The phytoplankton of the Cook Plant monthly minimal surveys during the preoperational years 1972, 1973, and 1974 / by John C. Ayers.

METHODS

Figure 1 shows the collection stations used in the minimal monthly surveys
during 1974. It was not possible to occupy all stations in all months of the
field season, because on some sampling days heavy construction equipment was
working on some of the station positions. Unexpectedly, station DC-O was unsamplable in April and September because of the temporary (but real) presence
of dredging barges anchoring there. Collections of phytoplankton were not made
in November because bad weather (requiring staying in harbor) had exhausted the
available time of the R/V MYSIS.
At all stations other than DC-O, collections were made by Niskin bottle at
one meter of depth; at station DC-O a liter brown polyethylene bottle was held
by hand below the water surface until filled. All samples were of one-liter
volume and preserved with Utermbhl's iodine solution with 25 ml of glacial
acetic acid per liter added.
The samples from station collections of April through June of 1972 were
counted and identified by the Uterm6hl settling chamber and inverted microscope
method.
In the laboratory, each sample was concentrated to 100 ml by settling in a
1000-ml graduate cylinder and siphoning off 900 ml of fluid. The concentrated
sample was stored in a 100-ml opaque bottle.
Samples were prepared for counting by placing an aliquot of the concentrated sample in a tubular combination settling and counting chamber and
allowing the aliquot to settle overnight. The counting chamber containing the
settled cells was then separated from the settling chamber, covered, and placed
on the microscope. The samples were counted on a binocular inverted microscope
at 100OX magnification.
Solitary species, green and blue-green algae colonies, and the filaments
of filamentous forms were each counted as one cell. Each colonial diatom cell
was counted except when the size of the filaments or colonies prohibited counting the individual cells; in this case, the number of individual cells was
estimated.
Beginning with July of 1972 (erroneously reported as 1973 in Seibel and
Ayers 1974) and continuing since, the samples were prepared for examination by

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