Development and assessment of a new dermal attachment for short-term tagging studies of baleen whales

© The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Methods in Ecology and Evolution 6 (2015): 289–297, doi:10.1111/2041-210X.12325.Current studies of fine-scale baleen whale diving and foraging behaviour rely on archival suction cup tags that remain attached over time scales of hours. However, skin irregularities can make suction cup attachment unreliable, and traditional pole deployment of suction cup tags is challenging in moderate sea conditions or when whales are evasive. We developed a new tag attachment to overcome these limitations. The attachment features a short (6·5–7·5 cm) needle that anchors in the whale's dermis (epidermis and blubber) to which a free-floating tag is attached via a severable tethered link. The needle, tag and a detachable ‘carrier rocket’ with fletching are fitted together to form a projectile that can be deployed at distances of up to 20 m using a compressed-air launcher. A corrosive release mechanism allows the tag to separate from the needle after a specified period of time so that the tag can be recovered. The dermal attachment was evaluated during a study of humpback whales (Megaptera novaeangliae) in the Gulf of Maine and then subsequently deployed on bowhead whales (Balaena mysticetus) near Barrow, Alaska. Monitoring of tagged humpback whales indicated that the needle was shed several days after deployment, the attachment site healed shortly thereafter, and there were no discernible behavioural or health effects over time scales of days to months after tagging. Bowhead whales showed little immediate reaction to tagging; the most common response was a prolonged dive right after tag deployment. On average, respiration rates of tagged bowhead whales were elevated after tag attachment, but returned to the same rate as undisturbed bowheads within 1–1·5 h. When compared to suction cups, the dermal anchor provided a more reliable attachment and it can be applied from greater distances and in rougher sea conditions; it is therefore a useful alternative in circumstances where suction cup tags cannot be easily deployed.This study was funded by the U.S. Department of the Interior, Minerals Management Service (MMS; now Bureau of Ocean Energy Management), through Inter-agency Agreement No. M08PG20021 with the U.S. Department of Commerce, National Oceanic and Atmospheric Administration, as part of the MMS Alaska Environmental Studies Program

A modified wire clamp system for thirty-liter Niskin bottles

A modified clamping system for 30-liter Niskin bottles, consisting of a wire stop, a socket block, and a toggle clamp, has been designed and has been tested at sea. The modified system makes deployment and recovery of the Niskin bottles considerably easier than it is with the standard clamps .Funding was provided by the National Science Foundation under grant Number OCE 84-17910, and by the United States Department of Energy under contract Number DE-AC02-76EV03566

A large-volume, deep-sea submersible pumping system

Eight self-contained, in-situ pumps have been used effectively and routinely by our group for the past six years to collect both particulate and dissolved phases from large volumes of sea water. Multiple pumps are rapidly and easily deployed on the same wire, to any ocean depth, in almost any weather. Each is capable of drawing up to 200 liters per hour through four large Nuclepore™ filters, then through three cartridge filters. Pumping is controlled by a Sharp™ pocket computer suitably interfaced with the pump motor and flow meter. Endurance is about 15 hours. Total flow and flow rate are recorded, respectively, by a mechanical flow meter and the computer.Funding was provided by the National Science Foundation under Grant Number NSF OCE-8800620 and the Department of Energy under Grant DE-FG02-88ER60681

Assessing algal biomass and bio-optical distributions in perennially ice-covered polar ocean ecosystems

AbstractUnder-ice observations of algal biomass and seasonality are critical for understanding better how climate-driven changes affect polar ocean ecosystems. However, seasonal and interannual variability in algal biomass has been studied sparsely in perennially ice-covered polar ocean regions. To address this gap in polar ocean observing, bio-optical sensors for measuring chlorophyll fluorescence, optical scattering, dissolved organic matter fluorescence, and incident solar radiation were integrated into Ice-Tethered Profilers (ITPs). Eight such systems have been deployed in the Arctic Ocean, with five profilers completing their deployments to date including two that observed an entire annual cycle in the central Arctic Ocean and Beaufort Sea respectively. These time series revealed basic seasonal differences in the vertical distributions of algal biomass and related bio-optical properties in these two regions of the Arctic Ocean. Because they conduct profiles on daily or sub-daily scales, ITP bio-optical data allow more accurate assessments of the timing of changes in under-ice algal biomass such as the onset of the growing season in the water column, the subsequent export of particulate organic matter at the end, and the frequency of intermittent perturbations, which in the central Arctic Ocean were observed to have time scales of between one and two weeks

A differential pressure instrument with wireless telemetry for in-situ measurement of fluid flow across sediment-water boundaries

© 2009 The Authors. This article is distributed under the terms of the Creative Commons Attribution (3.0) License. The definitive version was published in Sensors 9 (2009): 404-429, doi:10.3390/s90100404.An instrument has been built to carry out continuous in-situ measurement of small differences in water pressure, conductivity and temperature, in natural surface water and groundwater systems. A low-cost data telemetry system provides data on shore in real time if desired. The immediate purpose of measurements by this device is to continuously infer fluxes of water across the sediment-water interface in a complex estuarine system; however, direct application to assessment of sediment-water fluxes in rivers, lakes, and other systems is also possible. Key objectives of the design include both low cost, and accuracy of the order of ±0.5 mm H2O in measured head difference between the instrument’s two pressure ports. These objectives have been met, although a revision to the design of one component was found to be necessary. Deployments of up to nine months, and wireless range in excess of 300 m have been demonstrated

Design and operation of automated ice-tethered profilers for real-time seawater observations in the polar oceans

An automated, easily-deployed Ice-Tethered Profiler (ITP) has been developed for deployment on perennial sea ice in polar oceans to measure changes in upper ocean temperature and salinity in all seasons. The ITP system consists of three components: a surface instrument that sits atop an ice floe, a weighted, plastic-jacketed wire-rope tether of arbitrary length (up to 800 m) suspended from the surface instrument, and an instrumented underwater unit that profiles up and down the wire tether. The profiling underwater unit is similar in shape and dimension to an ARGO float except that the float's variable-buoyancy system is replaced with a traction drive unit. Deployment of ITPs may be conducted either from ice caps or icebreakers, utilizing a self contained tripod/winch system that requires no power. Careful selection of an appropriate multiyear ice floe is needed to prolong the lifetime of the system (up to 3 years depending on the profiling schedule). Shortly after deployment, each ITP begins profiling the water column at its programmed sampling interval. After each acquired temperature and salinity profile, the underwater unit (PROCON) transfers the data and engineering files using an inductive modem to the surface controller (SURFCON). SURFCON also accumulates battery voltages, buoy temperature, and locations from GPS at specified intervals in status files, and queues that information for transmission at the start of each new day. At frequent intervals, an Iridium satellite transceiver in the surface package calls and transmits queued status and CTD data files onto a WHOI logger computer, which are subsequently processed and displayed in near-real time at http://www.whoi.edu/itp. In 2004 and 2005, three ITP prototypes were deployed in the Arctic Ocean. Each system was programmed with accelerated sampling schedules of multiple one-way traverses per day between 10 and 750-760 m depth in order to quickly evaluate endurance and component fatigue. Two of the ITPs are continuing to function after more than 10 months and 1200 profiles. Larger motor currents are observed at times of fast ice floe motion when larger wire angles develop and drag forces on the profiler are increased. The CTD profile data so far obtained document interesting spatial variations in the major water masses of the Beaufort Gyre, show the double-diffusive thermohaline staircase that lies above the warm, salty Atlantic layer, and many mesoscale eddys. Deployed together with CRREL Ice Mass Balance (IMB) buoys, these ITP systems also operate as part of an Ice Based Observatory (IBO). Data returned from an array of IBOs within an Arctic Observing Network will provide valuable real time observations, support studies of ocean processes, and facilitate numerical model initialization and validation.Funding was provided by the National Science Foundation under Contract Nos. OCE-0324233 and ARC-0519899

Protocols for calibrating multibeam sonar

Author Posting. © Acoustical Society of America, 2005. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 117 (2005): 2013-2027, doi:10.1121/1.1869073.Development of protocols for calibrating multibeam sonar by means of the standard-target method is documented. Particular systems used in the development work included three that provide the water-column signals, namely the SIMRAD SM2000/90- and 200-kHz sonars and RESON SeaBat 8101 sonar, with operating frequency of 240 kHz. Two facilities were instrumented specifically for the work: a sea well at the Woods Hole Oceanographic Institution and a large, indoor freshwater tank at the University of New Hampshire. Methods for measuring the transfer characteristics of each sonar, with transducers attached, are described and illustrated with measurement results. The principal results, however, are the protocols themselves. These are elaborated for positioning the target, choosing the receiver gain function, quantifying the system stability, mapping the directionality in the plane of the receiving array and in the plane normal to the central axis, measuring the directionality of individual beams, and measuring the nearfield response. General preparations for calibrating multibeam sonars and a method for measuring the receiver response electronically are outlined. Advantages of multibeam sonar calibration and outstanding problems, such as that of validation of the performance of multibeam sonars as configured for use, are mentioned.Support by the National Science Foundation through Award No. OCE-0002664, NOAA through Grant No. NA97OG0241, and the Cooperative Institute for Climate and Ocean Research (CICOR) through NOAA Contract No. NA17RJ1223 is acknowledged

In Situ Sensor Technology for Simultaneous Spectrophotometric Measurements of Seawater Total Dissolved Inorganic Carbon and pH

A new, in situ sensing system, Channelized Optical System (CHANOS), was recently developed to make high-resolution, simultaneous measurements of total dissolved inorganic carbon (DIC) and pH in seawater. Measurements made by this single, compact sensor can fully characterize the marine carbonate system. The system has a modular design to accommodate two independent, but similar measurement channels for DIC and pH. Both are based on spectrophotometric detection of hydrogen ion concentrations. The pH channel uses a flow-through, sample-indicator mixing design to achieve near instantaneous measurements. The DIC channel adapts a recently developed spectrophotometric method to achieve flow-through CO₂ equilibration between an acidified sample and an indicator solution with a response time of only ∼90 s. During laboratory and in situ testing, CHANOS achieved a precision of ±0.0010 and ±2.5 μmol kg^–1 for pH and DIC, respectively. In situ comparison tests indicated that the accuracies of the pH and DIC channels over a three-week time-series deployment were ±0.0024 and ±4.1 μmol kg^–1, respectively. This study demonstrates that CHANOS can make in situ, climatology-quality measurements by measuring two desirable CO₂ parameters, and is capable of resolving the CO₂ system in dynamic marine environments