Making Meaning at Tidmarsh

Seven years post restoration, 51 people from 21 organizations assembled at Mass Audubon's Tidmarsh Wildlife Sanctuary to walk, explore, and learn how this wetland restoration has responded to the restoration intervention. The goal of the day was to learn together about the process of recovery at Tidmarsh, and collect insights that can be applied to other wetland restorations of cranberry farmland.

Stop 1: Before/After

Restoration Actions

• Remove large earthen dam + 2 concrete spillways
• Encourage natural recovery of channel and wetlands in former large impoundment
• Fill existing main channel and ditches (lateral and perimeter); reconstruct main channel
• Smooth upland – wetland transitions
• Plant AWC (8,000) and other perennials/trees/shrubs (30,000)
• Roughen/uncompact bog surface
• Remove sand in select locations (shallow pond NE corner)

Design

Expectations

• Growing platform will be wet
• Growing platform will host a diversity of habitats and wetland plants, largely from the seedbank.
• Area will transition through succession to a forested wetland (Nick Nelson, InterFluve)

Concerns

• Temperature of steam channel: cool channel important for river herring and sea trout. (Steve Hurley)

Observations collected from all participants

• “No longer looks like a cranberry bog, wet, natural revegetation, not a lot of invasives” - Travis
• Good amount of habitat diversity.
• Growing surface is wet, does not look like a cranberry bog.
• Slow moving stream, full to bank, sinuous.
• Stream smelly = biofoul; some algae accumulation especially around pieces of large wood and at exit from former reservoir.
• Stream bottom quite solid
•  Stream temp refreshingly cool.
• Two reported measurements possibly one closer to bank – 60.8° F (16° C) and 73°F (22.77° C); air temperature: 32°(89.6°F)
• Stream needs more shade.
• Stream seems to be processing nutrients. Algae natural.
• Ground water level 5-10 cm below surface year-round based on data from piezometers. (Research - Christine)
• Microtopography: remnant sand near top of mound; a lot of organics below.
• ·Microbes in soil are similar to a natural wetland. (Research - Jason)
• Changes to ph of soils observed over time is indicative of a natural wetland. (Research - Kate)
• Natural revegetation from seedbank is diverse: black willow, buttonbush, spatulate-leaved sundews, cattails, cranberry, various rushes, steeple bush, New York ironweed, Joe pieweed, boneset, wooly grass (dominant), swamp milkweed, poison ivy. (a list of plants identified over the day is attached)
• Pitcher plants are reproducing.
• Significant areas of sphagnum (1m x 1m s 15-25 cm deep) and polytrichtum cover.  
• AWC look healthy; some are over 12’; many have seed cones.
• Some baby AWC here and there but not the hundreds we saw at Eel River in year 7.
• AWC seed germinates best in the presence of a nurse medium such as sphagnum and/or polytrichtum. (Research - Glorianna)
• Main invasives: phragmites, grey (European) willow, purple loosestrife
• Reptile and amphibian diversity: painted turtle, snapping turtles, pickerel frogs, ribbon snake, red-eared slider. (Research: Joe Pervier)
• Dragonflies, bees, monarch butterfly, firefly.
• No mosquitoes during the day
• Song sparrows.
• Visitor experience/Education:many potential access points.
• Visitor experience/Education: walking along path (low impact) one experiences patch habitat/diversity.
• Visitor experience/education: GIS map with layers of LO data would be great for a complex site like this.

Recommendations

• Treat invasives before active restoration; they are very hard to control after restoration. (Gene)
• These sites present a gold mine for future studies (Kate)

Photo credits: top down, L to Rt: Beattie, LO, Beattie, Cohn, LO, LO, Mayton, Hatch.

Continue onto stop 2