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NOAA Office of Ocean Exploration Quick Look Report

Expedition Title: [Submarine Canyon and Scavenger Communities in the
Main and Northwest Hawaiian Islands]{.underline}

+------------------+---------------------------------------------------+
| Results (please  | Details (please describe any novel discoveries in |
| check all        | the discipline, answers such as "possible,        |
| disciplines in   | awaiting data analysis" and "no apparent          |
| which this       | discoveries" are acceptable)                      |
| cruise collected |                                                   |
| data)            |                                                   |
+------------------+---------------------------------------------------+
| Bathymetric      | (please note total area mapped and technology     |
| Mapping          | employed, e.g. multibeam, side scan, etc.)        |
|                  |                                                   |
|  Yes x No       |                                                   |
+------------------+---------------------------------------------------+
| New Species      | (please note number, type, and significance ,i.e. |
| Discovered       | radically new vs. slight adaptation of known      |
|                  | species)                                          |
|  Yes  No       |                                                   |
|                  | REMAINS TO BE DETERMINED PENDING ANALYSIS OF      |
|                  | MEGA- AND MACRO-FAUNAL SAMPLES                    |
+------------------+---------------------------------------------------+
| Bio-prospecting  | (please note number, type, and potential use of   |
|                  | new compounds discovered)                         |
|  Yes x No       |                                                   |
+------------------+---------------------------------------------------+
| Habitat Range    | (please note species discovered in new habitats   |
| Extended         | and how far from previous range were they found)  |
|                  | We observed several 3 m long false cat sharks     |
| x Yes  No       | (*Pseudotriachis acrages)* which have been        |
|                  | previously reported from the Main Hawaiian        |
|                  | Islands but have never been observed from         |
|                  | submersibles in this region. We also trapped      |
|                  | several snubnosed Eel *Simenchelys* for which we  |
|                  | can find no report from this region. Other        |
|                  | reports await further analyses.                   |
+------------------+---------------------------------------------------+
| Chemical         | (please note new or unusual chemical properties   |
| Processes        | such as methane seeps, hypersaline pools, vents,  |
|                  | etc. observed)                                    |
|  Yes x No       |                                                   |
+------------------+---------------------------------------------------+
| Geologic         | (please note new or unusual geologic processes    |
| Processes        | that may impact scientific understanding of the   |
|                  | region)                                           |
|  Yes x No       |                                                   |
+------------------+---------------------------------------------------+
| Physical         | (please note new or unusual oceanographic         |
| Processes        | processes that may impact scientific              |
|                  | understanding of the region)                      |
|  Yes  No       |                                                   |
+------------------+---------------------------------------------------+
| Sub/ROV/AUV      | (please note name, type, and cumulative hours of  |
| Dives            | bottom time for each platform / if available      |
|                  | please provide average working time per dive for  |
| x Yes  No       | each platform / please note if new depth records  |
|                  | were set)                                         |
|                  |                                                   |
|                  | !2 Pisces IV dives with an average duration of    |
|                  | about 8 hours.                                    |
|                  |                                                   |
|                  | 9 RCV 150 dives with an average duration of 3     |
|                  | hours                                             |
+------------------+---------------------------------------------------+
| New Technology   | (please note any new tools developed for or       |
|                  | during this cruise, also identify first use of an |
|  Yes x No       | existing technology in a new application)         |
+------------------+---------------------------------------------------+
| Maritime         | (please note discoveries impacting knowledge of   |
| Cultural         | the past, i.e. number and type of shipwrecks)     |
| Heritage         |                                                   |
|                  |                                                   |
|  Yes x No       |                                                   |
+------------------+---------------------------------------------------+
| Outreach         | (please describe outreach channels, e.g. web,     |
|                  | port call, etc., used in this project)            |
| x Yes  No       |                                                   |
+------------------+---------------------------------------------------+
| Students         | (please note the number and level of students on  |
| Involved         | the expedition)                                   |
|                  |                                                   |
| x Yes  No       | Two undergraduate students participated in the    |
|                  | expedition.                                       |
+------------------+---------------------------------------------------+
| M                | (please identify the formal disciplines           |
| ultidisciplinary | represented in the science party)                 |
|                  |                                                   |
|  Yes  No       |                                                   |
+------------------+---------------------------------------------------+
| Exploration of   | (please note if the area of operations had been   |
| New Regions      | previously studied, if so please check no and     |
|                  | approximate as slight, moderate or significant,   |
| x Yes  No       | the level of knowledge before the cruise)         |
|                  |                                                   |
|                  | These were the first dives into submarine canyons |
|                  | in the NWHI's.                                    |
+------------------+---------------------------------------------------+

Ocean Exploration Quick Look Report Required Elements

The Office of Ocean Exploration (OE) does not require a specific Quick
Look Report format. Reports submitted under other requirements (e.g.
Cruise Summary Report (CSR) or Fisheries-Oceanography Coordinated
Investigations (FOCI)) are acceptable. In all cases Quick Look Reports
submitted to OE should contain the following elements:

**Project title** (as listed in original proposal)

Submarine Canyon and Scavenger Communities in the Main and Northwest
Hawaiian Islands

**Principal Investigator and institution** (as listed in original
proposal)

Dr. Craig Smith, University of Hawaii, Manoa

**Expedition title** (working name of the cruise)

NWHI's submarine canyons

# Expedition dates and itinerary

September 3, 2003, departure from Honolulu

September 4-9, Dives at Nihoa Island

September 13-18 Dives at Maro Reef

September 26 -- Arrive Midway Island

September 28 -- Return to Honolulu by air

November 6 -- KOK returns to Honolulu with samples

# Chief Scientist and institution 

Dr. Craig Smith, University of Hawaii, Manoa

# Co-sponsors / partners / participating organization

**Vessel Identification** (if applicable)

Ka'imi'kai O Kanaloa

# Embarked vehicles, sensors, and tools of significance

We launched the Pisces IV submarine and the RCV 150 ROV from the R/V
Ka'imi'kai O Kanaloa. Data was acquired using visual surveys, video
surveys using digital and analog cameras, sediment cores, scavenger
traps, and scoop-nets.

**Geographic area of operations** (identify common name such as North
West Hawaiian Islands as well as boundary coordinates for the area)

Nihoa Island (23°10, 161°53) and Maro Reef (25° 32, 170° 24), Northwest
Hawaiian Islands

# Summary of Cruise Objectives

We explored the roles of submarine canyons as hot spots of benthic
production, juvenile fish habitat and centers of biodiversity on the
slopes of the Northwest Hawaiian Islands. Using The Pisces IV
submersible and an ROV, we examined macrofaunal, megafaunal, and
scavenger community structure within two canyons off atolls in the
Northwest Hawaiian Islands (Nihoa Island and Maro Reef). We conducted
video and photographic surveys, core sampling, and bait and trap
deployments at multiple depths within each canyon, and along open-slope
reference transects, to quantify habitat characteristics and community
structure inside versus outside of canyons. We will also examine benthic
food-web structure inside and outside canyons using stable isotope
(^13^C and ^15^N) analyses.

**Summary of Cruise Operations** (A good summary would identify as many
of the following elements as possible for each "operation." Table
formats are ideal for this aspect of the report: data type collected /
time / position / ID tag /operation type /dive tracklines / depth
/comments)

Pisces IV dives replicated the same mission at different sites (canyon
or slope) and depths on each dive. Depths investigated included 350,
650, and 1000 m. At each depth scavenger traps were deployed for 24
hours, scavenger response to bait parcels was observed, sediment samples
were collected, and visual and video transects were run.

Pisces IV

Dive \# Date Location Depth range Position

90 9/4/2003 Nihoa Canyon 350-700 m 23°10, 161°53

91 9/5/2003 Nihoa Canyon 650-1200 m 23° 10, 161° 53

92 9/6/2003 Nihoa Canyon 350-1200 m 23° 11, 161° 52

93 9/7/2003 Nihoa Slope 300- 400 m 23° 11, 161° 52

94 9/8/2003 Nihoa Slope 300-400 m 23° 12, 161° 52

95 9/9/2003 Nihoa Slope 650-1200 m 23° 11, 161° 42

97 9/13/2003 Maro Canyon 650-1050 m 25° 32, 170° 24

98 9/14/2003 Maro Slope 750-1100 m 25°31, 170°24

99 9/15/2003 Maro Canyon 350-680 m 25° 30, 170° 25

100 9/16/2003 Maro Canyon 350-650 m 25° 31, 170° 25

101 9/17/2003 Maro Slope 650-1000 m 25° 28, 170° 22

102 9/18/2003 Maro Slope 650-1000 m 25° 29, 170° 21

Navigational limitations of the ROV resulted in most dives being
conducted outside of the canyons. Video data will be analyzed for
species diversity and density of magafaunal fishes and invertebrates.
Video data will also be analyzed for substrate type and percent cover of
algal detritus.

RCV 150

Dive \# Date Location Depth Position

218 9/4/2003 Nihoa Canyon 130-350 m 23°11, 161°43

220 9/5/2003 Nihoa Slope 430-600 m 23°11, 161°43

221 9/7/2003 Nihoa Slope 350-380 m 23°11, 161°43

222 9/8/2003 Nihoa Slope 350-650 m 23°11, 161°43

224 9/13/2003 Maro Slope 350-680 m 25°25, 170°21

225 9/14/2003 Maro Slope 320-550 m 25°25, 170°21

226 9/15/2003 Maro Canyon 350-700 m 25°25, 170°21

227 9/16/2003 Maro Canyon 350-680 m 25°30, 170°25

228 9/17/2003 Maro Slope 350-680 m 25°30, 170°25

**Milestones Achieve** (This section of the report should amplify the
information provided in the official OE cover sheet summary of results)

The first cruise for this project, to study canyon and slope habitats in
the Northwest Hawaiian Islands, took place between September 3rd and
28^th^ aboard the research vessel Ka'imi'kai O Kanaloa (KOK). The cruise
was overwhelmingly successful in terms of submarine exploration,
hypothesis testing, data collection, and dives made. All 12 Pisces IV
dives went according to plan, and we made an additional 8 dives using
the ROV RC-150.

Samples and data collected included quantitative megafaunal surveys
(using video with the ROV and direct observations with Pisces IV), tube
cores for infaunal and grain size analyses, quantitative observations of
scavenger aggregations at standard baits, and trapping of scavengers
with baited traps. These data will be used to examine differences in
submarine and scavenger communities by depth and habitat (inside and
outside of submarine canyons). Megafaunal assemblages will be analyzed
for abundance, community structure, and diversity; infauna for
abundance, diversity, and biomass; and scavengers for species
assemblages, population genetics, and stable isotopes for trophic
analysis.

All of our physical samples, including sediments, scavengers, and
videotapes were aboard the KOK, and not be available for analysis until
November 6^th^; however, some preliminary analyses of megafaunal
distributions were made at sea. These indicate that both fish and
invertebrate megafaunal abundance and diversity increased in moving from
the open slope into canyons, and in moving from shallow to deeper
depths. As predicted, megafauna appear to be enhanced in regions with
abrupt topography, which is much more common inside canyons.
Unexpectedly, we found apparent enhancement of benthic populations by
concentration of macrophyte detritus within the canyon investigated off
Nihoa Island. The concentration of green algae detritus off a small, low
island within a canyon with a deep (330 m) head located far from shore
is remarkable. The increase in megafaunal abundance with depth was also
very surprising because the flux of organic matter, and biomass of
seafloor communities, normally declines exponentially with depth down
slope. We hypothesize that the relatively low biomass at 350 m (relative
to deeper depths) results from high predation pressure from
shallow-water predators (e.g., the amberjack *Seriola dumerili*) that
occasional forays into deep water. On many occasions, we observed
amberjacks feeding on sluggish deepwater fishes at depths down to \~ 400
m, even though amberjacks are generally considered to be epipelagic
predators. In addition, fish biomass at our deeper stations (650-1000 m)
may be enhanced by the provision of prey in the form of vertical
migrators (small nekton crustaceans and fishes) that feed in surface
waters at night, and migrate below the depth of light penetration (\~600
m) during daytime.

The scavenger communities were surprisingly large and extremely active,
suggesting a remarkably large carrion flux to the slope around the
Northwest Hawaiian Islands. Bait parcels at our 650 and 950 m stations
typically attracted a number of large rays and sharks, totaling several
100 kg in biomass, within the first 0.5 hours. Scavengers included at
least three species not previously observed by submersible in Hawaiian
waters; the eel *Simenchelys parasitica* (first Hawaiian collection), a
3 m-long, six gill shark, *Hexanchus griseus,* and the 3-m false cat
shark *Psuedotriachis acrages.* Other major scavengers included
lysianassid amphipods, several species of large shrimp (genus
*Heterocarpus* ), and the voracious ray, *Plesiobatis daviesi.*
Scavengers were larger, more abundant and more diverse inside canyons.
Scavengers were also more abundant at our deeper stations (650-950 m),
consistent with an expected concentration of biomass in this depth
range.

# Sample log entries

**Summary of Digital Data Collected** (Identify volume in MB/GB/TB etc.
and type of data collected. Be as explicit as possible, e.g. identify
high definition video as opposed to simply video.)

Video data was recorded on each Pisces IV dive using both digital and
analog color camera's.

Analog color video was recorded on each RCV 150 dive.

# Summary of outreach and educational activities

Outreach and educational activities were supported through web-sites
produced by NOAA-OE personnel using information, photo's and video which
we supplied. We also participated in demonstrations and exhibits aboard
the KOK for visiting school groups in Honolulu on November 6^th^.