25 results match your criteria: "University of Hawai'i Sea Grant College Program[Affiliation]"

Identifying processes that promote coral reef recovery and resilience is crucial as ocean warming becomes more frequent and severe. Sexual reproduction is essential for the replenishment of coral populations and maintenance of genetic diversity; however, the ability for corals to reproduce may be impaired by marine heatwaves that cause coral bleaching. In 2014 and 2015, the Hawaiian Islands experienced coral bleaching with differential bleaching susceptibility in the species Montipora capitata, a dominant reef-building coral in the region.

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With the expanding global population, interest has increased in the sustainable aquaculture development of indigenous fishes. In Hawai'i, the brassy chub, Kyphosus vaigiensis, has drawn interest as a candidate species for production. However, little is known about its resilience in aquaculture settings where fish are exposed to acute, husbandry-related stressors.

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Francisella orientalis DNA detected in feral tilapia populations in Hawai'i.

J Aquat Anim Health

December 2024

Animal and Veterinary Services Program, Biomedical Sciences, University of Hawai'i, Honolulu, Hawai'i, USA.

Article Synopsis
  • Francisella orientalis is a harmful bacteria that causes high death rates in warmwater fish like tilapia and has significantly impacted aquaculture worldwide, resulting in a moratorium on tilapia exports from Oahu since the mid-1990s due to repeated outbreaks.
  • A study was conducted to evaluate the presence of this bacteria in feral tilapia from various Hawaiian Islands using molecular and histological screening methods.
  • The results showed infection signs in fish from all five islands, but F. orientalis was only confirmed in Oahu, Maui, and Kauai, indicating its widespread prevalence among feral tilapia populations.
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Abandoned, lost, or otherwise discarded fishing gear causes harm to marine species and ecosystems. To mitigate the destruction wrought by this ocean plastic debris, various cleanup programs have been established, though to our knowledge the benefits of such efforts to marine species and ecosystems have not yet been empirically demonstrated. We examined more than 40 years of Hawaiian monk seal marine debris entanglement records before and after large-scale marine debris removal efforts were initiated in the Northwestern Hawaiian Islands, demonstrating a substantial reduction in entanglement rates where debris removal effort was most concentrated.

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Monitoring coral cover can describe the ecology of reef degradation, but rarely can it reveal the proximal mechanisms of change, or achieve its full potential in informing conservation actions. Describing temporal variation in Symbiodiniaceae within corals can help address these limitations, but this is rarely a research priority. Here, we augmented an ecological time series of the coral reefs of St.

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Pacific chub, Kyphosus sandwicensis, are typically gray but some individuals display a golden color morph. We estimated that the frequency of occurrence of the golden morphs increased significantly from 2007 (1.9%) and 2012 (2.

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Increasingly frequent marine heatwaves are devastating coral reefs. Corals that survive these extreme events must rapidly recover if they are to withstand subsequent events, and long-term survival in the face of rising ocean temperatures may hinge on recovery capacity and acclimatory gains in heat tolerance over an individual's lifespan. To better understand coral recovery trajectories in the face of successive marine heatwaves, we monitored the responses of bleaching-susceptible and bleaching-resistant individuals of two dominant coral species in Hawai'i, and , over a decade that included three marine heatwaves.

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Background: Plastics have conveyed great benefits to humanity and made possible some of the most significant advances of modern civilization in fields as diverse as medicine, electronics, aerospace, construction, food packaging, and sports. It is now clear, however, that plastics are also responsible for significant harms to human health, the economy, and the earth's environment. These harms occur at every stage of the plastic life cycle, from extraction of the coal, oil, and gas that are its main feedstocks through to ultimate disposal into the environment.

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The Republic of the Marshall Islands (RMI) has been affected by marine pollution from militarization and urbanization. To address concerns raised by the Marshall Islands Marine Resources Authority, this study examined concentrations of dissolved contaminants in reef and pelagic fishes in the RMI and assessed potential associated risks. Metals, organochlorine pesticides, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were examined in reef and pelagic fishes from six atolls: Kwajalein, Majuro, Jaluit, Utirik, Rongelap, and Wotje.

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The growth of intermittent renewable energy and climate change makes it increasingly difficult to manage electricity demand variability. Centralized storage can help but is costly. An alternative is to shift demand.

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Identifying relatively intact areas within ecosystems and determining the conditions favoring their existence is necessary for effective management in the context of widespread environmental degradation. In this study, we used 3766 surveys of randomly selected sites in the United States and U.S.

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Experimental Approaches for Characterizing the Endocrine-Disrupting Effects of Environmental Chemicals in Fish.

Front Endocrinol (Lausanne)

May 2021

Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States.

Increasing industrial and agricultural activities have led to a disturbing increase of pollutant discharges into the environment. Most of these pollutants can induce short-term, sustained or delayed impacts on developmental, physiological, and behavioral processes that are often regulated by the endocrine system in vertebrates, including fish, thus they are termed endocrine-disrupting chemicals (EDCs). Physiological impacts resulting from the exposure of these vertebrates to EDCs include abnormalities in growth and reproductive development, as many of the prevalent chemicals are capable of binding the receptors to sex steroid hormones.

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The sensitivity of prolactin (Prl) cells of the Mozambique tilapia (Oreochromis mossambicus) pituitary to variations in extracellular osmolality enables investigations into how osmoreception underlies patterns of hormone secretion. Through the actions of their main secretory products, Prl cells play a key role in supporting hydromineral balance of fishes by controlling the major osmoregulatory organs (ie, gill, intestine and kidney). The release of Prl from isolated cells of the rostral pars distalis (RPD) occurs in direct response to physiologically relevant reductions in extracellular osmolality.

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Tilapias comprise the second most aquacultured finfish group in the world. Such popularity stems in part from their tolerance to a wide range of environmental conditions and their sexually dimorphic nature, where males grow larger than females. As in other vertebrates, growth in tilapia is regulated by the growth hormone/ insulin like growth factor (GH/IGF) system.

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It is widely recognized that endocrine disrupting chemicals (EDCs) released into the environment through anthropogenic activities can have short-term impacts on physiological and behavioral processes and/or sustained or delayed long-term developmental effects on aquatic organisms. While numerous studies have characterized the effects of EDCs on temperate fishes, less is known on the effects of EDCs on the growth and reproductive physiology of tropical species. To determine the long-term effects of early-life exposure to common estrogenic chemicals, we exposed Mozambique tilapia (Oreochromis mossambicus) yolk-sac fry to 17β-estradiol (E2) and nonylphenol (NP) and subsequently characterized the expression of genes involved in growth and reproduction in adults.

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Euryhaline Mozambique tilapia (Oreochromis mossambicus) are native to estuaries where they encounter tidal fluctuations in environmental salinity. These fluctuations can be dramatic, subjecting individuals to salinities characteristic of fresh water (FW < 0.5‰) and seawater (SW 35‰) within a single tidal cycle.

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A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

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Evaluating exposure of northern fur seals, Callorhinus ursinus, to microplastic pollution through fecal analysis.

Mar Pollut Bull

January 2019

University of Hawai'i Sea Grant College Program, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, 2525 Correa Road, Hawai'i Institute of Geophysics 238, Honolulu, HI 96822, USA; University of Hawai'i Water Resources Research Center, University of Hawai'i at Mānoa, 2540 Dole St., Holmes Hall 283, Honolulu, HI 96822, USA.

Environmental microplastics are widely documented in marine life and bioaccumulation may present risks to marine predators. Investigations of microplastics in marine mammals are increasing, though none have examined animals routinely consumed by humans. Here, we investigate microplastic exposure in the northern fur seal (Callorhinus ursinus), a species consumed by humans, using fecal material.

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The effects of transfer from steady-state to tidally-changing salinities on plasma and branchial osmoregulatory variables in adult Mozambique tilapia.

Comp Biochem Physiol A Mol Integr Physiol

January 2019

Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI 96744, USA; Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA. Electronic address:

The Mozambique tilapia, Oreochromis mossambicus, is a teleost fish native to estuarine waters that vary in salinity between fresh water (FW) and seawater (SW). The neuroendocrine system plays a key role in salinity acclimation by directing ion uptake and extrusion in osmoregulatory tissues such as gill. While most studies with O.

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Planning community resilience to sea level rise (SLR) requires information about where, when, and how SLR hazards will impact the coastal zone. We augment passive flood mapping (the so-called "bathtub" approach) by simulating physical processes posing recurrent threats to coastal infrastructure, communities, and ecosystems in Hawai'i (including tidally-forced direct marine and groundwater flooding, seasonal wave inundation, and chronic coastal erosion). We find that the "bathtub" approach, alone, ignores 35-54 percent of the total land area exposed to one or more of these hazards, depending on location and SLR scenario.

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Hawai'i Coral Disease database (HICORDIS): species-specific coral health data from across the Hawaiian archipelago.

Data Brief

September 2016

Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD 20740, USA; Marine Geophysical Laboratory, Physics Department, College of Science, Technology and Engineering, James Cook University, Townsville, QLD 4811, Australia; Global Science and Technology, Inc., Greenbelt, MD 20770, USA.

The Hawai'i Coral Disease database (HICORDIS) houses data on colony-level coral health condition observed across the Hawaiian archipelago, providing information to conduct future analyses on coral reef health in an era of changing environmental conditions. Colonies were identified to the lowest taxonomic classification possible (species or genera), measured and assessed for visual signs of health condition. Data were recorded for 286,071 coral colonies surveyed on 1819 transects at 660 sites between 2005 and 2015.

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Autocrine Positive Feedback Regulation of Prolactin Release From Tilapia Prolactin Cells and Its Modulation by Extracellular Osmolality.

Endocrinology

September 2016

Hawai'i Institute of Marine Biology (Y.Y., D.T.L., E.G.G., A.P.S.), University of Hawai'i at Mānoa, Kāne'ohe, Hawai'i 96744; School of Marine Biosciences (S.M.), Kitasato University, Minami-ku, Sagamihara, Kanagawa 252-0373, Japan; and University of Hawai'i Sea Grant College Program (D.T.L.) and Department of Human Nutrition, Food and Animal Sciences (A.P.S.), University of Hawai'i at Mānoa, Honolulu, Hawai'i 96822.

Prolactin (PRL) is a vertebrate hormone with diverse actions in osmoregulation, metabolism, reproduction, and in growth and development. Osmoregulation is fundamental to maintaining the functional structure of the macromolecules that conduct the business of life. In teleost fish, PRL plays a critical role in osmoregulation in fresh water.

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The growth hormone (GH)/insulin-like growth factor (IGF) axis plays a central role in the regulation of growth in teleosts and has been shown to be affected by acclimation salinity. This study was aimed at characterizing the effects of rearing tilapia, Oreochromis mossambicus, in a tidally-changing salinity on the GH/IGF axis and growth. Tilapia were raised in fresh water (FW), seawater (SW), or in a tidally-changing environment, in which salinity is switched between FW (TF) and SW (TS) every 6h, for 4months.

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This study investigated the effects of two rearing salinities, and acute salinity transfer, on the energetic costs of osmoregulation and the expression of metabolic and osmoregulatory genes in the gill of Mozambique tilapia. Using automated, intermittent-flow respirometry, measured standard metabolic rates (SMRs) of tilapia reared in seawater (SW, 130 mg O₂ kg⁻¹ h⁻¹) were greater than those reared in fresh water (FW, 103 mg O₂ kg⁻¹ h⁻¹), when normalized to a common mass of 0.05 kg and at 25±1°C.

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