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results of scientific studies in coastal ponds also seem to be idiosyncratic, applying to the nearly unique conditions of each pond.
This conclusion leaves us with a stark choice between two options: (1) continue to manage to pond's salinity at about 2 ppt or lower, depending on the decision of the Falmouth shellfish warden, and hoping that we are doing the right thing; or (2) attempt to sponsor and promote research specifically on the salinity of Oyster Pond. This is one of the reasons we are asking OPET members to fill out a survey on priorities for OPET. Spending money on research on the effects of salinity on coontail growth, for example, |
means that there will be less money for land acquisition, education outreach, and so forth. The resources of OPET, alone, are probably insufficient to support the depth and breadth of scientific research needed to clarify the salinity management issue, but OPET could provide important seed money that would facilitate acquisition of additional research grant money. The OPET board of directors seeks your input as to where to research on how pond salinity, fish, and aquatic weeds fits into your list of priorities of OPET resources.
. . by Mindy Hall |
Between mid-January and mid-June of 2002, I collected 31 samples at the weir and 24 from the dock at Spohr's Garden. Water temperatures were recorded in centigrade; salinity samples were taken to Prof. Valiela's MBL laboratory, where salinity was determined by Marci Cole of Boston University's Marine Program.
At the weir, salinities ranged from 2 to 28 ppt (parts per thousand) and averaged 5.3 ppt.. (see sidebar). At the Spohr's Garden, dock salinities ranged from 1 to 5 ppt and averaged 3.8 ppt.
Water Temperatures were generally similar at both locations from a low of 6 degrees C in mid-January to 25 degrees C by mid-June.
I collected these samples for two reasons. I thought OPET needed more data from a time of year when the "spring bloom" or period of biological productivity was beginning for phyto and zoo plankton, underwater vegetation, and the spring spawning of fihs species, especially alewife (herring).
The other reason was to collect salinity data for Paul Montague, Town Shellfish Warden (also in charge of herring runs). Paul believes the salinties for spawning alewife should be 0 to 2 ppt, somewhat lower than the salinities I collected (see above).
OPET has now started a literature search to help answer this question about the need for such low salinities which probably favor the over production of underwater vegetation. Perhaps the data I collected, though seemingly high, will add to our knowledge about the "spring bloom" time of year in Oyster Pond.
By Robert Livingstone IIITo Page Four of The Watershed v7 n2
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