The Geomorphology Habitats and Mapping of the Hawaiian

The Geomorphology, Habitats, and Mapping of the Hawaiian Archipelago Joyce Miller and John Rooney NOAA Pacific Islands Fisheries Science Center Coral Reef Ecosystem Division, Pacific Islands Benthic Habitat mapping Center

Outline • Hawaiian-Emperor chain formation history • Sea-level dynamics • Reef and shoreline development • Mapping, habitats and applications • On-going work Photo of FFS Corals by J. Kenyon

Hawaii-Emperor Chain ● 6, 126 km long ● Older to the NW: Meiji 85 Ma old , Kure ~30 Ma, Nihoa 7. 2 Ma ● 129 volcanoes, 104 islands, 39 islands > 1 km ● 1 island/time 85 -34 Ma, no islands 30 -34 Ma, multiple islands after Lisianski (23 Ma) ● Pacific Plate (Clague, 1996) ~7 cm/yr, 85 – 5 Ma ~10 cm/yr, ~5 Ma – present ● Moving Hotspot? (Tarduno, et al. , 2003 ) Volcanos No. / Ma Spacing (km) Emperor Chain 1. 1 57 NWHI 1. 7 45 MHI 4. 0 30

Hawaiian Hotspot

Vertical Tectonics

Original Size of Hawaiian Islands 20 15 10 5 0 Yellow areas around banks and islands represent calculated areas of original islands as presented in Price and Clague (2002), How old is the Hawaiian biota? Midway Subsidence ~0. 024 m/1000 yrs. (Grigg, 1997) Slow Subsidence Erosion Rock Outcrop H 1 Coral Cap o Uplift H 1 Subsidence H 2 o 7 7 o D x Tan 7 D Subaerial Volcanic Shield Sea Surface Break in Slope (subsides to -1000 -1500 m) Submergence/Atoll Figure after Price and Clague, 2002. Post-Erosion Ma 1. 9 – 2. 6 m/1000 yrs 25 2. 5 -2. 8 m/1000 yrs 30 Post-Subsidence Pre-Subsidence H 1

Figure from C. Fletcher, Coastal Geology 420

Late Quaternary Sea Level and Reef Development Interglacial Periods (High sea level) Glacial Periods (Low sea level)

Holocene Sea Level Rise (mm/yr) Period FFS Midway Oahu 1905 – 2003 NA NA 1. 47 1947 – 2003 NA 0. 58 1. 37 1974 - 2001 1. 35 2. 95 0. 65 1992 - 2001 7. 42 7. 71 -3. 97 ● Holocene Trangression ● Kapapa mid-Holocene highstand

Big Island Reef Terraces • Mapping data collected by NOAA and MBARI show major terraces at 150 and 400 m on the W. Kohala Coast. Other locations on Hawaii may or may not have reefs at similar levels. • Webster et al. , 2006, conclude that the 400 m reef was initiated about 220, 000 yrs ago and the reef drowned during deglaciation at ~134, 000 yrs ago. • Webster et al. , 2006, conclude that the 150 m was initiated about 126, 000 yrs. ago and was drowned during de-glaciation 12, 000 – 14, 000 yrs. ago, perhaps by a meltwater pulse event. • Reef sequences on the rapidly subsiding island of Hawaii are relatively straightforward to understand because deeper reefs are generally older than shallow ones. 400 m terrace 150 m terrace

astal sea level s ago. ef – Some ent to areas, 220, 000 Hawaii -- -20 to 0 yrs ago. t -49 to ugged hs seen in Information from C. Fletcher, Geology 420 Shorelines dominated by sea level change are much more complex, because ages are not sequential. Midway Terraces

Mapping, Habitats, and Applications Coral Reef Ecosystems Protected Species Research Essential Fish Habitat Management Needs (e. g. Boundaries, Charts) Resources Data Synthesis and Integration

Mapping Techniques • Satellite/aerial imagery and estimated depths • LIDAR (airborne) – bathymetry and backscatter • Acoustic techniques – bathymetry and backscatter • Optical validation

Coral Studies at Kure Atoll Geomorphic Habitat % Coral Cover Predicted Net Accretion Fore Reef/Pass 16 1. 7 (mm/yr) Back Reef 27 1. 5 (mm/yr) Lagoonal Reef 27 3. 9 (mm/yr) Mean (weighted) 20 2. 1 (mm/yr) Reef Crest & RR ? ? ?

Whaleskate Is. , FFS - 1963 Whaleskate Is. , FFS - 2002 Sealevel or Transport Change?

Habitat Analysis and Sampling Protocols Which Parameters, At What Scales? Bathymetry (depth) • Slope • Rugosity, complexity • Bathymetric Position Index (Crests, Flats, Depressions, …) • Variance (variability of signal) Backscatter • Hardness Backscatter or Hard/Soft • Roughness • Variance (variability of signal) Rugose vs. Smooth, Scale? IKONOS imagery. Integration of different data types • Classifications • Estimated depths • Variance (variability of signal) Fledermaus 3 -D Image of FFS Bank

Study of MHI and NWHI Banks Penguin Bank, MHI Low Relief Structures On Top W. Nihoa NWHI Brooks Banks, NWHI Sand Deposits Essential Fish Habitat (EFH) defined by: Depth Slope Backscatter Values Rugosity? Bot. Cam Studies MHI Synthesis, Whale Habitat Low rugosity Low slope

MHI & NWHI Mapping Synthesis Work Collaborative effort between UH SOEST & NOAA, Mapping > 100 m almost complete, < 100 m – AHI or LIDAR work to do, 50 m grid at www. soest. hawaii. edu/hmrg

NWHI-MNM Operational Statistics and Estimates Multibeam Completed 2002 -2006 (km 2) (Days) Deep (>100 m) 38, 367 25 Shallow (20 -100 m) 3, 709 124 Totals Optical 42, 076 149 Estimate To Complete (Days) 70 285 355 Deep (>20 m, towed camera): 3733 still photos; 191 videos, ~ 2 km each Shallow (≤ 30 m, towboard cameras): 135+ tracks, ~2 km each, reoccupied biennially

Management & Research Questions • Sea level changes and the effects on geology, beach formations, habitats, ages of banks… • How much coral is there, where does it occur? • Design of sampling protocols. Hard vs. soft, rugose vs. smooth, variability of parameters? • Evolution of submerged banks. How much EFH? Location? Protected areas? • Location of resources: sand -- for beaches, construction, protected species, anchorages. • Data for boundaries and nautical charts. • Habitats: whales, bottom fish, reef fish, lobsters. • Other questions? ?

Future Research ● Mapping a. Continue MB data collection b. Bathy and backscatter processing c. Bathy and backscatter analysis d. IKONOS, MB or LIDAR for shallow depths? ● Groundtruth a. Develop ROV/AUV capabilities b. Optical data collection & processing c. Coring ● Data Interpretation and Integration a. Defining appropriate products for specific needs b. Interpretation of individual data types c. Integration of disparate data types d. Creation of “seamless” habitat maps for many different species

Aloha What research or management questions that can be quantified by mapping techniques are important for your work? Websites: http: //www. soest. hawaii. edu/PIBHMC http: //www. pifsc. noaa. gov/cred For information contact: John. Rooney@noaa. gov Joyce. Miller@noaa. gov