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Phylogeography Of A Vanishing North American Songbird: The Painted Bunting (Passerina Ciris), Connie Ann Herr Aug 2011

Phylogeography Of A Vanishing North American Songbird: The Painted Bunting (Passerina Ciris), Connie Ann Herr

UNLV Theses, Dissertations, Professional Papers, and Capstones

Studies of genetic variation within and between species can provide insights into their evolutionary history as well as important information for conserving biodiversity. An understanding of population processes can assist in the conservation of biodiversity by contrasting current versus historical patterns, and the processes that have generated these patterns. Genetic differentiation often coincides with significant geological or climatic changes that have shaped the sizes and locations of the species geographic range and altered the connectivity between populations over time. Phylogenetic and population genetic analyses can also provide a statistical framework for the investigation of how human processes such as habitat …


The Relations Among Laterality, Cortisol, And Approach-Avoidance Behavior In Garnett's Bushbaby (Otolemur Garnettii), David Burton Hanbury Aug 2011

The Relations Among Laterality, Cortisol, And Approach-Avoidance Behavior In Garnett's Bushbaby (Otolemur Garnettii), David Burton Hanbury

Dissertations

Many studies to date have demonstrated that approach and avoidance behaviors are processed asymmetrically in the brain and may be reflected in measures such as handedness. The purpose of this study was to extend work in primates on this topic to Garnett’s bushbaby, a prosimian species. Furthermore, to determine whether measures in addition to handedness relate to approach-avoidance behavior, lateralized differences in tympanic membrane temperature were assessed. Cortisol measures were also obtained to determine whether it was related approach-avoidance behavior and handedness. Eleven captive-born Garnett’s bushbabies (Otolemur garnettii) were evaluated for handedness and responsiveness to novelty. Moreover, the …


Ornamentation, Behavior, And Maternal Effects In The Female Northern Cardinal, Caitlin Winters Aug 2011

Ornamentation, Behavior, And Maternal Effects In The Female Northern Cardinal, Caitlin Winters

Master's Theses

This study seeks to understand the relationship between ornamentation, maternal effects, and behavior in the female Northern Cardinal (Cardinalis cardinalis). Female birds possess ornaments that indicate a number of important known aspects of quality and are usually costly to maintain. However, the extent to which female specific traits, such as maternal effects, are indicated is less clear. It is predicted by the Good Parent Hypothesis that this information should be displayed through intraspecific signal communication. Specifically, androgens and carotenoids are of interest in this study because both are linked to ornamentation, and are also important egg components that …


Biohydrogenation Of Docosahexaenoic Acid, Catherine Klein Aug 2011

Biohydrogenation Of Docosahexaenoic Acid, Catherine Klein

All Dissertations

Pathways of docosahexaenoic (DHA) biohydrogenation are not known; however, DHA is metabolized by ruminal microorganisms. The addition of DHA to the rumen alters the fatty acid profile of the rumen and milk and leads to increased trans-18:1 isomers, particularly trans-11 18:1 and 22 carbon fatty acids. This study included four in vitro experiments to identify if these are produced from DHA or if they come from other sources that are affected by DHA. In each experiment, ruminal microorganisms collected from a lactating Holstein cow were incubated in batch cultures for 0, 6, 24, and 48h and a uniformly 13C DHA …


Variation In Parenting Style In A Captive Group Of Western Lowlands Gorillas, Ana E. Fernandez Aug 2011

Variation In Parenting Style In A Captive Group Of Western Lowlands Gorillas, Ana E. Fernandez

Theses and Dissertations - UTB/UTPA

Parenting styles were examined in a group of western lowland gorillas to determine the relationship between parenting style and multiple births with a single individual. Another interest in this study was on varying ways that motherhood can be approached, with partial attention to the relationship between parenting style and social rank. Observational data was collected by means of focal animal sampling and used to analyze contact behaviors in mother-infant relationship. Results indicated that parenting style stayed consistent within the same mother, but different between mothers.


Effects Of Ergot Alkaloids And Antioxidants On Bovine Sperm Motility, Ryan James Page Aug 2011

Effects Of Ergot Alkaloids And Antioxidants On Bovine Sperm Motility, Ryan James Page

Graduate Theses and Dissertations

The studies that comprise this thesis were performed in an attempt to identify and eliminate stressful conditions that may lead to infertility in the male bovine. The first project was performed to determine if ergot alkaloids directly affect bovine sperm motility. Percentage of motile spermatozoa was affected (P = 0.015) by a three-way interactions between time, concentration, and alkaloid. Ergotamine and dihydroergotamine decreased (P = 0.01) sperm motility in a concentration and time dependant manner and ergonovine had a minimal effect on overall sperm motility. The number of static spermatozoa also was affected (P < 0.01) by a three way interaction and increased as ET and DHET concentrations increased. Percentages of progressively motile and rapidly motile spermatozoa decreased (P < 0.01) in a two way interaction between alkaloid and concentration. Overall, sperm motility was decreased by ET and DHET. Furthermore, the qualities of motility as represented by progressive, rapid, path velocity (VAP), progressive velocity (VSL), track speed (VCL), beat frequency (BCF), lateral amplitude (ALH), straightness (STR), elongated, and area were decreased by those alkaloids. These data verify that ergot alkaloids commonly found in toxic tall fescue are detrimental to bovine spermatozoa. In the second study two antioxidants (alpha-tocopherol and ascorbic acid) were added to bovine sperm culture media and cryopreservation extender. The antioxidant capabilities of these two vitamins could help reduce free radical production and help preserve sperm viability. There was an interactive effect between ascorbic acid concentration and storage method on the bovine sperm motility characteristics: motile, progressive, rapid, track speed (VCL), and straightness (P < 0.05). A bull by ascorbic acid interaction (P < 0.05) was observed for motile, progressive, rapid, path velocity (VAP), progressive velocity (VSL), and VCL characteristics. Alpha tocopherol had no affects on sperm motility characteristics. Lipid peroxidation was affected (P < 0.01) by bull and ascorbic acid. Malondialdehyde concentrations for ascorbic acid treatments (0, 5, 10, 20 mM) were 3.25, 4.2, 2.96, and 2.15 ìM respectively. Results from the second study indicate that the addition of ascorbic acid may reduce sperm motility, but help prevent lipid peroxidation.


Investigation Of In-Package Ozonation: The Effectiveness Of Ozone To Inactive Salmonella Enteritidis On Raw, Shell Eggs, Austin Donner Jul 2011

Investigation Of In-Package Ozonation: The Effectiveness Of Ozone To Inactive Salmonella Enteritidis On Raw, Shell Eggs, Austin Donner

The Journal of Purdue Undergraduate Research

Food production, handling, and distribution practices pose a constant threat to the quality and safety of food products. The objective of this research is to evaluate an innovative in-package ozonation process to reduce Salmonella enteritidis on raw, shell eggs. Previous research has shown that in-package ozonation eliminates contaminants from outside sources, reduces pathogens, and extends shelf life. In this study, raw, shell eggs were inoculated with Salmonella enteritidis and exposed to ozonation treatment. Microbial recoveries were then tested to determine bacterial reductions. Measurements included: relative humidity (34 percent at 5oC), surface temperatures (oC), ozone concentrations, bacterial …


Role Of Dopamine In Impulse Control, Paul Rafael Sabandal ^, Young-Cho Kim, Kyung-An Han * Jul 2011

Role Of Dopamine In Impulse Control, Paul Rafael Sabandal ^, Young-Cho Kim, Kyung-An Han *

COURI Symposium Abstracts, Summer 2011

No abstract provided.


Oat Snp Marker Discovery And Mapping Based On 454 Pyrosequencing Of Genome-Reduced Avena Magna Murphy Et Terrell, Rachel Rebecca Redman Jul 2011

Oat Snp Marker Discovery And Mapping Based On 454 Pyrosequencing Of Genome-Reduced Avena Magna Murphy Et Terrell, Rachel Rebecca Redman

Theses and Dissertations

The size and complexity of the oat genomes (Avena L., x = 7) have made genetic studies, including the discovery of molecular markers, difficult. Recent attention to these species has resulted in the development of many DArT -based markers in the tetraploid A. magna Murphy et Terrill (2n = 28, CCDD genomes), along with numerous RFLP's, SSR's, DArT's, and EST-based SNPs in hexaploid A. sativa L. (2n = 42, AACCDD). Here we report the first SNP markers for tetraploid oat based on genome reduction and high-throughput pyrosequencing in two inbred lines of A. magna: A-169 (wild) and Ba …


Marker Discovery In Allotetraploid Cotton Using 454 Pyrosequencing, Robert L. Byers Jul 2011

Marker Discovery In Allotetraploid Cotton Using 454 Pyrosequencing, Robert L. Byers

Theses and Dissertations

A narrow germplasm base and a complex allotetraploid genome have historically made the discovery of single nucleotide polymorphism (SNP) markers difficult in cotton (Gossypium hirsutum). We conducted a genome reduction experiment to identify SNPs from two accessions of G. hirsutum and two accessions of G. barbadense. Approximately 2 million sequence reads were assembled into contigs with an N50 of 508 bp and analyzed for SNPs. A total of 11,834 and 1,679 SNPs between the accessions G. hirsutum and G. barbadense, respectively, were identified with highly conservative parameters (a minimum read depth of 8x at each SNP …


Reproductive Success And Soil Seed Bank Characteristics Of Astragalus Ampullarioides And A. Holmgreniorum (Fabaceae): Two Rare Endemics Of Southwestern Utah, Allyson B. Searle Jul 2011

Reproductive Success And Soil Seed Bank Characteristics Of Astragalus Ampullarioides And A. Holmgreniorum (Fabaceae): Two Rare Endemics Of Southwestern Utah, Allyson B. Searle

Theses and Dissertations

Astragalus ampullarioides and A. holmgreniorum are two rare endemics of southwestern Utah. Over two consecutive field seasons (2009-2010) we examined pre-emergent reproductive success, based on F/F and S/O ratios, from populations of both Astragalus ampullarioides and A. holmgreniorum, estimated the density of the soil seed bank of A. holmgreniorum as a measure of potential post-emergent reproductive success, and estimated seed persistence within the soil seed bank. Fruit/flower (F/F) ratios and seed/ovule (S/O) ratios varied significantly between populations and among years in both species, and showed low reproductive output in both taxa. In Astragalus ampullarioides F/F and S/O were 0.06±0.01 …


Mutual Mother–Offspring Vocal Recognition In An Ungulate Hider Species (Capra Hircus), Elodie F. Briefer, Alan G. Mcelligott Jul 2011

Mutual Mother–Offspring Vocal Recognition In An Ungulate Hider Species (Capra Hircus), Elodie F. Briefer, Alan G. Mcelligott

Sentience Collection

Parent–offspring recognition can be essential for offspring survival and important to avoid misdirected parental care when progeny mingle in large social groups. In ungulates, offspring anti-predator strategies (hiding vs. following) result in differences in mother–offspring interactions, and thus different selection pressures acting on the recognition process during the first weeks of life. Hider offspring are isolated and relatively stationary and silent to avoid detection by predators, whereas follower offspring are mobile and rapidly mix in large social groups. For these reasons, hiders have been suggested to show low offspring call individuality leading to unidirectional recognition of mothers by offspring and …


Effects Of Dietary Distillers Dried Grains With Solubles And Soybean Meal On Extruded Pellet Characteristics And Growth Responses Of Juvenile Yellow Perch, Travis W. Schaeffer, Michael L. Brown, Kurt A. Rosentrater Jul 2011

Effects Of Dietary Distillers Dried Grains With Solubles And Soybean Meal On Extruded Pellet Characteristics And Growth Responses Of Juvenile Yellow Perch, Travis W. Schaeffer, Michael L. Brown, Kurt A. Rosentrater

Natural Resource Management Faculty Publications

A 126-d feeding trial was performed to investigate graded combinations of distillers dried grains with solubles (DDGS) and soybean meal (SBM) in diets formulated for yellow perch Perca flavescens. Six experimental diets contained DDGS and SBM at 0 and 31.5% (dry matter basis), respectively (0/31.5 diet), 10 and 26% (10/26), 20 and 20.5% (20/20.5), 30 and 15% (30/15), 40 and 9.5% (40/9.5), and 50 and 4% (50/4) to obtain similar levels of crude protein (mean ± SE = 30.1 ± 0.2%), crude lipid (16.7 ± 0.7%), and digestible energy (13.5 ± 0.2 kJ/g). Fourteen fish (initial individual weight = 19.1 …


Phylogeography Of The Reef Fish Cephalopholis Argus(Epinephelidae) Indicates Pleistocene Isolation Across The Indo-Pacific Barrier With Contemporary Overlap In The Coral Triangle, Michelle R. Gaither, Brian W. Bowen, Tiana-Rae Bordenave, Luiz A. Rocha, Stephen J. Newman, Juan A. Gomez, Lynne Van Herwerden, Matthew T. Craig Jul 2011

Phylogeography Of The Reef Fish Cephalopholis Argus(Epinephelidae) Indicates Pleistocene Isolation Across The Indo-Pacific Barrier With Contemporary Overlap In The Coral Triangle, Michelle R. Gaither, Brian W. Bowen, Tiana-Rae Bordenave, Luiz A. Rocha, Stephen J. Newman, Juan A. Gomez, Lynne Van Herwerden, Matthew T. Craig

Fisheries Research Articles

Background

The Coral Triangle (CT), bounded by the Philippines, the Malay Peninsula, and New Guinea, is the epicenter of marine biodiversity. Hypotheses that explain the source of this rich biodiversity include 1) the center of origin, 2) the center of accumulation, and 3) the region of overlap. Here we contribute to the debate with a phylogeographic survey of a widely distributed reef fish, the Peacock Grouper (Cephalopholis argus; Epinephelidae) at 21 locations (N = 550) using DNA sequence data from mtDNA cytochrome b and two nuclear introns (gonadotropin-releasing hormone and S7 ribosomal protein).

Results

Population structure was significant …


Genome Snapshot And Molecular Marker Development In Penstemon (Plantaginaceae), Rhyan B. Dockter Jul 2011

Genome Snapshot And Molecular Marker Development In Penstemon (Plantaginaceae), Rhyan B. Dockter

Theses and Dissertations

Penstemon Mitchell (Plantaginaceae) is one of the largest, most diverse plant genera in North America. Their unique diversity, paired with their drought-tolerance and overall hardiness, give Penstemon a vast amount of potential in the landscaping industry—especially in the more arid western United States where they naturally thrive. In order to develop Penstemon lines for more widespread commercial and private landscaping use, we must improve our understanding of the vast genetic diversity of the genus on a molecular level. In this study we utilize genome reduction and barcoding to optimize 454-pyrosequencing in four target species of Penstemon (P. cyananthus, …


Multistate Mark-Recapture Analysis Reveals No Effect Of Blood Sampling On Survival And Recapture Of Eastern Kingbirds (Tyrannus Tyrannus), Lucas J. Redmond, Michael T. Murphy Jul 2011

Multistate Mark-Recapture Analysis Reveals No Effect Of Blood Sampling On Survival And Recapture Of Eastern Kingbirds (Tyrannus Tyrannus), Lucas J. Redmond, Michael T. Murphy

Biology Faculty Publications and Presentations

The experimentally supported and prevailing opinion is that blood sampling has few to no long-term effects on survival of birds when conducted properly, and blood sampling has become a vital addition to the toolbox of many ornithologists. However, many of the studies that concluded that blood sampling had negligible effects on birds used approaches that did not account for temporary emigration and probability of capture. To date, the only study to have done so found that blood sampling had a strong negative effect on survival. We conducted a mark–recapture analysis of 8 years of banding and bleeding data on Eastern …


Invertebrate Zooid Polymorphism: Hydractinia Polyclina And Pagurus Longicarpus Interactions Mediated Through Spiralzooids, Charlotte M. Regula-Whitefield Jul 2011

Invertebrate Zooid Polymorphism: Hydractinia Polyclina And Pagurus Longicarpus Interactions Mediated Through Spiralzooids, Charlotte M. Regula-Whitefield

All Theses And Dissertations

Evaluating the net interaction between symbionts can be challenging when one participant is a colonial animal with polymorphic zooids, because each zooid type has unique functions. The colonial hydroid Hydractinia polyclina has three distinct zooid types, each of which contributes particular components to the interaction with host hermit crabs. Of these three zooid types, the function of spiralzooids is not well understood. Previously, spiralzooids have been proposed to contribute a strong negative interaction component by directly reducing their host hermit crab’s reproductive output. However, this hypothesis is not supported by past or current data. I propose that spiralzooids instead function …


The Effects Of Social Context And Cache Survival On Pinyon Jay Caching Behavior, Christine L. Keefe Jul 2011

The Effects Of Social Context And Cache Survival On Pinyon Jay Caching Behavior, Christine L. Keefe

School of Biological Sciences: Dissertations, Theses, and Student Research

I examined how pinyon jays (Gymnorhinus cyanocephalus) assess and determine the risk of pilferage to their caches. Jays were allowed to cache in an open room while alone or while being observed by a conspecific. In a counterbalanced design, jays cached in the opposite treatment once they had finished recovering their caches. I compared birds’ behaviors between treatments in order to determine whether jays consider the presence of an observer in measuring the local competitive environment. Once all jays had completed alone- and observed- treatments, I ran the experiment once more to determine if individuals were consistent in …


Exploring Sources Of Selection On The Multimodal Courtship Displays Of Two Sister Species Of Wolf Spiders: Schizocosa Crassipalpata And Schizocosa Bilineata, Mitch D. Bern Jul 2011

Exploring Sources Of Selection On The Multimodal Courtship Displays Of Two Sister Species Of Wolf Spiders: Schizocosa Crassipalpata And Schizocosa Bilineata, Mitch D. Bern

School of Biological Sciences: Dissertations, Theses, and Student Research

We examined multiple sources of selection on the multimodal courtship display of two sister species of wolf spiders, Schizocosa crassipalpata and Schizocosa bilineata. We first experimentally altered body condition in these two species by employing divergent diet treatments. We then tested for differences in adult male seismic courtship displays, visual courtship displays, and foreleg morphology; as well as adult female foreleg morphology. We then simultaneously examined both content and efficacy-based sources of selection on the visual and seismic multimodal courtship display of both species by conducting mate choice trials with high and low diet individuals across manipulated signaling environments …


The Complexities Of Wolf Spider Communication: Exploring Courtship Signal Function In Rabidosa Rabida, Dustin J. Wilgers Jul 2011

The Complexities Of Wolf Spider Communication: Exploring Courtship Signal Function In Rabidosa Rabida, Dustin J. Wilgers

School of Biological Sciences: Dissertations, Theses, and Student Research

Evidence of signal complexity is seemingly pervasive across animal communication systems. Exploring signal function may provide insight into how these displays evolved and are maintained. This dissertation examines the courtship signal function in a grassland wolf spider. Rabidosa rabida lives in an extremely complex environment, and males use complex displays incorporating both visual and seismic modalities. Using several approaches I provide insight into the content and efficacy of the various signal components, as well as how variation in these displays influence female mating decisions in isolation and combined.

First, I manipulated male and female body condition using diet quantity manipulations …


Patterns Of Transience, Sex Bias, And Body Mass In Open-Habitat Rodent Populations, Stephen Edward Rice Jul 2011

Patterns Of Transience, Sex Bias, And Body Mass In Open-Habitat Rodent Populations, Stephen Edward Rice

Biological Sciences Theses & Dissertations

Rodents are assumed to live their lives in circumscribed (natal) areas with males being more prone to disperse than females and juveniles more prone to disperse than adults. To test these assumptions we examined the initial captures of geographic populations of hispid cotton rat, meadow vole, prairie vole, and marsh rice rat obtained through capture-mark-recapture methods. Capture records were obtained from Kansas and Illinois from long-term studies, and through live-trapping in Chesapeake, Virginia. I evaluated proportions of residents and transients, adults and juveniles, and males and females for significant differences among seasons, years, and geographic locations. The overall body masses …


Rats As Forest Pests In Southeastern Virginia: Girdling By The Hispid Cotton Rat Sigmodon Hispidus As A Significant Source Of Mortality Of Loblolly Pines (Pinus Taeda) In A Successional Pine Forest, Robyn M. Nadolny Jul 2011

Rats As Forest Pests In Southeastern Virginia: Girdling By The Hispid Cotton Rat Sigmodon Hispidus As A Significant Source Of Mortality Of Loblolly Pines (Pinus Taeda) In A Successional Pine Forest, Robyn M. Nadolny

Biological Sciences Theses & Dissertations

The hispid cotton rat (Sigmodon hispidus) is a common field rodent throughout the southeastern US, where volunteer loblolly pine trees (Pinus taeda) invade open space and begin the process of ecological succession from field to pine forest. Recent analysis of the diet of S. hispidus indicates that loblolly pine bark is stripped and eaten during the winter months. In this study, we explored the extent of rodent girdling on a 1.23 ha grid in a successional pine forest in southeastern Virginia. During the winter of 2005 we observed damage to 65% of trees in our study area, with 98% …


Preserving Field Notes On Songbird Biology At Indiana University, Eric Snajdr, Ellen D. Ketterson Jun 2011

Preserving Field Notes On Songbird Biology At Indiana University, Eric Snajdr, Ellen D. Ketterson

Val Nolan Jr. (1976 Acting; 1980 Acting)

No abstract provided.


Transcriptome Characterization And Polymorphism Detection In Subspecies Of Big Sagebrush (Artemisia Tridentata), Prabin Bajgain Jun 2011

Transcriptome Characterization And Polymorphism Detection In Subspecies Of Big Sagebrush (Artemisia Tridentata), Prabin Bajgain

Theses and Dissertations

Big sagebrush (Artemisia tridentata) is one of the ecologically most important shrub species in western North America. The species serves as a major source of food and habitat for the near-threatened sage grouse and various other fauna. Habitat loss due to a combination of disturbances followed by establishment of invasive plant species is considered as a serious threat to sustainability of the big sagebrush ecosystem. Because of its importance, restoration of this species is very crucial to those dependent on big sagebrush community. However, restoration of big sagebrush carried out by using diverse seed source can lead to …


The Effect Of Calving Season And Wintering System On Cow And Calf Performance And Economics From Conception Through Finishing And The Effect Of Supplementing Dried Distillers Grains To Calves In Forage Based Systems, William Griffin Jun 2011

The Effect Of Calving Season And Wintering System On Cow And Calf Performance And Economics From Conception Through Finishing And The Effect Of Supplementing Dried Distillers Grains To Calves In Forage Based Systems, William Griffin

Department of Animal Science: Dissertations, Theses, and Student Research

Three experiments were conducted to determine the effect of calving season and cow wintering systems on cow and calf performance and economics from conception to slaughter, the effect of supplementing steers dried distillers grains while grazing cool season dominated meadow, and a meta-analysis was conducted to determine the effect supplementing dried distillers grains to cattle in forage based growing systems.  In the first experiment, cows were bred to calve in spring, summer or fall.  Calves from each system were managed as calf-feds or yearlings and followed through finishing.  Altering calving season impacted cow BW and BCS but did not affect …


Diel Distribution And Movement Of Sound Scattering Layer In Kuroshio Waters, Northeastern Taiwan, Ming-An Lee, Ming-Hsiu Chao, Jinn-Shing Weng, Yang-Chi Lan, Hsueh-Jung Lu Jun 2011

Diel Distribution And Movement Of Sound Scattering Layer In Kuroshio Waters, Northeastern Taiwan, Ming-An Lee, Ming-Hsiu Chao, Jinn-Shing Weng, Yang-Chi Lan, Hsueh-Jung Lu

Journal of Marine Science and Technology–Taiwan

A 26-hr acoustic observation was carried out on board of the “Ocean Research II” in the Kuroshio waters at 123°09.027'E, 25°05.019'N from August 4 to 5, 2007. Acoustic volume scattering strengths (SVs) were collected by a scientific echo sounder (EK500, 38 kHz) and diel variations of sound scattering layer were analyzed. The maximum SV of surface scattering layers (SSL) around 20~80 m was observed after dawn, and mean SVs of SSL in nighttime was about -68 dB, 8 dB higher than that of daytime. Two deep scattering layers (DSL) were found in daytime at depth of 400~500 m and 600~700 …


Measurement And Modeling Of Three Dimensional Target Strength Of Fish For Horizontal Scanning Sonar, Muhammad Kurnia, Kohji Iida, Tohru Mukai Jun 2011

Measurement And Modeling Of Three Dimensional Target Strength Of Fish For Horizontal Scanning Sonar, Muhammad Kurnia, Kohji Iida, Tohru Mukai

Journal of Marine Science and Technology–Taiwan

This paper discusses the three-dimensional target strength (3DTS) of fish for a horizontal scanning sonar. Experiments were conducted in a tank using a defrosted Japanese mackerel. Measurements were made by changing the horizontal incident angle of a 50 kHz acoustic beam and the pitch angle of a tethered fish. Following the experiment, morphological characteristics, including the swimbladder size and shape, were measured using soft X-ray and digitized. The theoretical 3DTS was estimated using the prolate spheroid model and compared with the measured 3DTS. Results showed that the TS strongly depended on the fish orientation. The maximum and minimum TS were …


Spatial Estimation Of Euphausiid Biomass Along The Pacific Coast Of Eastern Hokkaido, Japan In Early Summer Of 2008, Naoki Tojo, Kenji Minami, Ryuichi Matsukura, Yohei Kawauchi, Tetsuichiro Funamoto, Masayuki Chimura, Akira Nishimura, Kazushi Miyashita Jun 2011

Spatial Estimation Of Euphausiid Biomass Along The Pacific Coast Of Eastern Hokkaido, Japan In Early Summer Of 2008, Naoki Tojo, Kenji Minami, Ryuichi Matsukura, Yohei Kawauchi, Tetsuichiro Funamoto, Masayuki Chimura, Akira Nishimura, Kazushi Miyashita

Journal of Marine Science and Technology–Taiwan

This study focused on euphausiid distribution and biomass estimation over the coastal shelf of the Pacific coast of Hokkaido Japan in early summer 2008. Acoustic data were obtained in both day (6:00-18:00) and night (18:00-6:00) using a quantitative echosounder (EK60, Simrad) with two frequencies (120 and 38 kHz). Echoes of euphausiids were specified based on the ΔMVBS, calculated with seasonal theoretical target strength of Euphausia pacifica. The best-fit kriging models were used to quantitatively interpolate euphausiid distribution. The detected euphausiid biomass reached 38,278 t (> 15 gWWm-2), suggesting abundant prey for large fishes over study area. On the other hand, …


Technology Evolution And Advances In Fisheries Acoustics, Dezhang Chu Jun 2011

Technology Evolution And Advances In Fisheries Acoustics, Dezhang Chu

Journal of Marine Science and Technology–Taiwan

Application of sonar technology to fisheries acoustics has made significant advances over recent decades. The echosounder systems evolved from the simple analog single-beam and single-frequency systems to more sophisticated digital multi-beam and multi-frequency systems. In this paper, a brief review of major technological advances in fisheries acoustics is given, as well as examples of their applications.


Echo Integration Near The Seabed, Masahiko Furusawa Jun 2011

Echo Integration Near The Seabed, Masahiko Furusawa

Journal of Marine Science and Technology–Taiwan

The echo integration (EI) method has long been used for fish abundance estimations. The method is applicable to any type of fish distribution and the analysis is easy to perform by advanced software. For fish near the seabed, however, sometimes it is difficult to perform an analysis because of so-called dead zones. In this paper, the EI near the seabed is considered, reviewing past studies and introducing some new ideas such as an unsampled zone. For the consideration, close inspection of the EI theory is necessary and a section is devoted to the purpose. As an application of the EI …