1. Document coral species coverage and species richness in the daytime at Honolua Bay, Kahekili Park, Puamana and Olowalu and compare data with earlier baseline work to detect changes at each site over time.
2. Examine relative density and species richness of fish in the daytime at Honolua Bay, Kahekili Park, Puamana and Olowalu and compare data with earlier baseline work to detect changes at each site over time.
3. Analyze water quality characteristics (temperature, visibility and salinity) at each dive site and examine temporal trends for these values.
4. Measure physical parameters (sediment influence and water motion) at each of our dive sites to quantify the impact from these structuring factors.
5. Survey additional sites to characterize reef communities with respect along an environmental gradient reflecting degree of wave exposure.
6. Investigate changes in the trophic composition of the fish communities at Honolua Bay, Kahekili Park, Puamana and Olowalu.
Resource Description: NODC Accession Number 9900242
Study Areas: The primary work area was within the waters bounded by the islands of Maui, Kahoolawe and Lanai in the state of Hawaii. The majority of the data was collected while SCUBA diving at relatively shallow depths (less than 20m). Specific sites were selected on the basis of prior surveys, levels of human use, accessibility and dive conditions. Long term (since 1991) monitoring sites included Honolua Bay, Puamana, and Olowalu. Water depths ranged from 3.2 meters at Honolua Bay during a low tide to 13.4 meters at Puamana. Varying degrees of exposure to physical parameters, terrestrial run-off and public use influences these areas.
SITE SITE Latitude Longitude No. NAME (N) (W) ----- ------------------- -------- --------- 1.00, Honolua South 21 00.45 156 38.85 * 2.00, Honolua North 21 00.90 156 38.35 3.00, Maui Prince 20 38.90 156 27.00 4.00, Puamana Offshore 20 51.00 156 39.50 * 5.00, Puamana Nearshore 20 51.00 156 39.30 6.00, Olowalu Offshore 20 48.10 156 36.80 * 7.00, Olowalu Nearshore 20 48.30 156 36.45 8.00, Artificial reef 20 51.50 156 40.20 9.00, Kahekili Site 1 20 56.10 156 42.00 10.00, Kahekili Site 2 20 56.30 156 42.00 * 11.00, Kahekili Site 3 20 56.50 156 42.00 * 12.00, Lahaina Shores 20 51.85 156 40.45 * 13.00, Honokowai 20 57.00 156 42.65 * 14.00, Puamana 25.0 20 51.25 156 39.30 * 15.00, Airport - UH Algae 20 54.75 156 25.70 * 16.00, Maalaea - UH Algae 20 47.30 156 30.45 * 17.00, Club Lanai 20 50.38 156 48.88 18.00, Fish Rock - Lanai 20 44.40 156 53.36 19.00, Napili - UH Algae 20 59.85 156 40.40 20.00, Embassy - UH Algae 20 58.10 156 41.90 21.00, Five Graves 20 40.20 156 26.90 22.00, Drainpipe 20 46.90 156 33.00 23.00, Windmills 21 01.30 156 37.30 24.00, La Perouse 20 36.00 156 25.50 25.00, Puu Olai 20 38.70 156 27.10 26.00, Maalaea Harbor - In 20 47.20 156 30.45 * 27.00, Maalaea Harbor - Out 20 47.30 156 30.45 28.00, Coral Gardens 20 47.50 156 34.10 29.00, Molokini - East 20 38.00 156 29.30 * 30.00, Molokini - Center 20 38.00 156 29.45 31.00, Molokini - West 20 38.00 156 29.60 *
*Location estimated from navigational chart by NODC personnel. All others were determined by Eric Brown using navigational charts.
SAMPLING PERIODS: 926 surveys between 25 June 1989 and 10 November 1998 through all seasons during daylight hours. Largest gap in surveys is between 19 July 1989 and 06 October 1991
METHODOLOGY
All data were collected with assistance of SCUBA using several methods for analyzing the coral reef habitat. Coral diversity and percent coverage were examined using the quadrat method described by Reed (1980). Modifications of the quadrat method have been used quite extensively in the literature as a method to detect gross changes in the reef flat community structure (Dahl, 1981; Coyer and Whitman, 1990).
The quadrat grid was 1m2 in area and consisted of 1 inch PVC tubing fitted with nylon line spaced 10 centimeters apart to form a grid with 81 intersections. Each quadrat was placed on the substrate and spaced 10 meters apart on a single 50 meter transect line from a underwater reference mark (Prior to 1994 we used a 100 meter transect line). The 50 meter transect line, consisted of 1/4-inch diameter nylon rope that was marked at 1-meter intervals with weights every 10 meters. Placement of the quadrats was predetermined before each dive so that at least 20% of each transect was mapped during the season. Different species of coral as well as the substrate type found underneath each intersection was recorded on underwater slates. Coral species were identified using Reef and Shore Fauna of Hawaii, Section 1: Protozoa Through Ctenophora by Maragos (1977).
Fish population density and diversity were censused using a modified Brock transect method (Brock, 1954). It is generally recognized that conducting visual transects using SCUBA gear is one of the most effective ways to assess fish populations over nearshore, rocky intertidal or shallow reef habitats where collecting gear such as nets cannot be employed readily (Dewees, 1981; Bortone and Kimmel, 1991). Visual census techniques are advantageous because they do not disturb the habitat and are minimally disruptive to the organisms. The most severe limitation of visual estimates is underestimation of real abundance and diversity patterns. This is due in part to the cryptic nature of reef dwellers and the structural complexity of the reef ecosystem (Bortone and Kimmel, 1991). Therefore, emphasis in this report is placed on relative patterns at each of the selected sites over time.
Three 50-meter lines were laid out in a parallel arrangement, separated by 5 meter intervals which created two sample areas each 250m2. These lines were spooled out from the same underwater reference point used for the quadrat work. A 10 meter rope tethered to the two end divers was used to maintain the correct width for the transect area. The third diver swam in the center and laid out the dividing transect line while maintaining a compass heading. After the lines were positioned, the researchers returned to the start of the transect and allowed 10 minutes for the fish to acclimate. Two divers then proceeded down each corridor of the transect, and recorded the number of every species of fish seen.
Data were tabulated on an underwater slate using common names. All fish identifications were standardized using the Guide to Hawaiian Reef Fishes by Randall (1985) and Shore Fishes of Hawaii by Randall (1996). Morning and afternoon samples were collected for each day of diving. After each dive, the data were transcribed from the underwater slates into a notebook for later computer entry.
Water quality characteristics at each site included; temperature, salinity, and turbidity (visibility). Temperature was measured using a handheld thermometer in the field. Water samples were collected and later analyzed for salinity using a refractometer. Horizontal visibility was measured using a secchi disk (diameter ~ 40cm) stretched between 2 divers at both the surface and bottom.
Physical parameters such as sedimentation and water motion have been monitored at the 4 long-term core areas since 1996. Sedimentation was measured using 6 sediment traps at each site. Each trap consisted of a 2" X 6" PVC tube capped at one end and placed on the bottom in planter trays that were anchored to the substrate. Sediment traps were exchanged once a month and then filtered, dried and weighed to determine quantity of sediment collected in mg/cm 2 /day. The water motion experiments were conducted by measuring the rate of dissolution for plaster of Paris clod cards in the field against a set of control cards in buckets not subjected to water movement. Preweighed clod cards are deployed once a month for a 6-hour time interval at each site and later dried and reweighed to calculate the dissolution rate.
Data analysis consisted of computer entry into MS-Access, indexed by survey number for all of the parameters measured. Thus, each survey contained information on coral coverage, fish density, physical parameters and trophic structure.
INSTRUMENT TYPES: 1) Temperature was measured using a hand-held thermometer in the field. 2) Water samples were collected and later analyzed for salinity using a refractometer. 3) Horizontal visibility was measured using a secchi disk (diameter ~ 40cm)
REFERENCES:
Bortone, S.A. and J.J. Kimmel, 1991. Environmental assessment and monitoring of artificial habitats. In: Artificial Habitats For Marine and Freshwater Fisheries. Ed. W. Seaman, Jr. and L.M. Sprague. Academic Press, Inc. 177-236.
Brock, V.E., 1954. A preliminary report on a method for estimating reef fish populations. Journ. Wild. Management. 18 (3): 297-308.
Coyer, J. and J. Witman, 1990. The Underwater Catalog. A Guide to Methods in Underwater Research. Shoals Marine Laboratory.
Dahl, A. L., 1981. Monitoring Coral Reefs for Urban Impact, Bulletin of Marine Science, 31(3):544-551.
Dewees, C.M., (Ed) 1981. Guidelines for Marine Ecological Surveys: Nekton. Sea Grant California, Marine Advisory Publication.
Maragos, J.E., 1977. Order Scleractinia, stony corals. In:Reef and Shore Fauna of Hawai'i, Section 1: Protozoa Through Ctenophora. B.P. Bishop Museum Spec. Pub. 64 (1):158-241.
Randall, J.R., 1985. Guide to Hawai'ian Reef Fishes. Harrowood Books, Newton Square, PA.
Randall, J.R., 1996. Shore Fishes of Hawai'i. Natural World Press, Vida, OR.
Reed, A.S., 1980. Sampling and Transecting Techniques on Tropical Reef Substrates. pp. 71-89. In: Environmental survey techniques for coastal water assessment. Conference Proceedings. University of Hawai'i Sea Grant College program. Cooperative Report UNIHI-SEAGRANT-CR-80-01.
Database provided as MicroSoft Access (version 97). NODC LO extracted tables as both MS Excel97 and ASCII text (comma-delimited) files.
subdirectory nodcmeta/ size filename comment 12599 mauicr_pcc.meta NODC metadata form subdirectory doc/ size filename comment 75104 Earth98.htm HTML, Saving Maui's Reefs by Eric Brown 851742 Earth98.ps PostScript, same 37171 Earth98.txt ASCII text, same subdirectory data/ subdirectory access/ size filename comment 9062400 Reef.mdb MS Access database (total dataset) (fields in tables described below)
subdirectory excel97/ "MS Excel97 extractions by NODC LO" subdirectory queries/ size filename comment 12560896 Pat_all_fish_coral.xls species counts 112128 Pat_fish_feed.xls fish behavior 153088 Pat_physical.xls physical data
subdirectory tables/ "Tables as defined by originator" size filename comment 86528 DiveMaster.xls when,where,who 11776 Location.xls where 6589952 RunDetail.xls transect,observer,quadrant 764416 RunDetail_ExportErrors.xls uncertain 10240 RunDetailtemplate.xls uncertain 9728 Survey.xls uncertain 830976 TransectRuns.xls species counts, etc 10240 TransectRunstemplate.xls uncertain 78336 feeding.xls fish behavior 108544 physc_data.xls physical data 47104 speciescode.xls description of species codes
Subdirectory txt/ "mirrors subdirectory excel97/ except all ASCII text files delimited by commas and with filename extensions as *.txt"
MS ACCESS DATABASE DESCRIPTION- file: Reef.mdb Tables (* denotes keywords): Table_Name Field_name ------------------ ------------------------------------------------- DiveMaster Survey* (number), Date, Location* (code), Time Location Location* (code), Dive site (name) TransectRuns TransectRunId (number)*, Survey*, Transect, Qlocation, Observer, Run/Quadrat RunDetail ID, TransectRunId*, Sp Code*, Number, SumofRun, p, logp Species Codes Sp Code*, Common Name, Species Name, Family, Two Letter Code, Trophic, Mobility, Endemic Fish Feed Survey*, Transect, Surface/Bottom, Seen/Feed, Sand/Food, Sp Code, Observer Physical Data Survey*, Transect, Temp-Surf (deg C), Temp-Bott (deg C), Sal-Surf (ppt), Sal-Bott (ppt), Vis-Surf (m), Vis-Bott (m), Oxy-Surf (ppm), Oxy-Bott (ppm), pH-Surf, pH-Bott, Nit-Surf (umol), Nit-Bott (umol), Phos-Surf (umol), Phos-Bott (umol)
Codes: 1) Trophic: (H,D, Z, Sl, P, MI, C, Sl/O) H= Herbivore, D=Detrivore, Z=Zooplanktivore, SI=Sessile Invertebrate, P=Piscivore, MI=Mobile Invertebrate, C=Coralivore, SI/O=Sessile Invertebrate/Omnivore 2) Endemic (E:endemic, N: not endemic, Y/N: both categories) 3) Mobility (R, S1, S2, T) These are mobility guilds set up by Jim Parrish and Alan Friedlander (1997). R = residents S1= semi-vagile species type I with mobility of 10's m S2= semi-vagile species type II with mobility of 100's m T= transients
EXTRACTIONS FROM THE MS ACESS DATABASE
1) Pat_all_fish_coral (.xls or .txt)
Field 1: survey number Field 2: survey date, ignore the 0:00:00 Field 3: ignore 12/30/99, but following number is time in Hawaiian Standard Time, e.g. 9:32:00 Field 4: location code Field 5: location name (dive site) Field 6: Transect Field 7: Qlocation (These are locations along the transect line where the Quadrat was placed. For example, 56L would refer to meter 56 on the left side of the line when starting from the 0 meter reference mark.) Field 8: Observer (initials) Field 9: Run/Quadrat Field 10: Species Code (see /data/txt/tables/speciescode.txt) Field 11: Number of Species sited Field 12: SumofRun@ Field 13: p@ Field 14: logp@
@These fields are used to generate values for the Shannon-Wiener diversity index and evenness using an update query.
2) Pat_fish_feed (.xls or .txt)
Field 1: survey number Field 2: survey date, ignore the 0:00:00 Field 3: ignore 12/30/99, but following number is time in Hawaiian Standard Time, e.g. 9:32:00 Field 4: location code Field 5: location name (dive site) Field 6: Transect Field 7: Surface/Bottom (1:surface 0:bottom) Field 8: Seen/Feed (1:seen 0:feed) Field 9: Sand/Food (1:sand 0:food) Field 10: Species Code (see /data/txt/tables/speciescode.txt) Field 11: Observer (initials)
3) Pat_physical (.xls or .txt)
Field 1: survey number Field 2: survey date, ignore the 0:00:00 Field 3: ignore 12/30/99, but following number is time in Hawaiian Standard Time, e.g. 9:32:00 Field 4: location code Field 5: location name (dive site) Field 6: Transect Field 7: Temp-Surf (deg C) Field 8: Temp-Bott (deg C) Field 9: Sal-Surf (ppt) Field 10: Sal-Bott (ppt) Field 11: Vis-Surf (m) Field 12: Vis-Bott (m) Field 13: Oxy-Surf (ppm) Field 14: Oxy-Bott (ppm) Field 15: pH-Surf Field 16: pH-Bott Field 17: Nit-Surf (umol) Field 18: Nit-Bott (umol) Field 19: Phos-Surf (umol) Field 20: Phos-Bott (umol)