The Hercules ROV being maintenanced after a dive.

The ROV Hercules receives maintenance after a dive. Click image for larger view.

Mountains in the Sea 2004: Exploring the New England Seamount Chain

May 8-24, 2004

Visiting a seamount is a special event, but returning to a previously visited seamount is exceptional. Second opportunities are rare, because seamount exploration requires costly resources, such as research submarines or remotely operated vehicles (ROVs), and scheduling is tight. So, for these and other reasons, we are excited about returning to the three seamounts we visited last August on Mountains in the Sea 2003.

The first exploration of any undersea site produces many questions and almost no answers.

Last year, we saw that all three seamounts—Manning, Kelvin, and Bear—had spectacular octocoral gardens. We collected octocoral (coral with eight featherlike tentacles) specimens for reproductive condition and genetic analysis, and we found that a diverse array of commensals (organisms that benefit from a harmless relationship with another species) live with these corals. The commensals apparently use the corals for substrate and help in getting food; they may also require the corals to expend small amounts of energy.

Anticipating interesting patterns in coral distribution, we took long video sequences to document the coral abundances up the side and over the top of the seamounts. The video also enabled us to look at other wildlife, such as deep-sea fishes, and to determine whether they use the corals for food or shelter. In another effort, we set out bare blocks of basalt (volcanic rock) to see if we could collect newly settled coral colonies.

This year, the team will continue to video, completing comprehensive transects around several other sides of the seamounts. We aim to document the occurrences of the corals with respect to current flow. We also plan to observe the relationships of the benthic (bottom-dwelling) fishes to coral distributions as well as to other aspects of the seamount landscape. Additionally, we will recover the basalt settlement blocks, determining whether any young corals have settled here in the last 10 months, and sample extensively for population analysis of commensal species. We know from our analysis of last year's images that many coral species remain to be collected and identified. So, this time around, we will dedicate much effort to documenting the octocorals of the seamounts.


Updates & Logs
Click images or links below for detailed mission logs and updates.

May 23 log May 23, 2004 Hercules and Argus make one more trip to the bottom to visit Retriever Seamount. The educators take turns in the Science One chair, learning how to take "frame grabs" whenever the video screen fills with an interesting scene.

May 21 log May 21, 2004 Hercules spends the day roaming Balanus Seamount and capturing spectacular video footage and still images. The diversity on Balanus and the abundance of Corallium coral in one place has never before been seen.

May 19 log May 19, 2004 Hercules dives to nearly 1800 m and works throughout the afternoon, taking video and gathering samples — with no mechanical problems at all.

May 17 log May 17, 2004 Hercules passes its previous depth record. This record was not easily earned.

May 16 log May 16, 2004 A strong Bermuda high allows for an excellent collection of specimens. Learn what happens to these specimens. camera icon View the slide show of images taken on this day.

May 15 log May 15, 2004 Learn how to do the Caprellid Dance. Also, see the unusual coral specimens the science team discovered. camera icon View the slide show of images taken on this day.

May 11 log May 14, 2004 Witness how the science team achieves one of its main objectives by recovering the basalt blocks left behind by DSV Alvin last July. camera icon View the slide show of images taken on this day.

May 12 log May 12, 2004 Researchers find a variety of corals, urchins, sponges, and sea stars on Bear Seamount. Specimens must be processed quickly to ensure their value. camera icon View the slide show of images taken on this day.

May 11 log May 11, 2004 A suite of cameras allows several scientists a side-by-side view. camera icon View the slide show images taken on this day. camera icon Includes video.

May 10 log May 10, 2004 A visit to Bear Seamount, and IFE's ROV Hercules and light-bearing camera sled Argus receive their first workout. camera icon Includes video.

May 8 log May 8, 2004 Check out the array of equipment used to explore this New England Seamount Chain.