Mid-Pacific Institute

About: Mid-Pacific Institute is a education organization based out in Honolulu, Hawaii, United States. It is known for research contribution in the topics: Gas chromatography & Phthalate. The organization has 18 authors who have published 22 publications receiving 455 citations. The organization is also known as: Kawaiahaʻo Seminary for Girls & Kawaiahaʻo Seminary.

Aspects of the spawning of labrid and scarid fishes (Pisces: Labroidei) at Enewetak Atoll, Marshall Islands with notes on other families

Abstract: Spawning of 32 species of Labridae and 13 species of Scaridae was seen at Enewetak Atoll, Marshall Islands. Most spawned on a reef bisecting the main ocean-lagoon passage which had strong tidal currents. Others spawned on lagoon reefs and in Halimeda beds. Polygynous haremic, lek-like and promiscuous mating systems were found which were species specific. Data on reproductive patterns, sexual dichromatism, sexual dimorphism, seasonality and spawning behavior were determined. Many spawned during the day in a time-phase dependent pattern from near sunrise to sunset. Scarid spawning began at slack high water or after when currents were starting to move out of the lagoon. Labrid spawning usually started about 30 min later with some continuing up to 2 h after high tide. With high tide before sunrise, scarid spawning began 30–50 min after sunrise as the current started flowing over the reef. With high tide near sunset, spawning occurred with an incoming current. Most labroids spawned on all phases of the moon. Acanthuridae (6 spp), Caesionidae (1 sp.) and Zanclidae (1 sp.) spawned after high tide at the same time as labroids. Pomacanthidae (5 spp.) spawned only shortly before sunset without reference to tidal currents. Fishes producing pelagic eggs at the lagoon-ocean channel spawned (1) at or slightly after high tide (44spp.), (2) in late afternoon without reference to tide (6 spp.) or (3) after slack low water (1 sp. ). Spawning style can vary within a single species in different environments. Despite the presence of many piscivores, no successful predation on spawning adults was seen. Predation on newly released eggs was uncommon. Labrichthys unilineata and Anampses twistii attempted to defend their eggs for a few sec after release. Attacks by piscivores on spawning adults on tropical reefs occur once per 100–1000 spawnings. Most are wary when preparing to spawn and prespawning behavior is easily interrupted. The risk from piscivores goes down and spawning ascent speed decreases with increasing size of spawners. Egg predation by zooplanktivores is less for pair spawners than group spawners possibly due to less conspicuous gamete clouds and times of spawning. Increasing height of egg release, speed and length of the spawning ascent, and trajectory alteration of ascending adults are believed to make it more difficult for zooplanktivores to locate eggs after release. For labrids, permanent full sexual dichromatism was found among haremic, lek-like and promiscuous mating systems. Species with temporary full dichromatism, permanent and temporary partial dichromatism and monochromatism were haremic. Smaller scarids were believed to have lek-like, and larger species haremic, mating systems. Smaller scarids had male looping behavior and post spawning displays, plus faster spawning ascents and different locations for egg release than larger ones. Eggs of 21 labrids were spherical or nearly spherical, ranging from 0.55–0.80 mm in diameter, and most had one oil globule. Among 7 is scarids, 6 had spindle-shaped eggs ranging from 1.25 ×0.50 mm 2.14× 0.48 mm while one had a nearly spherical egg. One scarid egg lacked an oil globule.

Courtship, spawning and inferred social organization of American angelfishes (Genera Pomacanthus, Holacanthus and Centropyge; pomacanthidae)

Abstract: Courtship, spawning and social organization are described for six species of American angelfishes, with notes provided on three additional species. In all species discussed, as well as all those in the western Pacific for which data are available, spawning occurs daily, throughout all or most of the lunar cycle, and involves pairing only. Both permanent sexual dichromatism and temporary dichromatism during courtship and spawning occur sporadically in the family and do not yet clearly correlate with any specific social regime. Sexual size dimorphism (males larger than females) is manifest by the genera Centropyge, Genicanthus, Holacanthus, and possibly Pomacanthus. Although protogynous hermaphroditism is documented for some angelfishes, it may be premature to conclude this for all, given the highly variable nature of their grouping. Social organizations vary from apparent monogamy (Pomacanthus paru) to male-dominated harems (Holacanthus ciliaris, H. tricolor, Centropyge argi) and to apparently promiscuous explosive breeding assemblages (Pomacanthus arcuatus) and a lek-like system (Holacanthus passer). Variation within some species may be as extreme. This flexibility suggests that selective pressures may not be unidirectional over a species' entire range. Consequently, manifested characteristics may vary geographically or may be some compromise determined by the degree of population panmyxia and the number and fecundity of individuals in each selective regime.

Economic feasibility of small-scale black-lipped pearl oyster (pinctada margaretifera) pearl farming in the central pacific

Abstract: This work provides an analysis of the economic feasibility of one of many small-scale aquaculture operations being considered, black pearl oyster farms, as one type of supplemental economic activity for outer island communities in the Central Pacific. Specifically, projections of financial performance of a small-scale 25,000 seeded pearl oyster farm using the Tahitian long-line method are being conducted. Estimates of initial capital investment and annual operating costs are being formulated, an annual cash flow and enterprise budget are being developed. Results show that initial capital investment is $202,076. Annual operating expenses are $293,726 during full operation. The largest costs contributing to annual operating expenses are seeding (46%), labor including farm owner's opportunity cost (24%), and depreciation (9%). The base model presented in this work suggests profitability over a 20-year horizon. Net returns over a 20-year farm horizon based on an 8% discount rate indicate a positive N...