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Feeding Studies On Three Species Of Fish From Tomales Bay, California, John Brezina

University of the Pacific Theses and Dissertations

The study of fish diets or feeding behavior is an important aspect in ecology. Analysis of fish stomach contents often provides data for determining resource utilization, feeding strategies, and overlaps in food items among and between species. Studies of fish diets could also be used for testing ecological theory or provide management procedures for fisheries if methods could be developed for minimizing competitive food utilizations by other fish and enhancing growth of exloited fish populations (Obrebski and Sibert 1977). In order to understand more about ecological communities and competitive predatory relationships of fish, more data are required on their diets …

The Relationship Of Sexual Dimorphism And Differential Predation To Sex Ratio In Leptochelia Dubia (Crustacea: Tanaidacea), Joseph Anthony Mendoza

University of the Pacific Theses and Dissertations

Leptochelia dubia is a dioecious tube-building tanais, which broods its young and exhibits marked sexual dimorphism. The species is widely distributed in the Pacific, Atlantic, Mediterranean and Indian Oceans, but to date there are no published accounts of its ecology. L. dubia is one of the most abundant of the small Crustacea in Tomales Bay, where it may attain densities of 30,000/m² in soft bottom communities.

A Response Surface Investigation Of The Larval Tolerances Of Three Spionid Polychaetes To Temperature, Salinity And Food Concentration, Alan Louis Hillyard

University of the Pacific Theses and Dissertations

Response surface techniques were used to investigate the tolerances of the planktonic larvae of three spionid polychaetes to a variety of temperature and salinity combinations. Two of the spionids were morphologically very similar members of the genus Boccar.dia., B. proboscidea and B. columbiana which occupy nearly identical geographic ranges. The other was Polydora giardi a common coinhabitant with B. columbiana. In addition a third independent parameter, food concentration, was added to the study of B. columbiana and P. giardi.

The larvae of the two Boccardia species were extremely euryhaline, in marked contrast to those of Polydora giardi which were confined …

Changes In Gall Bladder Bile Throughout Development In Rana Catesbeiana, Stanley G. Carson

University of the Pacific Theses and Dissertations

The present study of Rana catesbeinana includes an analysis of the following throughout the course of post-embryonic development: the change in GI tract length and weight; the relative surfactant activity of the bile; the change in major bile pigments. The most rapid and profound morphological and physiological transitions occur during the period of metamorphic climax. Because no information relative to change in anurans is available during this period, particular emphasis is placed upon the examination of individuals during metamorphic climax.

The Larval Development Of Pinnixa Longpipes (Lockington, 1877) (Brachyura: Pinnotheridae), Reared In The Laboratory, George Daryl Bousquette

University of the Pacific Theses and Dissertations

The Pea Crab, Pinniza longpies, is commensal with the tube building polychaete, Axiothella rubrocincta. This worm constructs U-shaped tubes in san-mud substrata of bays and estuaries along the Pacific coast. The pronounced lateral elongation and diminutive size of p. Longpies enable it to move easily in the narrow tube with the worm. The species has occasionally been found with other polychaetes, including Pectinaria and Pista. According to Schmitt et al (1973) Pinnixa longpies range from Tomales Bay to Laguna Beach in California. There are no published accounts regarding the biology of this commensal crab.

The present paper reports in detail …

Structure, Function, And Functional Morphology Of Mitra Idae Melvill 1893 And M. Catalinae Dall 1920, Terry L. West

University of the Pacific Theses and Dissertations

The morphology of the proboscis--particularly the epiproboscis, the feeding behavior, the function(s) of the epiproboscis, and the functional morphology of the epiproboscis, were studied in Mitra idea Melville and fi. catalinae Dall (Gastropoda: Neogastropoda; Mitridae.

In M. idae, the epiproboscis is an extensible muscular J-shaped rod which curves under the odontophore, and lies parallel to the longitudinal axis of the proboscis. A muscular external sheath encloses that portion of the epiproboscis which lies within the proboscis haemacoel; an invaginated muscular-epithelial internal sheath covers the ventral part of the epiproboscis. The dorsal part of the epiproboscis consists principally of longitudinal muscle; …

Alterations Of Central Dopamine Receptor Sensitivity In The Spontaneously Hypertensive Rat, John Richard Martin

University of the Pacific Theses and Dissertations

Since the time of the introduction of the spontaneously hypertensive rat (SHR) into medical research, several neuropharmacological studies have been performed on these animals which have been unrelated to their cardiovascular systems. A few of these studies have indicated possible abnormalities in the dopaminergic systems of SHR. Therefore the present study was undertaken to examine more closely the sensitivity of SHR to stimulation of their dopamine (DA) receptors.

Aerobic Capacity Of Intercollegiate Swimmers, James W. Stavosky

University of the Pacific Theses and Dissertations

Athletics competition represents the classical test of physical fitness or performance capacity. The individual’s performance is the combined result of the coordinated exertion and integration of a variety of functions. Intercollegiate swimmers are an example of highly trained individuals. Their swim training provides almost maximal activation of the aerobic process or the cardiovascular system. This high level of cardiovascular fitness and physical performance is the result of natural endowment plus the specific effects of swim training. INdividuals that began to train vigorously at an early age (as young as 8 years old) have shown increases in several aspects of aerobic …

An Epidemiological Study Of Human Toxoplasmosis In San Joaquin County, California, Peter Lund

University of the Pacific Theses and Dissertations

The major purpose of this study was to correlate certain personal characteristics of mothers and their offspring with the occurrence of toxoplasmosis serum antibodies in these women. As a byproduct, we determined the prevalence and incidence of toxoplasmosis in a particular subgroup of women in the Stockton, California area of San Joaquin County.

We had also hoped to provide early diagnostic services and follow up for any infected infants that we encountered. Unfortunately, follow up on these infants has been difficult largely due to the migrant habits of this particular group of seasonal farm workers. For these reasons this study …

Observations On The Reproductive Morphology Of Some California Spionid Polychaetes, F. Scott Mceuen

University of the Pacific Theses and Dissertations

This study considers the morphology of the sperm, nephridia, seminal receptacles, and gonads among a number of California spionid species. The data collected provide support for the general observation of other workers.

Sexual Dimorphism, Resource Partitioning And Intraspecific Aggression In Caprella Californica Stimpson, Ian D. Campbell

University of the Pacific Theses and Dissertations

The Caprellidae are a specialized suborder of Amphipoda, which are highly modified for a semisessile life. Caprellids exhibit direct development and brood their young. The suborder is exclusively marine and commonly found on filamentous algae, sea grasses and fouling communities. Most published works on caprellids have been primarily concern~d with systematics (Caine, 1974; Dougherty, 1943; Laubitz, 1970, 1972; McCain, 1968, 1975), although a few recent studies have dealt with ecology and ethology (Bynum, 1978; Caine, 1977; Keith, 1969, 1971; Lewbel, 1978; Saunders, 1966).

This study examines·spatial and temporal variations in distribution, abundance and population structure as well as describing intraspecific …

Effect Of Light On The Circadian Activity Rhythm Of The Slow Loris, Nycticebus Coucang, Jimmy F. Redman Jr.

University of the Pacific Theses and Dissertations

In this study, the locomotor activity of a nocturnal prosimian, the slow loris (Nycticebus coucang), was monitored under an experimentally varied light regime. During the process of reversing their day-night cycle, activity was monitored for a light-dark cycle roughly correlating to the external day-night, a free-running period in total darkness followed by a reversed day- night light regime.

Under constant conditions an endogenous cycle was shown to be present. During the artificial light regimes, locomotor activity became synchronized to the period of darkness.

A Quantitative Study Of The Morphology Of Normal, Hyperplastic, And Neoplastic Mammary Tissue In The Mouse, Elizabeth J. Hill

University of the Pacific Theses and Dissertations

This study intends to provide a quantitative and qualitative histological account of two aspects of mammary gland morphology. First, the normal mouse during different functional phases including inactivity, pregnancy, lactation and involution is presented. Second, the abnormal changes of mammary hyperplasia and neoplasia - both spontaneous and exogenous - are examined.

Interactions Between Portunion Conformis (Epicaridea: Entoniscidae) And Two Host Species, Francis Richard Gens

University of the Pacific Theses and Dissertations

Portunion conformis castrates the crab Hemigrapsus oregonensis. Piltz (1969) found P. conformis in both H. oregonensis and Hemigrapsus nudus. Kuris (1971) studied the interactions between P. conformis and H. oregonensis occurring in Bodega Bay, California. In the present study, interactions between this isopod and populations of both hosts in Tomales Bay, California, are described, including the influence of host species, sex and size on parasitic infestation and the effects of the parasites on secondary sexual characteristics of the hosts, as well as interactions between the effects of these variable.

Shore-Level Size Gradients In Tegula Funebralis (A. Adams) : Seasonal Changes Influenced By Interaction Of Predator Preference And Prey Behavior, Daniel Victor Markowitz

University of the Pacific Theses and Dissertations

Aspects of the Pisaster-Tegula interaction are re-examined. Reproductive portions of T. funebrallis populations are shown to be immune to seastar predation through a combination of predator preference for larger snails and a withdrawal behavior that favors the escape of smaller snails after capture by a seastar . Experimental addition of p. ochraaceus in winter causes changes in the intertidal distribution of T. funebralis similar to those observed during the summer increase in seastar numbers. It is suggested that these results supplant the hypothesis that lowered prereproductive mortality influences formation and maintenance of vertical size gradients in the lower intertidal .

Morphological Comparison Of Two Populations Of Peromyscus Maniculatus Gambelii From The Timberline Of Mt. Shasta, California, Craig Steven Marks

University of the Pacific Theses and Dissertations

The purpose of this study is to compare two populations of Peromyscus maniculatus gambelii from the same location, separated by about 80 years in an attempt to determine the degree of dissimilarity between them.

Digenetic Trematodes Of Marine Fishes From The Kuwaiti Coast Of The Arabian Gulf, Faiza Yousef Al-Yamani

University of the Pacific Theses and Dissertations

D~ring July and August 1978, 165 fishes belonging to 35 species in 19 families were collected from the Kuwaiti coast of the Arabian Gulf and examined for parasites. Nine digenetic trematodes including three new species and two new genera are described: (Hemiuridae) Opisthadena kuwaiti, n.sp. from Valamugil seheli, Lecithocladium bulbolabrum Reid, Coil and Kuntz, 1966 from Johnius aneus (new host record), 1· unibulbolabrum Fischthal and Thomas, 1971 from Rastralliger kanagurta (new host record), Clupenuroides sheemi n.g., n.sp, from Eleutheronema tetradactylum; (Angiodactylidae) Hexangium sigani Goto and Ozaki, 1929 from Sigartus oramin; (Pleorchiidae) Pleorchis arabicus n.sp. from Otolithes argenteus; (Opecoelidae) Helicometrina nimia …

The Ecology And Reproductive Cycle Of Pygospio Elegans Claparède (Polychaeta: Spionidae) From Tomales Bay, California, Debrah Lapp Armitage

University of the Pacific Theses and Dissertations

Pygospio elegans Claparede (1863) is a relatively small, inconspicuous intertidal Spionid polychaete (10 to 15 mm in length) having approximately 50 to 60 body segments. The species occurs in high intertidal sand flats along the central California coast.

Pygospio elegans is one of three species of the genus Pygospio, with the other being, P. california Hartman (1936) which is found only along the central California coast and P. dubia Munro (1930), from Antarctic seas. P. elegans is the most cosmopolitan of the three species (Clay, 1967; Light, 1978). The species has been recorded from both sides of the Atlantic Ocean; …

The Effect Of Body Size And Algal Suspension Density On Filtration Rate And Assimilation Efficiency Of Three Marine Mussels, Mytilus Californianus, Mytilus Edulis And Perna Canaliculus With Consideration Of The Growth Of Each Species, Thomas B. Mccormick Iii

University of the Pacific Theses and Dissertations

Rates of uptake of organic and inorganic suspended particulate material by suspension feeding bivalve molluscs have been studied since the nineteenth century (see Viallanes, 1892) . Studies have investigated molluscan feeding mechanisms, filtration capabilities, food assimilation and metabolism. The bulk of this work has been directed towards the mussel Mytilus edulis Linnaeus and the oyster Crassostrea virginica Gmelin (see reviews by Galtsoff, 1964; Ali, 1970; Jorgensen, 1975; 1976; and Winter, 1978). More recently the growth of mussels, oysters, clams and scallops has been quantitatively studied in controlled systems to assess the biological potential of these molluscs in an aquaculture setting …

The Foraging Strategy Of Diadema Antillarum (Philippi) (Echinodermata: Echinoidea), Robert Charles Carpenter

University of the Pacific Theses and Dissertations

Diadema antillarum (Philippi) is a common echinoid grazer in Caribbean reef areas. Field observations in st . Croix, u.s.v.r. an.d Disc. overy Bay, Jamaica and laboratory experiments demonstrate that these urchins have a strong feeding preference for algal turf. Seasonal variation in the abundance of this preferred food item results in increased incidences of live coral predation. Experimental manipulations demonstrate that over the short term food availability is more important than urchin density in determining prey item choice. Size and abundance data show an inverse relationship between urchin density and mean individual urchin size. There is also an inverse relationship …

Phasic Response Of Peripheral Nerves To Inflammation, Ralph Lee Myers

University of the Pacific Theses and Dissertations

Acute inflammation is associated with injury to tissues, whether it be from mechanical destruction, or from the introduction of a noxious substance into the tissue. Inflammation is a homeostatic process, adapted to neutralize harmful substances and restore injured tissue. Celsus (c. A.D. 178) provided the first documented characterization of inflammation. He recognized redness, heat, swelling and pain as the cardinal signs of the inflammatory reaction. Loss of function was later added to this list of symptons (Movat. 1971).

The Population Dynamics And Recruitment Pattern Of The Phoronid, Phoronopsis Viridis, Victoria Rolanda Starczak

University of the Pacific Theses and Dissertations

A dominant organism on intertidal Pacific Coast sandflats is the lophophorate Phoronopsis viridis Hilton. This suspension feeder builds a stiff, sandy tube, 3 mm wide and up to 20 cm long and usually lying within 6 cm of the surface (Johnson 1967a). Phoronopsis viridis is found over large areas and tidal ranges of sandflats in aggregate densities of over 21,000 phoronids per m² (Ronan 1978). On Lawson's Flat, the location of the present study, the areas of highest density of P. viridis have been known to persist for over 20 years (Steven Obrebski, personal communication).

The factors accounting for …

Larval Trematode Populations And Host-Parasite Interactions In Cerithidea Californica, John M. Emery

University of the Pacific Theses and Dissertations

Cerithidea california is examined to determine the fecundity of the parasitic trematode species in its gonad. Five species of trematodes are studied (Cloacitrema michiganensis, Euhaplorchis californiensis, Parorchis acanthus, Himasthia rhigedana, and Acanthoraryphium sp.). Their fecundity is determined by direct counts of rediae and estimation of the cercarial population. Correlations are shown for trematode numbers and snail size.

Incidences of infection are given with regard to site, snail size, and trematode species. Comparison is made between infection ratios of C. californica and another marsh snail, Batillaria zonalis.

Population Genetics Of The Genus Transennella (Bivalvia), William Gregory Rotz

University of the Pacific Theses and Dissertations

Genetic variation at twelve loci which code for enzymes and non-enzymatic protein has been studied by means of starch gel electrophoresis in two apparent species of the pelecypod genus Transennella, Variable allozymes include esterase, leucine aminopeptidase, malate dehydrogenase, phosphoglucose isomerase, tetrazolium oxidase, and nonenzymatic protein, Observed allele frequencies for these systems are in close agreement with Hardy-Weinberg expectations indicating that these protandric hermaphrodites are outbreeding. The genus is characterized by two distinct morphotypes which differ in shell shape and pigmentation. Genetic similarity (I) and genetic distance (D) statistics were computed for the two morphotypes and for two populations of each …