75 research outputs found

    Development and evaluation of electromechanical cables for deep sea buoy applications

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    Electromechanical (E/M cables have been developed in order to satisfy the growing need for real time data telemetry from oceanographic moorings. Several E/M cable designs have been implemented with the cooperation of private industry in order to accommodate E/M cable requirements for different mooring experiments. Surface and subsurface E/M cable applications are discussed with reference to WHOI Projects (ESOM, STEM, RTEAM). Floating tether and their special designs (concave up, S-tether) are also illustrated together with an evaluation of their performance at sea (RTEAM, MOIST, TETHERMOOR, ABRUPT TOPOGRAPHY). Data from material tests performed by the OS&M Labratory are reported in seven separate tables.Funding was provided by the Office of Naval Research under Contract No. N00014-84-C-0134

    TOSSIT: a low-cost, hand deployable, rope-less and acoustically silent mooring for underwater passive acoustic monitoring

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    © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Zitterbart, D., Bocconcelli, A., Ochs, M., & Bonnel, J. TOSSIT: a low-cost, hand deployable, rope-less and acoustically silent mooring for underwater passive acoustic monitoring. HardwareX, 11, (2022): e00304, https://doi.org/10.1016/j.ohx.2022.e00304.Passive Acoustic Monitoring (PAM) has been used to study the ocean for decades across several fields to answer biological, geological and meteorological questions such as marine mammal presence, measures of anthropogenic noise in the ocean, and monitoring and prediction of underwater earthquakes and tsunamis. While in previous decades the high cost of acoustic instruments limited its use, miniaturization and microprocessor advances dramatically reduced the cost for passive acoustic monitoring instruments making PAM available for a broad scientific community. Such low-cost devices are often deployed by divers or on mooring lines with a surface buoy, which limit their use to diving depth and coastal regions. Here, we present a low-cost, low self-noise and hand-deployable PAM mooring design, called TOSSIT. It can be used in water as deep as 500 m, and can be deployed and recovered by hand by a single operator (more comfortably with two) in a small boat. The TOSSIT modular mooring system consists of a light and strong non-metallic frame that can fit a variety of sensors including PAM instruments, acoustic releases, additional power packages, environmental parameter sensors. The TOSSIT’s design is rope-less, which removes any risk of entanglement and keeps the self-noise very low.The development of the TOSSIT mooring was supported by a Woods Hole Oceanographic institution Innovative Technology Award (Award number 25226). TOSSIT deployment in Argentina was supported by a Woods Hole Oceanographic Institution Mary Sears visitor award (Award number 24700) and TOSSIT deployments during SBCEX were funded by the Office of Naval Research Task Force Ocean (ONR TFO, Award number: N000141912627). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    ESOM I and II final report

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    An Engineering Surface Oceanographic Mooring (ESOM) program was initiated in 1989 by the Woods Hole Oceanographic Institution for the purpose of evaluating the long term, in situ performance of new moored array materials and sensors. For logistic and practical reasons, a site 12 miles southwest of Bermuda, with a water depth of 3000m was selected to deploy the mooring. Following well established design practice the upper part of the mooring down to a depth of 1900m was made of plastic jacketed, steel armored wire ropes and cables. Groups of test samples were attached at different depths to the main mooring line. The lower part of the mooring was made of compliant, plaited nylon rope. The mooring was deployed in March 1989. It was recovered and reset, with a vertical acoustic telemetry prototype system, in April 1990. The at-sea phase of the program ended in November 1990 when the termination of a test cable failed and the mooring broke loose. The entire mooring was recovered and all of its samples and components were carefully inspected and tested. In addition to the novel acoustic link, mooring components tested included new wire ropes, new electromechanical cables and their terminations, low drag fairings, fishbite resistant jackets, and a new type of surface buoy.Funding was provided by the Office of Naval Research under Contract No. N00014-90-J-1719

    Testing and evaluation of SURLYN foam and SPECTRA fiber ropes for buoy systems applications

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    Funding was provided by the Office of Naval Research through contract Number N00014-84-C-0134

    In situ measurements of the dynamics of a full scale bottom moored mine model

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    Under the sponsorship of the Naval Surface Warfare Center (NSWC), Dalgren Division, White Oak, Marland, the Ocean Systems & Mooring Laboratory of the Woods Hole Oceanographic Institution devised (1991) and conducted (1992) an experiment to measure the dynamic response of a full scale model of the CAPTOR mine, submerged and moored in strong tidal currents near Woods Hole, MA. Specifically, the purpose of this sophisticated engineering experiment was to obtain long term, high frequency measurements of the spatial position of the CAPTOR body, of the tension at both ends of the mooring line, and of the mooring line strumming, as a function of the currents prevailing at the site. This report first describes the main components and the method of deployment of the complex CAPTOR Dynamics Experiment (CAPTORDYN) set up. It then presents the mechanical and electrical designs of the entire system. Finally a review of the results obtained concludes the report.Funding was provided by the Naval Surface Warfare Center under Contract No. N60921-91-C-0216

    A preliminary investigation into the ecology and behavior of blue whales (Balaenoptera musculus) in the Gulf of Corcovado, Chile

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    A joint effort between WHOI and the Melimoyu Ecosystem Research Institute (MERI) sought to gain a better understanding of a population of blue whales (Balaenoptera musculus) in the Gulf of Corcovado, Chile. A cruise in March 2014 resulted in the deployment of 5 DTAGs, which are miniature sound and orientation recording tags that are attached via suction cups. A total of five tag deployments on four individual whales were achieved, totaling 21 hr 11 min. Dives were predominantly between 10 and 50 m in depth, with a maximum of 139 m. Sloughed skin found on the suction cups of recovered tags and fecal samples were preserved to be used for genetic, dietary and pollutant analyses. Acoustic data on the tags revealed numerous calls from distant blue whales, and an apparent call exchange was recorded between a tagged juvenile whale and a distant animal. Photo-identification images and acoustic recordings of all marine mammal species encountered were obtained whenever possible; these included humpback whales (Megaptera novaeangliae), Peale’s dolphins (Lagenorhynchus australis), Chilean dolphins (Cephalorhynchus eutropia), and bottlenose dolphins (Tursiops truncatus). Continuation of this collaboration has great potential to provide information to policy makers regarding how to protect the unique habitats in this region.Funding was provided by the Melimoyu Ecosystem Research Institut

    Photoidentification catalog of Cuvier's beaked whale (Ziphius cavirostris) in the Ligurian Sea

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    A photo-ID catalog of Cuvier's beaked whales was compiled by analyzing data collected in the Ligurian Sea from 1998 to 2007. Data were collected during dedicated surveys for beaked whales, opportunistic whale watching cruises, and during several tagging efforts. A total of 2,300 photographs was collected and referenced to time and GPS position. Of these photographs, 650 were of sufficient quality to use for photo-identification. Photographs were divided into four categories, based on scarring and pigmentation patterns: very distinctive (heavily scarred and/or bold pigmentation), distinctive (many distinct scars and/or bold pigmentation), slightly distinctive (few scars and lack of bold pigmentation), and not distinctive (no scars and solid brown animal). 127 individual whales were identified, of which 10 were classified as adult males, 3 as adult females, 3 as calves, and 27 as immature whales, based on the above criteria. An additional 26 whales were classified as possible males, and 28 as possible females. During the 9 year study period, 34 whales were resighted, and the longest time between resights was 7 years

    First observed wild birth and acoustic record of a possible infanticide attempt on a common bottlenose dolphin (Tursiops truncatus)

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    Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Society for Marine Mammalogy for personal use, not for redistribution. The definitive version was published in Marine Mammal Science 32 (2016): 376–385, doi:10.1111/mms.12248.We observed the birth of a common bottlenose dolphin (Tursiops truncatus) followed immediately by a possible infanticide attempt in the estuary near Savannah, Georgia. Our report is unique in several ways: first, we witnessed the birth of the calf; second, we observed infanticidal behavior almost immediately afterward; and third, we obtained acoustic recordings concurrent with the possible infanticidal behavior. Our observations provide insight into aggressive, possible infanticidal, behavior in bottlenose dolphins.Boat time and support was provided by Department of Education/Title VII Award P382G090003. Additional support was provided by EDGE (Enhancing Diversity in Geosciences Education through Costal Research in Port City) NSF award GEO-0194680.2016-07-1

    Natural dimethyl sulfide gradients would lead marine predators to higher prey biomass

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    © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Owen, K., Saeki, K., Warren, J. D., Bocconcelli, A., Wiley, D. N., Ohira, S., Bombosch, A., Toda, K., & Zitterbart, D. P. Natural dimethyl sulfide gradients would lead marine predators to higher prey biomass. Communications Biology, 4(1), (2021): 149, https://doi.org/10.1038/s42003-021-01668-3.Finding prey is essential to survival, with marine predators hypothesised to track chemicals such as dimethyl sulfide (DMS) while foraging. Many predators are attracted to artificially released DMS, and laboratory experiments have shown that zooplankton grazing on phytoplankton accelerates DMS release. However, whether natural DMS concentrations are useful for predators and correlated to areas of high prey biomass remains a fundamental knowledge gap. Here, we used concurrent hydroacoustic surveys and in situ DMS measurements to present evidence that zooplankton biomass is spatially correlated to natural DMS concentration in air and seawater. Using agent simulations, we also show that following gradients of DMS would lead zooplankton predators to areas of higher prey biomass than swimming randomly. Further understanding of the conditions and scales over which these gradients occur, and how they are used by predators, is essential to predicting the impact of future changes in the ocean on predator foraging success.Open Access funding enabled and organized by Projekt DEAL. This study was funded by the Herrington Fitch Family Foundation, by the Woods Hole Oceanographic Institution Joint Initiative Awards Fund from the Andrew W. Mellon Foundation and The President’s Investment Fund, and by KAKENHI, Grants-in-Aid for Basic Research (B) (Grant no. 16H04168) and Bilateral Programs Joint Research Projects (open partnership), both from the Japan Society for the Promotion of Science. The authors thank Mrs. Norio Hayashi, Takanori Nagahata, and Ms. Mihoko Asano (Mitsubishi Chemical Analytech Co.) for their support with the SGV-CL device. The research was conducted under Scientific Research Permit number 18059, issued by the National Oceanic and Atmospheric Administration under the Marine Mammal Protection Act

    Photogrammetry of blue whales with an unmanned hexacopter

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    Author Posting. © Society for Marine Mammalogy, 2016. This article is posted here by permission of Society for Marine Mammalogy for personal use, not for redistribution. The definitive version was published in Marine Mammal Science 32 (2016):1510–1515, doi:10.1111/mms.12328.Baleen whales are the largest animals ever to live on earth, and many populations were hunted close to extinction in the 20th century (Clapham et al. 1999). Their recovery is now a key international conservation goal, and they are important in marine ecosystems as massive consumers that can promote primary production through nutrient cycling (Roman et al. 2014). However, although abundance has been assessed to monitor the recovery of some large whale populations (e.g., Barlow et al. 2011, Laake et al. 2012) many populations are wide-ranging and pelagic, and this inaccessibility has generally impeded quantitative assessments of recovery (Peel et al. 2015). To augment traditional abundance monitoring, we suggest that photogrammetric measures of individual growth and body condition can also inform about population status, enabling assessment of individual health as well as population numbers. Photogrammetry from manned aircraft has used photographs taken from directly above whales to estimate individual lengths (Gilpatrick and Perryman 2008) and monitor growth trends (Fearnbach et al. 2011), and shape profiles can be measured to assess body condition to infer reproductive and nutritional status (e.g., Perryman and Lynn 2002, Miller et al. 2012). Recently, Durban et al. (2015) demonstrated the utility of an unmanned hexacopter for collecting aerial photogrammetry images of killer whales (Orcinus orca); this provided a noninvasive, cost-effective, and safe platform that could be deployed from a boat to obtain vertical images of whales. Here we describe the use of this small, unmanned aerial system (UAS) to measure length and condition of blue whales (Balaenoptera musculus), the largest of all whales.María Francisca Cortés Solari; Rafaela Landea Briones; MERI Foundation; Woods Hole Oceanographic Institution Acces
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