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Graduate students in boat prepare to dive in the bay for science.

Fish Flow: Filling the gap between spawning and settlement

PI: Brian Bowen
This project aimed to track reef fish, using their genetic data, from where they spawned as larvae to where they settle on the reef, as a direct measure of population connectivity. Engaging student volunteers, the research team collected over 1500 samples of three target species across the Hawaiian islands. Using advanced genetic technology and computer-aided population connectivity texts, the team generated maps that illustrate that most adult reef fish in Kāneʻohe Bay originate from neighboring East Oʻahu reefs rather than from inside the bay, useful information for appropriate managers.
Lucie Knor in the lab

Coastal Ocean Hawaiʻi Acidification Monitoring Network (COHAMN) and carbonate mineral dissolution study

PI: Eric DeCarlo
This project is part of a long-term, ongoing effort to record carbon dioxide concentrations in multiple coral reef settings, producing the longest continuous CO2 record in the world from a coral reef environment, and has illustrated that time series data are critical to understanding and quantifying reef contributions to global carbon cycling. Results so far show that, currently, Hawaiian coastal waters largely release CO2 to the atmosphere, but with elevated carbon dioxide that is absorbed, models show that tropical reefs will be net dissolving by the mid-21st century.
Graduate students measure Auimanu Stream water quality

The role of surface and groundwater inputs in driving water quality in Kāneʻohe Bay, Oʻahu

PI: Henrietta Dulai
The goal of this project was to identify submarine groundwater discharge locations and quantify groundwater and its derived nutrient flow into Kāneʻohe Bay, particularly as it varies with wet and dry seasonal cycles. The researchers found that most freshwater in nearby coral reefs derives from streams during the wet season, but during the dry season, input from groundwater increases 150%. These results have led to maps with quantification of groundwater discharge, and measurements of nutrient fluxes have identified several watershed hotspots of wastewater contamination.
Diver planting coral nubs

Mitigating climate change impacts: What drives thermal resiliency in Hawaiʻi’s coral reefs?

PI: Ruth Gates
This study aimed to understand the biology and physiology of corals, their symbiotic algae, and microbial communities that underpin different responses to bleaching events, why some coral colonies survive bleaching and others do not. Thermal resilience was tested in four coral species important to Hawaiʻi, examining the role of morphology, tissue thickness, and behavior of bacterial communities in bleaching recovery. Results showed that after two weeks at high heat, rice coral (Montipora capitate) was most resistant to bleaching, although all four species returned to normal after four weeks of recovery time. Most susceptible to bleaching was the lace coral (Pocillopora acuta), which has the thinnest tissues.
Graduate students set up equipment in stream

Collaborative investigation of hydraulic and geochemical connectivity between wastewater and land-use and the oceanic waters of Kāneʻohe Bay, Oʻahu

PI: Craig Glenn
This project examined the environmental and health risks of wastewater leakage from on-site sewage disposal systems, by assessing the hydraulic and geochemical connectivity between wastewaters and ocean waters of Kāneʻohe Bay using field studies and pioneering thermal infrared imaging mounted on unmanned aerial vehicles (UAVs). The remote sensing enabled the team to produce high-resolution maps of groundwater and wastewater leakage from local septic systems into waters of the Kahaluʻu watershed and Kānaʻohe Bay. A local-scale model was developed from sixteen months of data that will help inform remediation strategies to address wastewater leakage problems in the area.
Student collecting water sample from beach shallows.

Rapid Response: Application of a qPCR-based test for Enterococci as a rapid beach management tool in Hawaiʻi

PI: Marek Kirs
The goal of this project was to design a rapid, simple, molecular-based water quality test that authorities can easily apply on Hawaiian beaches to increase hazard resilience of coastal communities. Standard coastal water quality testing techniques require 24-48 hours of culturing Enterococci bacteria, which often gives falsely high readings in Hawaiʻi from environmental sources. This newly developed method uses a specifically human-sewage-borne pathogen, Bacteroides, detected by rapid molecular tests, and is proving to give efficient and accurate detection of contamination to provide more timely notice and better protect public health.
Arlan Brucal working on computers with models

Do seawalls lower property values?

PI: John Lynham
This work examined the economic consequences of a strategy commonly used in years past of building sea walls to protect property threatened by increased coastal erosion. Based on a technique previously used successfully by the authors in San Diego, CA, the researchers examined property sales on Oʻahu for the last 30 years and combined this with locations of seawalls built over those years. They found that while properties with coastal armoring maintain their value, there is evidence that neighboring properties show a decrease in value with time.
Contamination warning sign on Kailua Beach

Source tracking coastal groundwater and runoff contamination with microbial genomics and dissolved organic fluorometry

PI: Craig Nelson
This project focused on using new techniques of microbial genomics and fluorescent characterization of organic matter to track sources of groundwater contamination in several important Hawaiian watersheds, in order to provide tools to protect streams, groundwater, and coastal ecosystems. The high density of cesspools in Hawaiʻi is a potentially significant source of contamination to streams and coral reefs, but it is currently prohibitive to identify contamination sources. For this project, hundreds of water samples from Oʻahu, Maui, and Hawaiʻi have been collected and are being characterized to develop microbial source tracking and better testing techniques.
Green plume of dye drifts upward from red sponge in fishtanks

The role of sponges in nitrogen cycling in Kāneʻohe Bay, Oʻahu

PI: Brian Popp
This study focused on quantifying respiration, pumping rates, and chemical reactions of an invasive sponge, Mycale grandis, to understand the species’ impacts on nitrogen cycling in the coastal environment of Kāne‘ohe Bay, whether adding or subtracting usable nitrogen from the system. Researchers found that the M. grandis sponge can pump 83 times its own volume of water per day, giving its associated microbial communities abundant opportunity to perform nitrification, converting ammonia to forms of nitrogen oxides unusable to algae. The rapid nitrogen transformations with the high pumping rates of these sponges means this invasive species may play a significant role in nitrogen concentrations in the bay.
Graphic showing average temperature and water consumption on O'ahu.

Predicting Hawaiʻi water demand under climate change

PI: Michael Roberts
This project studied how climate change may affect future water demand on Oʻahu, focusing on variations in temperature, precipitation, and prevailing climatic conditions. Results imply that microclimates play an important role in demand, with the hot and dry area households using typically 100 gallons more per day than those in cooler, wetter aras. Using water billing data cross-referenced with fine-scale weather data, a model was developed that estimates the growth of Oʻahu aquifer yields needed to satisfy possible shifts in demand (up to 50% increase) under different climate scenarios, or alternatively, the price increases necessary to limit consumption levels.
A tiny juvenile tilapia perches on the lip of its mother.

The use of a euryhaline Tilapia to assess the endocrine disrupting effects of anthropogenic chemicals on growth and osmoregulation of a tropical teleost species inhabiting coastal waters and wetlands in Hawaiʻi and the tropics

PI: Andre Seale
This work sought to understand the integrated physiological and developmental effects of endocrine-disrupting agricultural chemicals on the tropical euryhaline tilapia, Oreochromis mossambicus. Mozambique tilapia are widely used for aquaculture production so this research may better inform those interested in the effects of these waterborne chemicals on the growth and health of these fish. It will also provide critical information towards proper management of pesticide use and water resources to mitigate the effects of these agricultural chemicals on aquatic wildlife in general.
Students examine tidal pools

Longitudinal assessment: Our Project in Hawaiʻi’s Intertidal (OPIHI)

PI: Kanesa Seraphin
This project revisited the Hawaiian intertidal zone, last studied over a decade ago, to document, monitor, and assess changes in species compositions due to factors like climate change, coastal development, and the spread of invasive species. The project trained and mentored undergraduate students as interns, for college credit, gaining important, required hands-on research experience. By engaging these students as well as community members in this place-based research, 48 comprehensive surveys were completed across the state, with preliminary results suggesting the spread of invasive algae and changes to water quality.
Aerial view of wastewater treatment plant.

Assessing the vulnerability of coastal wastewater infrastructure to climate change

PI: Daniele Spirandelli
This research aimed, with community and agency stakeholders, to identify and map critical factors contributing to wastewater infrastructure vulnerability to a changing climate, particularly sea-level rise and extreme precipitation, and to develop a process that builds adaptive capacity into the system. Results showed groundwater inundation as a significant threat to sewer pipes, and a policy gap analysis identified discontinuities in key components of Hawaiʻi’s current onsite management program between land-use planning efforts and state siting regulations.
Photo of Heeai Fishpond wall.

Integration of next-generation sequencing into traditional Hawaiian practices to improve management and restoration of fishponds

PI: Robert Toonen
With Hawaiian fishponds as models of sustainable aquatic resource management, this study uses two important crab species, Portunus sanguinolentus hawaiiensis and Scylla serrata, to explore whether fishponds are self-seeding, importing, or exporting species, and whether traditional harvest practices continue to be viable. Early results show a broad diversity of crab sizes, with a possibility of tagging and tracking crabs outside the fishpond, as well as within.
Corals spread across the dark sea floor.

Predicting and mapping Hawaiian mesophotic coral ecosystems for sustainable coastal development

PI: Robert Toonen
This study sought to address our fundamental lack of knowledge regarding vulnerable low-light, mesophotic coral ecosystems (at depths of 30-180 m) in order to better manage impacts from invasive species, coastal development, and exploration. By using statistical modeling, combined with machine learning, researchers created predictive maps to illustrate the distribution of mesophotic reefs and invasive algae across the main Hawaiian Islands. They found that all islands had some stretches of coastline identified as highly susceptible to invasion of the green alga Avrainvillea amadelpha, in both shallow and mesophotic depths.
Colorful fish swim around coral of various varieties

Harnessing environmental DNA for healthy reefs

PI: Brian Bowen
This study monitors the health of coral reefs by using environmental DNA collected from waters around the reefs to identify which species are present, including cryptic and hidden ones, and to track the overall biodiversity on reefs in response to environmental stressors.
A student perched on the edge of a boat grins for the camera as she holds sampling equipment.

Coral reef CO2 variations at the Coastal Ocean Hawaiʻi Acidification Network (COHAMN): Impact of basin scale oceanographic forcing

PI: Eric DeCarlo
This project continues the decade-old MAPCO2 buoy program at four coral reef sites around Oʻahu, measuring CO2 in the atmosphere and dissolved in seawater as well as other parameters relevant to CO2 biogeochemistry, as part of an ongoing global CO2 monitoring program.
Construction cranes tower over the buildings and houses of urban Oʻahu.

Land-based pollutants in herbivorous reef fishes on Hawaiian reefs

PI: Megan Donahue
This work compares concentrations of metal pollutants in reef fish muscle tissue collected at several sites suffering, to different degrees, from contamination due to urban runoff into watersheds and coastal waters. The researchers aim to identify species and locations most impacted and aid communities to minimize the effects of land-based pollutants on coral reefs.
A cement-sided channel of water runs through fields, with Waianae Mountains in the distance.

Economic activity, technological progress, and water resource utilization on Oʻahu

PI: Peter Fuleky
These researchers are developing summary measures of economic conditions in various industries (especially tourism, health care, food, and agriculture) to establish the levels of dependency on the state’s limited water resources and likely future demand under various scenarios of economic, technological, and population change.
Researchers on a beach release a drone into the air

Collaborative investigation of hydraulic and geochemical connectivity between wastewaters and other land-uses and the ocean waters of Waialua Bay, Oʻahu

PI: Craig Glenn
This project assesses the hydraulic and geochemical connectivity between on-site sewage disposal system wastewaters and the oceanic waters around the greater Waialua Bay area, Oʻahu, to help develop a more complete understanding of the environmental and health risks of wastewater leakage.
Scenic beach pictures showing extreme erosion at the very base of the Royal Kahana hotel.

West Maui wave run-up forecasts

PI: Douglas Luther
This project plans to develop short-term forecast models of wave-driven inundation “run-up” events for West Maui, to help managers, emergency management personnel, and the public cope with the increasing hazards of flooding events, and associated erosion, driven by wave activity superimposed on rising sea levels.
Pots of plants watered by automated Intelligent Plant-growing System

Impacts of climate changes on a native and an invasive Hawaiian plant using a newly developed Intelligent Plant growing System (IPS)

PI: Camilo Mora
This study uses a previously-developed, affordable Intelligent Plant growing System (IPS) that employs automation technology to control climatic conditions precisely. For this project, the system will be applied to assess the viability of plants under multiple co-occurring climatic changes and prepare managers for future decision-making to cope with agricultural and vegetation issues as the climate shifts.
A view across the water towards the Honolulu skyline.

Enabling real-time predictive modeling of microbial pathogen risk along the Honolulu shoreline

PI: Craig Nelson
This project generates a real-time predictive model of microbial pathogen risk for the south shore of Oʻahu, an area with some of the highest instances of recreational waterborne disease in the U.S. Ideally, the model will be easily applied and interpreted by health agencies for the benefit of the general public.
Student and teacher volunteers aid in cataloging life in the intertidal zone.

Our Project In Hawaiʻi’s Intertidal (OPIHI): Examining change over time

PI: Joanna Philippoff
OPIHI, Our Project in Hawaiʻi’s Intertidal, continues a long-term effort to expand knowledge of the vulnerable intertidal zone across Hawaiʻi, engaging students and communities in collecting meaningful data used to characterize whether and how intertidal organisms’ abundance and diversity is changing over time.
Growth optimization and survival of the bleaching-resistant coral genus Pavona for reef restoration in Hawaiʻi

Growth optimization and survival of the bleaching-resistant coral genus Pavona for reef restoration in Hawaiʻi

PI: Peter Marko
These researchers are aiding in bleached coral-reef restoration efforts by experimentally determining optimal nursery growth conditions for the stress-tolerant coral genus Pavona and evaluating the role of colony size and morphology variation on out-planted coral survival at restoration sites.
Computer colored blue overlying aerial photo of Kauai'i coastal community, illustrating excessive flooding expected from sea level rise

Integrating climate science with local knowledge through community vulnerability assessment on Kauaʻi

PI: Daniele Spirandelli
This study examines the opportunities and challenges of integrating coastal resilience into local community plans, using the County of Kauaʻi’s efforts as a case study. Researchers will combine broader climate science risk information with local knowledge to support statewide goals to prepare counties for future climate hazards.
A robotic arm holds a label saying HURL7 in front of a dark blue coral reef area

Investigating the origin and impact of sedimentation on the health of Hawaiian mesophotic reefs for sustainable coastal development

PI: Robert Toonen
This project continues collecting data from mesophotic zones (30-180 m depths) around Oʻahu and West Maui to update models and develop predictive maps of coral and invasive algae distribution, in order to help managers and policymakers choose best strategies for coastal development and runoff control to protect these vulnerable low-light ecosystems.
Linear sets of depth values running off the beach show profile measurements.

A next generation beach observing system for Hawaiʻi

PI: Charles Fletcher
With sea-level rise impacting Hawaiian coasts, this project aims to develop a next-generation program for monitoring short and long-term changes in Hawaiian shorelines, employing recent technologic advances to enhance the efficiency and data quality of beach surveys, and ultimately, to improve accuracy and coverage of beach monitoring databases.
Scenic picture of Hawaiian fishpond.

Hehihehi management for microbial-mediated sediment removal in fishponds

PI: Kiana Frank
This study employs the modern tools of microbiology to examine the efficacy of a traditional management tool applied to today’s fishpond restoration efforts. The researcher is examining whether microbes may decompose pond-clogging sediment faster if aided by hehihehi, the traditional practice of stomping and mixing of the fishpond sediment.
Live nubby coral is pink, with a band at its top that looks mostly whitish, with a connected section above that in dead brown.

Disease outbreak investigation on the reefs of Kauaʻi

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Greta Aeby Co-INVESTIGATORS: Sean Callahan Graduate Trainee: Christina Runyon Outbreaks of coral disease can kill large numbers of corals and are occurring more frequently on the reefs of Hawaiʻi. In 2012, an Eyes of the Reef
A mother humpback whale with her calf swim together

The effects of anthropogenic noise on communications between humpback whale mother-calf pairs

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Whitlow Au Co-INVESTIGATORS: Adam Pack Graduate Trainee: Jessica Chen Humpback whales in Hawaiʻi are a major attraction to whale watching tours. Humpback whales have recently been reassessed by the National Oceanic and Atmospheric Administration, which administers
A large outcrop of coral shows nearly half discolored a distinct white

Maintaining healthy coastal ecosystems: Understanding disease risk of Hawaiʻi’s coral reefs and sources of coral pathogens

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Sean Callahan Co-INVESTIGATORS: Greta Aeby Graduate Trainee: Amanda Shore Disease is an emerging problem to coral reef ecosystems worldwide. Yet, the basic mechanisms of disease in corals are poorly understood. For infectious diseases, vectors allow the
A large yellow buoy floats in Hawaiian waters with a view of Diamond Head in the background.

Ocean Acidification Monitoring Network: Oʻahu, Hawaiʻi

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Eric DeCarlo Co-INVESTIGATORS: Michael Guidry, Fred Mackenzie Graduate Trainee: Gerarda Terlouw The Ocean Acidification Monitoring Network program has examined the biogeochemistry of the water column and waters within the carbonate sediments in Kāneʻohe Bay and on
A rippled, shallow stretch of blue-green water sparkles in the sun.

Groundwater-derived nutrient uptake in coastal ecosystems as driver of reef accretion-erosion balance

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Megan Donahue Co-INVESTIGATORS: Henrietta Dulai, Florence Thomas Graduate Trainee: Catherine Lubarsky Coastal coral reefs are subject to freshwater impacts from many sources, including runoff from rivers and streams and discharge of groundwater into the coastal ocean.
A peninsula with houses and palm trees sticks out into the waves of a blue ocean

Groundwater-derived nutrient uptake in coastal ecosystems as driver of reef accretion-erosion balance

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Henrietta Dulai Co-INVESTIGATORS: Peter Fuleky Graduate Trainee: Christina Richardson The last century of human activity has dramatically affected coral reefs. Global changes, due to increased atmospheric carbon dioxide, and local changes, like coastal development and overfishing,
A car drives through foot-deep water between industrial buildings.

Groundwater inundation: Doubling community damage from sea level rise

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Chip Fletcher Graduate Trainee: Shellie Habel Many of the Nation’s largest cities face risk of sea level rise induced flooding owing to their limited elevations and proximities to the coastline. Climate scientists generally agree that
Picture looks along the coastline, where ocean waves come right up to palm trees, hotels, and condominiums.

Quantifying transport and land-use impacts of groundwater and nutrient loadings to the coastal zones of Maui

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Craig Glenn Co-INVESTIGATORS: Henrietta Dulai, Aly El-Kadi, Jaque Kelly, Paul Lucey Graduate Trainee: Joseph Kennedy Increased nutrient addition to the coastal zone via submarine groundwater discharge (SGD) has been suspected as the primary cause of the
Oysters displayed in a black wire cage

Evaluation of the economic feasibility and marketing potential of the new Hawaiʻi oyster industry

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Ping Sun Leung Co-INVESTIGATORS: Maria Haws, Robert Howerton, Quentin Fong Graduate Trainee: Jessie Qay Chen Oysters displayed in a black wire cage There is little information on the costs of designing and operating small-scale farms and associated industry activities (i.e. depuration) in
Forecasting climate change impacts on coastal ecosystem services in Hawaiʻi through integration of ecological and social participatory models

Forecasting climate change impacts on coastal ecosystem services in Hawaiʻi through integration of ecological and social participatory models

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Christopher Lepczyk Co-INVESTIGATORS: Steven Gray Graduate Trainee: Hla Htun Both climate and land use/cover changes are expected to have significant impacts on freshwater ecosystem services and human well-being. Understanding and modeling these impacts in a manner
Healthy taro plants in a lo'ii

Global and regional vulnerability to 21st century climate shifts in current areas of plant growth

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Camilo Mora Graduate Trainee: Alessandra Shea Terrestrial plant production is a fundamental component of the carbon cycle on Earth, which delivers numerous ecological, economic, social and aesthetic goods and services to humanity. A growing body
Groundwater-derived nutrient uptake in coastal ecosystems as driver of reef accretion-erosion balance

Groundwater-derived nutrient uptake in coastal ecosystems as driver of reef accretion-erosion balance

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Florence Thomas Co-INVESTIGATORS: Henrietta Dulai, Megan Donahue Graduate Trainee: Florybeth LaValle For coral reefs to persist grown of the reef must exceed the erosion of the reef due to chemical and biological erosion. Inputs of nutrients
Humankind's biogeochemical experiment: Ocean acidification and "coral reef" dissolution

Humankind’s biogeochemical experiment: Ocean acidification and “coral reef” dissolution

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Michael Guidry Co-INVESTIGATORS: Eric DeCarlo, Fred Mackenzie Graduate Trainee: Robert Thompson Ocean acidification (the process by which the surface waters of the ocean are becoming more acidic due to absorbing atmospheric carbon dioxide generated, in part,
A single tilapia is highlighted in front of a school of dappled tilapia

The development of acclimation salinity-based rearing strategies to maximize growth in Mozambique Tilapia, Oreochromis mossambicus

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Andre Seale Co-INVESTIGATORS: Kevin Weng Graduate Trainee: Keano Pavlosky With the increased pressure on global fish populations, demand for sustainable aquaculture has risen dramatically. Developing and maintaining a safe and sustainable seafood supply, therefore is of
Assorted tropical fish swim around a tall coral outcrop

Defining ecosystem-based management boundaries using genetics and fisheries data

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Robert Toonen Graduate Trainee: Johanna Wren In this study, we compile and assess existing population data for marine species throughout the Hawaiian archipelago and test whether these data reveal distinct populations among sites within the
A net with solitary coral growth hangs in murky bay waters

Coral adaptation and acclimitization to global change: Resilience to hotter, more acidic oceans

 Research Projects 2014-2016
PRINCIPAL INVESTIGATOR: Robert Toonen Graduate Trainee: Christopher Jury We showed that three of the most common species of Hawaiian reef-building corals (Rice coral, Montipora capitata; Lace coral, Pocillopora damicornis; and Finger coral, Porites compressa) show significant differences

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