CONTENTS Introduction Methods Results and Discussion Acknowledgements References Cited
Northeast Fisheries Science Center Reference Document 13-12
An Atlas of the Dominant Zooplankton Collected Along a Continuous Plankton Recorder Transect Between Massachusetts USA and Cape Sable NS, 1961-2008Jack W. Jossi and Joseph Kane
NOAA, National Marine Fisheries Service, Northeast Fisheries Science Center, 28 Tarzwell Drive, Narragansett, RI 02882
Web version posted December 13, 2013Citation: Jossi JW, Kane J. 2013. An atlas of the dominant zooplankton collected along a Continuous Plankton Recorder transect between Massachusetts USA and Cape Sable NS, 1961-2008. US Dept Commer, Northeast Fish Sci Cent Ref Doc. 13-12; 104 p. Available from: National Marine Fisheries Service, 166 Water Street, Woods Hole, MA 02543-1026, or online at http://nefsc.noaa.gov/publications/
Information Quality Act Compliance: In accordance with section 515 of Public Law 106-554, the Northeast Fisheries Science Center completed both technical and policy reviews for this report. These predissemination reviews are on file at the NEFSC Editorial Office.
From 1961 through 1974 the Oceanographic Laboratory in Edinburgh, Scotland, conducted monthly monitoring of the zooplankton and larger phytoplankton between Cape Sable, Nova Scotia and Boston, Massachusetts using the Hardy Continuous Plankton Recorder (CPR) (Hardy, 1939). In 1972 the U.S. National Marine Fisheries Service (NMFS), and the U.K. National Environmental Research Council developed an Aide Memoir for the extension of the long-term CPR survey into additional areas of the western North Atlantic, and for the joint development of instrumented towed bodies to use in this survey. On the U.S. side the resulting monitoring program has been designated as the Ships of Opportunity Program, or SOOP, currently operated by the Oceanography Branch of the Northeast Fisheries Science Center. In the U.K. the program is termed the Continuous Plankton Recorder Survey, and is now managed by the Sir Alister Hardy Foundation for Ocean Science (SAHFOS) in Plymouth, England. The four SOOP monthly sampling routes along the U.S. northeast coast that have resulted from this cooperation, as well as SAHFOS routes in the northwest Atlantic are illustrated in Figure 1, with details of the routes off the northeast coast of the United States presented in Table 1.
In 1978, as part of an agreement with the U.S. Maritime Administration (MARAD) and the NOAA National Ocean Service (NOS), concurrent measurements of water column temperature and surface salinity were added. In 1991, through SAHFOS, depth, temperature, salinity, and chlorophyll measurements were added to the CPRs towed on the Georges Bank route, and through NOS, near surface temperature and salinity measurements were added for all routes.
This atlas presents detailed methods used for the collection of the CPR and the concurrent temperature and salinity data along the Gulf of Maine route. It describes the CPR samples identification, staging, and counting, and the quality control steps employed on the CPR, and the concurrent environmental data. The resulting database content and specifications are also described. Techniques used for deriving means, variances, annual peak abundances, and anomalous conditions are described in the methods. In graphic form, the atlas presents time-space mean conditions for thirty-one of the most dominant zooplankton organisms, plus total zooplankton, along the Gulf of Maine SOOP transect for the base period of 1978 through 2007. Over the time span of 1961 through 2008 it presents changes in the seasonal cycle, and time of annual maximum abundance for each taxon within three sections (Massachusetts Bay, central Gulf of Maine, and western Scotian Shelf) of the transect. Within these three sections, it shows standardized anomalies of abundance of each taxon for the 1961 through 2008 time span. Also shown for these three transect sections are the annual variations of relative contribution to the total catch of the six most abundance taxa.
The derived data used in preparing the atlas, much of which involved gridding, are available as supplemental data sets, in space-delimited ascii format suitable for input to most analytical software.
This descriptive work, including nearly 50 years of data, is intended to be a reference from which more analytic hypotheses can be tested.
The Gulf of Maine Transect
Since 1961 a variety of military, academic, and commercial vessels have towed CPRs across the Gulf of Maine. Differing missions, weather and other circumstances have resulted in spatial variability between repeated transects. In addition, since 1977, regular surveys by research vessels have taken water column temperature and salinity data from the region along the transect. In 1991 a composite of all CPR samples was mapped (Fig. 2), and polygons were drawn around the scatter of samples with the object of minimizing cross-polygon variations relative to those along the polygon. The resulting Gulf of Maine polygon (Fig. 3) has corners at 43°-30'N, 71°-00'W; 43°-30'N, 65o-37'W; 43°-00'N, 65°-37'W; and 42°-00'N, 71°-00'W. Out-of-polygon CPR and concurrent temperature and salinity (taken since 1978) data are excluded from the Gulf of Maine data base. The Gulf of Maine route crosses strikingly different ecological areas, with distinct seasonal patterns, water column structure, bathymetry, and circulation. Thus, analyses of the transect as a whole can be misleading, e.g., up-trending patterns on the eastern end of the transect often coincide with down-trending patterns on the western end. To allow examination of such along-transect differences, the radial distance between a reference point at 43°-02.8'N; 64°-00.0'W and each data point (the center of a 10 n mi CPR sample) was calculated, and offset by the distance between the reference point and Boston Harbor. This provided the distance to each value from Boston Harbor. A reference position well outside of the polygon was chosen to minimize the cross-polygon curvature of like-distance data. The reference distance variable was used to extract and analyze sections of the transect, and to provide axis values for gridding of plankton, temperature, and salinity data.
Monthly sampling for phytoplankton and zooplankton with the CPR, water column temperature using expendable bathythermographs (XBTs), and salinity measurements at selected depths was the goal. Supplemental temperature and salinity data within the Gulf of Maine polygon from research vessels were generally available since 1976, every 60 days through the year, and was the sole source of 10 m salinity data. Monthly sampling by the CPR, from 1961 through 2008, averaged 71 percent, just as sampling of temperature and salinity since 1976 averaged 90 percent. Details of these coverages are shown in Appendix I.
CPR Sample Collection
Numerous descriptions of the Continuous Plankton Recorder (CPR), and the standard method employed during sample collection appear in the literature (Hardy, 1939; Batten, Clark et al, 2003; John and Reid, 2001; Jonas, Walne, Beaugrand, Gregory, and Hays 2004; Reid et al, 2003; Warner and Hays, 1994; and Richardson et al, 2006). Over the course of the US CPR survey in the Gulf of Maine, towed bodies (Fig. 4) underwent the same modification from the original design to a box tail arrangement as those used at SAHFOS. This was to account for the increasing merchant ships towing speeds.
The CPR was towed by an 8 mm diameter, 6x7 galvanized cable, leading inboard to a davit and block affixed to the stern quarter of the cooperating vessel, and then to a mooring capstan. A launch position was set for each transect. With the vessel running at normal cruising speed (ranging from 15-28 km/hour (8-15 knots)), the CPR was launched, and the towing wire was paid out until a whipping approximately 22 m from the CPR reached the water's surface. This resulted in the CPR sampling at somewhere between 7 and 10 m, depending on the vessel's cruising speed. Except for severe weather or other problems, the towing wire and body remained unattended until the recovery position. While towing, water enters the body through a 1.27 cm square aperture, passes through an expanding tunnel to reduce the flow rate, encounters a band of 60 XXXX silk bolting cloth with aperture of 270 μm (225 x 235 μm when wet) crossing the tunnel, and exits at the rear of the device. The filtering silk is slowly moved across the tunnel by connection to an external impeller, driven by the movement of the CPR through the water. After leaving the tunnel, this filtering silk is joined by a covering silk sandwiching the plankton between them. The double band of silk and plankton is then wound onto a take-up spool in a tank containing formalin. A continuous sample of the plankton along the vessel track is obtained, where approximately 10.16 cm (4 inches) of silk sandwich represents 10 nautical mile (n mi) of track distance and 2.876 m3 of water filtered. This volume is based on 100% filtration of a 0.0127 m x 0.0127 m x 18520 m cuboid. It should be noted that due to the continuously moving silk, each sample contains plankton from a 15 n mi length of the transect, with 25% from the first 5 n mi section, 50% from the central 5 n mi section, and 25% from the last 5 n mi section (Richardson et al, 2006). Upon retrieval, the CPR is secured on deck until returning to port where it is checked, unloaded and replaced/re-outfitted by a survey representative.
CPR Sample Processing
Navigation and Sample Definition
Logged information was exposed to range and reasonableness checking, e.g., speed of the vessel was calculated between logged times and positions. Once the logged data were considered clean, the time and position of the CPR launch, the intervening XBT stations, and the CPR haul were used to determine the total distance sampled by the CPR. This value combined with the length of silk filtering material which crossed the tunnel, permitted the division of the silk into 10 n mi pieces. Software calculated the location for marking and cutting the continuous silk record into 10 n mi sections. These samples, termed "blocks" by SAHFOS, are termed substations in the US database, to distinguish them from the stations, e.g., XBT, which were collecting data and were being logged while the CPR was being towed. The time, date, latitude, and longitude of the center point of each substation was calculated. Each was labeled as a day or night sample on the basis of local sunrise and sunset, and the substation's time and position.
After cutting the silk into 10 n mi pieces, a section of the silk may remain which was too short to make into a 10 mile block, but which sampled an appropriate amount of water for the length it did sample. If this short sample (partial block) represents at least 2.5 n mi along the tow path, it is processed, and will occasionally be analyzed and added to the data base to fill gaps in the spatial coverage, or provide information about unusual conditions.
Identification and Staging
No less than alternate substations were examined from each monthly occupation of the transect. When unusual taxa appeared, or significant ecosystem events were suspected, additional substations were examined. The two SAHFOS standard zooplankton examinations were performed on each sample, as thoroughly described by Richardson et al (2006). These examinations have remained unchanged for Gulf of Maine CPR samples. The first examination is a stepped traverse (Fig. 5) of the filtering and covering silk to enumerate the smaller zooplankton (those less in size than Metridia lucens, c. 5, or approximately < 2 mm total length). Different microscopes were used over the history of this survey resulting in a varying fraction of the silks being examined. Stage micrometer measurements of each microscope's field diameter during the traverse were made and used to determine the fraction of the silk actually examined. For different microscopes 1/43rd, 1/46th, and 1/48th of the silk were examined. This contrasts to SAHFOS, where a fixed 1/50th fraction was used.
These different fractions were used in calculating the abundances for their respective samples. The inverse of these fractions (aliquot factors), are used when calculating sample abundance.
Maintenance of the CPRs includes adjustments to produce a movement of silk across the CPR tunnel of 9.16 cm (4 inches) of silk/10 n mi of towing. However, the achieved silk transport rates vary. Departures from the ideal 4 inches/10 n mi affect the fraction of the silk examined during the traverse. These departures, termed correction or scaling factors, are expressed as the ratio between actual length and the ideal length, and generally range from 0.7 to 1.3. Rather than applying them to the aliquot factors, mentioned above, these correction factors are applied to traverse counts prior to assignment to a counting category (see below).
Samples from the 1961-1974 period were examined at the Edinburgh Oceanographic Laboratory (predecessor of SAHFOS). Subsequent samples were examined at the Narragansett Laboratory and at the Morski Instytut Rybacki (MIR) laboratory in Gdynia, Poland. In all cases, a category system of counting was employed (Table 2). Counts of each taxon/stage seen in the traverse were first multiplied by the correction factor, and were then assigned to a category representing a somewhat geometric progression of count ranges. An experienced analyst can sometimes avoid counting all individuals in the traverse when, e.g., part way through the traverse it becomes obvious that there are more than 500, but less than 1000 individuals of the taxon/stage-- a category 10 is assigned. This time saving technique was used prior to 2000, after which all individuals in the traverse and eyecount were enumerated.
The second examination of CPR zooplankton is termed an eye count, where all individuals greater than Metridia lucens, c.5 in size (>2mm in total length) are counted. Eye counts were not adjusted by a correction factor since organisms on the entire silk were counted. Results of the eye count were assigned to a category according to Table 2 as with the traverse,
More than 100 taxa and stages have been encountered on the Gulf of Maine transect (App. II). The level to which the organisms were identified and staged was largely based upon log sheets in use at the Edinburgh Oceanographic Laboratory in 1972. Sample examinations at Narragansett and in Poland logged counts to these predetermined taxa/stages. Entries where no preprinted taxon/stage was available were written in; no attempt at lower level identification or refined staging beyond the predetermined levels was made. In large part this was to maintain time series consistency for as large a list of taxon/stages as possible. As non-printed taxa/stages became common in the samples they were added to the log sheets, and the start date of their consistency documented.
Substation data were added to a data base, linkable to separate, CPR phytoplankton, and CPR zooplankton data bases (not reported on here) by the variables, cruise name (CRUNAM) and substation (SUBSTA).
Category values from both the traverse and the eye count were converted to "accepted values" according to Table 2. These accepted values were not the arithmetic mean of each count range, but rather the result of actual counts performed on samples collected in 1938 and 1939 (Rae and Rees, 1947). Further explanation of accepted values can be found in Warner and Hays (1994). For traverse records, the accepted values are multiplied by the microscope-specific aliquot factors described above. For eye count records no adjustment for aliquots is required. The resulting records then contain the number of each taxon/stage per sample (equivalent to number/block for SAHFOS samples). Since (1) partial blocks (samples less than 10 n mi) are occasionally analyzed, and (2) there was an initial desire to compare CPR abundance data with research vessel data from Bongo nets (Posgay and Marak, 1980), the number of each taxon and stage per sample is also normalized to units of #/100m3.
Temperature and Salinity Data Collection
Beginning in 1978 water column temperature (expendable bathythermograph-XBT) and surface salinity measurements were taken at hourly intervals along the Gulf of Maine transect, and in 1991 thermosalinographs were installed in the towing vessels to increase the horizontal, spatial resolution of these measurements (Appendix I). At this same time the US was conducting research vessel surveys of the northeast continental shelf, six to twelve times per year (Jossi and Marak, 1983; Jossi and Griswold, 2000). The water column temperature and salinity data within the polygon surrounding the Gulf of Maine transect from the research vessel surveys was extracted to supplement the concurrent data collected by the ships of opportunity (included in Appendix I).
Temperature and Salinity Data Processing
Early XBT collections involved the digitization of analog traces. Minimum values retained were surface, inflection points, and the bottom (if reached). Since the 10 m towing depth of the CPR didn't always coincide with a temperature inflection point, 10 m temperature often had to be estimated by linear interpolation between the values surrounding 10 m. With the advent of digital XBT recording, a 10 m temperature was kept in addition to the inflection points, if necessary. Temperature and salinity data from research vessel surveys initially came from bottle casts, sometimes making 10 m interpolation necessary. After the introduction of conductivity-temperature-depth (CTD) instruments these values were measured directly. For further details on the collection of these data, see Benway, et al, 1993 and Taylor and Bascunan, 2000.
Calculations and calibrations involved in the use of XBT and CTD data followed recognized international standards, and will not be repeated here. See Steinhart and Hart (1968); Georgi et al (1981); UNESCO (1981); and Benway et al (1993). The station, the depth-temperature pairs, and the depth-salinity pairs data are added to an environmental data base, which is linkable to the CPR data bases by the variable, reference distance (REFDST). See Gridding section below for a description of reference distance.
To overcome problems associated with irregular sampling in both space and time, both the physical and biological data were subjected to a gridding procedure. The design of the gridding method was developed in part with other research at the NOAA Narragansett Laboratory (Goulet, 1990; Jossi et al, 1991; Thomas, 1992). For each irregular raw data matrix, the gridding technique was used to calculate a curved planar surface from interpolated data values at regular, spatial-temporal grid points. Reference distance was used as the spatial variable; yearday (decimal value of the sample's day within a year containing 354.25 days) and decimal year were used as temporal variables. Those gridded data values were contoured, producing three-dimensional representations of space by time by scalar. Furthermore, gridding was used to calculate mean values and standard deviations over a 30 year base period (1978 though 2007); and to compare individual-year data to base period mean values, via algebraic anomalies and standardized anomalies. Additionally, time (yearday) by time (decimal year) by scalar grid were generated to examine the multidecadal variations of seasonality for the different data types. Physical data exposed to gridding was used without transformation. To produce more normal distributions, biological data were transformed to logarithmic values as follows:
Log Value= log10(#/100m3 +1)
Because the grid dimensions were uniform for all data types, the grids could be exposed to matrix algebra, e.g., calculations of correlation coefficients between grids. A graphical representation of the gridding process is shown in Figure 6, and a complete set of parameters for the difference grids is listed in Table 3.
Base Period Mean Grids
Grids were defined by time (range: 0-365.25 days) along the x-axis, and polygon reference distance (range: 0-452 km) along the y-axis. The x-axis maximum of 365.25 was used to account for leap years and to permit calculations on multiyear files. The grids were dimensioned such that grid points occurred at intervals of 7.609 days and 8.692 km. At every grid point, a z-value was calculated by performing an elliptical search of 15 days and 38 km for all data occurring from 1978 through 2007, and calculated the arithmetic mean of the data found. In the event of fewer than one observation within the search ellipse at a given point, that grid point was assigned a missing value, which likewise produced missing values for that grid point in any subsequent derivations.
Standard Deviation Grids
Gridding parameters used in producing standard deviation grids were identical to those employed for base period mean grids, resulting, among other things, in identical data sets used for mean and std calculations at each grid point.
Base period mean grids were replicated sufficient times to cover the number of years for which anomalies were to be calculated. The time, or x-axis of the replicated grid was rescaled to decimal year values, resulting in an axis range for this atlas of 1961 to 2009.0 (cpr data), and 1976.0 to 2009.0 (temperature and salinity data). The base period mean grid surface value at each of the irregularly spaced observed data locations was subtracted from these observed values to produce a data set of residuals. Residuals were at the observed time-space locations. Gridding the residuals produced a multiyear anomaly grid defined by time (range: 1961.0 or 1978.0 to 2009.0 years) along the x-axis, and polygon reference distance (range: 0-452 km) along the y-axis. Grid points continued to occur at 7.609 day (0.0208 year), and 8.692 km intervals. Note that some gridding parameters used for anomaly gridding differ from those used for mean grids (Table 3).
To standardize the anomalies, standard deviation grids were replicated in the same manner as were the mean grids, described above. The anomaly grids were then divided by the standard deviation grids to produce Zscore grids having identical dimensions as anomaly grids.
The time-space grids so far produced indicate significant along-transect variation. Since the seasonality grids have no spatial component, they are produced for sections of the transect where cluster and other analyses has shown spatially coherent features (Thomas, 1992). These grids were defined by time (range:-365.25 to 0 days along the x-axis, and time (range: 1961.0 or 1978.0 to 2009.0 years) along the y-axis. For portrayal, these grids were rotated 90o clockwise, with absolute values of yearday used for axis labels. Thus, portrayals appear to have decimal year increasing to the right on the x-axis, and positive yearday increasing upwards on the y-axis. The grids were dimensioned such that grid points occurred at intervals of 7.609 days in both dimensions. See Table 3 for gridding method and parameters. As with all grids, in the event of fewer than one observation within the search ellipse at a given point, that grid point was assigned a missing value, which likewise produced missing values for that grid point in any subsequent derivations. Seasonality grids were generated for the Massachusetts Bay (reference distance 0-96 km), central Gulf of Maine (reference distance 96-339 km), and western Scotian Shelf (reference distance 339-452 km).
Annual Peak Abundance
Portrayals of the seasonality grids suggest variations in the timing of seasonal events between years. To further explore these variations a center of gravity of the yearday producing the highest annual abundance was calculated for each year. To avoid bias due to differing coverage in different years, the input data set for this calculation was obtained by extracting the interpolated abundances for each grid point in the seasonality grids. Annual center of gravity values were obtained by the following steps/calculations:
Weighted abundance= grid abundance * yearday
Grid abundances and weighted abundance were then summed by year.
Center of gravity= weighted abundance sum/grid abundance sum
Center of gravity values were then plotted against year for the three sections of the Gulf of Maine transect.
Zscore Time Series
To illustrate the significance and persistence of abundance departures from the base period, monthly Zscores were calculated for the three sections of the Gulf of Maine transect. For those years with missing monthly abundance values (YerMonMean), interpolated values were calculated if three or more of the highest six base period months were sampled in that year. Zscore values were generated by the following steps/calculations:
MonMean= mean abundance for each of the 12 months using 1978 through 2007 data.
MonStd= standard deviation of the mean abundance for each of the 12 months using 1978 through 2007 data.
Interpolated YerMonMean values = (sum of abundances of the three or more high-six months sampled in the year) / sum of the base period mean abundances for the same months) x the missing months base period mean value.
YerMonZscore= (YerMonMean - MonMean) / MonStd
Year and month values were combined to create decimal year values.
Monthly Zscore values were then plotted against year for the three sections of the Gulf of Maine transect.
Relative Contribution of Taxa
The annual contributions of the six top-ranking taxon/stages to the total catch through the time series were calculated. This was done only for those years where, either all months were sampled, or where missing months could be interpolated using the technique described for the Zscore time series, above. Cumulative percentages were then calculated for the six taxon/stages plus the remaining (other) components of the catch.
The results consist of two major parts. The first, contained in this document, describes collection and processing methods used for the biological and physical data, and provides graphical depictions of the biological data. The second part consists of supplemental data sets used in preparing the atlas which may be useful for further analysis.
Part 1 is made up of graphical depictions of variations of thirty-one of the most dominant zooplankton taxa/life stages (in descending order of overall abundance), plus total zooplankton, during the period 1961 through 2008. These results are arranged with the intention of viewing each taxon/life stage as a two-page series beginning with Figure 7, and continuing through Figure 38. (To see these figures in their intended layout, download the full pdf with Adobe Acrobat and select the "two-page view" display.) The first page consists of two panels. Panel I, "1978 - 2007 Mean Abundances," portrays time-space mean abundances for the entire transect, with the three coherent sections of the transect indicated along the x-axis. Panel I is based on the Mean Grid. Panel II, "Interannual Variations of Seasonality," presents contoured abundances by yearday over the time span of 1961 through 2008 for the three sections of the transect. These contoured graphs are based on the Seasonality Grids. The bottom of panel II shows the annual day of maximum abundance (center of gravity) for the above three transect sections and time span. Panel III begins on the second page with "Interannual Departures from Mean Abundances." This illustrates monthly Zscores during the period 1961 through 2008 for the three sections of the Gulf of Maine transect.
Note: Standardized anomaly values for taxa with large numbers of observed abundances equal to, or near zero, raises the question of whether near normal data distributions are obtained via the logarithmic transformations. Thus, more emphasis should be put on the persistence of anomalies than on their absolute values.
Panel IV, "Comments," provides discussion of the more significant taxon/stage time and space distributions presented on these two pages.
An additional part 1 product consists of graphs and comments on the annual relative contribution of the six most abundant taxa to the total catch, for the three sections of the Gulf of Maine between 1961 and 2008 (Figures 39-41).
Part 2 consists of ascii grid files for each of the graphical depictions and for related statistics, e.g., standard deviations grids for each mean grid. Grid files are also presented for 10 meter temperature and 10 meter salinity values with grid dimensions identical to those of the biological files. These files, along with documentation are available at:
Requests for raw data from the Continuous Plankton Recorder survey should be directed to:
Chief, Oceanography Branch U.S. Department of Commerce National Oceanic and Atmospheric Administration Northeast Fisheries Science Center Narragansett RI 02882
Since its beginning on the Northeast Continental Shelf, dozens of commercial, military, academic and private vessels have participated in the Continuous Plankton Recorder survey. The enthusiasm and dedication of hundreds of officers and crew members, and the generosity of the owners have been the major factor in this program's success. Current collaborators for the Gulf of Maine route are Eimskipafelag, Icelandic Steam Shipping Company, Reykjavik, Iceland; NOAA National Weather Service; NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML); and Sir Alister Hardy Foundation for Ocean Science, Plymouth, U.K.
The staff of the Oceanographic Laboratory, Edinburgh completed all the examinations of Gulf of Maine samples for the period 1961-1974, and generously shared these data with us. That staff, and succeeding staffs of SAHFOS continued this generosity in the areas of logistics, sample design, data processing and analyses until the present time.
Since 1998, staff at the Zaklaad Sortowania I Oznaczania Planktonu in Gdynia and Szczecin Poland, examined all Gulf of Maine CPR samples. Their professionalism and volume of timely data products have provided a key link in the program's success.
In the northeast United States, Robert Marak and John Colton, used CPR's in the Gulf of Maine in the 1950s to collect fish eggs and larvae contributing greatly to the early years of the program at Narragansett. William Brennan delivered CPR's to ships for us before he went on to become director of the National Marine Fisheries Service. Steven Cook joined us, bringing with him the Ships of Opportunity Program, which was making physical oceanographic measurements from merchant ships in the North and South Atlantic and Gulf of Mexico. Chris Melrose and Jon Hare, more recently have joined the survey and have applied technology and fresh ideas that have been needed for a long time.
Last, but by far not least, we want to express our thanks to Robert Benway, Julien Goulet, Daniel Smith, Carolyn Griswold, and Jay O'Reilley. Until his recent retirement, Bob ran the survey like a fine watch. There was not a detail he didn't worry about, a gesture to a ship's captain and crew that he forgot about, or a loose end he didn't tend to. Given the simplest or most complex problem, Julien became silent, went to the blackboard, and produced the equations that settled the issue. His English was just fine, but his mathematics were superb. Daniel, in the early years produced the plankton data from hundreds of CPR cruises, maintained the towed bodies and loaded, and still loads, the internal mechanisms. His corporate memory has saved the day many times. Carolyn recruited volunteers to ride the volunteer ships, made computer runs and filed the data making analyses so much easier. Jay's continuing interest in the survey resulted in numerous improvements to data quality, and especially to the quality of the atlas graphics.
All mentions of brand names are used for descriptive purposes only and do not imply endorsement by the federal goverment.
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