The Nature Conservancy

Prepared by: Kim Lodge, Jordan Pares-Kane, Gregg Sargis; Condensed by Dave Scudder

Background – Sodus Creek East and West

The
Southern Sodus Wetland of the Lakeshore Marsh Wildlife Management
Area, a 6,179-acre complex, is one of only a few remaining coastal
wetland complexes in the Lake Ontario basin. This wetland provides
significant wildlife habitat, helps mitigate flooding and reduces
nutrient inputs to Sodus Bay, as well as provides numerous
recreational opportunities. The wetlands are critically important
spawning areas for recreationally significant fish species. The
wetlands also remain a regionally important waterfowl and marsh
nesting bird concentration area.

Wildlife
that inhabit these coastal wetlands depend on a diverse system, where
dominant plants such as cattails are interspersed with open water
areas, maintained by natural fluctuations in water levels and the
habitat shaping activities of muskrats and beaver. Restoration
projects in these coastal marsh habitats have been and will continue
to be the focus for enhancing wetland function and condition for a
suite of fish and bird species.

In
2016, The Nature Conservancy partnered with the New York State
Department of Environmental Conservation (NYS DEC), the Wayne County
Soil and Water Conservation District (SWCD), Save Our Sodus (SOS),
SUNY Environmental Science and Forestry (ESF), and the Finger Lakes –
Partnership for Regional Invasive Species Management (FL-PRISM) to
increase access to critical fish spawning and bird nesting habitat
significantly degraded by cattail dominance. This was accomplished
through the construction of backwater potholes, making stream channel
improvements, and conducting invasive species management and control.
During March of 2018, construction began by using a specialized marsh
sensitive excavator to construct at least 2 acres of backwater
potholes, with deep water portions constructed to prevent the
reestablishment of cattails (Figure 1); 11 out of the 14 proposed
potholes are currently complete.

In
the summers of 2017 and 2018, response monitoring projects were
carried out to assess the success of the restoration in meeting
project objectives and to compare data before and after construction.
Data collection included fish, bird, and vegetation surveys, water
quality, local culvert assessments to determine their usability for
fish passage, and mapping the sizes of each constructed pothole.

In
the end, over 115 acres of coastal wetlands were estimated to be
restored and enhanced, by reconnecting access from the bay to spring
fish spawning sites, and nesting and feeding areas for waterfowl and
marsh nesting birds.


Figure 1:
Southern Sodus backwater pothole design

Culvert Assessment:

In 2018, we conducted an assessment of 13 culverts within the Sodus Bay watershed following protocol provided by the Great Lakes Road Stream Crossing Inventory, which included gathering data on culvert type, length, height, etc. In terms of accessibility, as fish are attempting to travel upstream, culverts should not be raised more than 1 ft in height. At some locations, we found that the outlet flowed over a waterfall or raised culvert so fish may not be able to make it to upstream breeding areas.

Invasive Species Removal:

The
main invasive species of focus was the water chestnut, a rooted
submerged aquatic plant, which grows quickly, forms dense mats, and
outcompetes native species. Water chestnut impedes boat travel and
recreation activity, and prevents sunlight from reaching other
aquatic vegetation. As part of our partnership with NYS DEC, SWCD,
and FL-PRISM, we organized a number of volunteer events throughout
the summers of 2017 and 2018 to remove water chestnut from the
Southern Sodus Bay marsh area.


Water chestnut image from thebeatnews.org

Observations/Lessons Learned

The
majority of the pike caught in 2018 was in the In Between pothole.
This pothole had a number of small pockets along the cattail borders
which may have provided good spaces for pike to lay their eggs in a
slightly protected area. This may be good to note for future pothole
construction or amending other existing areas; cutting out small
portions of cattail benefit pike during spawning.

Since
pike are moderate to weak swimmers, it is important to note that the
culverts we investigated that are connected to Sodus Bay, East Bay,
and Port Bay appear to have sufficient water depths and low flow
velocities necessary for pike passage through them.

The
efforts to remove and control water chestnut is also an important
project to continue. It may be beneficial to start organizing pulls
in both June and July, because by the end of July the plants were
already fully mature and their seeds released.

Looking forward, we intend to complete the original wetland design by completing potholes 11 and 12 and adding 4 new potholes . We are also working with the NYS DEC to construct additional potholes northeast of the wetland area, across from Le Roy Island. See the graphic below.


Possible locations for new potholes in the southern marsh.