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Time-series Photographs of the Sea Floor in Western Massachusetts Bay, Version 2, 1989 - 1996 Skip navigational side bar


Notes on Individual Time-series

This section includes a list of comments for each set of time-series photographs. The comments provide explanations for some of the characteristics of the photographs, identification of some of the animals, and descriptions of some of the changes observed on the sea floor. To quickly scan the entire time series, drag the slider in movie players Quicktime or Imagen with the mouse.

Time-series 338 (December 5, 1989 - March 28, 1990)

  • No oceanographic data are available for this deployment because of a failure in the data-recording electronics. Thus the data panel beneath the photograph is blank. Beam-attenuation data begin in frame 235.
  • The red haze in the upper right corner of the movie frame is an artifact caused by light leaking from the LED data chamber and exposing the film.
  • The sea floor in several fames in this time series is poorly illuminated, for example, in frames 026-036, 132-139, and 217-227. The decreased light from the strobe may be caused by animals or plants blocking the strobe light or by some malfunction of the strobe light that produced low light for these photographs.
  • A skate remains in nearly the same location on the sea floor in frames 116-125.
  • Increased turbidity is visible in frames 228-231.
  • The 5/8-inch nylon line used to recover the tripod spills from the rope canister during the sediment resuspension event beginning in frame 228. The line is visible on the sea floor in frames 230-255 and occasionally thereafter. This tripod was recovered with the aid of divers.
  • Increased turbidity and movement of the recovery line on the sea floor is visible in frames 332-339.

Time-series 347 (July 10, 1990 - October 23, 1990)

  • The red haze in the upper right corner of the movie frame is an artifact caused by light leaking from the LED data chamber and exposing the film.
  • Resuspension events begin in frames 085 and 221 that are correlated with an increase in bottom pressure standard deviation (indicating increased surface waves).
  • Small fish begin to appear in the photographs at frame 105 and are observed throughout the remainder of the observation period, sometimes in large numbers (for example, frames 196-197).
  • The attachment for the compass fails between frames 131 and 132 and the compass falls to the sea floor.
  • Temperature, current, and speed data are lacking after frame 202 as the result of a failure in the data recording electronics.

Time-series 358 (October 24, 1990 - February 12, 1991)

  • The sea floor is illuminated by the strobe light only in a circle in the left center of the photograph. This poor lighting most likely is due to low battery power supplying the strobe. The light decreased throughout the deployment, and the illumination is not sufficient to see the sea floor by frame 300.
  • Resuspension events begin in frames 104 and 166 that are correlated with an increase in bottom pressure standard deviation (indicating increased surface waves).
  • Increased turbidity is visible, despite the poor strobe illumination, in frame 326.

Time-series 374 (February 12, 1991 - June 11, 1991)

  • The data chamber ID number was mistakenly set at 76; it should be 74 for deployment 374.
  • The lower cage of the Benthic Acoustic Stress Sensor (BASS), used to measure current, is visible at the right edge of the photograph.
  • Increased turbidity is apparent in frames 8-12, 79-81, 122-137, 272-276, and 454-460.
  • There are no temperature data after frame 129, pressure data after frame 46, light transmission data after 287, and current data after 450 as the result of failures in the data-recording electronics.
  • A large number of fish appear in the photographs from frame 280-440. Many are near the camera lens and thus appear large.

Time-series 383 (June 11, 1991 - October 15, 1991)

  • On the right side of the photograph, occasional portions of red digits are artifacts from the data chamber.
  • There is a shadow in the upper left corner of the photographs caused by something blocking the illumination from the strobe.
  • There are no temperature or beam-attenuation measurements for this deployment.
  • There are a number of small fish in the photographs starting in frame 024.
  • The illumination of the sea floor from the strobe light begins to decrease around frame 400. The illumination progressively decreases; the photographs are illuminated only in the center and are nearly black by frame 487 near the end of the deployment. The decrease in illumination most likely is due to fouling during this summer deployment, low battery power supplying the strobe, or both.

Time-series 389 (October 16, 1991 - October 30, 1991)

  • The lower cage of the BASS, used to measure current, is visible at the right center of the photograph.
  • The light red haze along the right side of the photograph is an artifact caused by light leaking from the LED data chamber.
  • Increased turbidity is apparent in frames 1-50 and 71-84.
  • The photographic and data records end during the storm that begins on October 28, 1991. The tripod frame is tipped over by the large wave currents during this storm, which was the second largest storm during the period 1990 to 2006 as determined by bottom wave stress (Butman and others, in press).

Time-series 400 (June 2, 1992 - October 10, 1992)

  • The compass in the field of view does not swivel in this deployment.
  • There is a shadow that cuts across the lower right corner of the photographs that grows more pronounced during the deployment; this most likely is caused by fouling.
  • A veneer of sediment is visible in the beginning of the deployment (for example, frame 074); much of this material appears removed by frame 500.
  • A 10-cm cobble is tipped up between frames 417 and 418.
  • Increased turbidity is apparent in frames 022- 030 and 685 - 705.
  • The data end at frame 677; the pictures continue until frame 736.

Time-series 407 (October 20, 1992 - February 18, 1993)

  • The LED data chamber is overexposed in this film making the timing digits impossible to read.
  • Increased turbidity is apparent in frames 002-016, 077-100, and 124-125.
  • The tripod is tipped over after frame 170. There is no major storm activity at this time, and it is hypothesized that the tripod may have been tipped over by entanglement with fishing gear. The camera continues to operate, although no longer pointed at the bottom, and indicates times of increased turbidity.
  • A northeast storm occurred on December 12-14, 1992; this was the largest storm during 1990 to 2006, as determined by wave bottom stress (Butman and others, in press). Increased turbidity is apparent in the frames taken during this storm.
  • Increased turbidity is apparent in frames 171-188, 222-226, 243-252, 327-333, 383-389, 408- 431, 525-537, and 589-618.
  • A lobster pot is visible after frame 253. The pot is closer to the camera after frame 409 and out of the field of view after frame 524.

Time-series 413 (February 25, 1993 - June 15, 1993)

  • The lower cage of the BASS, used to measure current, is visible at the bottom center of the photograph. The BASS sensor casts a shadow in the upper left of the photographs that increases in intensity.
  • The compass is located at the top center of the photograph and is only partly in view; the head of the compass assembly that holds the north-point arrow is not visible in all frames.
  • Three separate storms, accompanied by increases in pressure standard deviation indicating large bottom-wave currents, occur in frames 19-35, 38-48, and 75-100.
  • Following the storm in frames 38-48, finer-grained sediments have replaced cobbles in a band from the BASS sensor to the middle upper left of the photograph (part of the ring of lowest BASS sensor cage is visible in the bottom center of the photographs).
  • Increased turbidity is apparent in frames 20-33, 38-55, 76-119, 191-198, 258-262, and 344-353.
  • These are no current, temperature, or beam attenuation data following frame 129.

Time-series 420 (June 15, 1993 - October 6, 1993)

  • A crab has excavated a depression in the sediment in frame 011 and remains in the same position through frame 014 photographs (at least 12 hours). The depression is devoid of the fine-grained sediment that appears to cover the rest of the sea floor.
  • Between frames 29 and 30, there is a shift of some of the small cobbles. Since no current speed was measured at greater than 10 cm/s, it is hypothesized this movement was caused by an animal not captured in the photographs.
  • Small increases in suspended matter concentration, as indicated by the increase in beam attenuation, make the photographs appear lighter (see frames 162-165).
  • A lobster is in frame 218.
  • A sea urchin apparently removes the thin veneer of sediment on a flat cobble in frames 272-273.
  • An area in the lower left corner of the photograph was disturbed between frames 337 and 338. The disturbance is similar in appearance to the one caused by the crab in frame 011.
  • Several cunner are observed beginning in frame 419.
  • Seaweed, apparently growing on the tripod frame, is observed on the left and right sides of the photographs beginning with frame 464.
  • A crab has burrowed into the sediment in frame 573 and remains partially covered by sediment in frames 574 and 575.
  • There are no light transmission data after frame 483 and no temperature and current data after frame 616 as a result of failure of the data-recording electronics.

Time-series 428 (October 5, 1993 - February 13, 1994)

  • The cage of the BASS current sensor is visible at the bottom center of the photographs and casts a shadow in the upper left of the photographs.
  • The body of the compass is only occasionally visible at the top of the photographs.
  • The tripod is tipped over at frame 254. There were no large currents or waves at this time, and thus, some entanglement with fishing gear is hypothesized to have tipped the tripod. The camera continued to function and showed changes in water clarity.

Time-series 430 (February 15, 1994 - June 6, 1994)

  • A skate appears in frame 018.
  • A depression in the sea floor, surrounded by light-gray material, is established between frames 024 and 025.
  • Resuspension events begin in frames 054, 098, 148, 483, and 552 that are correlated with an increase in bottom pressure standard deviation (indicating increased surface waves).
  • Small flounder appear beginning at frame 323 and to the end of the deployment (frames 323, 329-330, 355, 375, 377, 399, 400, 406, 407, 424, 425, 453, 464, 517, 520-523, 527-529, 533-535, 546-547, 551, 563, 582, 595, 655, and 657).
  • A sea urchin, perhaps the same individual, appears in frames 357-388
  • An ocean pout appears in nearly the same location in frame 376-377.
  • A hermit crab appears in frame 506.

Time-series 440 (June 7, 1997 - October 4, 1994)

  • The strobe light illuminates a circle in the center of the photograph; the left side and upper right corner of the frame is poorly illuminated. The strength of the illumination varies over the deployment, possibly caused by a plant or animal partially blocking the strobe.
  • The linear shadow that extends from the lower center of the photo to the upper left is from the BASS current meter frame.
  • The compass is mounted at the very top of the photographs and is not fully visible in all of the frames.
  • Fish from the Gadidae family, most likely cod, appear throughout the deployment but appear more abundant in the first 50 or so frames (for example, frame 39).
  • Flounder appear in numerous frames, for example, 23, 79, 109, 129, 130, 135, 136, 153-155, 169, 175, 186, 221, 247, 276, 287, 353, 382, 435, 442, 521, 558, 604, and 697.
  • A sea urchin is visible in frames 104-108.
  • Increases in the suspended matter concentration, as indicated by increases in beam attenuation, cause the sea floor to appear blurred. For example, compare frame 403 with moderate beam attenuation and frame 404 with lower beam attenuation.
  • Resuspension events begin in frames 535, 644, and 656.
  • A large starfish appears in frames 602-608.

Time-series 445 (October 4, 1994 - February 11, 1995)

  • Flounder appear in frames 014, 022-024, 157, 161-163, 166-169, 201, 215-217, 221-223, 227 (in the same depression as 221-223), 252, and 634
  • A spiny sunstar appears in frame 105.
  • A lobster appears in frames 181, and 207
  • A cancer crab appears in frames 206, and 706
  • Between frames 224 and 225, a depression is excavated on the right side of the photograph; although not observed, this most likely is caused by a cancer crab.
  • A sculpin is observed in frames 228, 720, and 722.
  • The illumination from the strobe begins to decrease around frame 250; note the increasing material on the top of the compass, which could also be fouling the strobe.
  • A skate is observed in frame 286.
  • Resuspension events begin in frames 445, 485, 637, 653, and 742. Cobbles were moved during these events.
  • Dark spots appear around frame 600 and are most developed at the end of the deployment (frame 781); these most likely are caused by biological growth on the camera lens.
  • A light-tan angular object appears on the right side of the photographs in frame 506 (following the resuspension event that begins at frame 485) and is visible until the resuspension event that begins in frame 743.
  • A burrow is excavated, marked by light-gray material (to the right of the compass), beginning in frame 726.

Time-series 450 (February 15, 1995 - June 13, 1995)

  • The sea floor at this location is a gravel pavement; this tripod was deployed the farthest east mooring at LT-A (fig. 7)
  • Photographs are poorly illuminated. Some frames are brighter than adjacent frames (for example, compare frames 220-222); between frames 221 and 413, every sixth frame appears brighter (this pattern is most easily seen in the thumbnail display). The reason for this variable illumination is unknown.
  • Resuspension events begin in frames 044, 116, and 455.
  • A ocean pout appears in frames 493-496, 545, and 657-658.
  • A spiny sunstar appears in frames 699-702.

Time-series 460 (June 13, 1995 - September 26, 1995)

  • Green sea urchins are ubiquitous throughout the deployment (for example, in frames 041, 195, and 356).
  • Urchins remove sediment from the top of a flat rock several times during the deployment (for example, in frames 040-047, again in frame 86, and again in frames 551-552).
  • A spiny sunstar appears in frames 50-52.
  • A starfish appears in frames 086-090.
  • Cunner are ubiquitous throughout the deployment (beginning around frame 093, and thereafter; for example, see frames 295, 307, 325).
  • Resuspension events begin in frames 378, 499, and 598.

Time-series 462 (September 26, 1995 - February 3, 1996)

  • Resuspension events begin in frames 059, 153, 225, 283, 298, 450, 514, 598, and 627.
  • The field of view shifts slightly between frames 79 and 80.
  • A flounder appears in frame 122, a sculpin in frame 199.
  • A cobble is overturned between frame 399 and 400 during a period of low current speed.
  • A reddish object (near the camera and out of focus) appears on the left side of the photographs beginning at frame 493. The object, hypothesized to be biological growth, gets larger during the deployment and floats in and out at the left margin of the photographs.
  • A small burrow, marked by light-gray material on the surface, is observed at frame 529 and is filled in during the storm that begins at frame 598.
  • Many green sea urchins are present, for example, in frame 765.

Time-series 470 (June 11, 1996 - October 1, 1996)

  • Part of circular frame of BASS current meter is visible at bottom center of photographs.
  • The compass is only partially observed in the field of view at the top of the photograph.
  • Resuspension events begin in frames 67, 496, 565, 595, and 632.
  • A crab sits on a rock in frames 273 and 274.
  • Sculpin are ubiquitous throughout the deployment, for example, in frames 159, 243, and 586.
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