Showing papers by "National Marine Fisheries Service published in 1991"
TL;DR: It is reported that an oceanic diatom was able to grow at a near maximum specific rate of about 1.0 per day at a cellular Fe:C ratio of 2 μmol: mol, about 25% of the amount needed for the same rate in a related estuarine species, and 2–20% of values previously used to estimate algal Fe requirements in sea water.
Abstract: DESPITE the controversy on the importance of iron in limiting phytoplankton growth and affecting air–sea exchange of CO2 in the ocean1–4, there is very little information on cellular iron requirements for growth. The few data available5,6 come from species isolated from coastal sea water where dissolved Fe levels are 10–1,000 times higher than those (≤0.1 nM) in the open ocean1,7. Species from oceanic waters require much lower external Fe concentrations for growth than do comparable coastal species8. Here we report that an oceanic diatom was able to grow at a near maximum specific rate of about 1.0 per day at a cellular Fe:C ratio of 2 μmol: mol, about 25% of the amount needed for the same rate in a related estuarine species, and 2–20% of values previously used to estimate algal Fe requirements in sea water1,2. These results have important implications concerning iron limitation of primary productivity in the ocean and cell biology of iron in oceanic algae.
281 citations
TL;DR: Exposure studies showed that xenobiotic metabolism, as reflected in hepatic activities of XMEs and levels of FACs in the bile, is altered by exposure to environmental contaminants.
Abstract: English sole (Parophrys vetulus) are susceptible to the development of hepatic disease, including neoplasia, as a result of environmental exposure to polycyclic aromatic hydrocarbons (PAHs). The metabolism of PAHs, believed to be an essential factor in the development of neoplasia, has received considerable study in English sole, except that xenobiotic metabolizing enzymes (XMEs) have not been wellstudied in this species. In the present work, the activities of hepatic aryl hydrocarbon hydroxylase (AHH), glutathione-S-transferase (GST), and epoxide hydrolase (EH) were measured in English sole exposed to several organic xenobiotics. These studies included an examination of the effects of captivity, the short-term responses of hepatic XME activities to several xenobiotic compounds, and detailed studies of the time- and dose-responses of hepatic XME activities to both a representative carcinogenic PAH (benzo[a]pyrene) and to a complex mixture of contaminants extracted from a sediment collected from a polluted area of Puget Sound, WA. Additionally, during the captivity and time- and dose-response studies, the levels of fluorescent aromatic compounds (FACs) were measured in the bile of the fish, both to provide an estimation of contaminant exposure and to evaluate the time- and dose-responses of this measure. The results of the captivity studies showed that the levels of FACs in bile were most affected by captivity, primarily as a result of changes in feeding status. The results of the exposure studies showed that xenobiotic metabolism, as reflected in hepatic activities of XMEs and levels of FACs in the bile, is altered by exposure to environmental contaminants. Whereas hepatic AHH activity could be rapidly and substantially increased by such exposure, activities of GST and EH were not affected, even up to 42 days after exposure. Moreover, because fish were exposed to a wide range of doses of chemicals or mixtures of chemicals which are known to be present in contaminated estuaries, and the responses of the hepatic AHH system and the levels of FACs in bile were measured at several time periods after exposure, the results provided substantial validation for the use of these two measures as bioindicators of exposure to environmental contamination in benthic fish.
280 citations
196 citations
TL;DR: A method is presented for estimating age-specific mortality based on minimal information: a model life table and an estimate of longevity and this approach uses expected patterns of mammalian survivorship to define a general model of agespecific mortality rates.
Abstract: A method is presented for estimating age-specific mortality based on minimal information: a model life table and an estimate of longevity. This approach uses expected patterns of mammalian survivorship to define a general model of agespecific mortality rates. One such model life table is based on data for northern fur seals (Callorhinus ursinu.r) using Siler’s ( 1979) 5-parameter competing risk model. Alternative model life tables are based on historical data for human females and on a published model for Old World monkeys. Survival rates for a marine mammal species are then calculated by scaling these models by the longevity of that species. By using a realistic model (instead of assuming constant mortality), one can see more easily the real biological limits to population growth. The mortality estimation procedure is illustrated with examples of spotted dolphins (Stenella attenuata) and harbor porpoise (Phocoena phocoena).
189 citations
TL;DR: This paper traces the development of applications of biochemical genetic methods to problems of fishery management over a period of four decades, with a plea to recognize the unique attributes of properly applied protein electrophoresis in fisherymanagement.
Abstract: This paper traces the development of applications of biochemical genetic methods to problems of fishery management over a period of four decades. In the 1950s, details of presumed genetic structuring offish species appeared destined for revelation through Mendelian characters identified by immunogenetic procedures. In the 1960s, immunogenetic methods were displaced by protein electrophoresis, with a proliferation of reports of genotypic and allelic data for protein-coding loci. In the 1970s, disagreement about the biological significance of protein polymorphisms delayed acceptance of management applications of this variation. In the 1980s, management applications included identification of relationships among populations, analyses of mixed stock fisheries, and uses in fish culture, conservation biology and forensics. The complementary relationship between protein electrophoresis and nucleic acid technologies is stressed, with a plea to recognize the unique attributes of properly applied protein electrophoresis in fishery management.
185 citations
TL;DR: The hypothesis that lesions in wild English sole can be caused by exposure to certain hepatoxic and hepatocarcinogenic xenobiotic compounds in the marine environment is based on the demonstration of significant and consistent statistical associations between levels of aromatic hydrocarbons in sediment and prevalences of these idiopathic liver lesions.
Abstract: English sole (Parophrys vetulus) inhabiting polluted waterways and embayments of Puget Sound, Washington, are affected with a variety of multiple, co-occurring idiopathic hepatic lesions, including unique degenerative conditions, putatively preneoplastic foci of cellular alteration, and neoplasms. Results of a statistical analysis of the patterns of co-occurrence of these lesions in wild English sole are consistent with the concept that these lesions represent morphologically identifiable steps forming a sequence of progression ultimately leading to the development of hepatic neoplasms. This progressive sequence parallels the pattern identified in experimental models of chemically induced hepatocarcinogenesis in rodents. The rationale for the hypothesis that these lesions in wild English sole can be caused by exposure to certain hepatoxic and hepatocarcinogenic xenobiotic compounds in the marine environment is based on the demonstration of significant and consistent statistical associations between levels of aromatic hydrocarbons (AHs) in sediment and prevalences of these idiopathic liver lesions; a significant contribution by sediment AHs to the variability in hepatic neoplasm prevalence in a logistic regression model; significantly increased probabilities for several idiopathic lesions in sole from chemically contaminated sites in Puget Sound; significant correlations between uptake of polycyclic aromatic hydrocarbons, as measured by levels of fluorescent metabolites of aromatic compounds in bile of sole, and prevalences of several hepatic lesion types; and experimental induction of unique degenerative, proliferative, and putatively preneoplastic focal lesions in English sole injected with either benzo(a)pyrene or a polycyclic aromatic hydrocarbons (PAH) enriched fraction of an extract from a contaminated urban sediment from Puget Sound.(ABSTRACT TRUNCATED AT 250 WORDS)
181 citations
TL;DR: In this article, an empirical study of a Pacific coast trawl fishery indicates that the firm's flexibility of product decision is tightly constrained by its technology and cost structure, and that as the resource stock for the regulated species, sablefish, deteriorates and the trip quota progressively tightens, the firm cannot sufficiently reorganize its product bundle to preclude increasingly large sable fish disposal.
126 citations
01 Jan 1991
125 citations
TL;DR: It is recommended that the indigenous populations of Spain be fully identified and protected, and that the existing hatchery stocks be replaced with local natural populations.
117 citations
TL;DR: In this article, the migration and settlement pattern of 0-group summer flounder and southern flounders in an estuarine nursery are described, showing that the two species were found concentrated in different habitats.
116 citations
TL;DR: Findings indicate that schooling fish gain information by interpreting conspecific behavior, and are consistent with research showing that animals balance the conflicting demands of foraging and vigilance.
Abstract: Recent studies show that fish forage actively when perceived risk is low, but decrease foraging and increase vigilance when perceived risk is high. Isolated juvenile chum salmon,Oncorhynchus keta, were visually exposed to groups of conspecifics engaged in different activities to examine their ability to gain information about foraging opportunity and risk by interpreting conspecific behavior. Isolates ate most when exposed to feeding groups, less when exposed to nonfeedig groups, and least when exposed to alarmed groups. Isolates exposed to alarmed conspecifics also spent more time motionless than did fish exposed to either feeding or nonfeeding conspecifics. These findings indicate that schooling fish gain information by interpreting conspecific behavior, and are consistent with research showing that animals balance the conflicting demands of foraging and vigilance.
TL;DR: The weighted average heart rate (WAHR), calculated from measured heart rate and the percentage time spent on the water surface or submerged, increased linearly with swimming speed for both species, similar to the response observed for terrestrial mammals.
Abstract: Respiratory, metabolic, and cardiovascular responses to swimming were examined in two species of pinniped, the harbor seal (Phoca vitulina) and the California sea lion(Zalophus californianus).
TL;DR: Experimental results indicate that the bird concentrations are responsible for the observed differences in seagrass communities surrounding islands that contain colonies, which are significant to the segrass ecosystem because many seagRasses in Florida Bay appear to be nutrient-limited.
Abstract: Colonies/roosts of piscivorous birds in Florida Bay, a subtropical estuary, concentrate nutrients by feeding away from their colonies/roosts and returning with food for young and to defaecate. Seagrass beds surrounding the colony islands were markedly different from those around similar islands that did not contain colonies. Seagrass standing crop was enhanced up to 200 m from bird colony islands compared with islands without colonies. The species of seagrass were also different at colonies, where Halodule wrightii and Ruppia maritima predominated in zones close to the colony islands. Around islands without colonies, only Thalassia testudinum was present. Experimental bird perches placed to stimulate concentrated bird presence produced changes in adjacent seagrass meadows that were similar to differences between islands with colonies and those without. Over 5 years, seagrass standing crop increased around the experimental perches, and species dominance shifted from T. testudinum to H. wrightii. No similar changes occurred at control locations. These experimental results indicate that the bird concentrations are responsible for the observed differences in seagrass communities surrounding islands that contain colonies. These enriched areas are significant to the seagrass ecosystem because many seagrasses in Florida Bay appear to be nutrient-limited. Demersal fish and invertebrate density and species richness have been shown to be a function of the seagrass standing crop and species composition, so the changes in seagrasses stimulated by localized bird concentrations have the capacity to alter the entire community structure.
TL;DR: Arginine supplemented diets had a short-lasting stimulatory effect on fish growth, an effect which could be detected only in fingerlings, and diets supplemented with arginine caused elevation of plasma insulin levels.
TL;DR: A batch chemiluminescence method for measurement of copper in seawater was developed from an existing flow injection technique as discussed by the authors, which was extremely sensitive with a detection limit in the range of 0.05-1.05 for 200 μl samples.
01 Jan 1991
TL;DR: In this paper, the authors examined many of the applications of artificial habitats in various aquatic environments and their biological impacts with reference to fisheries and their actual or possibile role in fishery management.
Abstract: This chapter examines many of the applications of artificial Iial)it;its i n various aquatic environments. The particular focus is on their I)iological irnpacts with reference to fisheries and their actual or possi1)le role in fishery management. Grouping artificial liabitats b y their primary users is a risetul wav to categorize the applications of these structures for analysis. Four principal categories recognized here include artisanal fisheries: sinall-scale commercial fisheries: recreational fisheries and diving; the replaceinent of 1iabit;it lost from shoreside development (mitigation): and enhanceinent of haliitat i n marine reserves. Examples of the uses and impacts of artificial 1ial)itats tor these categories are discussed i n the first section of this chapter. The second section focuses on the biological impacts of artificial habitats. Their much debated role i n aggregating production and creating new production is presented i n a 1)roader context. I t is proposed that artificial habitats may ( 1) redistribute excp1oital)le 1)iomass without increasing it or total stock size; (2) aggregate previously unexploited 1)iomass and increase exploitable biomass: or (3) increase totnl biomass. The discussion of each provides examples. Throughout the text. attention is given to identitying the eEectivc uses of artificial habitats i n fishery manageinent.
TL;DR: A variety of neoplasms and nonneoplastic hepatic lesions have been noted in winter flounder, Pseudopleuronectes americanus, from Boston Harbor, Massachusetts.
Abstract: A variety of neoplasms and nonneoplastic hepatic lesions have been noted in winter flounder, Pseudopleuronectes americanus, from Boston Harbor, Massachusetts. Inflammatory lesions include cholangii...
TL;DR: The ability of cortisol to increase gill Na+,K(+)-ATPase activity was examined in several salmonid species during development and found it had a limited but significant effect in chinook salmon fry, and had no effect in coho and Atlantic salmon fry.
TL;DR: Study results showed ionizing radiation capable of providing an extra, highly effective safeguard of shellfish sanitary quality when combined with traditional depuration treatment.
Abstract: Food processing by ionizing irradiation has been shown to be safe, effective and efficient for the purposes of food preservation, reduction of post-harvest storage losses, prolongation of shelf-life, pest disinfestation, inactivation of food-borne parasites, and destruction of microbial pathogens. The biological effectiveness of the process results from energizing of orbital electrons in the food target material. The energy transfer results in formation of free radicals which interact with essential macromolecules. Energy reserves in facultative anaerobes are stored preferentially as shellfish glycogens Lipids, require aerobic oxidation to reconstitute a suitable carbohydrate substrate to enter into the normal glycolytic pathway. Preservation of organoleptic qualities in radiation processed shellfish may also be related to their facultative anaerobic status. Irradiation presents distinct advantages for enhancing microbial quality in live shellfish when applied as an adjunct to existing sanitation programs. Potential abuse or mis-application of the process would result if, shellfish which did not meet established sanitary standards were allowed to be irradiation processed.
TL;DR: Flounder over the entire sampling area had increased levels of MN during the fall months of the year, probably influenced by the maternal cycle of gonadal maturation.
Abstract: Erythrocyte micronuclei (MN) frequencies of 280 winter flounder (Pseudopleuronectes americanus) from Chesapeake Bay to the southern Scotian Shelf including Long Island Sound were measured. The MN data were combined with data previously reported for 224 flounder and the combined data sets were analyzed. Incidences of MN were elevated sixfold in flounder from the New York Bight Apex as compared to frequencies for fish from the inshore Gulf of Maine and Block Island Sound, and twice those found in Georges Bank and Long Island Sound flounder. Inshore New Jersey fish had higher MN frequencies than those from inshore Gulf of Maine and Block Island Sound. The occurrence of MN in flounder from inshore Virginia was higher than in flounder from inshore Gulf of Maine and Block Island Sound. The large subset of stations from Long Island Sound indicated higher frequencies of MN in flounder from Hempstead and Shoreham as compared to most other sites in the Sound.
TL;DR: A review by Hindar et al. (1991) outlining the genetic consequences of aquaculture on natural fish populations and a more complete presentation of the papers read at the Loen symposium on interactions between cultured and wild Atlantic salmon.
TL;DR: The purpose of this study was to examine the potential effects of attaching radio transmitters and time-depth recorders (TDRs) on the foraging trip durations of Chinstrap Penguins breeding on Seal Island, South Shetland Islands, Antarctica.
Abstract: The behavior of seabirds away from the breeding colony is poorly understood. Recently, however, technologies have become available that promise to greatly expand our knowledge of the activity of birds at sea. Specifically, recent technological developments have led to studies of seabird diving (see Kooyman 1989), nest attendance (Wanless et al. 1985), foraging range and dive durations (Trivelpiece et al. 1986, Wanless et al. 1988a, Bengtson and Eberhardt 1989), and swimming velocity (Wilson and Bain 1984). These studies have relied upon electronic devices attached to the animal in some manner. Although essential in helping researchers to understand the activities of seabirds away from the nest, attached devices have the potential to alter the behavior of the animal under study either through the effects of increased drag or through the discomfort of instrument package attachment. This problem has recently been recognized by a number of investigators: (1) Wilson et al. (1986) found that velocity meters attached to African Penguins (Spheniscus demersus) decreased swimming velocity (inversely related to the device's cross sectional area), and potentially decreased net foraging trip energy gain. (2) Wanless et al. (1988b) found that Common Murres (Uria aalge) fitted with radio transmitters with external antennas spent less time in the colony, were absent for long periods, and delivered fewer prey to their young. (3) Wilson et al. (1989) found that the handling and trimming of tail feathers of Adelie Penguins (Pygoscelis adeliae) increased the duration of a single foraging trip, and the attachment of devices increased nest desertion and foraging trip duration (after 19 days of attachment). They also speculated that the diving depths of penguins may be affected by recorder attachment, with mean maximum depths decreasing with increasing device cross-sectional area. (4) Wilson and Bain (1984) found that African Penguins peck at devices when researchers are out of the sight of the birds, while Adelie Penguins may spend a considerable amount of time trying to remove a device (Wilson et al. 1990). Thus, studies of the effects of instruments on seabird behavior and performance are essential in interpreting results obtained by using them. The purpose of this study was to examine the potential effects of attaching radio transmitters and time-depth recorders (TDRs) on the foraging trip durations of Chinstrap Penguins breeding on Seal Island, South Shetland Islands, Antarctica.
TL;DR: The differences between the two species in their ability to utilize plant and animal material can be related to the resources available at their times of immigration.
TL;DR: The cytological and physiological changes which English sole underwent during the reproductive cycle were similar to those observed in other teleost species, however, certain distinctive features were observed, including a high prevalence of atresia of nonyolked oocytes.
TL;DR: In this article, the authors present an institutional framework for evaluating the multispecies/multifishery consequences of management decisions, and for articulating a clear set of compatible management goals for the various constituents.
Abstract: Fishery resources (fish, invertebrates, marine mammals, and reptiles) of the U.S. exclusive economic zone (EEZ, 3–200 nautical miles from the coast) are currently regulated under several pieces of key legislation enacted during the early 1970s. At that time fishery science was only beginning to appreciate the interactions among species and fisheries as being potential impediments to simultaneous realization of competitive management goals. Many of the important management problems currently faced in the EEZ are exacerbated by the incompatibility of regulations promulgated separately under these statutes, for what are ecologically- or technologically-related species. Reconciling the management of interacting species and fishermen will require an institutional framework for evaluating the multispecies/multifishery consequences of management decisions, and for articulating a clear set of compatible management goals for the various constituents. Traditional single-species biological reference points ...
TL;DR: Current information on systematics and morphology of larvae and juveniles of Sebastes is reviewed, as are intrageneric relationships among the many species of the genus.
Abstract: Current information on systematics and morphology of larvae and juveniles ofSebastes is reviewed, as are intrageneric relationships among the many species of the genus. Although some subgenera may remain after a cladistic analysis of the genus, others are probably artificial groupings of species that have convergent morphologies because of similar ecology. The relationships ofSebastes to other scorpaeniform fishes as well as the relationships of scorpaeniforms to other fishes are not resolved. Of the 102 species ofSebastes worldwide, 69 species have been illustrated as preflexion larvae, 35 as postflexion larvae and 65 as pelagic juveniles. Morphological characters of each of these stages were used to compare species, group them by similar appearances and then compare these groupings with existing subgenera. Some pigment patterns of preflexion larvae were rather consistent among species within certain subgenera but quite variable among species in other subgenera. Postflexion larvae fell into 11 groups based on pigment, head spines and body shape. These groups were not closely aligned with the subgeneric assignments of the component species. On the basis of pigment patterns of pelagic juveniles, six groups were evident, but the specific composition of these groups bore little resemblance to either the larval or subgeneric groups.
TL;DR: Sterols were identified from seven species of axenically cultured diatoms which may be used for oyster food and it appears that sterols from theOrder Centrales are 24β-oriented and those from the order Pennales are 24α-oriented.
TL;DR: Deploying scallops early in the season at temperatures lower than 14 °C appears to have no advantage relative to growth, and there was an inverse relationship between the size of the scallop and the density that affected growth.
TL;DR: The ontogenetic increase in agonism may result in school dispersal as fish move from the estuary into coastal waters, and may well reflect a shift in the costs versus the benefits of schooling as fish mature and become less vulnerable to predation.
Abstract: Although juvenile chum salmon,Oncorhynchus keta, are generally regarded as a schooling fish, when presented with a defensible point-source of food, some individuals abandon schooling, aggressively subordinate competitors, and monopolize food. When food is removed, fish gradually abandon solitary agonistic behaviors and return to schooling behavior. Agonism increases in frequency and intensity as juveniles age. The ability to alternate facultatively between schooling and solitary agonistic behavior may enable juvenile chum to respond to local patterns of food distribution and predation risk. The ontogenetic increase in agonism may result in school dispersal as fish move from the estuary into coastal waters, and may well reflect a shift in the costs versus the benefits of schooling as fish mature and become less vulnerable to predation.