The effect of Kudoa paniformis infection on the reproductive effort of female Pacific hake

1998 ◽  
Vol 76 (12) ◽  
pp. 2285-2289 ◽  
Author(s):  
S A Adlerstein ◽  
M W Dorn
Keyword(s):  
Reproductive Effort ◽  
Detrimental Effect ◽  
Parasite Prevalence ◽  
Analysis Of Covariance ◽  
Fish Length ◽  
Intensity Of Infection ◽  
Oregon Coast ◽  
Merluccius Productus ◽  
The Pacific ◽  
Common Parasite

The effect of the myxosporidean Kudoa paniformis on the annual reproductive effort of the coastal stock of Pacific hake (Merluccius productus), on which it is a common parasite, is investigated. Female Pacific hake collected off the central Oregon coast in December 1988 were analyzed for prevalence and intensity of parasites. Reproductive effort was estimated by the number of yolked oocytes present in the ovaries immediately prior to spawning (potential annual fecundity), using the volumetric method. The effect of the parasite was evaluated through an analysis of covariance where fecundity was modeled as a function of fish length and parasite prevalence. An additional analysis of covariance evaluated the effect of the intensity of parasite infection on fecundity. Results show that the fecundity of Pacific hake is significantly reduced in the presence of K. paniformis infections and that the detrimental effect escalates with the intensity of infection. The potential effects on the population dynamics of the Pacific hake coastal stock are discussed.

Distribution of two species of Kudoa (Myxozoa: Multivalvulida) in the offshore population of the Pacific hake, Merluccius productus (Ayres, 1855)

1986 ◽  
Vol 64 (10) ◽  
pp. 2103-2110 ◽  
Author(s):  
Z. Kabata ◽  
D. J. Whitaker
Keyword(s):  
Vancouver Island ◽  
Distribution Range ◽  
Intensity Of Infection ◽  
Merluccius Productus ◽  
Parasite Distribution ◽  
The Pacific ◽  
Northerly Direction

Samples of pacific hake (Merluccius productus), a total of 581 fish, were collected along its distribution range from California to Vancouver Island. The fish were examined for prevalence and intensity of infection with Kudoa thyrsitis and K. paniformis (Myxozoa). Fish age 4+ (and older) were more heavily infected than those age 3+, the most heavily infected part of the fish being the dorsal musculature directly behind the head. Although the prevalence of infection with K. thyrsitis increased in a northerly direction, its intensity was markedly lower than the intensity of infection with K. paniformis. Fish of comparable age and size were twice as heavily infected with K. paniformis off California as those taken off Vancouver Island. Fish infected with K. thyrsitis appeared to show a much stronger reaction to the presence of the parasite by producing relatively more black pseudocysts than those infected with K. paniformis. Reasons for this fact and for the observed pattern of parasite distribution are discussed.

scholarly journals Genome Sequence of Lentisphaera araneosa HTCC2155T, the Type Species of the Order Lentisphaerales in the Phylum Lentisphaerae

2010 ◽  
Vol 192 (11) ◽  
pp. 2938-2939 ◽  
Author(s):  
J. Cameron Thrash ◽  
Jang-Cheon Cho ◽  
Kevin L. Vergin ◽  
Robert M. Morris ◽  
Stephen J. Giovannoni
Keyword(s):  
Genome Sequence ◽  
Type Species ◽  
Microbial Evolution ◽  
Unusual Property ◽  
Oregon Coast ◽  
The Pacific ◽  
Genome Content

ABSTRACT Information on the genome content of deeply branching phyla with very few cultured members is invaluable for expanding understanding of microbial evolution. Lentisphaera araneosa HTCC2155T was isolated from the Oregon coast using dilution-to-extinction culturing. It is a marine heterotroph found in surface and mesopelagic waters in both the Pacific and Atlantic oceans and has the unusual property of producing a net-like matrix of secreted exopolysaccharide. Here we present the genome sequence of L. araneosa HTCC2155T, importantly, one of only two sequenced members of the phylum Lentisphaerae.

Digenean parasite communities in flatfishes of the Scotian Shelf and southern Gulf of St. Lawrence

1982 ◽  
Vol 60 (11) ◽  
pp. 2804-2811 ◽  
Author(s):  
J. S. Scott
Keyword(s):  
Feeding Behavior ◽  
Feeding Habits ◽  
Stomach Contents ◽  
Parasite Prevalence ◽  
Winter Flounder ◽  
Fish Length ◽  
Pseudopleuronectes Americanus ◽  
Scotian Shelf ◽  
Yellowtail Flounder ◽  
Limanda Ferruginea

Prevalence of digenean parasites in four major flatfishes of the Scotian Shelf and southern Gulf of St. Lawrence, American plaice (Hippoglossoides platessoides), yellowtail flounder (Limanda ferruginea), witch flounder (Glyptocephalus cynoglossus), and winter flounder (Pseudopleuronectes americanus), is compared between hosts in relation to geographic distribution, season, feeding behavior, and fish length. The 13 parasite species indicate overlap of feeding habits among hosts but also considerable diversity in feeding behavior, supporting the evidence from examination of stomach contents. Prevalence of digeneans in different final hosts varied between geographic areas and may be used to characterize the populations of the comparatively sedentary flatfish populations. Seasonal variation in prevalence was consistent from area to area but differed between parasites, from the expected increase in summer in some, concomitant with increased feeding, to a winter increase in others, probably related to a seasonal change of diet. Fish length had little effect on parasite prevalence in yellowtail flounder and witch flounder but had a notable effect on plaice and winter flounder from the Gulf of St. Lawrence, again apparently related to change of diet.

Predicting deposition of debris flows in mountain channels

1990 ◽  
Vol 27 (4) ◽  
pp. 409-417 ◽  
Author(s):  
Lee E. Benda ◽  
Terrance W. Cundy
Keyword(s):  
Pacific Northwest ◽  
Debris Flows ◽  
Field Measurements ◽  
Coast Range ◽  
Oregon Coast Range ◽  
Oregon Coast ◽  
Aerial Photos ◽  
The Pacific ◽  
Channel Slope ◽  
Junction Angle

An empirical model for predicting deposition of coarse-textured debris flows in confined mountain channels is developed based on field measurements of 14 debris flows in the Pacific Northwest, U.S.A. The model uses two criteria for deposition: channel slope (less than 3.5°) and tributary junction angle (greater than 70°). The model is tested by predicting travel distances of 15 debris flows in the Oregon Coast Range and six debris flows in the Washington Cascades, U.S.A. The model is further tested on 44 debris flows in two lithological types in the Oregon Coast Range using aerial photos and topographic maps; on these flows only the approximate travel distance is known. The model can be used by resource professionals to identify the potential for impacts from debris flows. Key words: debris flow, deposition, travel, erosion.

Distribution of 65Zn In Tissues of Two Marine Crustaceans Determined by Autoradiography

1968 ◽  
Vol 25 (11) ◽  
pp. 2461-2466 ◽  
Author(s):  
F. A. Cross ◽  
S. W. Fowler ◽  
J. M. Dean ◽  
L. F. Small ◽  
C. L. Osterberg
Keyword(s):  
Pacific Ocean ◽  
Vertical Distribution ◽  
Food Web ◽  
Euphausia Pacifica ◽  
Oregon Coast ◽  
Marine Crustaceans ◽  
The Pacific ◽  
The Pacific Ocean ◽  
The Vertical Distribution

In the benthic amphipod Anonyx sp., and the euphausiid Euphausia pacifica Hansen, 65Zn accumulated from seawater was shown by autoradiography to be localized predominantly in the exoskeleton and interstitial spaces of the myofibrils. Also, the gut and hepatopancreas of Anonyx sp. and the eye of E. pacifica contained 65Zn. The presence of 65Zn in crustacean exoskeletons may affect the efficiency of transfer of 65Zn through the food web and the vertical distribution of 65Zn in the Pacific Ocean along the Oregon coast.

Regional Differences in Otolith Morphology of the Deep Slope Red Snapper Etelis carbunculus

1992 ◽  
Vol 49 (4) ◽  
pp. 795-804 ◽  
Author(s):  
M. Kimberly Smith
Keyword(s):  
Growth Rate ◽  
Regional Differences ◽  
Maximum Size ◽  
Dry Weight ◽  
French Polynesia ◽  
Red Snapper ◽  
Fish Length ◽  
Otolith Shape ◽  
The Pacific ◽  
Wide Range

Sagittal otoliths from four populations of the Pacific deep slope red snapper Etelis carbunculus Cuvier were compared using Fourier descriptors and other shape indices, linear proportions, and dry weight. Otoliths from Hawaii, Vanuatu, Fiji and French Polynesia and a small number from the Commonwealth of the Northern Marianas Islands (NMI) were examined. Regional shape and weight characteristics were distinguishable, despite the wide range of individual variation and limited available size range from some regions. Size-specific differences in otolith shape were found for the four regions for which a sufficient sample was available. Otoliths from Hawaii, French Polynesia, and NMI showed a significant shape affinity. Otoliths from Fiji and Vanuatu were similarly shaped and were distinct from those from the other three regions. Interregional otolith shape affinities for the stocks examined parallel similarities in maximum size and growth rate from the literature, suggesting that growth rate may influence otolith shape. Observed trends in otolith weight as a function of fish length support growth-related regional differences in otolith shape.

On Representing the Length Dependence of Acoustic Target Strengths of Fish

1979 ◽  
Vol 36 (12) ◽  
pp. 1490-1496 ◽  
Author(s):  
Kenneth G. Foote
Keyword(s):  
Analysis Of Covariance ◽  
Target Strength ◽  
Fish Length ◽  
Length Dependence ◽  
Dorsal Aspect ◽  
Significance Levels ◽  
Acoustic Target ◽  
Representation Method ◽  
Strength Functions ◽  
Linear Regressions

The problem of representing the length dependence of acoustic target strengths of fish is addressed by studying the legitimacy of merging target strengths that are inhomogeneous in species or frequency. The target strengths are of two kinds: maximum and averaged dorsal aspect target strengths, which are derived from measurements of gadoid target strength functions of three species at two ultrasonic frequencies. The target strengths are expressed variously according to unnormalized, wavelength-normalized and length-normalized schemes. Overall coincidences and coincidences of slopes among simple linear regressions of target strength on fish length, when segregated by target strength type and manner of representation, are investigated through analysis of covariance. Examination of computed significance levels demonstrates that merging of target strengths in species or frequency is generally unjustified and that no one representation method is superior to another in facilitating the merging of such data. The unnormalized representation is to be preferred when merging is justified because of its simplicity and avoidance of the frequency bias inherent in the normalized representations. The hypothesis of scaling of target strengths is refuted. Key words: target strength, regression, covariance analysis, fish abundance estimation

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