Ecology and Evolutionary Biology Commons^™

Contribution Of Zooplankton Lipids To The Flux Of Organic Matter In The Northern Adriatic Sea, Mirjana Najdek, Staša Puškarić, Alexander B. Bochdansky

OES Faculty Publications

Analyses of particulate material collected by sediment traps moored at a location in the northern Adriatic Sea in 1991 revealed the presence of zooplankton fatty acids, even though zooplankton and other 'swimmers' killed by the trap's preservative were carefully removed. Laboratory experiments were conducted to (1) prove the existence of zooplankton lipids within fecal pellets, (2) exclude the possibility of incomplete separation of swimmers and other material as eventual contamination with polyunsaturated fatty acids in fecal pellets, (3) evaluate the importance of zooplankton lipids to mass flux and (4) reveal the mechanisms which lead to excretion of undigested organic matter, …

Proceedings Of The Charter Boat Management Workshop Held As Part Of The First National Fisheries Manager Conference Terrigal Nsw 21 September 1993, A. E. Magee

Fisheries Management Papers

General concern of all states was the actual AND potential impact of charter fishing on the resource and the inability to measure such impacts. The perceived problem with dual licensing was unregulated effort and the abilit to circumvent management controls. This paper provides current charter boat management arrangements in Australia, why they should be managed, types of charter vessels, Licensing, Management of recreational only charter vessels, Non-consumptive charters, Management guides and small scale charter operators, Commonwealth jurisdiction, Development of agreed strategies and Identification of future needs.

Age And Growth Of Larval And Juvenile Atlantic Croaker, Micropogonias Undulatus, From The Middle Atlantic Bight And Estuarine Waters Of Virginia, Stephen W. Nixon

Biological Sciences Theses & Dissertations

Sagittal otoliths were used to determine the age and growth of 605 larval and juvenile Atlantic croaker, Micropogonias undulatus, collected in the Middle Atlantic Bight (MAB) and estuarine waters of Virginia. A Laird-Gompertz model (r2 = 0.95) was used to describe the growth of croaker up to 65 mm standard length (SL) and 142 days (t): S1_(t) = 2.657 Exp {4.656 [1-Exp (-0.008lt)]}; SL_(t) = standard length at day t. Generally, croaker collected inshore were larger and older than those collected offshore, indicating estuarine immigration from offshore spawning grounds. Back-calculated hatch-dates indicated spawning over an 8- month period …

The Influence Of Temperature Salinity And Postlarval Transport On The Distribution Of Juvenile Spiny Lobsters, Panulirus Argus, In Florida Bay, Jennifer Marie Field

Biological Sciences Theses & Dissertations

Florida Bay is a major nursery for the Caribbean spiny lobster, Panulirus argus. The Bay contains a series of hardbottom or seagrass-covered basins separated by mudbanks, which serve as barriers to water circulation and presumably to transport of postlarvae. Temperatures can fluctuate dramatically in the basins and salinities range from 35 ppt to > 50 ppt. In this study I: i) investigated the physiological tolerance of spiny lobster postlarvae to combinations of temperature and salinity representative of conditions in Florida Bay, and ii) examined how postlarval availability and habitat structure influence spiny lobster recruitment into basins. I measured juvenile lobster …

Phytoplankton Assemblages Associated With A Bloom Of Ptychodiscus Brevis Off The North Carolina Coast, Traycie Lea West

Biological Sciences Theses & Dissertations

A bloom of the dinoflagellate Ptychodiscus brevis occurred off the North Carolina coast in late 1987, and samples were forwarded by NOAA to the Old Dominion University Phytoplankton Laboratory for total phytoplankton analysis. Six sampling stations were chosen to represent different bloom scenarios and these six were clustered into three site groups based on the concentrations of statistically significant taxa. Abundances of phytoplankton taxonomic groups over time were examined in relation to P. brevis concentrations to identify any general tendencies. These results indicated the total phytoplankton concentration, and most taxonomic groups, increased at all three site groups regardless of the …

Fisheries Research Report No.100 - The Impact Of Trawling For Saucer Scallops And Western King Prawns On The Benthic Communities In Coastal Waters Off South-Western Australia, L. J.B. Laurenson, P. Unsworth, J. W. Penn, R. C.J. Lenanton

Fisheries Research Reports

A two year study was undertaken to collect data for the assessment of the impact of the saucer scallop and western king prawn trawl fisheries on the benthic communities in coastal waters off south western Australia, between 31°20'5 and 34°23'5 latitude.

Monitoring of reported commercial landings, on-board sampling of commercial catches, research vessel trawl surveys, experimental and exploratory trawling, and underwater television observations, have enabled the development of an extensive data-base on the fishery and benthic communities of the region.

These data indicate that the existing fishery operates on a number of relatively small, discrete grounds where saucer scallops or …

Fisheries Management Paper No 53 - Rock Lobster Industry Advisory Committee - Report To The Minister For Fisheries And Management Arrangements For 1992/93, Fisheries Department Of Western Australia

Fisheries Management Papers

The Minister for Fisheries announced the 1992/93 fishing season management arrangements for West Coast Rock Lobster Fishery on 11 August 1992. These arrangements arose as a result of the Minister's consideration of the Rock Lobster Industry Advisory Committee's recommendations outlined in Fisheries Management Paper no.46.

Following this announcement, on 28 August 1992, the Western Australian Fishing Industry Council Sub-Committee on rock lobster submitted a range of alternative management proposals.

The Rock Lobster Industry Advisory Committee (RLIAC) met in Perth on the 9 September 1992 at the request of the Minister for Fisheries to further examine and report on management arrangements.

Evaluation Of Long Term Changes In The Macrobenthic Community Of The Southern Branch Of The Elizabeth River, Virginia, William S. Hunley

Biological Sciences Theses & Dissertations

Long-term changes in the macrobenthos of the Southern Branch of the Elizabeth River, Virginia were investigated by comparing the present study of community structure with that described ten years earlier by Hawthorne (1980). The results indicated that dominant organisms remained relatively constant in composition but exhibited considerable fluctuation in density. Differences in diversity and spatial distribution of fauna were also observed relative to the previous decade.

Multivariate statistical analyses indicated the macrobenthos exhibited significant spatial and seasonal patterns. Sediments characterized as silts and clays predominated down river while sandier sediment types were most common farther upriver. The spatial distributions of …

Observations On The Pearl Oyster Fishery Of Kuwait, S. M. Almatar, Kent E. Carpenter, R. Jackson, S. H. Alhazeem, A. H. Alsaffar, A. R. A. Ghaffar, C. Carpenter

Biological Sciences Faculty Publications

The pearl oyster fishery of Kuwait was monitored daily from January 1989 to May 1990. Landings of pearl oysters in 1989 totaled 287 tons with a market value of U.S. $1.0 million. Commercial pearls (>3 mm) were estimated to be present in one of every 4200 oysters. Most of the pearl oysters landed were new recruits with hinge lengths between 40-56 mm. There was a curvilinear relationship between total weight and size of oysters (length) and the sex ratio approached 1:1. Spawning occurs throughout the year, with a spat settlement peak in early fall. Over the size range examined …

Changes In The Sea-Ice Brine Community During The Spring-Summer Transition, Mcmurdo Sound, Antarctica .2. Phagotrophic Protists, Diane K. Stoecker, Kurt R. Buck, Mary Putt

OES Faculty Publications

The land-fast sea-ice brine contains a diverse phagotrophic protist assemblage consisting of < 5 mum heterotrophic flagellates, Cryothecomonas spp., heterotrophic dinoflagellates, and heterotrophic and mixotrophic ciliates. Fine-scale horizontal spatial variability is a feature of this assemblage; samples taken within 1 m of each other can be dominated by different heterotrophic protists. Many of the larger heterotrophic protists found in the brine are also found in the water column. The photosynthetic ciliate Mesodinium rubrum is also common. In mid to late austral spring, the heterotrophic assemblage accounts for ca 10% of the total protist biomass in the brine and is dominated by Cryothecomonas spp. This flagellate …

Benthic Microalgal Production At Stellwagen Bank, Massachusetts Bay, Usa, Lawrence B. Cahoon, Guy R. Beretich Jr., Carrie J. Thomas, Amy M. Mcdonald

OES Faculty Publications

Benthic microalgal chlorophyll a and production were measured at 3 sites at Stellwagen Bank, a cold temperate continental shelf habitat in Massachusetts Bay, USA, during August 1991. Benthic microalgal chlorophyll a averaged 39.8 Mg M^-2, vs average integrated phytoplankton chlorophyll a of 25.9 mg m^-2. Gross benthic microalgal production, measured by oxygen exchange in clear and opaque benthic chambers, averaged 20.9 mg C m^-2 h^-1. This production was supported by average daily light fluxes to the bottom that never exceeded 1 % of surface incident radiation and were as low as 4.7 μE …

A Multivariate Characterization Of Assemblages Of Planktonic Mysids Decapods And Sergestids In The Chesapeake Bay Mouth Area, John Charles Seibel

Biological Sciences Theses & Dissertations

This study is the first to focus on the assemblages of the planktonic mysids, decapods, and sergestids found in the lower Chesapeake Bay. The assemblages of these organisms in the lower Chesapeake Bay and nearby shelf were characterized using three different statistical approaches, and the methods used were evaluated for their effectiveness at delineating ecologically meaningful assemblages. Three stations were sampled across the Chesapeake mouth and one offshore, with oblique and neuston net tows. Twenty-seven larval stages, representing at least 23 species, were found in sufficient numbers to be analyzed statistically. The statistical approaches were each based upon a different …

Seasonal Phytoplankton Development Within Three Rivers In The Lower Chesapeake Bay Region, Harold G. Marshall, Lewis F. Affronti

Biological Sciences Faculty Publications

The seasonal and inter-annual concentrations of phytoplankton were studied over a 50 month period in the lower James, York and Rappahannock Rivers (USA). Differences in the onset, duration and magnitude of major seasonal growth periods varied from year to year. There was a tendency for spring, summer and fall maxima, with a winter period of reduced abundance. An additional study of picoplankton over a 12 month period indicated greatest abundance during summer and fall, with least development in winter.

Population Ecology Of Polydora Ligni (Polychaeta: Spionidae). I. Seasonal Variation In Population Characteristics And Reproductive Activity, Roman Zajac

Biology and Environmental Science Faculty Publications

A population of the polychaete Polydora ligni Webster was studied during 1982 and 1983 in Alewife Cove, Connecticut, USA, to determine seasonal changes in population characteristics. During early spring (March and April), the population was comprised of primarily large adults that had over-wintered. Females in this group exhibited the highest mean individual fecundity over the year (> 2000 larvae per brood). However, total larval production at this time was low (5200 to 208 000 larvae m^-2 per 14 d) due to low densities of adults. Population density increased slowly during spring as juveniles produced by overwintering adults recruited into …

Population Ecology Of Polydora Ligni (Polychaeta: Spionidae). Ii. Seasonal Demographic Variation And Its Potential Impact On Life History Evolution, Roman Zajac

Biology and Environmental Science Faculty Publications

Seasonal demographic variation was studied in an estuarine population of the opportunistic polychaete Polydora ligni between May 1982 and November 1983 in Alewife Cove, Connecticut, USA. The demography of 15 cohorts settling during this period was analyzed using life cycle graph models. Cohorts settling in spring and early summer had the shortest life spans (≈ 10 wk); highest survivorship over all life cycle stages and adult females produced an estimated maximum of 6 larval broods. Early adult stages contributed most to population growth during this period, and the potential for population growth, λ, was the highest during the study. Late …

A Laboratory Study Of Predation On The Trinidadian Guppy, Poecilia Reticulata, By Two Natural Piscine Predators: Effects Of Predator Size, Prey Size, And Habitat Complexity, Hayden Thomas Mattingly

Biological Sciences Theses & Dissertations

Test populations of different-sized guppies, Poecilia reticulata, were exposed to individuals of two natural predatory species, the pike cichlid Crenicichla a/ta and the killifish Rivulus harti, under conditions of varying prey (guppy) density and habitat complexity in the laboratory. Rivulus fed most frequently on newborn and juvenile guppies < 14 mm. Crenicichla consumed more and larger guppies than did Rivulus. The mean guppy size eaten by Crenicichla was dependent on the length of the individual predator, but as a group, the 15 Crenicichla tested were non-selective with respect to guppy size and gender. The prey gender preference of Rivulus could not he determined …

Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane

Biological Sciences Theses & Dissertations

A study of the subtidal macrobenthos in Back Bay, Virginia was conducted to examine community structure in relation to sedimentary and water quality characteristics. Samples were collected in August and November of 1987 and February and May of 1988 at ten stations.

Three site groups and three temporal groups were identified by cluster analyses of species abundance. Species composition between site groups was relatively homogeneous and eight species accounted for most of the variation between site groups. A comparison of plots of the biological and physical data in discriminant space suggested that variations in the biological data between site groups …

The Future For Recreational Fishing Final Report Of The Recreational Fishing Advisory Committee, Recreational Fishing Advisory Committee

Fisheries Management Papers

This report discusses: What Recreational fishing means to Western Australia's estimated 300,000 fishers. Conservation and equality in catch sharing was at the heart of the Committee's investigations into developing strategies for the future management of important recreational fish stocks.

Observations Of The Phytoplankton Standing Crop At The Shelf Margin Of The Mid Atlantic Bight, Bruce B. Wagoner, Harold G. Marshall

Biological Sciences Faculty Publications

A comparison of the total percentage cell abundance and cell biovolume relationships of major phytoplankton categories was made between two station sets across the shelf margin. Diatom values for abundance and biovolume were greater at oceanic stations compared to the outer shelf stations, with dinoflagellates having the reverse pattern. The composite contributions to biovolume and abundance in the standing crop from other phytoplankton categories were greater over the outer shelf than beyond the shelf margin. The major source of biovolume (biomass) from the outer shelf and these oceanic stations came from the diatoms and dinoflagellates, with an average mean of …

Development And Evaluation Of Tracer Particles For Use In Microzooplankton Herbivory Studies, Mary Putt

OES Faculty Publications

Two methods of preparing algae for use as tracer particles in single species measurements of microzooplankton herbivory were evaluated. Algae were either heat-killed and labelled with 5-(4,6-dichlorotriazin-2-yl amino fluorescein) (DTAF) (Rublee & Gallegos 1989; Mar, Ecol. Prog. Ser. 51: 221-227) or stained with hydroethidine (HYD). Both DTAF and HYD-stained algae were readily visible within the digestive vacuoles of most microzooplankton collected in estuarine and coastal waters of Massachusetts (USA) and preserved with Lugol's iodine. However, DTAF was ineffective at staining several chromophytic algae and the heat-kill process reduced cell volume by ≥ 50% in several of the algae which were …

Fisheries Research Report No. 89 - Relationships Among Partial And Whole Lengths And Weights For Western Australian Pink Snapper Chrysophrys Auratus (Sparidae), M. J. Moran, C. Burton

Fisheries Research Reports

Pink snapper, Chrysophrysauratus (Sparidae) is one of the major commercial and recreational fish in Western Australian inshore waters. This report presents a number of equations and conversion factors for management and scientific study of the species. Equations to calculate total lengths from partial lengths will facilitate enforcement of minimum legal lengths when snapper are landed in a "head-off" condition. For fisheries science purposes, there are equations to convert among total length, standard length and length to caudal fork; and to convert lengths and weights of processed fish to whole lengths and weights. Length-weight relationships are presented and compared with those …

Fisheries Research Report No. 84 - The Marine Open Shelf Environment: Review Of Human Influences, D. A. Hancock

Fisheries Research Reports

For the purpose of this review, the marine environment has been classified into three physical zones - the littoral zone, the open-shelf environment and the coral reef. Since the boundaries are arbitrary, there will inevitably be some overlap, but for this review the subject matter will be related to the area between low water of ordinary spring tides and the edge of the continental shelf; i.e., to a depth varying to 200 metres.

Human influences may have a dual role in affecting the marine environment, firstly in a causative manner and secondly in providing a remedy, in which case the …

Freshwater Fishes Of Shipstern Nature Reserve, Caspar F. A. Bijleveld

Physiology Faculty Research Publications

A survey of fishes in and around Shipstern Nature Reserve in Northern Belize, Central America, was carried out over a period of eight months, from February to September 1990. Its purpose was to establish a preliminary list of the fishes of Shipstern Nature Reserve, including descriptions, distribution and collecting data and additionally to describe some of the habitats in which the fishes were found. This study focuses on fishes considered to be freshwater species. These occurred for the greater part in brackish habitats. Nevertheless, a few fish considered as marine species were caught in the waters of the reserve and …

Natural And Disturbance-Induced Demographic Variation In An Infaunal Polychaete, Nephtys Incisa, Roman Zajac, Robert B. Whitlatch

Biology and Environmental Science Faculty Publications

Demography of the infaunal polychaete Nephtys incisa was investigated for periods of 1 yr prior to and following disturbance (dredge material disposal) at a site in central Long Island Sound, USA. Infaunal grab samples were taken at 5 stations 200 m to 3 km apart. The demography of populations at each station was based on age-classes spanning juveniles to adults 4 + yr of age. Age-specific survivorship and fecundity were based on changes in mean density of each cohort and a positive correlation between female size and egg production, respectively. Analyses of population matrix models indicated pre-disposal populations had positive …

Effects Of Inter-Specific Density And Food Supply On Survivorship And Growth Of Newly Settled Benthos, Roman Zajac, Robert B. Whitlatch, Richard W. Osman

Biology and Environmental Science Faculty Publications

Using a laboratory model system comprised of newly settled oysters Crassostrea virginica and established fouling species (Botrylloides sp. initially, and others including Styela clava and Ciona intestinalis as the experiment progressed), we tested how differences in food supply and competitor density may affect post-settlement surivorship and growth of sessile marine invertebrates over a 44 d period. After 15 d, results were mixed but indicated that both food and density conditions affected growth and survivorship significantly, with some suggestion of high food levels ameliorating high density effects However, 44 d after settlement, oysters had reduced survivorship and growth when competitors …

Distribution And Marketing Of Western Australia Rock Lobster., P. J. Monaghan

Fisheries Management Papers

This report describes the marketing and distribution of Western Australian rock lobster products in the major consuming countries namely, USA, Japan and Taiwan. It is based on a study which was commissioned by the Fisheries Department of Western Australia who sought, for the benefit of industry generally, an understanding of the world lobster markets.

Picoplankton/Phytoplankton Dynamics In Hampton Roads, Virginia, Leslie E. Dorworth

OES Theses and Dissertations

The biomass distribution of the three main size components of the phytoplankton (net, nano, and picoplankton) was examined in the lower Chesapeake Bay. Work was done at two stations during the spring and neap tidal cycles when freshwater flow into the bay was at its seasonal minimum and maximum. Emphasis was placed on how the picoplankton ( < 2.0 μm, > 0.2 μm) reacted during the sampling period.

Picoplankton made up approximately 13% of the total biomass, during the observed time period, at the more oceanic station. The picoplankton fraction contributed up to 16% of the total biomass at the estuarine station. From this …

Effects Of Resident Species On Recruitment Into A Community: Larval Settlement Versus Post-Settlement Mortality In The Oyster Crassostrea Virginica, Roman Zajac, Richard W. Osman, Robert B. Whitlatch

Biology and Environmental Science Faculty Publications

Laboratory and field experiments revealed that a variety of species of common, sessile invertebrates, including barnacles, ascidians, and bryozoans, affected the settlement and post-settlement abundance of the oyster Crassostrea virginica (Gmelin). While the nature of the effects varied, most species both reduced oyster settlement by covering and removing substrate available for attachment, and increased settlement on adjacent surfaces. The solitary ascidians Ciona intestinalis (L.) and Styela clava (Herdman), were found to be predators of oyster larvae. Post-settlement survivorship and growth were also strongly affected by the presence of sessile species. In most cases the effects were negative and correlated with …

Southern Demersal Gillnet And Longline Fishery., Management Advisory Committee

Fisheries Management Papers

In its report to the Ministier for Fisheries in November 1986, the Southern Western Australian Shark Working Group recommended the establishment of an Industry/Government Mangement Advisory Committee to provide managememt advice on the fishery to the Minister for Fisheries. The Advisory Committee held its first meeting in Albany on 23 February 1989. After being briefed on the state of shark stocks, the Committee's deliberations fell into three broad categories. In the first category there was sufficient time and information available to make a recommendation to the Minister for Fisheries. In the second category, discussion commenced, but was held over to …

Management Of The Perth Metropolitan Purse-Seine Fishery., N. Moore

Fisheries Management Papers

This report outlines the management plan for the limited entry purse-seine fishery for small pelagic fish in coastal waters between Lancelin and Cape Bouvard and seaward to the 200 mile limit of the Australian Fishing Zone. The plan includes Cockburn Sound.