Description: Author Posting. © Oceanography Society, 2007. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 20, 1 (2007): 30-41.

Description: The discovery of hydrothermal vents and the unique, often endemic fauna that inhabit them represents one of the most extraordinary scientific discoveries of the latter twentieth century. Not surprisingly, after just 30 years of study of these remarkable—and extremely remote—systems, advances in understanding the animals and microbial communities living around hydrothermal vents seem to occur with every fresh expedition to the seafloor. On average, two new species are described each month—a rate of discovery that has been sustained over the past 25–30 years. Furthermore, the physical, geological, and geochemical features of each part of the ridge system and its associated hydrothermal-vent structures appear to dictate which novel biological species can live where. Only 10 percent of the ridge system has been explored for hydrothermal activity to date (Baker and German, 2004), yet we find different diversity patterns in that small fraction. While it is well known that species composition varies along discrete segments of the global ridge system, this “biogeographic puzzle” has more pieces missing than pieces in place.

Description: E. Ramirez-Llodra is supported by the ChEss-Census of Marine Life program (A.P. Sloan Foundation), which is kindly acknowledged. C.R. German also acknowledges support from ChEss- Census of Marine Life and further support from the Natural Environment Research Council (UK) and from the US National Science Foundation (NSF) and National Oceanic and Atmospheric Administration (NOAA). T. Shank acknowledges support from NSF, the US National Aeronautic and Space Administration Astrobiology Program, NOAA-Ocean Exploration, and the Deep-Ocean Exploration Institute at the Woods Hole Oceanographic Institution.

Description: Author Posting. © Oceanography Society, 2007. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 20, 4 (2007): 52-61.

Description: Human-occupied submersibles, towed vehicles, and tethered remotely operated vehicles (ROVs) have traditionally been used to study the deep seafloor. In recent years, however, autonomous underwater vehicles (AUVs) have begun to replace these other vehicles for mapping and survey missions. AUVs complement the capabilities of these pre-existing systems, offering superior mapping capabilities, improved logistics, and better utilization of the surface support vessel by allowing other tasks such as submersible operations, ROV work, CTD stations, or multibeam surveys to be performed while the AUV does its work. AUVs are particularly well suited to systematic preplanned surveys using sonars, in situ chemical sensors, and cameras in the rugged deep-sea terrain that has been the focus of numerous scientific expeditions (e.g., those to mid-ocean ridges and ocean margin settings). The Autonomous Benthic Explorer (ABE) is an example of an AUV that has been used for over 20 cruises sponsored by the National Science Foundation (NSF), the National Oceanic and Atmospheric Administration (NOAA) Office of Ocean Exploration (OE), and international and private sources. This paper summarizes NOAA OE-sponsored cruises made to date using ABE.

Description: Author Posting. © Oceanography Society, 2010. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 23, 1 (2010): 212-213.

Description: Seamounts are fascinating natural ocean laboratories that inform us about fundamental planetary and ocean processes, ocean ecology and fisheries, and hazards and metal resources. The more than 100,000 large seamounts are a defining structure of global ocean topography and biogeography, and hundreds of thousands of smaller ones are distributed throughout every ocean on Earth.

Description: Author Posting. © Oceanography Society, 2010. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 23, 1 (2010): 104-105.

Description: One of the longest seamount tracks in the Atlantic Ocean was formed by the Great Meteor or New England hotspot. This more than 3000-km-long hotspot track formed both the New England and Corner Rise seamounts, with a pause in volcanism 83 million years ago as evidenced by the morphological gap between chains.

Description: Author Posting. © Oceanography Society, 2010. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 23, 1 (2010): 108-122.

Description: Seamount systems that are geographically, hydrographically, topographically, and/or genetically “isolated” are likely to have developed highly endemic taxa and ecosystems. Although current estimates of endemism are challenged by inconsistencies in sampling approaches, the physical, biological, and geological processes intrinsic to seamount systems can undeniably serve to connect or isolate populations, stimulate genetic divergence, drive the formation of new species, and structure diversity and endemism. In fact, the large variety of interconnected mechanisms that promote or impede the genetic connectivity of seamount communities via dispersal (and the long-term maintenance of species or the subsequent divergence of populations leading to speciation) are key unknowns to understanding the fundamental evolutionary processes that structure both the diversity and biogeography of deep-sea fauna. Fortunately, the net results of these ecological interactions at seamounts are represented in the patterns of genetic connectivity of the constituent species. The conclusions of the relatively few genetic connectivity studies across seamount fish, coral, and invertebrates are largely inconsistent, reflecting the ecological and evolutionary complexities of seamount systems. Yet, identifying the “connectivity” of seamount populations and their diverse ecosystems, which are increasingly vulnerable to threats from destructive fisheries and mining practices, is vital for developing and evaluating conservation and management strategies for seamount resources. Integrated, multidisciplinary studies of the physical, chemical, geological, an ecological dynamics of seamounts will continue to reveal the value of seamounts as natural laboratories in which to gain insights into the factors that elucidate the role these systems play in the dispersal, evolution, and biodiversity of deep-sea fauna. These studies will also direct the management of seamount biological diversity, which is increasingly susceptible to anthropogenic disturbance.

Description: Support provided by the Office of Ocean Exploration, National Oceanic and Atmospheric Administration (NA05OAR4601054), the National Science Foundation (OCE- 0624627, OCE-0451983, OCE-0647612), the Census of Marine Life for Seamounts (CenSeam) Program through their minigrant program (Grant #12301), and a Fellowship from the Deep Ocean Exploration Institute of the Woods Hole Oceanographic Institution.

Description: Author Posting. © Oceanography Society, 2010. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 23, 1 (2010): 20-21.

Description: The term seamount has been defined many times (e.g., Menard, 1964; Wessel, 2001; Schmidt and Schmincke, 2000; Pitcher et al., 2007; International Hydrographic Organization, 2008; Wessel et al., 2010) but there is no “generally accepted” definition. Instead, most definitions serve the particular needs of a discipline or a specific paper.

Description: Author Posting. © Oceanography Society, 2007. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 20, 1 (2007): 152-161.

Description: Autonomous and remotely operated underwater vehicles play complementary roles in the discovery, exploration, and detailed study of hydrothermal vents. Beginning with clues provided by towed or lowered instruments, autonomous underwater vehicles (AUVs) can localize and make preliminary photographic surveys of vent fields. In addition to finding and photographing such sites, AUVs excel at providing regional context through fine-scale bathymetric and magnetic field mapping. Remotely operated vehicles (ROVs) enable close-up inspection, photomosaicking, and tasks involving manipulation of samples and instruments. Increasingly, ROVs are used to conduct in situ seafloor experiments. ROVs can also be used for fine-scale bathymetric mapping with excellent results, although AUVs are usually more efficient in such tasks.