Research Studies in R2R Watersheds & Topical Links
The Atlas of the Reefs of West Maui
Released March 2020: The Nature Conservancy released the “Atlas of the Reefs of West Maui,” a comprehensive report compiling 20 years of data detailing changes in the abundance and diversity of marine life in West Maui. The ‘first-of-its-kind’ atlas includes data collected by public and private organizations at 2,600 sites stretching from the “Pali” Tunnel on Honoapiʻilani Highway to Līpoa Point north of Honolua Bay.
Citation: Minton, D., Carr, R., Fielding, E., & Conklin, E. 2020. Atlas of the Reefs of West Maui. The Nature Conservancy Hawai‘i. Honolulu, HI 97817. 228 pp.
Maui-area coral reefs described in detail, including threats
Released July 1, 2019
A new USGS Open-File Report describes the coral reefs of Maui, Moloka‘i, Lānaʻi, and Kahoʻolawe in detail, including location, extent, coral cover, and connectivity.
The nine major coral reefs surrounding Maui and three nearby Hawaiian Islands (collectively Maui Nui) are critical to the local ecology, culture, and economy. Reef health has slowly declined over decades, and recent events such as the 2015 thermal bleaching have accelerated reef loss significantly, in some areas by an order of magnitude. The publication also describes threats to reef health, including overfishing, land-based pollution, and climate change. The report provides information that could inform Federal and State governments in their effort to establish a network of large-scale, connected Marine Protected Areas for effective management and protection of coral reefs in Hawai’i.
Citation: Field, M.E., Storlazzi, C.D., Gibbs, A.E., D’Antonio, N.L., and Cochran, S.A, 2019, The major coral reefs of Maui Nui, Hawai‘i—Distribution, physical characteristics, oceanographic controls, and environmental threats: U.S. Geological Survey Open-File Report 2019–1019, 71 p., https://doi.org/10.3133/ofr20191019.
Baseline Assessment for Coral Reef Community Structure and Demographics on West Maui
Released Spring 2017
Detailed assessment of coral condition in West Maui to provide baseline for understanding changes in coral health that may result from mitigation actions by R2R.
Citation: Baseline assessments for coral reef
community structure and demographics on west Maui. Data
Report. NOAA Fisheries Pacific
Science Center, PIFSC Special Publication, SP-17-001, 44p.
2018 Update: Kahekili Herbivore Fisheries Management Area
Coral Reef Studies
By: Joseph Murray, Nancy G. Prouty, Sara Peek & Adina Paytan
Excess nutrient loading to nearshore environments has been linked to declining water quality and ecosystem health. Macro-algal blooms, eutrophication, and reduction in coral cover have been observed in West Maui, Hawaii, and linked to nutrient inputs from coastal submarine groundwater seeps. Here, we present a forty-year record of nitrogen isotopes (δ15N) of intra-crystalline coral skeletal organic matter in three coral cores collected at this site and evaluate the record in terms of changes in nitrogen sources. Our results show a dramatic increase in coral δ15N values after 1995, corresponding with the implementation of biological nutrient removal at the nearby Lahaina Wastewater Reclamation Facility (LWRF). High δ15N values are known to be strongly indicative of denitrification and sewage effluent, corroborating a previously suggested link between local wastewater injection and degradation of the reef environment. This record demonstrates the power of coral skeletal δ15N as a tool for evaluating nutrient dynamics within coral reef environments.
USGS 2011 Fact Sheet: From Ridge to Reef—Linking Erosion and Changing Watersheds to Impacts on the Coral Reef Ecosystems of Hawai‘i and the Pacific Ocean
By Jonathan D. Stock, Susan A. Cochran, Michael E. Field, James D. Jacobi, and Gordon Tribble
Characterization of dead zones of Porites compressa along Kahekili Beach Park Coral reefs around Maui Island have experienced rapid and severe declines in coral cover over the past 10-15 years (Williams et al. 2008). A 2009- 2010 Maui Wide Study investigating colony scale dynamics showed that patterns and causes of coral decline are site specific. “Dead zones” or areas of nearly 100% mortality of the coral Porites compressa have been observed at Kahekili Beach Park Maui, one of the degraded sites from the previous study. The site has a history of macro-algal blooms (Smith et al. 2005) and input of nutrient rich water via injection wells located at the Lahaina Wastewater Treatment facility just North of the site (Dailer et al. 2010). The goal of this study was to map the distribution of areas of low, intermediate and high levels of degradation and to monitor colonies to determine whether mortality is ongoing and if so to identify potential causes of mortality. Information on processes causing declines in coral coverage will allow more effective management to prevent, slow or reverse declines.
For more information: Information Sheet, Final Report or Figures
Key Contact: Paul Jokiel, University of Hawaii
Recovery of an Isolated Coral Reef System Following Severe Disturbance published in April 2013 in Science by Gilmour et al. shows how the recovery of reefs to thermally-induced bleaching is affected by local stressors. This further reinforces the idea that reducing local stressors, which can be managed a federal, state, and local level, increases the resilience of reefs to global stressors (CO2 emissions) that we seem unable to control.
Stormwater Management in Pacific and Caribbean Islands: A Practitioner’s Guide to Implementing LID was completed in February 2014 for the NOAA Coral Reef Conservation Program, prepared by Horsley Witten Group, Inc. and Center for Watershed Protection, Inc. It is an excellent resource, complete with photos and diagrams detailing how to adopt these practices.
NOAA’s National Ocean Service (NOS) and its partners have mapped almost 3 million acres of reef including those around Maui. Great reef maps for Maui and beyond are available in an interactive format at their website.
The Maui Coastal Use Mapping Project, was conducted as a partnership of DAR, NOAA PIRO and NOAA PSC. The project has mapped significant human uses (including range and intensity) of the nearshore area to inform resource management. See maps of where people are fishing, jet skiing, surfing and many other uses in an interactive format.
Links to Partner Agencies & Organizations
NOAA Coral Reef Program: http://coralreef.noaa.gov/
DLNR Department of Aquatic Resources: http://www.hawaiicoralreefstrategy.com/
U.S. Army Corps of Engineers: http://www.poh.usace.army.mil/
Hawaii State Department of Health: http://health.hawaii.gov/
U.S. Environmental Protection Agency: http://www.epa.gov/
U.S. Geological Survey: http://www.usgs.gov/
U.S. Fish and Wildlife Service: http://www.fws.gov/
National Fish and Wildlife Foundation: http://www.nfwf.org/coralreef/Pages/home.aspx#.U8SnrrHCd8E
Hui O Ka Wai Oka: https://www.huiokawaiola.com/
West Maui Mountains Watershed Partnership: http://www.westmauiwatershed.org/
The Nature Conservancy: http://www.nature.org
The Coral Reef Alliance: http://www.coral.org/
County of Maui: http://www.co.maui.hi.us/
Maui Nui Marine Resource Council: http://www.mnmrc.org/
Rigorously Valuing the Role of U.S. Coral Reefs in Coastal Hazard Risk Reduction
Open-File Report 2019-1027
Prepared in cooperation with the University of California Santa Cruz and The Nature Conservancy
The degradation of coastal habitats, particularly coral reefs, raises risks by increasing the exposure of coastal communities to flooding hazards. The protective services of these natural defenses are not assessed in the same rigorous economic terms as artificial defenses, such as seawalls, and therefore often are not considered in decision making. Here we combine engineering, ecologic, geospatial, social, and economic tools to provide a rigorous valuation of the coastal protection benefits of all U.S. coral reefs in the States of Hawaiʻi and Florida, the territories of Guam, American Samoa, Puerto Rico, and Virgin Islands, and the Commonwealth of the Northern Mariana Islands. We follow risk-based valuation approaches to map flood zones at 10-square-meter resolution along all 3,100+ kilometers of U.S. reef-lined shorelines for different storm probabilities to account for the effect of coral reefs in reducing coastal flooding. We quantify the coastal flood risk reduction benefits provided by coral reefs across storm return intervals using the latest information from the U.S. Census Bureau, Federal Emergency Management Agency, and Bureau of Economic Analysis to identify their annual expected benefits, a measure of the annual protection provided by coral reefs.
Citation: Storlazzi, C.D., Reguero, B.G., Cole, A.D., Lowe, E., Shope, J.B., Gibbs, A.E., Nickel, B.A., McCall, R.T., van Dongeren, A.R., and Beck, M.W., 2019, Rigorously valuing the role of U.S. coral reefs in coastal hazard risk reduction: U.S. Geological Survey Open-File Report 2019–1027, 42 p., https://doi.org/10.3133/ofr20191027.
Released March 2019
The project team assessed the relative resilience of reef sites at two depths along areas of West and South-West Maui ("leeward Maui") in March of 2018. The surveys were conducted as a collaborative effort with DAR, The Nature Conservancy, and community organizations. This report presents findings from meeting these project objectives: 1) assess benthic cover comparisons among sites and depths, 2) complete resilience assessment including relative resilience and rankings for two depths, 3) conduct analyses that determine the primary drivers of differences in resilience between sites, and 4) develop a framework for using the resilience analysis outputs to identify and prioritize potential management actions to support the resilience of coral reefs in Maui. Two page summary available here.
Citation: Maynard J, Conklin E, Minton D, Williams GJ, Tracey D, Amimoto R, Carr R, Fielding E, Lynch H, Rose J, Sparks R, Sylva R, White D. (2019). Assessing the Resilience of Leeward Maui Reefs to Help Design a Resilient Managed Area Network. NOAA Coral Reef Conservation Program. NOAA Technical Memorandum CRCP 33, 40 pp.
Released July 2017
The Use of Passive Membrane Samplers to Assess Organic Contaminant Inputs at Five Coastal Sites in West Maui, Hawaii
The County of Maui works in many ways to protect storm water and receiving waters from pollutants that could negatively impact receiving water quality. The County’s goal is to work with community individuals, businesses, large landowners, and State and Federal agencies to foster joint responsibility and positive action to protect our precious surface water resources. https://www.mauicounty.gov/2129/Storm-Water-Management-Program
Guidance for Watershed Managers
The US Coral Reef Task Force Watershed Working Group Metrics Subcommittee has developed metrics guidance documents to assist with what parameters are important for watershed managers to collect to track progress. The priority Ecosystem Indicators include water quality and coral metrics, while the Programmatic Checklist focuses on the non-ecological factors that play into success, such as institutional support, a watershed management plan, local governmental support etc.
Reconnaissance Sediment Budget for Selected Watersheds of West Maui, Hawai‘i
Open-File Report 2015-1190
By:Jonathan D. Stock, Kim A. Falinski, and Tova Callender
ABSTRACT: Episodic runoff brings suspended sediment to the nearshore waters of West Maui, Hawaiʻi. Even small rainfalls create visible plumes over a few hours. We used mapping, field experiments, and analysis of recent (July 19–20, 2014) and historic rainfall to estimate sources of land-based pollution for two watersheds in West Maui: Honolua, and Honokōwai. Former agricultural fields and some unimproved roads are plausible sources for polluted runoff, but have saturated hydraulic conductivities greater than the 10–15 millimeters per hour rainfalls of July 2014. These fields and roads showed minor evidence for storm runoff, and could not have contributed substantially to July 2014 plume generation. Since 1978, rain at intensities capable of causing runoff from former agricultural fields sustained for 1–2 hours is also rare; such intensities have 2–5 year recurrence rates in the north, and greater than 25 year recurrence rates to the south near Lahaina. Streambanks now eroding into historic terraces of sands, silts, and clays are a more plausible source. Although past large storms contributed to sediment loading, annual plume generation is now caused by smaller rainfalls eroding these near-stream legacy deposits. Treatments of former agricultural fields, roads, and reserve forests are consequently not likely to measurably affect sediment pollution from smaller, more frequent storms. Increased runoff from the development of West Maui has the potential to exacerbate sediment plumes from such storms unless there is an effective strategy to reduce bank erosion. Uncertainties in the extent and erosion rate of historic terraces, however, limit our ability to plan mitigation.
Rain Catchment Resources
In 2004, CTAHR developed Guidelines on Rainwater Catchment Systems for Hawai‘i. An estimated 30,000 to 60,000 people in the state of Hawai‘i are dependent on a rainwater catchment system for their water needs. With proper design, maintenance, and water treatment, a rainwater catchment system can provide water that is relatively free of contamination, soft, clear, and odorless; this water can be used for drinking, bathing, washing, flushing,laundry, and gardening. Follow the link to read the 52 page guide and begin catching your own water!
Rain Garden Resources
Six minute PBS video documenting a movement in Seattle to install 12,000 rain gardens.
This community based non-profit on Oahu developed Hawaii's first rain garden manual (below) and has great rain garden examples and resources available on line.
Download the Hawaii Residential Rain Garden Manual here
The USGS Pacific Coastal & Marine Science Center has conducted considerable research in West Maui on topics such as coral larval dispersal, coastal circulation and sedimentation patterns, the impact of sediments and much more (see presentation below right). Check out the link dedicated to work on Maui. http://coralreefs.wr.usgs.gov/maui.html
Additional Resources from the USGS Pacific Coastal & Marine Science Center Team
Cochran, S.A., Gibbs, A.E., and White D.J., 2014, Benthic habitat map of the U.S. Coral Reef Task Force Watershed Partnership Initiative Kāʻanapali priority study area and the State of Hawaiʻi Kahekili Herbivore Fisheries Management Area, west-central Maui, Hawaiʻi: U.S. Geological Survey Open-File Report 2014-1129, 42 p.
Gibbs, A.E., Cochran, S.A., and Tierney, P.W., 2013, Seafloor video footage and still frame-grabs from U.S. Geological Survey cruises in Hawaiian nearshore waters: U.S. Geological Survey Data Series 735, 11 p.
Gibbs, A.E., Grossman, E.E., and Richmond, B.M., 2005, Summary and preliminary interpretations of USGS cruise A-2-02-HW; Underwater video surveys collected off of Oʻahu, Molokai, and Maui, Hawaii, June-July 2002: U.S. Geological Survey Open-File Report 2005–1244, 57 p.
and there are numerous other data associated with positions listed in tables in the following reports:
Storlazzi, C.D. and Presto, M.K., 2005. “Coastal Circulation and Sediment Dynamics along West Maui, Hawaii, PART IV: Measurements of waves, currents, temperature, salinity and turbidity in Honolua Bay, Northwest Maui: 2003-2004” USGS Open-File Report 2005-1068, 34 p. http://pubs.usgs.gov/of/2005/1068/
Storlazzi, C.D., Field, M.E., Ogston, A.S., Logan, J.B., Presto, M.K. and Gonzales, D.G., 2004. “Coastal Circulation and Sediment Dynamics along West Maui, Hawaii, PART III: Flow and particulate dynamics during the 2003 summer coral spawning season” USGS Open-File Report 2004-1287, 36 p. http://pubs.usgs.gov/of/2004/1287/
Hatcher, G.A., Reiss, T.E. and Storlazzi, C.D., 2004. “Application of GPS drifters to track Hawaiian coral spawning” USGS Open-File Report 2004-1309, 14 p. http://pubs.usgs.gov/of/2004/1309/
Storlazzi, C.D., Logan, J.B., McManus, M.A., and McLaughlin, B.E., 2003. “Coastal Circulation and Sediment Dynamics along West Maui, Hawaii, PART II: Hydrographic Survey Cruises A-3-03-HW and A-4-03-HW Report on the spatial structure of currents, temperature, salinity and turbidity along Western Maui” USGS Open-File Report 03-430, 50 p.
Storlazzi, C.D. and Jaffe, B.E., 2003. “Coastal Circulation and Sediment Dynamics along West Maui, Hawaii, PART I: Long-term measurements of currents, temperature, salinity and turbidity off Kahana, West Maui: 2001-2003” USGS Open-File Report 03-482, 28 p. http://pubs.usgs.gov/of/2003/of03-482/