Hohonu Moana: Exploring Deep Waters off Hawaiʻi






Daily Updates

Access the 2015 Hohonu Moana: Exploring Deep Waters off Hawai’i Daily Updates RSS Feed here:
2015 Hohonu Moana: Exploring Deep Waters off Hawai’i Daily Updates
NOAA RSS 2.0 Feed

 


 

NOAA Ship Okeanos Explorer makes a stop at Kilo pier to offload the ROVs at the conclusion of the 2015 field season

NOAA Ship Okeanos Explorer makes a stop at Kilo pier to offload the ROVs at the conclusion of the 2015 field season. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 30, 2015

Return to Pearl Harbor: Mission Complete

After a very successful mission surveying the deepwater habitats at Johnston Atoll, NOAA Ship Okeanos Explorer ship returned to Pearl Harbor, Hawaii, this morning. On our way into port, we stopped at the Kilo pier to offload the ROVs. The ship then shifted to Ford Island for the rest of mission demobilization. With the conclusion of Leg 4, the 2015 Hohonu Moana expedition is complete! Thanks for joining our expedition and stay tuned for more details about what 2016 has in store for us!


 


 

 

 

Rough seas break over the bow of NOAA Ship Okeanos Explorer during the transit back to Honolulu, HI.

Rough seas break over the bow of NOAA Ship Okeanos Explorer during the transit back to Honolulu, Hawaii. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 27 - 29, 2015

Transit to Honolulu

NOAA Ship Okeanos Explorer spent the last three days transiting back to Honolulu, Hawaii – a trip that should have only taken two days, lengthened by heavy seas. We collected mapping data for as long as the data was of good quality, but after awhile, the multibeam system and subbottom profiler were secured. We continued to run the EK60 throughout the transit, but the data was patchy. On-board personnel started to wrap up projects and began the process of demobilization.


 


 

 

 

Throughout the dive at Guyot Ridge, D2 observed a diversity of deep sea corals and sponges.

Throughout the dive at Guyot Ridge, D2 observed a diversity of deep-sea corals and sponges. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 26, 2015

18°, 07.020' N; 169°, 00.138' W

Leg 4 Dive 13: Guyot Ridge

Today’s dive explored a guyot ridge along the northwest end of the Karin Seamounts. We had a very a successful dive, returning with two rocks and one chrysogorgiid octocoral after conducting five midwater transects during the ascent of the ROVs. The dive began on the slope about 240 meters below the plateau in an area of high coral diversity with at least seven different species of octocorals. The bottom was steep and very little sediment was observed. Corals and sponges were regularly observed as we climbed the steep slope, along with many associates. We estimate at least seven different morphotypes of sponges were documented during the dive. Other interesting observations included several swimming ribbon worms; a Swima polychaete; unusual crinoids; and several rocks with large barnacles. Four individual fish were seen, each of a different family – a rattail, cusk eel, cutthroat eel, and a codling. As on most dives during this expedition, exposed hard bottom that appeared heavily encrusted with manganese was the norm. Some of the terrain was very steep with pinnacles. The edge of the plateau showed a sharp transition from corals to a high abundance of sponges, including at least seven genera on the top. Midwater transects documented several jellyfish and two mid-water fish. 


 


 

 

 

Ten minutes into the dive, our science team found this unidentified candelabrid solitary hydroid. After the expedition concludes and we are able to get this sample back to the lab, we will have a better idea about exactly what it is.

Ten minutes into the dive, our science team found this unidentified candelabrid solitary hydroid. After the expedition concludes and we are able to get this sample back to the lab, we will have a better idea about exactly what it is. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 25, 2015

17.61467 N, 169.64495 W

Leg 4 Dive 12: Abyssal Ridge

Today we celebrated the one-year anniversary of the Pacific Remote Islands Marine National Monument with the deepest dive ever conducted in the monument. Dive 12 explored a ridge feature west of Karin Ridge, starting from a depth of 4,241 meters. After only about 10 minutes on the seafloor, our science team was stumped by a very unusual hydroid species. As ROV Deep Discoverer (D2) continued up slope, we documented several different species of sponges and sea cucumbers, a few brittle stars, a brisingid sea star, squat lobsters, crinoids, barnacles, ribbon worms, and two pregnant crustaceans (a possum shrimp and a large isopod). We also encountered several fish including cutthroat eels and cusk eels. Sponges were by far the most abundant organism observed during the dive.


 


 

 

 

One organism's trash is anther's treasure- these crinoids have taken up residence on a tall dead sponge stalk to give them better access to food in the water column.

One organism's trash is another's treasure—these crinoids have taken up residence on a tall dead sponge stalk to give them better access to food in the water column. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 24, 2015

17.49896 N, 168.74078 W

Leg 4 Dive 11: Karin Ridge Top

Today’s dive explored the crest of a ridge extending south of one of the plateaus of the Karin Ridge. ROV Deep Discoverer (D2) began the dive at a depth of 2,170 meters in an area with sponges, anemones, crinoids, and a dandelion siphonophore. As D2 transited up the slope, we documented several more sponges, anemones, and crinoids as well as a few octocorals and fish (cutthroat eel and rattails). Midway through the dive, we encountered a field of stalked sponges and concluded the dive on a topographic high with several octocorals, including representatives from every major deep-sea octocoral families. Other fauna observed during the dive included barnacles, hydroids, an aplacophora (shell-less snail), and polychaetes. During the dive, we collected one rock and two unusual bamboo corals.


 


 

 

 

Another USO (Unidentified Swimming Organism) for the cruise. Our science team was stumped as to what this organism could be.

Another USO (Unidentified Swimming Organism) for the cruise. Our science team was stumped as to what this organism could be. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 23, 2015

16.54129 N, 168.21357 W

Leg 4 Dive 10: Mid Karin Ridge

Today’s dive investigated a ridge extending south of one of the plateaus of the Karin Ridge located 75 miles east of Johnston Atoll. ROV Deep Discoverer (D2) landed on a cemented bottom with a heavy manganese crust with bamboo corals and sponges at a depth 2,329 meters. During the dive, we encountered a diversity of deep-sea corals, with the highest density being found at the top of the feature. Also encountered during today’s dive were starfish, several predating on corals; sponges; brittle stars; squat lobsters; aplacophora; a cusk eel; a rattail; and an unknown pink organism in the water column that has stumped our science team.


 


 

 

 

At the top of the ridge feature visited during Dive 09, ROV Deep Discoverer encountered a dense and diverse deep sea coral community. In this picture alone are at least 4 different species of coral and at least 12 different colonies.

At the top of the ridge feature visited during Dive 09, ROV Deep Discoverer encountered a dense and diverse deep-sea coral community. In this picture alone are at least four different species of coral and at least 12 different colonies. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 22, 2015

16.14331 N, 167.85602 W

Leg 4 Dive 09: South Karin Ridge

ROV Deep Discoverer conducted Dive 09 along a narrow ridge just south of Karin Ridge. The dive started from a depth of 1,967 meters and transited upslope, encountering a number of crinoids, sponges, and hydroids that had colonized almost every surface. Other fauna encountered during the transect included a long-finned cusk eel, squat lobsters, a beautiful red ctenophore, octocorals, black corals, shrimp, and anemones. Densities of coral (over 20 species) and sponges (approximately 10 species) were highest at the top of the ridge feature. Several of these corals were very large, leading us to believe they were very old and this was a well-established habitat for deep-sea corals.


 


 

 

 

A rare sighting of a juvinile cutthroat eel will help our scientists learn more about the life history of these fish.

A rare sighting of a juvinile cutthroat eel will help our scientists learn more about the life history of these fish. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 21, 2015

15.59547 N, 167.74474 W

Leg 4 Dive 08: Lone Cone

Dive 08 investigated the northeast slope of a cone feature on an unnamed seamount, 30 miles north of yesterday’s dive site. ROV Deep Discoverer (D2) landed on sedimented bottom with some exposed manganese encrusted rock at 2,137 meters. As D2 moved upslope, we encountered occasional corals and sponges, shrimp, a very large unusual crinoid, a Bathytyphlops (deep-sea tripod fish with greatly reduced eyes), an arrow worm, and a diversity of echinoderms. As D2 approached the summit of the cone feature, the diversity and density of fauna increased. Over 18 species of deep-sea corals, including a diversity of black corals and octocorals were documented. At the end of the dive, we imaged a rare juvenile cutthroat eel.


 


 

 

 

A rare observation of an aplacophoran (shell-less mollusk) feeding on a bamboo coral.

A rare observation of an aplacophoran (shell-less mollusk) feeding on a bamboo coral. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 20, 2015

15.21 N, 168.06 W

Leg 4 Dive 07: Southernmost Cone

Today’s dive transited up the slopes of a pair of associated cones (one cone appearing to arise from the shoulder of the other) on an unnamed seamount/guyot plateau at the southernmost point of our expedition. Overall densities of sessile fauna were lower than observed yesterday on the “Two Cones” dive, including at the summit of the feature. However, there was a moderate diversity of corals and sponges, including several species  of octocorals, precious corals, and black corals not seen on Two Cones. Again, very few fish were seen; however, there was one new observation, of a sea toad (Chaunocops cf. melanostomus). Exciting observations from today's dive included an aplacophoran, or shell-less mollusk, actively feeding on a bamboo coral and a rarely seen stalked sponge (Caulophacus). We were able to collect three rocks, one unidentified stalked crinoid with a parasitic snail, and a fragment of a bamboo coral with a squat lobster.


 


 

 

 

During the descent on Dive 06, a 1-2 meter squid attached itself to the back of ROV Deep Discoverer (D2) and hung out there for several minutes before coming around to the front of the vehicle, allow us to get some great imagery of it.

During the descent on Dive 06, a one to two-meter squid attached itself to the back of ROV Deep Discoverer (D2) and hung out there for several minutes before coming around to the front of the vehicle, allowing us to get some great imagery of it. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 19, 2015

15.46380 N, 169.07795 W

Leg 4 Dive 06: Twin Cones

Today’s dive investigated two cone features along an extension of Hutchinson Seamount, part of the Johnston Seamounts. Dive 06 began with an eventful descent as a one to two-meter squid attached itself to the back of ROV Deep Discoverer (D2) and hung out there for several minutes before coming around to the front of the vehicle. Once D2 reached the bottom of the first cone feature and began the transit upslope, we documented a high diversity of corals including several species of octocorals and black corals, squat lobsters, anemones, sponges, brittle stars, sea star predation on bamboo corals, and crinoids. After reaching the summit of the first cone, D2 conducted a midwater transit to the second feature, documenting salps, siphonophores, and jellyfish. Fauna at the second cone was similar to the first and included octocorals, a lobster, black corals, crinoids, polychaetes, sea stars, and a very large anemone at the summit. At both features, the highest density and diversity of corals was at the top of the feature.


 


 

 

 

An unusual jelleyfish noted about halfway through Dive 05 at Deep Twin Ridge.

An unusual jelleyfish noted about halfway through Dive 05 at Deep Twin Ridge. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 18, 2015

15.63428 N, 169.48827 W

Leg 4 Dive 05: Deep Twin Ridge

ROV Dive 05 was conducted on Deep Twin Ridge, on the south side of the Johnston Seamounts in the Pacific Remote Islands Marine National Monument. ROV Deep Discoverer landed on a rubble strewn seafloor with little visible benthic fauna at a depth of 2,445 meters. Fauna throughout the dive was diverse, but sparse, with occasional large coral colonies including a bamboo coral over 14 feet tall. Also documented were a range extension for a long-finned cusk eel – potentially the first time it has ever been observed in the Central Pacific; an unusual jellyfish; octocorals; several different polychaetes; black corals; sea pens; and a diversity of echinoderms including sea cucumbers, crinoids, and a sea urchin.


 


 

 

 

During Dive 04 ROV Deep Discoverer documented this USO- Unidentified Swimming Organism.

During Dive 04, ROV Deep Discoverer documented this USO – Unidentified Swimming Organism. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 17, 2015

16.66416 N, 169.35050 W

Leg 4 Dive 04: Southeast Johnston

Today started with an early morning supply transfer to the U.S. Fish and Wildlife Service scientists that work at the Johnston Atoll National Wildlife Refuge. While the ship was in calm waters, we took advantage of the opportunity to make some adjustments to the satellite dish to hopefully improve connectivity. Unfortunately, we may struggle with this throughout the rest of the cruise. Dive 04 was conducted on the southeast side of Johnston Atoll, along a ridge that led up to a plateau feature. The dive started at 1,450 meters over a rippled seafloor with a swimming amphipod, seapen, halosaur, and eels. As D2 transited upslope, we documented several species of sponges, sea pens, octocorals with squat lobster associates, crinoids, anemones, halosaurs, eels, a toungefish, a chimera, and a predatory tunicate with a polychaete associate. Samples collected today included a unknown sponge species (1,317 meters) and a rock sample (1,272 meters).


 


 

 

 

One of the many large sponges observed during Dive 03. Look closely and you can see a small shrimp who has taken up residence in the sponge. The red dots in the image are lasers that are 10 cm apart and provide scale to help scientists determine the size of the object being imaged.

One of the many large sponges observed during Dive 03. Look closely and you can see a small shrimp who has taken up residence in the sponge. The red dots in the image are lasers that are 10 centimeters apart and provide scale to help scientists determine the size of the object being imaged. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 16, 2015

17.66277 N, 168.67827 W

Leg 4 Dive 03: Karin Ridge

Dive 03 was conducted along a deep spine feature along the Karen Ridge, northeast of Johnston Atoll, approximately 650 miles south of Honolulu, Hawaii. ROV Deep Discoverer  (D2) started the dive with an eventful descent with an abundance of life in the water column. D2 landed on a relatively flat bottom with a few swimming crustaceans, sponges, and loose rock at a depth of 3,200 meters. As D2 traveled upslope, we documented sponges, tunicates, crinoids, eels, shrimp, anemones, a stalked barnacle, several brittle stars, and a few corals, including bamboo. Three rock samples and one sponge were collected during today’s dive. Dive 03 was the first of a series of dives that will all be the deepest ever conducted in the Johnston Atoll region.


 


 

 

 

NOAA Ship Okeanos Explorer transits to Johnston Atoll- mapping their way off into the sunset.

NOAA Ship Okeanos Explorer transits to Johnston Atoll—mapping its way off into the sunset. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 14-15, 2015

Transit Mapping

Okeanos Explorer spent yesterday and today transiting to the primary operating area for Leg 4, the Johnston Atoll portion of the Pacific Remote Islands Marine National Monument. During our transit, we conducted mapping operations, collecting high-resolution data from our three sonars. The rest of our mission team spent the day training new personnel, catching up on data products, and planning for the rest of the expedition with our shore-based team.


 


 

 

 

A splendid perch observed towards the top of the pinnacle feature surveyed along the SW coast of Niihau.

A splendid perch observed towards the top of the pinnacle feature surveyed along the southwest coast of Niihau. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 13, 2015

21.80661 N, 160.28637 W

Leg 4 Dive 2: Niihau

Dive 02 of Leg 4 was conducted on a pinnacle feature on the southwest coast of Niihau. This was the first-ever exploration of this region and the main objective of the dive was to learn more about fish and precious corals located here.  ROV Deep Discoverer (D2) began the dive over pillow lava flows with some precious corals at a depth of 538 meters. During the transit upslope, D2 encountered a number of arthropods, sea stars, and other echinoderms; a diversity of corals that included bamboo corals, precious corals, gorgonians, scleractinians, and black corals; at least 12 species of fish; and a potentially undescribed species of octopus that was a rare observation at that depth. The dive ended at a depth of 312 meters amongst a diverse, dense bed of deep-sea corals. Two corals, a sea pen, and one rock sample were collected during this dive. Prior to collecting one of the coral samples, all of the ROV lights were turned off, and for the first time, D2 captured high resolution imagery of in situ bioluminescence!


 


 

 

 

ROV Deep Discoverer recovers a current meter at a dive site just south of Oahu.

ROV Deep Discoverer recovers a current meter at a dive site just south of Oahu. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 12, 2015

Leg 4 Dive 1: South of Oahu

NOAA Ship Okeanos Explorer got underway this morning with a newly repaired VSAT and generator. We conducted a short dive just south of Oahu to collect two current meters that were deployed a couple of years ago. We were also looking for an unusual black coral that was documented during the original instrument deployment. After recovering the two meters, ROV Deep Discoverer located and collected a sample of the unusual coral. Mapping operations commenced after the vehicles were secured on deck as we transited to the next dive site at Ni’ihau.


 


 

 

 

ENS Pestone obverses morning colors.

ENS Pestone obverses morning colors. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 10-11, 2015

Still in Port

Repairs on the ship's generator and satellite have been progressing since last week. We are optimistic that we will be able to get underway on Saturday. We are planning to do a little work in the Hawaiian Islands before heading towards to Johnston Atoll on Monday. Our onboard team has been catching up on backlogged work, working with the contractors on the repairs, and adjusting the remaining dive schedule to accommodate the delay.


 


 

 

 

NOAA Ship Okeanos Explorer is back at the pier in Pearl Harbor, Oahu after completing Leg 3 of the Hohonu Moana Expedition. The start of cruise leg 4 has been delayed to September 11th – tune back then to follow along as the ship begins exploration of the Johnston Atoll portion of the Pacific Remote Islands Marine National Monument!

NOAA Ship Okeanos Explorer is back at the pier in Pearl Harbor, Oahu, after completing Leg 3 of the Hohonu Moana expedition. The start of cruise leg 4 has been delayed to September 11 – tune back then to follow along as the ship begins exploration of the Johnston Atoll portion of the Pacific Remote Islands Marine National Monument! Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 4, 2015

Back in Port at Pearl Harbor

Following completion of yesterday’s dive on the S-19 submarine, NOAA Ship Okeanos Explorer made her way into port in Pearl Harbor, bringing cruise Leg 3 of the Hohonu Moana: Exploring Deep Waters off Hawaiʻi expedition to a close. Personnel spent the day processing data, writing reports, and completing cruise documentation and paperwork. During the inport period, repairs are planned on the ship’s number 4 generator, and as a result, the start of Leg 4 will be delayed by as much as a week. The anticipated cruise departure date is now September 11. Tune back then to follow along as the ship begins exploration of the Johnston Atoll portion of the Pacific Remote Islands Marine National Monument!


 


 

 

 

NOAA’s Deep Discoverer ROV shines its lights on the S-19 submarine resting ~415m deep.

NOAA’s Deep Discoverer ROV shines its lights on the S-19 submarine resting ~ 415 meters deep. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 3, 2015

Leg 3 Dive 07: S-19 Submarine

Dive 07 visited the hull of the World War I-era submarine, S-19, which now rests on the ocean bottom at 414 meters depth in the middle of a sand expanse. The vessel was intentionally scuttled by the Navy in 1938 and now serves as a relatively new feature of hard bottom habitat (~ 75 years old) for deep corals to colonize. A complete survey of the of the full deck area of the S-19 hull was conducted with attention to the deep coral community growing on it, looking for any evidence of recent arrival of the parasitic gold coral. Observations on the condition of the S-19 itself indicate the submarine is relatively intact, aside from features removed prior to disposal, and is resting on its midship section. Scour craters exist beneath both the unsupported bow and stern. Deterioration, flexing, and active corrosion of the hull and weather deck is very low compared to other sunken submarines. The survey was particularly useful for understanding the salvage operations completed prior to sinking. Diesel engines, superstructure, anchor, rudder and stern dive planes, propellers and shafts, and rotating bow planes had all been removed before the sub was scuttled. In addition to surveying the submarine and deep coral community growing on it, a flow meter instrument deployed in 2013 was recovered from the stern of the S-19, and the team practiced deployment and recovery of a mock-up tilt meter instrument to inform future operations.


 


 

 

 

NOAA’s Seirios camera sled images ROV Deep Discoverer shining its lights and cameras on a very dense community of large, presumably very old, colonies of bamboo coral (isididae) that were found on the ridge crest of Ellis seamount.

NOAA’s Seirios camera sled images ROV Deep Discoverer shining its lights and cameras on a very dense community of large, presumably very old, colonies of bamboo coral (isididae) that were found on the ridge crest of Ellis Seamount. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 2, 2015

Leg 3 Dive 06: Ellis Seamount

Dive 06 was the first dive ever conducted on Ellis Seamount, located in the Geologist Seamounts group. The objective of this dive was to survey a rift zone ridge coming off the northern end of the seamount for corals and sponges, to gather more information on whether high-density communities can be found on ridge topography. From beginning to end, the dive observed high densities of coral colonies with the most dominant taxa being species of Keratoisis, Isidella, and Acanella which were present as full-size, mature colonies throughout the survey track. A total distance of roughly 800 meters was traveled during the dive.  


 


 

 

 

High density coral community encountered as the ROV proceeded up the slope of a pinnacle feature located on the ridge crest.

High-density coral community encountered as the ROV proceeded up the slope of a pinnacle feature located on the ridge crest. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
September 1, 2015

Leg 3 Dive 05: Swordfish Seamount

Dive 05 of this expedition was the first dive ever conducted on Swordfish Seamount, located in the Geologist Seamounts group. The dive plan was to survey the upper crest of the ridge-shaped summit at a depth of approximately 1,000 meters to search for corals and sponges. The dive started on the west flank of the ridge at 1,071 meters where very few animals were encountered. The ROV then proceeded to the crest, still seeing low abundance. A pinnacle feature was present on the ridge crest and as the ROV proceeded up the northern slope of the pinnacle to its summit at 954 meters, a high-density coral community was encountered. As the ROV came over the summit and proceeded down the southern side to a depth of 1,074 meters, abundance again decreased. The full planned distance of the dive track was achieved and exceeded, for a total distance of 800 meters traveled during today’s dive.


 


 

 

 

An extremely old Farrea nr occa erecta sponge found ~2660 m deep at McCall Seamount. This species has two types of morphologies - a bushy type and a stalked type (shown here). A fairly large number of dead colonies of this sponge were observed during the dive - this was the only live sponge of this type encountered.

An extremely old Farrea nr occa erecta sponge found ~2,660 meters deep at McCall Seamount. This species has two types of morphologies – a bushy type and a stalked type (shown here). A fairly large number of dead colonies of this sponge were observed during the dive – this was the only live sponge of this type encountered. Click image for credit and larger view.

camera icon Video highlights from Leg 3 Dive 4

 


NOAA Ship Okeanos Explorer
August 31, 2015

Leg 3 Dive 04: McCall Seamount

Dive 04 was conducted today on McCall Seamount and was the first dive this cruise in the group of topographic features referred to as the Geologist Seamounts. The dive surveyed the crest of a sharp ridge that extended north of the seamount at a depth of 2,700 meters. The ridge crest was covered with loose talus and was almost completely barren of animals, which was unexpected. This type of substrate continued throughout the dive, except for a couple of small ledges consisting primarily of pillow lavas.


 


 

 

 

Precious pink coral in the family Coralliidae (left) and gold coral (Kulamanamana haumeae, right) observed during the transect.

Precious pink coral in the family Coralliidae (left) and gold coral (Kulamanamana haumeae, right) observed during the transect. Click image for credit and larger view.

camera icon Video highlights from Leg 3 Dive 3

 


NOAA Ship Okeanos Explorer
August 30, 2015

Leg 3 Dive 03: Kona Coast

Dive 03 of the expedition was conducted today along a 450-meter contour at the southern end of the Kona Coast of the Big Island of Hawaiʻi with the objective of surveying a lava flow of a known age (1,868 million years) to see what coral community had grown in the years since the flow had formed. The ROV conducted a 2,000-meter transect during the dive, occasionally zooming in on corals to verify their taxa or type, and using the ROV’s laser scale to estimate the size frequency of the coral colonies encountered on the transect. Colonies of Hemicorallium sp, Kulamanamana haumeaae, Antipatharians, and other coral were visually verified during the transect.


 


 

 

 

Hoplostethus crassispinus - in the same genus as, and related to the Orange Roughy. Unlike the Orange Roughy, this fish lives a somewhat solitary existence, whereas the Orange Roughy schools – which has contributed to the species’ being overfished in some places. There is a general sense that these fish have a level of curiosity because they often retreat into holes when imaged, but then turn around to investigate the investigator.

Hoplostethus crassispinus - in the same genus as, and related to the Orange Roughy. Unlike the Orange Roughy, this fish lives a somewhat solitary existence, whereas the Orange Roughy schools – which has contributed to the species’ being overfished in some places. There is a general sense that these fish have a level of curiosity because they often retreat into holes when imaged, but then turn around to investigate the investigator. Click image for credit and larger view.

camera icon Video highlights from Leg 3 Dive 2

 


NOAA Ship Okeanos Explorer
August 29, 2015

Leg 3 Dive 02: Keahole

Today's dive was conducted off the Kona Coast of the Big Island of Hawaii at the Keahole precious coral bed. This area is primarily carbonate ledge habitat and much of the dive time was spent working the top edge of the drop off. During the dive, the team recovered an acoustic current meter and three flow meters that were deployed in 2012 to collect data on the environmental conditions surrounding these deep-sea coral communities. We also investigated nearby previously marked coral colonies and conducted close-up imaging for comparison to photographs taken over three years ago.


 


 

 

 

Chief Bosun Jerrod Hozendorf watches as ROV Deep Discoverer (D2) is deployed from the aft deck of NOAA Ship Okeanos Explorer. D2’s powerful lighting, high definition camera and newly installed sample collection equipment (drawers, boxes, an advanced manipulator, and positionable illumination system) are visible.

Chief Bosun Jerrod Hozendorf watches as ROV Deep Discoverer (D2) is deployed from the aft deck of NOAA Ship Okeanos Explorer. D2’s powerful lighting, high-definition camera, and newly installed sample collection equipment (drawers, boxes, an advanced manipulator, and positionable illumination system) are visible. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
August 28, 2015

Leg 3 Commences!

NOAA Ship Okeanos Explorer departed Pearl Harbor, Oahu, this morning to commence Leg 3 of the Hohonu Moana expedition. This cruise leg is supported by NOAA’s Deep Sea Coral Research and Technology Program and will focus on recovering instruments and examining known sites offshore of Oahu and the Big Island and exploring unknown seamounts in the Geologists Seamounts group. The first dive was planned for this afternoon at Makapuu, located about six nautical miles off the easternmost point of Oahu. After deploying the ROV today, a problem was discovered with the hanging block and the vehicles were quickly recovered. The team spent the afternoon troubleshooting the block, and the dive was cancelled. Mapping transit operations commenced in the evening and the ship is currently en route to Keahole off the west coast of the Big Island for Dive 02 of the expedition, planned for tomorrow morning.


 


 

 

 

NOAA Ship Okeanos Explorer returned to port at Ford Island, Pearl Harbor this evening, bringing Leg 2 of the Hohonu Moana: Exploring Deep Waters off Hawai’i Expedition to a close. The next leg of the expedition starts August 28, 2015.

NOAA Ship Okeanos Explorer returned to port at Ford Island, Pearl Harbor, this evening, bringing Leg 2 of the Hohonu Moana: Exploring Deep Waters off Hawaiʻi Expedition to a close. The next leg of the expedition starts August 28, 2015. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
August 23, 2015

Arrival in Pearl Harbor

Transit mapping continued today until the ship reached the Pearl Harbor sea buoy, at which time sonars were turned off and Okeanos Explorer made her way into port. By 6:30 pm HST, the ship was moored at the pier on Ford Island and Leg 2 of the expedition was brought to a close. The team onboard spent the day finalizing documentation and reports, debriefing the cruise, and preparing for the in-port period before the next cruise. Although some members of this cruise are headed home, most of the team on board will return to the ship in a week and sail on Leg 3 of the expedition, which departs on Friday, August 28. Come back then to continue exploring with us!


 


 

 

 

The aft deck of NOAA Ship Okeanos Explorer while transiting back to Pearl Harbor, Oahu. The onboard team spent the day catching up on paperwork, finalizing cruise documentation and working on end of cruise demobilization.

The aft deck of NOAA Ship Okeanos Explorer while transiting back to Pearl Harbor, Oahu. The onboard team spent the day catching up on paperwork, finalizing cruise documentation, and working on end-of-cruise demobilization. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
August 22, 2015

Transiting Home

Twenty-four-hour transit mapping was conducted today as Okeanos Explorer continued transiting back to Pearl Harbor, Oahu. A slight course deviation was made to map a portion of an uncharted seamount located within the boundaries of the Papahānaumokuākea Marine National Monument. The onboard team spent the day catching up on paperwork, finalizing cruise documentation, and working on end-of-cruise demobilization.


 


 

 

 

Okeanos Explorer’s Fast Rescue Boat returns to the ship with the four Monk Seal researchers safely onboard.

Okeanos Explorer’s Fast Rescue Boat returns to the ship with the four Monk Seal researchers safely onboard. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
August 21, 2015

NOAA Ship Okeanos Explorer is Called to Service

Late last night, the Commanding Officer received a call from higher levels in the command: the ship needed to divert course from her current transit to Middle Bank and return to Pearl Harbor the following day, and instead transit west to Tern Island, French Frigate Shoals, to rescue four scientists conducting research for NOAA’s Hawaiian Monk Seal Research Program. These researchers are located on one of several camps in the Northwest Hawaiian Islands in the vicinity of the predicted route of Tropical Storm Kilo, which was forecasted to turn into a hurricane. Tropical Storm Loke continues to develop to the west, coming in behind Kilo. These scientists were ordered to evacuate and, as the closest ship despite being a full day’s transit away, NOAA Ship Okeanos Explorer was called to service. The final ROV dive of the cruise was cancelled last night, and the ship turned around and headed for Tern Island where it arrived today around 5:00 pm. One of the ship's Fast Rescue Boats was sent to shore to retrieve the four scientists and some of their gear. By 7:00 pm, everyone was safely on board and Okeanos Explorer was en route back to Pearl Harbor. We have another one to two days of transit and expect to pull into port in Pearl Harbor late Sunday night or Monday morning.


 


 

 

 

Large Styela sp tunicates interspersed with smaller yellow stoloniferous tunicates seen throughout most of the dive.

Large Styela sp tunicates interspersed with smaller yellow stoloniferous tunicates seen throughout most of the dive. Click image for credit and larger view.

camera icon Video highlights from Dive 18

 


NOAA Ship Okeanos Explorer
August 20, 2015

Dive 18: West Nihoa

Dive 18 was conducted today at a channel between Westpac Bank and Nihoa Island, which creates a constriction point for current flow. The objective of the dive was to survey a completely unexplored area for corals and sponges, gathering information on whether high-density communities can be found in areas were the surrounding topography accelerates current flow. The dive started at 1,597 meters on an unsedimented, sloped, and heavily manganese-crusted surface consisting of pillows, boulders, and rubble. The substrate did not contain any sediment and was covered with high densities of large tunicates (Styela sp) as well as smaller unidentified stoloniferous tunicates. As the ROV moved up the slope of the ridge, the substrate continued to be covered with high densities of tunicates, which contained occasional pockets of debris consisting of barnacle plates. Several stalked sponges, live large sessile barnacles (Chirona sp), and chrysogorgid and primnoid corals were also observed, but only one bamboo coral. At 1,530 meters, there was a sudden increase in the density of chrysogorgid corals. As the ROV continued moving up the slope, it encountered very strong currents that impeded forward movement. As a result, the dive was aborted prematurely without reaching the planned endpoint. The ROV left the bottom at a depth of 1,515 meters after having covered a linear distance of 280 meters.


 


 

 

 

An ocean sunset is seen in the reflection of the port windows on the Bridge of NOAA Ship Okeanos Explorer. Inside the Bridge, ENS Chris Licitra examines the ship’s radar for contacts.

An ocean sunset is seen in the reflection of the port windows on the Bridge of NOAA Ship Okeanos Explorer. Inside the Bridge, ENS Chris Licitra examines the ship’s radar for contacts. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
August 19, 2015

Transit Mapping to West Nihoa

Today was a transit day as the ship continued a transit more than 330 nautical miles to the south-eastern section of Papahānaumokuākea Marine National Monument where a dive will be conducted tomorrow on a seamount to the east of Necker Island. Whenever NOAA Ship Okeanos Explorer is underway, the ship is nearly always collecting data of unknown and poorly known areas. Seafloor and water column data were collected during today’s transit with the ship’s EM302 multibeam sonar, EK60 single beam fisheries sonar, and Knudsen 3260 subbottom profiler. Our transit lines were planned to collect mapping data that adds or fills in “holidays” or holes to existing mapping coverage in the region. While the mapping team was busy with data acquisition and processing, other onboard personnel used the transit day to catch up on reports, make adjustments to the ROV, and plan for the next cruise leg of the expedition.


 


 

 

 

A squid, Walvisteuthis youngorum, is imaged at 900m during today’s mid-water transects off Northeast Gardner Pinnacles in the Northwest Hawaiian Islands.

A squid, Walvisteuthis youngorum, is imaged at 900 meters during today’s mid-water transects off Northeast Gardner Pinnacles in the Northwestern Hawaiian Islands. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
August 18, 2015

Dive 17: East North Gardner

Dive 17 was conducted just outside the boundaries of the Monument on a ridge that extends north of Gardner Pinnacles to survey a completely unexplored area for corals and sponges. In addition to surveying the seafloor, this dive also included the second mid-water transects of the expedition, exploring depths between 800-1,200 meters in order to examine the potential prey field for deep-diving toothed whales, as well as documenting other nekton and gelatinous megaplankton. The dive started at 2,065 meters on a wall consisting of manganese-crusted dike rock and rubble, with a sediment-free substrate overgrown by several fan-shaped bamboo corals. As the ROV moved up the flank of the ridge, the density of animals increased and included fan-shaped and unbranched corals. The substrate consisted of manganese-crusted pillows and rubble, which were free of sediment. Once the ROV reached the crest of the ridge, the substrate changed to hardpan, which was overgrown by fan-shaped and unbranched corals, mushroom corals and sponges. As the ROV moved northeastward along the crest of the ridge, it passed through several patches where the substrate consisted of smaller cobble, and there was a concomitant decrease in the density of animals. The ROV moved over to the northern end of the ridge and surveyed down the flank of the ridge, where the density of animals was moderate. The ROV then moved up towards the summit of the cone, before leaving the bottom at a depth of 1,980 meters after covering a linear distance of 890 meters. The ROV then ascended to 1,200 meters to commence the mid-water portion of the dive. Transects were conducted for 10 minutes each at 1,200 meters, 1,100 meters, 1,000 meters, 900 meters, 800 meters, and 550 meters, the latter being where the EK60 sonar showed the densest backscatter layer. A few animals were observed during the mid-water transects, including jellyfishes, ctenophores, siphonophores, shrimps, copepods, fishes, and a squid.


 


 

 

 

A squat lobster perching on a undescribed genus of bamboo coral (family Isididae). This new genus of coral was first discovered in 2007 off of Twin Banks in the Northwest Hawaiian Islands/ Papahānaumokuākea Marine National Monument.

A squat lobster perching on a undescribed genus of bamboo coral (family Isididae). This new genus of coral was first discovered in 2007 off of Twin Banks in the Northwest Hawaiian Islands/Papahānaumokuākea Marine National Monument. Click image for credit and larger view.

camera icon Video highlights from Dive 16

 


NOAA Ship Okeanos Explorer
August 17, 2015

Dive 16: Gardner Terrace

Dive 16 was conducted today on what is believed to be an old reef terrace edge north of Gardner Pinnacles. The objective of this dive was to survey the terrace edge, which is now a 200-meter high narrow ridge, for corals and sponges to gather information on whether high-density communities can be found on ridge topography. The dive started at 1,560 meters on a flat surface consisting of manganese-crusted pavement with pockets of sediment and no animals at the landing site. As the ROV moved northwestward towards the base of the ridge, several fishes were observed, as well as a low number of sponges and unbranched bamboo corals. The density of animals remained low on the flank of the ridge and included sponges, corals, and anemones. Once the ROV arrived on the crest of the ridge, there was a higher sediment cover, as well as a higher density of sponges, which were all oriented with their surfaces perpendicular to the ridge. As the ROV moved northeastward along the crest of the ridge, the community was dominated by a single species of sponge and occasional tripod fishes. Towards the end of the dive, the ROV came upon very large boulders, which were 20 meters in height, and contained a higher density of sponges and corals. The ROV left the bottom at a depth of 1,412 meters after covering a linear distance of 1,150 meters.


 


 

 

 

NOAA’s Seirios camera sled images the ROV Deep Discoverer (D2) as it illuminates a ledge covered with a diverse assemblage of deep-sea corals and sponges. D2 displays its newly installed sample collection equipment – drawers, boxes, an advanced manipulator, and positionable illumination system – that have allowed us to do precision collections under direction of our science team leads.

NOAA’s Seirios camera sled images the ROV Deep Discoverer (D2) as it illuminates a ledge covered with a diverse assemblage of deep-sea corals and sponges. D2 displays its newly installed sample collection equipment – drawers, boxes, an advanced manipulator, and positionable illumination system – that have allowed us to do precision collections under direction of our science team leads. Click image for credit and larger view.

camera icon Video highlights from Dive 15

 


NOAA Ship Okeanos Explorer
August 16, 2015

Dive 15: North Maro Ridge

Dive 15 of the expedition was conducted today on a ridge located north of Maro Reef to survey a completely unexplored area for corals and sponges, providing more information on whether high-density communities can be found on ridge topography and that the orientation of the ridge is important. The dive started at 1,750 meters on a sloped surface consisting of manganese-crusted cobble, rubble, and boulders overlaying sediment, with several nearby chrygorgid coral colonies. As the ROV moved up the flank of the ridge, there was a modest density of corals, which mostly consisted of the species Metallogorgia melanotrichos. Once the ROV arrived at the crest of the ridge, the community changed to one dominated by the coral Pleurocorallium kishinouyei and a yellow species of unstalked crinoids. As the ROV moved east on the crest of the ridge, it passed over several large boulders which were covered with a high density of Iridogorgia bella coral and black corals. The ROV left the bottom at a depth of 1,555 meters after having covered a linear distance of 960 meters.


 


 

 

 

Deep sea corals and sponges provide habitat and refuge for many other animals living on or near the seafloor. Here, a sponge covered with hundreds to thousands of tiny anemones also provides a home to several brittlestars (pink), crinoids or “sea lilies” (yellow) and a basket star (brown).

Deep-sea corals and sponges provide habitat and refuge for many other animals living on or near the seafloor. Here, a sponge covered with hundreds to thousands of tiny anemones also provides a home to several brittlestars (pink), crinoids or “sea lilies” (yellow), and a basket star (brown). Click image for credit and larger view.

camera icon Video highlights from Dive 14

 


NOAA Ship Okeanos Explorer
August 15, 2015

Dive 14: North Pioneer Ridge

Dive 14 was conducted today on a ridge that extends northward from Pioneer Bank to determine whether ridge topography is suitable habitat for high-density communities of corals and sponges. The depth of this dive was closer to the oxygen minimum zone, so we were also interested in detecting any effects of a lower oxygen environment on the communities. The dive started at 1,644 meters on a sloped surface consisting of manganese-crusted cobble and boulders overlaying sediment with a relatively low density of animals, but diverse assemblage of corals and sponges. As the ROV transited towards the flank of the ridge, the density of animals increased and the assemblage was dominated by the sponge Walteria cf. leuckarti and chrysogorgid corals (both Chrysogorgia sp. and Iridogorgia sp.). These groups remained dominant as the ROV moved along the crest of the ridge for the remainder of the dive. As the ROV continued moving along the crest of the ridge, it became evident that the corals and sponges were aggregated along the crest and upper flanks of the ridge. The ROV left the bottom at a depth of 1,535 meters after a total bottom time of more than six hours.


 


 

 

 

Composite image showing the original Sandwell & Smith satellite derived bathymetry data at the bottom, with the Okeanos Explorer EM302 multibeam bathymetry transit data further revealing this unnamed seamount overlain on top. The middle image is a top-down view of the bathymetry data showing the seamount, and the graph in the upper left corner shows the vertical profile of the seamount’s height relative to the seafloor. The map on the upper right shows the bathymetry of the Hawaiian Archipelago with the Papahanoumokuakea Marine National Monument boundary in white, and the location of the seamount circled in red.

Composite image showing the original Sandwell & Smith satellite-derived bathymetry data at the bottom, with the Okeanos Explorer EM302 multibeam bathymetry transit data further revealing this unnamed seamount overlain on top. The middle image is a top-down view of the bathymetry data showing the seamount, and the graph in the upper left corner shows the vertical profile of the seamount’s height relative to the seafloor. The map on the upper right shows the bathymetry of the Hawaiian Archipelago with the Papahānaumokuākea Marine National Monument boundary in white, and the location of the seamount circled in red. Click image for credit and larger view.

camera icon Video highlights from Dive 13

 


NOAA Ship Okeanos Explorer
August 14, 2015

Dive 13: East Pearl & Hermes

Dive 13 was conducted today on a ridge that extends to the southeast of an unnamed seamount east of Pearl and Hermes Atoll, to explore for high-density communities of deep-sea corals and sponges. The dive started at 2,305 meters close to the edge of the ridge on a substrate of heavily manganese-crusted and broken pillow lava that was covered with mostly planar bamboo corals (genus Keratoisis sp) and a few Chrysogorgia sp, and mushroom corals (Anthomastus sp). As the ROV moved up along the crest of the ridge, it became evident that the bamboo corals were all densely aggregated on the narrow ridge crest, oriented perpendicular to the current which was moving across the ridge. As the ROV continued moving upwards along the crest of the ridge, it passed through a couple of patches where the substrate consisted of cobble and did not contain any animals. The ROV left the bottom at a depth of 2,118 meters after covering a linear distance of 700 meters.

After the ROV dive, exploration mapping operations were conducted as usual during transit to the next ROV dive site. Along the way, an uncharted seamount rising approximately 2,818 meters or 8,800 feet (More than one and a third times taller than Mount Washington!) from the seafloor was mapped within the Monument boundary. The feature is 14.8 kilometers wide across the northwest-southeast axis, pyramidal or conical in shape with a sharply defined peak and no long ridge features present. The seamount previously appeared in satellite-derived bathymetry, but was inaccurately represented in terms of height.


 


 

 

 

Purple Ctenophore, possible Leucocia sp., imaged at 1,000 meters during today’s water column transects. Not all ctenophores are pelagic – some are benthic, living near the seafloor.

Purple ctenophore, possibly Lampocteis cruentiventer, imaged at 1,000 meters during today’s water column transects. Not all ctenophores are pelagic – some are benthic, living near the seafloor. Click image for credit and larger view.

camera icon Video highlights from Dive 12

 


NOAA Ship Okeanos Explorer
August 13, 2015

Dive 12: Southeast Pearl & Hermes Ridge

Dive 12 of the expedition was conducted today along the western edge of a rift zone ridge extending southeast from Pearl & Hermes Atoll. The objectives of the dive were to explore for high-density communities of deep-sea corals and sponges along the edge of the ridge crest, to obtain information on the lower depth range of these communities, and to document nekton and gelatinous megaplankton in the water column during the ascent to the surface. The dive started close to a wall with manganese-crusted pillow basalts and several stalked sponges at 2,790 meters. As the ROV moved towards the edge of the wall, there was a small aggregation of stalked sponges and corals. The ROV then moved along the edge of the wall towards the northwest, where the pillow basalts became distinctly round and covered with a high density of barnacles. As the ROV continued moving along the edge of the wall, several narrow canyons, one to two meters in width, were observed. The ROV left the bottom at a depth of 2,773 meters and proceeded to 1,200 meters to conduct the first mid-water transects of the expedition. Mid-water transects were conducted for 10 minutes each at 1,200 meters, 1,000 meters, 800 meters, 600 meters and 450 meters. A few animals were observed during the mid-water transects, including jellyfishes, ctenophores, siphonophores, shrimps, fishes, salps, and a squid.


 


 

 

 

Close up image of a Hexactinellid or glass sponge, with commensal anemones growing throughout its tissues.

Close up image of a Hexactinellid or glass sponge, with commensal anemones growing throughout its tissues. Click image for credit and larger view.

camera icon Video highlights from Dive 11

 


NOAA Ship Okeanos Explorer
August 12, 2015

Dive 11: Bank 9 North

Dive 11 was conducted today on a modest ridge that extends north from the northern half of Bank 9 to explore for high-density communities of deep-sea corals and sponges along the ridge. The dive started at 2,147 meters, very close to the western drop-off of the ridge on a substrate of well defined, manganese-crusted pillows, which were covered with a low density of sponges and corals. As the ROV surveyed up the slope of the ridge, there were several patches that were dominated by sponges, others by stylasterid corals, and still others by bamboo corals. As we continued the survey, the ROV encountered an enormous, unidentified sponge that was over 3.5 meters long and 2.5 meters high. Towards the end of the dive, the ROV moved towards the east side of the ridge, where there was a marked increase in the density of corals and sponges close to the edge of the cliff. The ROV left the bottom at a depth of 2,100 meters after covering a linear distance of 650 meters.


 


 

 

 

Sea star clinging to a coral.

Underside of a sea star feeding on a bamboo coral. Sea stars are predators of invertebrates and feed by inverting their guts on their prey. Click image for credit and larger view.

camera icon Video highlights from Dive 10

 


NOAA Ship Okeanos Explorer
August 11, 2015

Dive 10: Salmon Bank Southeast Ridge

Dive 10 of the expedition was conducted today on a ridge that extends to the southeast of Salmon Bank, with the objective of surveying a completely unexplored area for corals and sponges. The dive started at 2,052 meters on a manganese-crusted, sloped surface covered with rubble and sediment and a moderate density of sponges and corals. As the ROV moved up the slope of the ridge, the density of animals increased substantially around at 2,000 meters, including numerous sponges and corals. The ROV kept moving up the slope following a narrow region along the ridge, which had a higher density of animals. At 1,882 meters, there was another evident increase in the density of animals, coinciding with the ROV moving over to the western side of the ridge. The ROV left the bottom at a depth of 1,849 meters after covering a linear distance of approximately 550 meters. Several fishes were observed during the dive.


 


 

 

 

A very large spectacular stalked sponge (Caulophacus sp.) encountered during the dive.

A very large spectacular stalked sponge (Caulophacus sp.) encountered during the dive. Click image for credit and larger view.

camera icon Video highlights from Dive 9

 


NOAA Ship Okeanos Explorer
August 10, 2015

Dive 09: East Salmon Bank

Today’s dive was located on a sharp ridge that extended west from East Salmon Bank, and its objective was to survey for the presence of high densities of corals and sponges and examine the impact of ridge orientation on the presence of high-density communities. The dive started at 2,282 meters on a manganese-crusted, sloped surface covered with boulders and rubble with a moderate density of sponges and corals. As the ROV moved up the slope, the density of animals remained moderate and included sponges, corals, and asteroids. Further up the ridge, the ROV passed by a region of well-preserved pillow flows at 2,206 meters, which had a higher density of corals and sponges growing on them. The ROV left the bottom at a depth of 2,103 meters after a total bottom time of five hours and 50 minutes, having covered a linear distance of 730 meters.


 


 

 

 

Large stalked sponge (Bolosoma sp.) providing a home for a myriad of brittlestars and crustacean associates.

Large stalked sponge (Bolosoma sp.) providing a home for a myriad of brittlestars and crustacean associates. Click image for credit and larger view.

camera icon Video highlights from Dive 8

 


NOAA Ship Okeanos Explorer
August 9, 2015

Dive 08: Bank 9 South

Dive 08 of the expedition was conducted today on a seamount on the south side of Bank 9, located about 50 nautical miles south of Pearl and Hermes Atoll. Previous high-resolution mapping data of Bank 9 suggests that it is a composite feature that includes both a Cretaceous guyot (flat-topped seamount) to the south as well as a younger Hawaiian guyot to the north. The objectives of the dive were to explore for high-density communities of deep-sea corals and sponges and look for clues on how this peculiar composite seamount might have formed. The dive started at 1,380 meters on a sloped surface of pavement mixed with rubble, heavily encrusted with manganese (Mn) and hosting a bamboo coral and a chrysogorgid coral. As the ROV moved up the slope towards the terrace of the seamount, the density of animals remained very low and included corals, sponges, asteroids, crinoids, sea pens, urchins, shrimps, fishes, and sea cucumbers. On the terrace of the seamount, the substrate changed to Mn-coated cobbles and the density of animals continued to remain low. As the ROV reached and moved up the slope of the cone, several colonies of scleractinian corals (Enallopsammia rostrata), bubble gum corals and sponges (Atlantisella sp.) appeared; however, the density of animals remained low. On the summit there were several pillow lavas in parallel rows and very few animals. The ROV left the bottom at a depth of 1,096 meters after a total bottom time of six hours and 52 minutes.


 


 

 

 

ROV Deep Discoverer (D2) places a piece of an uknown Corallium species collected at 2078m depth in one of the bio boxes on the ROV. Following collection, the boxes are sealed and keep specimens insulated for their return to the surface.

ROV Deep Discoverer (D2) places a piece of an uknown Corallium species collected at 2,078 meters depth in one of the bio boxes on the ROV. Following collection, the boxes are sealed to keep specimens insulated for their return to the surface. Click image for credit and larger view.

camera icon Video highlights from Dive 7

 


NOAA Ship Okeanos Explorer
August 8, 2015

Dive 07: Pioneer Bank Ridge

Dive 07 of the expedition was conducted on a sharp ridge extending to the south of Pioneer Bank to survey an unknown area below previous Pisces submersible dives on the ridge in order to determine the lower depth limit of known communities of corals and sponges. The dive started on a ridge crest at about 2,115 meters where the density of animals was immediately high from the start and included numerous bamboo corals, black corals, primnoid corals, and sponges. Unlike yesterday, the dominant bamboo corals were branched and there was an absence of Acanthogorgia, and the community somewhat differs from the community observed further upslope. Large fields of dead organic material that appeared to be barnacle plates were seen on several locations. As the ROV moved up the crest of the ridge, the density of animals increased and included numerous gorgonians, black corals, and sponges. The ROV left the bottom at a depth of 2,000 meters after the team determined that the dense community seen by the previous submersible dives further upslope extended at least six kilometers down the ridge to where today’s dive was conducted. This is clearly an important large, high-density community of corals and sponges.


 


 

 

 

Deep sea fish in the family Macrouridae, possibly in the genus Malacocephalus or Trachonurus, with an isopod parasite. Photographed at 1814m.

Deep-sea fish in the family Macrouridae, possibly in the genus Malacocephalus or Trachonurus, with an isopod parasite. Imaged at 1,814 meters. Click image for credit and larger view.

camera icon Video highlights from Dive 6

 


NOAA Ship Okeanos Explorer
August 7, 2015

Dive 06: West Northampton Seamount Ridge

Dive 06 of the expedition was located on a ridge extending south from West Northampton Seamount. The objective of the dive was to survey a completely unexplored area of the seamount, testing the hypothesis that high-density communities of corals and sponges can be found on ridge topography. The dive started on a slope at 1,986 meters with several animals present close to the landing spot, including sponges, black corals, crinoids, and fish. As the ROV moved westward up the side of the ridge, the number of animals seen increased and included unbranched bamboo corals, black corals, sponges, chrysogorgid corals, and fish. As the ROV continued to move up the slope, the density of animals continued to increase and included numerous gorgonians, sponges, black corals, and sea pens. As the ROV reached the ridge crest, a very high-density community was encountered that included many corals and sponges, as well as several crabs, shrimps, and fish. This community continued through the remainder of the dive as the ROV surveyed up along the crest. The ROV left the bottom at a depth of 1,782 meters after covering a linear distance of 950 meters.


 


 

 

 

ROV Deep Discoverer places an unidentified sponge in the vehicle's sampling drawer.

ROV Deep Discoverer places an unidentified sponge in the vehicle's sampling drawer. Click image for credit and larger view.

camera icon Video highlights from Dive 5

 


NOAA Ship Okeanos Explorer
August 6, 2015

Dive 05: Southeast Maro Ridge

Dive 05 of the expedition was conducted today on a ridge that is southeast of Maro Reef. This dive was the deepest conducted during this cruise and its objective was to explore biological communities at depths that have never previously been explored inside Papahānaumokuākea Marine National Monument. The dive started on flat, lightly sedimented pavement at 4,829 meters. As the ROV moved westward towards the base of the ridge, a few animals were seen that included sea stars, sponges, a swimming cucumber, a shrimp, and an ophidiid fish, as well as a plastic cup. At the base of the wall, the substrate changed to pillow lava flows that were lightly covered with sediment.  Many of these pillows were small, suggesting they came from a source close by. As the ROV moved up the slope, the density of animals remained very low, and included sea stars, sponges, polychaete worms, shrimps, an anemone, a hydroid, a stalked crinoid overgrown by hydroids, and an ophidiid fish. The ROV left the bottom after a total bottom time of two hours and 49 minutes, having covered a linear distance of 280 meters.


 


 

 

 

Bathymetric image of a crater located on the eastern Ridge off Maro Reef. The crater is 6km (3.1nm) across and over 3km deep, with walls up to 800m high. Sonar and sample data collected this cruise may provide insights into the currently unknown origin of the crater.

Bathymetric image of a crater located on the eastern Ridge off Maro Reef. The crater is six kilometers (3.1 nautical miles) across and over three kilometers deep, with walls up to 800 meters high. Sonar and sample data collected during this cruise may provide insights into the currently unknown origin of the crater. Click image for credit and larger view.

camera icon Video highlights from Dive 4

 


NOAA Ship Okeanos Explorer
August 5, 2015

Dive 04: Maro Crater

Dive 04 of the expedition was the deepest yet, starting 3,035 meters deep on the eastern ridge of a crater that is located east of Maro Reef. The dive objectives were to explore for high-density communities of deep-sea corals and sponges along the ridge of the crater, as well as gain insights into how this peculiar feature might have formed geologically. The dive started on flat, manganese-coated pavement at 3,035 meters with few animals including sea cucumbers, stalked sponges, and an unbranched bamboo coral. As the ROV moved towards the base of the wall, a field of manganese nodules (two to five centimeters in diameter) was seen on a flat surface, and the density of animals remained very low. Large boulders were present at the base of the wall. As the ROV moved up the wall of the crater, the substrate changed to pillow lavas that occasionally had animals on them, including stalked crinoids, ophiuroids, tube worms, and bamboo corals. At 2,800 meters, the density of animals slightly increased and several stalked sponges, black corals, bamboo corals, and sea cucumbers were seen. The density of animals remained low as the ROV made its way over the crest of the ridge, mostly including stalked crinoids and sponges, and remained low as the ROV moved towards the outer edge of the ridge and moved down the outer edge of the crater. Few fishes were observed during this dive and included eels and rattails.


 


 

 

 

A corallium that is nearly completely overgrown by zooanthid (another type of cnidarian), and a brittlestar living in association. This particular species or coral is not commercially harvested, but is in the precious coral group that is often commercially harvested for jewelry at shallower depths.

A corallium that is nearly completely overgrown by zooanthid (another type of cnidarian) and a brittlestar living in association. This particular species of coral is not commercially harvested, but is in the precious coral group that is often commercially harvested for jewelry at shallower depths. Click image for credit and larger view.

camera icon Video highlights from Dive 3

 


NOAA Ship Okeanos Explorer
August 4, 2015

Dive 03: St. Rogatien Rift

Today's dive was located on the east side of a large rift zone ridge north of St. Rogatien Bank with the objective of surveying a completely unexplored area, testing the hypothesis that high-density communities of corals and sponges can be found on ridge topography. The dive started on a relatively flat terrace surface close to a steep slope at 2,151 meters. The surface was covered by a dense aggregation of manganese nodules (two to five centimeters in diameter) that lay loosely on the bottom. Several unbranched corals, sponges, and a stalked crinoid were observed at the landing site and there was no current. A field of manganese crusted boulders was observed upon moving up the slope, which was void of animals. Further up the slope at around 2,100 meters, the density of animals increased somewhat and included corals, sponges, and crinoids. The density of animals remained moderately low until a depth of 2,050 meters, when an increase of corals and sponges was observed. As the ROV moved up the slope, both the density and diversity of animals increased with decreasing depth and distance to the ridge crest, with numerous species of gorgonians, black corals, and sponges being recorded. The ROV was not able to reach the target end point on the top of the ridge at 1,900 meters and had to leave the bottom at 1,958 meters. Only a handful of fishes were observed during the dive.


 


 

 

 

A beautiful primnoid coral with a commensal crinoid (sea lily) and ophiuroid (brittlestar) observed on the dive.

A beautiful primnoid coral with a commensal crinoid (sea lily) and ophiuroid (brittlestar) observed on the dive. Click image for credit and larger view.

camera icon Video highlights from Dive 2

 


NOAA Ship Okeanos Explorer
August 3, 2015

Dive 02: North French Frigate Shoals (Kanehunamoku Seamount)

Today's dive was on Kanehunamoku Seamount north of French Frigate Shoals with the objective of determining the lower depth range of a known dense coral and sponge community found in 2007 during a Pisces submersible dive. The dive started at 2,460 meters on a slope with pillow lava flow formations with some tube formations that were covered with a moderate density of primnoids, isidids, antipatharians (Bathypathes alternata), and sponges. As the ROV moved up the slope, the density of animals remained moderate and was dominated by primnoids, isidids, and black corals, with occasional sponges and crinoids. At 2,240 meters the densities of primnoids, isidids, and sponges became high and remained high through the end of the dive at 2,237 meters. While the ROV did not quite reach the depth of the previous submersible dive conducted in the area (1,700 meters), today's dive observations indicate that a dense coral and sponge community extends down to a depth of approximately 2,250 meters in this area.


 


 

 

 

Two rock samples – likely manganese coated basalt – were collected during today’s dive. Both specimens will be sent to Oregon State University’s Marine Geology Repository where they will be described and made publicly accessible.

Two rock samples – likely manganese coated basalt – were collected during today’s dive. Both specimens will be sent to Oregon State University’s Marine Geology Repository where they will be described and made publicly accessible. Click image for credit and larger view.

camera icon Video highlights from Dive 1

 


NOAA Ship Okeanos Explorer
August 2, 2015

Dive 01: East Necker Seamount (Keoea Seamount)

We conducted our first ROV dive of the expedition today on the southeast rift zone of a seamount east of Necker Island (Mokumanamana). The primary objective of the dive was to determine the lower depth range of a deep-sea coral and sponge community found in 2003 during a Pisces submersible dive. The dive started on a flat terrace 2,220 meters deep and explored a steep slope on the rift zone up to a final target depth just below the previously explored community. The bottom was on a slope with rubble and as the ROV moved upslope, numerous pillow basalts were observed. At these deeper depths, very few animals were observed and included gorgonians (isidids, primnoids), hexactinellid sponges, anemones, black corals, eels, and shrimp. At a depth of 2,050 meters, the density of benthic animals increased substantially, with high densities of isidids, primnoids, sponges, as well as occasional crinoids. While the location of the end of the dive did not quite reach the position of the previous submersible dive conducted in this area (1,720 meters), the high densities of animals observed during today’s dive suggest that a dense coral and sponge community extends until depths of at least 2,050 meters in this area.


 


 

 

 

An unnamed seamount was mapped during our transit mapping operations today. The 2,865-meter high seamount's peak is 562 meters below the surface of the water, with surrounding water depths of 4,709 meters.

An unnamed seamount was mapped during our transit mapping operations today. The 2,865-meter high seamount's peak is 562 meters below the surface of the water, with surrounding water depths of 4,709 meters. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
August 1, 2015

Transit Mapping

Okeanos Explorer continued 24-hour exploration mapping while transiting to the first ROV dive site. The ship mapped an unnamed seamount and a collapsed caldera on the way. The shipboard team conducted safety drills and continued with system familiarization and preparations for the start of dive operations.


 


 

 

 

NOAA Ship Okeanos Explorer in port on Ford Island, in Pearl Harbor, Hawaii.

NOAA Ship Okeanos Explorer in port on Ford Island, in Pearl Harbor, Hawaii. Click image for credit and larger view.

 


NOAA Ship Okeanos Explorer
July 31, 2015

Underway!

NOAA Ship Okeanos Explorer departed Pearl Harbor, Oahu, this morning at approximately 0930 and got underway to commence Leg 2 of the Hohonu Moana: Exploring Deep Waters off Hawaiʻi Expedition. Onboard personnel spent the day preparing, training, and familiarizing personnel with shipboard systems, while many of the shore-based scientists became familiar with telepresence tools and the new University of Hawaii at Manoa Exploration Command Center. Due to Navy weapons testing in the vicinity of our first planned remotely operated vehicle (ROV) dive site and long transit times, the first ROV dive of the expedition has been cancelled and we will instead start with the second planned ROV dive at East Necker, or Keoea, Seamount. The sonar systems were turned on after we departed port, and the ship is currently conducting mapping transit operations en route to the first ROV dive site, planned for August 2. Due to a problem with the satellite connection, we are functioning on reduced bandwidth and as a result will only stream two video feeds to shore during this leg.


 


 

 

 

 

 

(top)

Sign up for the Ocean Explorer Email Update List.

Back to Top