M.S. - Zoology
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Item The maturation and spawning of the bigeye tuna, Parathunnus sibi, in the western equatorial, central equatorial, and Hawaiian areas of the Pacific ocean([Honolulu], 1954) Yuen, Heeny Shew HeenInformation on the life history of the bigeye tuna, Parathunnus sibi. This paper will aim at finding the time and place of spawning, the age of maturity, the number of eggs produced at one spawning, and the number of times a fish spawns in a season.Item Studies on the biology and ecology of some Indo-Pacific Terebra from Eniwetok Atoll([Honolulu], 1966) Miller, Bruce AlvinSome aspects of the biology and ecology of fourteen species of Indo-Pacific Terebra collected at Eniwetok Atoll have been studied. Terebra exhibit both external and internal sexual dimorphism. Mating was observed and described, and differences in the sex ratio and spawning season are discussed. Terebra are negatively photosensitive to white light, but are unaffected by low intensity red light. Endogenous rhythms of locomotory activity are exhibited by the species of Terebra studied. The functional anatomy of the terebrid digestive system is presented, and the feeding process is described. Differences are noted between T. maculata and T. crenulata in the nature of the prey, the time of feeding, and the percent of the population feeding each day. The shallow water sand community structure of Eniwetok Atoll is examined.Item The Food and Feeding Habits of the Kumu, Parupeneus porphyreus(University of Hawai'i, Honolulu, 1969-02-01) Mahi, Cherrie AnnThe kumu, Parupeneus porphyreus, is one of the most valuable reef fishes in Hawaii. It is a member of the goatfish family (Mullidae) and is endemic to Hawaii. One hundred and ninety-eight specimens, ranging in size from 31 to 306 mm, were collected from four areas around Oahu, Hawaii. Collections were made from July through November, 1968. The anatomy and the contents of the digestive systems were examined The digestive system is short. The stomach is V-shaped with a bulbiform pylorus. There are 20 pyloric caeca. The instestine has one siphonal loop. Transforming specimens differ in having a shorter, straight intestine. They also have sharper pharangeal teeth and longer gill rakers than do the adults. Occurrence of food in the entirA gastrointestinal tract was used in ranking relative fullness. These rankings, compared with time of capture, indicated feeding was nocturnal or crepuscular among larger fish (only very young kumu fed during the day) and that food passed through the alimentary canal within 19 hours. Twenty-three food items were identified; 12 of them occurred in >10% of the guts. Crabs were the most important food, followed by other crustaceans (copepods, isopods, other decapods) and other invertebrates. Sand occurred in 57% of the specimens. An extensive comparison of food items vs. fish size demonstrated various relationships. Although crabs were eaten by nearly all fish, only large kumu ate Stenopus and other fish, and only small kumu ate copepods and isopods.Item Aspects of the biology and ecology of Cypraea moneta at Eniwetok Atoll, Marshall Islands(1971) Renaud, Maurice L.; ZoologyItem Aspects of the age and growth, reproduction, and diet of the millet-seed butterflyfish, Chaetodon miliaris (Pisces: Chaetodontidae), an Hawaiian endemic(University of Hawai‘i, Honolulu, 1975-12) Ralston, StephenAspects of the growth, reproduction and diet of Chaetodon miliaris, the millet-seed butterflyfish, were studied in an effort to characterize populations of fish exploited by the aquarium fish industry. Age determinations were accomplished by examination of daily growth rings within otoliths. Age estimates were corroborated by growth experiments, analysis of a size-frequency distribution, and the determination of the onset of reproductive maturity. Estimates of the duration of the larval tholichthys stage were also obtained from study of the otoliths. The sex ratio of £. miliaris was 1:1 and individuals matured after one year of growth. The spawning season extended from November through Hay but peaked in February and March. No lunar influence on spawning was found. Estimates of fecundity were high and indicated a relatively large investment in reproduction. Chaetodon miliaris is broadly opportunitistic in its diet, however it feeds principally on zooplankton in the water column. The diet of individual fish varied as a function of the time of year, the collection location and the size of the fish. Individuals from Kaneohe Bay, Oahu, were small and appeared to be reproductively inactive when compared to fish from other areas. Dietary deficiencies are postulated as causing these differences. The overexploitation of populations of the millet-seed butterflyfish as a fisheries resource is improbable due to its fast growth, high fecundity, and the existence of refuge populations.Item The responses of two species of hermatypic corals and their zooxanthellae to changes in light intensity(University of Hawaii at Manoa, 1976-12) Redalje, Randi C.The photosynthetic capabilities of zooxanthellae at various depths and light levels have been investigated by a number of workers (Barnes & Taylor, 1973; Wethey & Porter, 1976; Jeffrey & Haxo, 1968; Halldal, 1968). The relationship between photosynthesis and light has been described as a rectangular hyperbola. The Michaelis-Menton equation has often been fitted to the photosynthesis-light relationship for the coral-zooxanthellae complex as well as for phytoplankton (Wet hey & Porter, 1976; Caperon & Meyer, 1972; Steeman-Nielsen & Jorgensen, 1968). Wethey & Porter (1976) compared the photosynthetic rates of "sun" and "shade" corals. The terms "sun" and "shade" corals refer to corals collected from environments subjected to high and low light intensities respectively. Colonies of the foliaceous species, Pavona praetoria, collected from 10 meters, and 25 meters depth at Enewetak were compared. The maximum photosynthetic rate was higher for the 10 m. individuals than for the 25 m. corals. The "shade" corals, however (25 m.) were found to be light saturated at a lower light intensity than the shallow water colonies. This indicates that the "shade" corals are making efficient use of their photosynthetic machinery to obtain the maximum possible photosynthetic rate. Wethey and Porter (1976) suggest that the high photosynthetic rate of the "shade" corals at low light levels is due to their greater ability to absorb light in the 450 nm. light range. A large volume of phytoplankton research has investigated the differences between "sun" and "shade" adapted algae (algal cultures grown at high and low light intensities respectively) in their responses to changing light conditions (Steeman-Nielsen & Jorgensen, 1968; Steeman-Nielsen, 1973; Yentsch & Scagel, 1966; Ryther, 1956; Ryther & Menzel, 1959). These studies investigated the effects of changing light intensities on plant pigments, pigment ratios, enzyme systems, productivity, cell size, and growth rate, primarily on green algae, diatoms, and mixed phytoplankton populations. Although no studies of this type have investigated the light responses of dinoflagellates, it is assumed that the results obtained for diatoms apply to the Dinophyceae, which include zooxanthellae. The present study compares the effects of different light intensities on the zooxanthellae of "sun" and "shade" corals. Two Hawaiian species of hermatypic corals were selected for this purpose: Cyphastrea ocellina, a shallow reef species, and Leptoseris incrustans, a species limited to deep reef zones as well as shaded environments on shallow reefs.Item Trophic Relationships of Goatfishes (Family Mullidae) in the Northwestern Hawaiian Islands(University of Hawai'i, Honolulu, 1982-05-01) Sorden, Carol T.Item Aspects of Corallivory by Chaetodon unimaculatus in Kane'ohe Bay, Oahu(University of Hawai'i, Honolulu, 1983) Cox, Evelyn F.Interactions between a corallivore, Chaetodon unimaculatus, and the two dominant coral species in Kane'ohe Bay, Montipora verrucosa and Porites compressa, were investigated. Feeding selectivity was tested in laboratory and field observations, with the fish clearly selecting M. verrucosa: 39:1 bites in laboratory trials and 284:1 bites in field observations. Using an estimated bite size of 2.54 mg AFDW and two estimated feeding rates, 4.88 bites min-1 during the "dry" season (May to September) and 7.20 bites min-1 during the "wet" season (October to April), an average sized fish consumes approximately 4000 g of coral tissue each year, and the population of C. unimaculatus on Patch Reef #42 is removing approximately 10% of the standing crop of M. verrucosa each year. A series of experiments was designed to measure the effect of predation by these fish on growth and competition between the two corals. Caged colonies of M. verrucosa at Patch Reef #42 had a vertical growth rate of 9.71 x 10-3cm day-1, and M. verrucosa killed P. compressa tissue it came in contact with. In uncaged colonies, M. verrucosa grew at a rate of 3.92 x 10-3cm day-1, about 40% of the caged growth rate, and several colonies showed a reversal of aggressive dominance as predicted from previous studies, with P. compressa killing branches of M. verrucosa. On Patch Reefs #42 and #43 there is a significant increase in the percent M. verrucosa with increased distance from the edge of the reef, where the fish are normally found, and grazing pressure is greatest. Because of its selective feeding behavior in Kane'ohe Bay, C. unimaculatus appears to have a significant effect on the growth and distribution of its preferred coral species, M. verrucosa.Item Age, growth, reproduction and diet of Myripristis amaena at Johnston Atoll(1986) Dee, Anderson James; Zoological Sciences