a freshwater stream-monitoring program to inventory, identify and describe aquatic and terrestrial species in European Union countries. With one of the richest freshwater ichthyofaunas in Europe (126 fish taxa: 97 species and 29 subspecies of primary or secondary freshwater fishes), Greece has two extinct fish species, five listed as critically endangered, and 29 considered endangered and/or vulnerable. There are, however, no published identification guides that are available for identifying fish specimens from fresh waters in Greece. We present an English translation of the only available identification key (in Greek) …


Fisheries Research Contract Report No. 4 - Determining Waste Excretion Parameters From Barramundi Aquaculture: Final Report For Aquaculture Development Fund Of Wa, Brett Glencross, Neil Rutherford, Wayne Hawkins Sep 2003

Fisheries Research Contract Report No. 4 - Determining Waste Excretion Parameters From Barramundi Aquaculture: Final Report For Aquaculture Development Fund Of Wa, Brett Glencross, Neil Rutherford, Wayne Hawkins

Fisheries Research Contract Reports

This study was undertaken to evaluate the nutrient excretion budgets for each of three key commercial diets when fed to barramundi (Lates calcarifer). The diets differed primarily in their energy density ranging from 21.3 MJ/kg DM to 23.0 MJ/kg DM, with the protein content of each diet being relatively constant at around 550 g/kg DM. The determination of the nutrient excretion budgets required the assessment of the digestibilities of key nutrients from each of the diets and also the specific retention of nutrients over a prolonged period. This necessitated two digestibility trials and a growth trial.

An examination was also …


Fisheries Research Contract Report No. 3 - Early Life History Of Abalone (Haliotis Rubra, H. Laevigata): Settlement, Survival And Early Growth. Final Report For Frdc Project 1998/306, Dr Sabine Daume Sep 2003

Fisheries Research Contract Report No. 3 - Early Life History Of Abalone (Haliotis Rubra, H. Laevigata): Settlement, Survival And Early Growth. Final Report For Frdc Project 1998/306, Dr Sabine Daume

Fisheries Research Contract Reports

Australian abalone fisheries produce a high value, export-orientated products that provided 60% of the world supply in 1994 (Fleming, 2000). With wild abalone fisheries declining in countries worldwide, the interest in aquaculture products has increased substantially. The world production of abalone from aquaculture in 1999 was approximately 7,775 tonnes with only 89 tonnes (ca. 1%) being produced in Australia (Fleming, 2000). Abalone farming is expected to develop into a major industry and is a significant investment opportunity (McNamara, Victorian Aquaculture Strategy, May 1997). Future production from the numerous farms and sites either established, under construction or approved in Australia, could …


Fisheries Occasional Publication No. 8 - Department Of Fisheries Stakeholder Survey 2002, Tara Baharthah, Neil R. Sumner Jul 2003

Fisheries Occasional Publication No. 8 - Department Of Fisheries Stakeholder Survey 2002, Tara Baharthah, Neil R. Sumner

Fisheries Occasional Publications

A telephone survey of Department of Fisheries' stakeholders was conducted in November 2002 in order to evaluate their perception of the Department's management of commercial and recreational fishing, pearling and aquaculture, and fish and fish habitat protection. The survey also assessed satisfaction with the level of service provided to stakeholders and their involvement in the decision making process.

The sample comprised of 149 interviews - 40 representing the commercial fishing sector, 40 representing the recreational fishing sector, 40 representing fish and fish habitat protection, and 29 representing aquaculture and pearling.

In general, the stakeholders gave positive responses regarding the Department …


Fisheries Research Contract Report No. 2 - Towards An Assessment Of Natural And Human Use Impacts On The Marine Environment Of The Abrolhos Islands (Phase 1 : Data Consolidation And Scoping - Final Report For Frdc Project 2000/1 66), C. F. Chubb, K. Nardi Jul 2003

Fisheries Research Contract Report No. 2 - Towards An Assessment Of Natural And Human Use Impacts On The Marine Environment Of The Abrolhos Islands (Phase 1 : Data Consolidation And Scoping - Final Report For Frdc Project 2000/1 66), C. F. Chubb, K. Nardi

Fisheries Research Contract Reports

This project has drawn together existing research data relating to natural and human impacts on the Abrolhos Islands marine habitats. It has surveyed current uses of these habitats and placed anthropogenic impacts within the context of natural perturbations. Through public forum presentation and debate, this work has allowed real issues, not perceptions, to surface and be addressed properly. This was achieved by defining a strategic programme of research through a scientific workshop process involving all community stakeholders. A two volume Fisheries Research Report (WA) summarizes current knowledge and details the workshop proceedings and strategic research plan.


Fisheries Occasional Publications No. 4 - Research Project Assessment - A Decision Framework, W. J. Fletcher, J. W. Penn, H. G. Brayford Jun 2003

Fisheries Occasional Publications No. 4 - Research Project Assessment - A Decision Framework, W. J. Fletcher, J. W. Penn, H. G. Brayford

Fisheries Occasional Publications

Determining the relative priority for research proposals within an agency such as the Department of Fisheries, particularly when they are from different program areas, is a difficult task to achieve effectively. Traditionally within the Department, this task has been completed by a sub-group of the executive who have used their combined understanding of the broader issues and their experience of what has been done before and what is most likely to succeed. Such a system, while it has produced satisfactory outcomes, suffers from a lack of transparency and may be at longer-term risk when personnel changes occur and corporate knowledge …


Towards Sustainability Of Data-Limited Multi-Sector Fisheries: Australian Society For Fish Biology Workshop Proceedings September 2001 - Fisheries Occasional Publication No. 5, Stephen J. Newman, Daniel J. Gaughan, Gary Jackson, Michael C. Mackie, Brett W. Molony, Jill St John, Patricia Kailola Jun 2003

Towards Sustainability Of Data-Limited Multi-Sector Fisheries: Australian Society For Fish Biology Workshop Proceedings September 2001 - Fisheries Occasional Publication No. 5, Stephen J. Newman, Daniel J. Gaughan, Gary Jackson, Michael C. Mackie, Brett W. Molony, Jill St John, Patricia Kailola

Fisheries Occasional Publications

No abstract provided.


Male Reproductive Dynamics In The Caribbean Spiny Lobster Panulirus Argus, Jamie S. Heisig Apr 2003

Male Reproductive Dynamics In The Caribbean Spiny Lobster Panulirus Argus, Jamie S. Heisig

Biological Sciences Theses & Dissertations

The population size structure of the Caribbean Spiny Lobster, Panulirus argus, in the Florida Keys, Florida (USA) has undergone a dramatic shift as a result of fishing pressure on the large individuals of the population. Male lobsters are affected most by fishing because of sexual dimorphism in size and other studies have shown that male size has direct impacts on reproductive output (i.e., number of fertilized eggs/clutch) that are independent of female size. To assess more precisely the impact of male size on fertilization success, I conducted laboratory experiments and field observations to examine various male reproductive attributes over …


The Ecological Ramifications Of Disease And Density In The Caribbean Spiny Lobster, Panulirus Argus, Donald C. Behringer Jr. Apr 2003

The Ecological Ramifications Of Disease And Density In The Caribbean Spiny Lobster, Panulirus Argus, Donald C. Behringer Jr.

Biological Sciences Theses & Dissertations

In 1999, I discovered the first virus known to be pathogenic to any species of lobster. HLV-PA is a pathogenic herpes-like virus that infects juvenile Caribbean spiny lobster, Panulirus argus, in the waters off south Florida (USA), and it alters the behavior and ecology of this species in fundamental ways. Gross signs of HLV-PA infection are lethargy, morbidity, cessation of molting, and discolored, “milky” hemolymph that does not clot. HLV-PA infects the hemocytes of host lobsters, specifically the hyalinocytes and semi-granulocytes, but not the granulocytes. When hemolymph from infected donors was injected into healthy juvenile lobsters, 90% of the …


Identifying Nursery Areas Used By Inner Bay And Oceanic Pink Snapper ( Pagrus Auratus) To The Effect Of Prawn Trawling On Inner Bay Snapper Stocks - Final Report For Frdc Project 2001/061, D. J. Gaughan, Michael J. Moran, Melinda M. Ranaldi, John R. Watling Mar 2003

Identifying Nursery Areas Used By Inner Bay And Oceanic Pink Snapper ( Pagrus Auratus) To The Effect Of Prawn Trawling On Inner Bay Snapper Stocks - Final Report For Frdc Project 2001/061, D. J. Gaughan, Michael J. Moran, Melinda M. Ranaldi, John R. Watling

Fisheries Research Contract Reports

Final Report for FRDC Project 2001/061

Pink snapper (Pagrus auratus) is the main commercial and recreational finfish (Kailola et al., 1993) in the Shark Bay region. Pink snapper are distributed along much of the temperate and tropical coasts of Western Australia from east of Esperance on the south coast to north of Shark Bay on the west (Paulin 1990). Previous research using genetics (Johnson et al. 1986), tagging (Moran et al. 2004), and otolith microchemistry (Edmonds et al., 1989, 1999) have shown that pink snapper from the innermost parts of Shark Bay do not mix with the ocean fish

Juvenile …


Age And Growth Estimates Of The Winter Skate (Leucoraja Ocellata) In The Western Gulf Of Maine, James A. Sulikowski, Michael D. Morin, Seung H. Suk, William Huntting Howell Jan 2003

Age And Growth Estimates Of The Winter Skate (Leucoraja Ocellata) In The Western Gulf Of Maine, James A. Sulikowski, Michael D. Morin, Seung H. Suk, William Huntting Howell

Biological Sciences

The northwest Atlantic population of thorny skates (Amblyraja radiata) inhabits an area that ranges from Greenland and Hudson Bay, Canada, to South Carolina. Despite such a wide range, very little is known about most aspects of the biology of this species. Recent stock assessment studies in the northeast United States indicate that the biomass of the thorny skate is below the threshold levels mandated by the Sustainable Fisheries Act. In order to gain insight into the life history of this skate, we estimated age and growth for thorny skates, using vertebral band counts from 224 individuals ranging in size from …


An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne H. Alonzo, Paul Switzer, Marc Mangel Jan 2003

An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne H. Alonzo, Paul Switzer, Marc Mangel

Faculty Research & Creative Activity

Summary 1. Changes in species' abundance and distributions caused by human disturbances can have indirect effects on other species in a community. Although ecosystem approaches to management are becoming increasingly prevalent, they require a fuller understand- ing of how individual behaviour determines interactions within and between species. 2. Ecological interactions involving krill are of major importance to many species within the Antarctic. Despite extensive knowledge of the ecosystem that they occupy, there is still incomplete understanding of the links between species and the effect of environmental conditions on these interactions. In this study, we extended a behavioural model used previously …


An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne Alonzo, Paul Switzer, Marc Mangel Jan 2003

An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne Alonzo, Paul Switzer, Marc Mangel

Faculty Research & Creative Activity

Summary 1. Changes in species' abundance and distributions caused by human disturbances can have indirect effects on other species in a community. Although ecosystem approaches to management are becoming increasingly prevalent, they require a fuller understand- ing of how individual behaviour determines interactions within and between species. 2. Ecological interactions involving krill are of major importance to many species within the Antarctic. Despite extensive knowledge of the ecosystem that they occupy, there is still incomplete understanding of the links between species and the effect of environmental conditions on these interactions. In this study, we extended a behavioural model used previously …


Demographic Assessment Of The Blue Crab (Callinectes Sapidus) In Chesapeake Bay Using Extractable Lipofuscins As Age Markers, Se-Jong Ju, David H. Secor, H. Rodger Harvey Jan 2003

Demographic Assessment Of The Blue Crab (Callinectes Sapidus) In Chesapeake Bay Using Extractable Lipofuscins As Age Markers, Se-Jong Ju, David H. Secor, H. Rodger Harvey

OES Faculty Publications

The blue crab (Callinectes sapidus) plays an important economic and ecological role in estuaries and coastal habitats from the Gulf of Mexico to the east coast of North America, but demographic assessments are limited by length-based methods. We applied an alternative aging method using biochemical measures of metabolic byproducts (lipofuscins) sequestered in the neural tissue of eyestalks to examine population age structure. From Chesapeake Bay, subsamples of animals collected from the 1998-99 (n-769) and 1999-2000 (n=367) winter dredge surveys were collected and lipofuscin was measured. Modal analysis of the lipofuscin index provided separation into three modes, whereas carapace-width …


Hydrodynamic Stability Of Swimming In Ostraciid Fishes: Role Of The Carapace In The Smooth Trunkfish Lactophrys Triqueter (Teleostei : Ostraciidae), Ian K. Bartol, Morteza Gharib, Daniel Weihs, Paul W. Webb, Jay R. Hove, Malcolm S. Gordon Jan 2003

Hydrodynamic Stability Of Swimming In Ostraciid Fishes: Role Of The Carapace In The Smooth Trunkfish Lactophrys Triqueter (Teleostei : Ostraciidae), Ian K. Bartol, Morteza Gharib, Daniel Weihs, Paul W. Webb, Jay R. Hove, Malcolm S. Gordon

Biological Sciences Faculty Publications

The hydrodynamic bases for the stability of locomotory motions in fishes are poorly understood, even for those fishes, such as the rigid-bodied smooth trunkfish Lactophrys triqueter, that exhibit unusually small amplitude recoil movements during rectilinear swimming. We have studied the role played by the bony carapace of the smooth trunkfish in generating trimming forces that self-correct for instabilities. The flow patterns, forces and moments on and around anatomically exact, smooth trunkfish models positioned at both pitching and yawing angles of attack were investigated using three methods: digital particle image velocimetry (DPIV), pressure distribution measurements, and force balance measurements. Models …


Fisheries Research Report No. 142 - Identifying The Development Stages Of Preserved Eggs Of Snapper, Pagrus Auratus, From Shark Bay, Western Australia, J. Norriss, Gary Jackson Dec 2002

Fisheries Research Report No. 142 - Identifying The Development Stages Of Preserved Eggs Of Snapper, Pagrus Auratus, From Shark Bay, Western Australia, J. Norriss, Gary Jackson

Fisheries Research Reports

The characteristics used to identify 19 developmental stages of preserved eggs of snapper, Pagrus auratus, collected from Shark Bay, Western Australia, during annual plankton surveys, are described and illustrated. A key is provided to enable the age of each egg stage to be estimated based on sea surface temperature and salinity observed during sampling. This report is intended as a reference for inexperienced staff, to ensure that between-year comparisons of snapper spawning biomass, estimated using the daily egg production method, are based on consistent egg staging and ageing methods.


Fisheries Research Report No. 143 - Methods Used In The Collection, Preparation And Interpretation Of Narrow-Barred Spanish Mackerel (Scomberomorus Commerson) Otoliths For A Study Of Age And Growth In Western Australia, Paul Lewis, M. C. Mackie Dec 2002

Fisheries Research Report No. 143 - Methods Used In The Collection, Preparation And Interpretation Of Narrow-Barred Spanish Mackerel (Scomberomorus Commerson) Otoliths For A Study Of Age And Growth In Western Australia, Paul Lewis, M. C. Mackie

Fisheries Research Reports

The narrow-barred Spanish mackerel (Scomberomorus commerson) is wide ranging throughout the Indo-West Pacific region where it has been the subject of various age and growth studies. Methods used in these studies have varied considerably and in some cases may have led to misleading conclusions. The purpose of this report, therefore, is to document in detail the methods used in determining the age and growth during a FRDC funded stock assessment of the species in the waters off Western Australia. These methods are considered to optimise the collection, processing, accuracy of microincrement counts, and interpretation of the annuli in both whole …


Workshop On Sustainable Development Of Marine Fish Farming In Wa, Peter Rogers, R Fletcher Oct 2002

Workshop On Sustainable Development Of Marine Fish Farming In Wa, Peter Rogers, R Fletcher

Fisheries Management Papers

The purpose of this paper is twofold. First to provide an overview of the role of government and more particularly the Department of Fisheries and second to outline government expectations for aquaculture development agencies in the implementation of sustainable development initiatives and the effect this could have on the management of aquaculture within WA.


Review Of Recreational Take Of Coral In Western Australia. A Discussion Paper., Department Of Fisheries Oct 2002

Review Of Recreational Take Of Coral In Western Australia. A Discussion Paper., Department Of Fisheries

Fisheries Management Papers

This discussion paper has been prepared by the Department of Fisheries (Western Australia) to address the issue of recreational collection of coral in coastal waters of Western Australia. The paper describes: • popular coral locations in WA; • management issues associated with the recreational collection of corals; • management objectives and strategies as possible options to address the issue of recreational collection of corals; and • seeks public input on the proposed management objectives and strategies.


Fisheries Research Report No. 141 - A Guide To Good Otolith Cutting, Jerry Jenke Sep 2002

Fisheries Research Report No. 141 - A Guide To Good Otolith Cutting, Jerry Jenke

Fisheries Research Reports

This is a guide for embedding and sectioning fish otoliths. It is based on many years of otolith sectioning experience and is written as a recipe book for novice and expert alike. Included is a method for the enhancement of the clarity of small otoliths for improved sectioning, development of custom made tools, as well as a list of do’s and don’ts and hints to make the job easier. Use of this guide will assist in the most reliable interpretation of an otolith's internal structure, thereby improving ageing studies in general.