HomeMy WebLinkAboutNOIShellfish Survey
222 Pleasant Street
Yarmouth, Massachusetts
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SHELLFISH SURVEY DESCRIPTION
1.0 INTRODUCTION
On January 19th, 2022, Paul Mancuso and Marc Smith, Wetland Scientists of BSC Group
(BSC) conducted a shellfish survey from MHW into Land Under the Ocean of the Bass River
in Yarmouth, MA (the Site). The purpose of the survey was to evaluate shellfish habitat,
shellfish species, and shellfish population density within the area of an existing pier, ramp,
and floats within the Bass River. This shellfish survey accompanies a Notice of Intent
application (by Cape Cod Engineering) to replace in kind the existing pier at 222 Pleasant
Street, Yarmouth, MA (the Site).
2.0 SITE DESCRIPTION
The Bass River is a tidal river that drains into Nantucket Sound. The river is lined mostly by
single-family homes. The residence at 222 Pleasant Street is abutted by single-family homes to
the north, east, and west with the Bass River to the south. The following resource areas are
located onsite:
• Land Under the Ocean
• Land Containing Shellfish
• Salt Marsh
• Coastal Bank
• Land Subject to Coastal Storm Flowage (LSCSF)
3.0 SHELLFISH INVENTORY
In order to evaluate existing shellfish habitat at the site, BSC conducted a shellfish survey from
the Mean Highwater (MHW) to approximately -4 below Mean Low Water (MLW). The weather
during the survey was clear skies with temperatures around 27F. The survey commenced just
after low tide. In order to sample for shellfish within the project area, 3’ x 3’ survey plots were
excavated to search for existing shellfish. A total of 8 plots were surveyed along two transects
that were located 10’ off each side of the existing pier. Each survey plot was spaced 20’ apart
along the transects starting at the MHW line and working until a depth of -4 was reached.
Transect 1 – Located 10 feet to the west of existing pier.
Transect 2 – Located 10 feet to the east of existing pier.
Typically, plots would extend at least 30 feet beyond the farthest float, ramp, or other structure
associated with an existing or proposed pier/dock. However, after a depth of -4’ the ground is so
mucky it became unsafe to continue out any further. Each plot was excavated to sample for
shellfish using a standard Clam Rake and/or Quahog Rake. Each shellfish observed in the plot
was recorded then placed back into the plot from which it came from. Plot 1 on transect 1 was
located within an area of salt marsh so it was not excavated.
Shellfish Survey
222 Pleasant Street
Yarmouth, Massachusetts
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Figure 1: Showing approximate location of Transects for the shellfish survey at 222 Pleasant
Street. “T” stands for Transect.
Shellfish Survey
222 Pleasant Street
Yarmouth, Massachusetts
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The table below identifies the shellfish discovered within the plots along the 2 Transects:
Table 1 – Shellfish Inventory
Plot – Description Shellfish Substrate and Other
Observations
Transect 1 – 10’ West of Existing Pier
MHW Ribbed mussels, 2 Oysters Salt marsh – Spartina alterniflora
14’ seaward of MHW 0 shellfish Sandy, with rock
28’ seaward of MHW 0 shellfish Sandy, with rock
42’ seaward of MHW 0 shellfish Sandy, with rock
Transect 2 – 10’ East of Existing Pier
MHW 0 shellfish Sandy
14’ seaward of MHW 1 soft shell clam Sandy
28’ seaward of MHW 1 soft shell clam Sandy
42’ seaward of MHW 0 shellfish Sandy
TOTAL NUMBER OF OBSERVATION PLOTS = 8
TOTAL NUMBER OF BAY SCALLOPS = 0
TOTAL NUMBER OF RIBBED MUSSELS = Mussel Beds in Salt Marsh
TOTAL NUMBER OF OYSTERS = 2
TOTAL NUMBER OF QUAHOGS = 0
TOTAL NUMBER OF SOFT-SHELL CLAMS = 2
TOTAL NUMBER OF RAZOR CLAMS= 0
It should be noted that while only two soft shell clams and no quahogs were found within the
observation plots, clappers (empty shells) of both species were observed within the salt marsh
grasses to the west of the existing pier. This suggests that there is some presence of quahogs in
the area, just not likely a dense population. The salt marsh contained a dense population of
ribbed mussels. BSC also noted the presence of multiple species of algae; specifically, rockweed
(Fucus vesiculosus), green algae, and red algae.
4.0 TEMPORARY IMPACTS
Proposed work related to replacing the existing pier in kind would have minor impacts on the
intertidal area and Land Under the Ocean, and overall would have very limited impacts on
shellfish due to the low population density and through the observance of appropriate seasonal
timing.
The proposed work could occur during the fall/winter/early spring months when shellfish life
cycle activity is reduced. During the winter, shellfish live at increased depths in the tidal
bottom with reduced metabolism. Therefore, only minimal impacts to shellfish habitat are
expected (pilings).
Pile driving work should occur from a barge at mid to high tide to prevent the barge from
running aground.
If necessary, existing shellfish could be dug and relocated from the site. However, based on
this shellfish survey this should not be necessary since a small population of shellfish were
located near the work area.
Shellfish Survey
222 Pleasant Street
Yarmouth, Massachusetts
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5.0 SUMMARY
BSC’s shellfish survey identified the following:
Two individual soft-shell clams (Mya arenaria) and two eastern oysters (Crassostrea
virginica) were found within the 8 shellfish plots surveyed. No living quahogs were
found within the survey area.
Healthy salt marsh populated with ribbed mussels is located along the western edge of the
existing pier.
Replacing the existing pier in kind will not cause significant impacts to shellfish in the
area.
Photo 1: View of the existing pier at 222 Pleasant Street in Yarmouth and one of the
excavated survey plots.Facing west
Photo 2: View of ribbed mussels beds located within the salt marsh grass to the west of the
existing pier.
Site Photographs
Shellfish Survey
222 Pleasant Street, Yarmouth
1/19/2022
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