Habitats

Kings Island forest - Patrick Comins.

Biologically diverse habitats that support native plants and animals are critical to the health of the Connecticut River ecosystem. As development increases in the watershed, the protected lands within the Silvio O. Conte National Fish and Wildlife Refuge become crucial in providing natural habitats, some of which are rare in the watershed, to support the animal communities that rely upon them.

 

Low Elevation Spruce-fir Forest | Floodplain Forests | Riverine 

There is an amazing diversity of habitats in the watershed; from the low-elevation spruce-fir forests at the source of the Connecticut River to the tidal wetlands at the mouth of the river. Management of refuge habitats is important in maintaining healthy wildlife populations where hundreds of species and over 2 million people coexist.

Low Elevation Spruce-fir Forest

Low elevation spruce-fir forests are found in the northern portions of the watershed, where cold temperatures create the proper conditions for this forest community to survive. Low elevation spruce-fir forests occur in cold pockets along flat to gentle slopes, plateaus, and river valleys at elevations under 2,200 feet. Red spruce and balsam fir tend to dominate this forest community, though white pine is part of the canopy on drier sites, and black spruce is common on wetter soils. Other tree species such as white spruce, red maple, aspen, yellow and paper birch, and black cherry may also be present. Common shrubs include mountain holly, wild raisin, sheep laurel, leather leaf and Labrador tea, and characteristic herbs include wood fern, goldthread, bunchberry, bluebead lily, and Canada mayflower. Moss and liverworts often dominate the groundcover.

Management Challenges 

Spruce and fir are valued as timber, and have been heavily harvested for over 100 years. Harvesting techniques have created spruce-fir forests that often lack important habitat features such as standing dead trees, decaying logs on the forest floor, and large trees in the canopy. These features provide habitat for wildlife such as woodpeckers and black bears, and add nutrients to the forest floor. In some areas, harvesting techniques have created conditions that favor hardwood species. Spruce and fir will often re-colonize the site, but it will take many years (70+ years) before they become dominate, and wildlife species that depend on spruce-fir forests will be impacted.

Birds: Swainson’s thrush, yellow-bellied flycatcher, red-breasted nuthatch, ruby-crowned kinglet, blackburnian warbler, rusty blackbird, Canada warbler, blackpoll warbler, bay-breasted warbler, boreal chickadee, black-backed woodpecker, gray jay, spruce grouse.

Mammals: Canada lynx, moose, red squirrel, fisher, porcupine, red fox, white-tailed deer.

Divisions: Pondicherry Division, Nulhegan Basin Division, Blueberry Swamp Division.

Floodplain Forests

Floodplains are flat areas adjacent to large bodies of water, such as rivers, where sediments are deposited and eroded by slow moving floodwaters. Annual spring snowmelt and rains are often the cause for the Connecticut River and tributaries to overflow their banks. Species occurrence within floodplain forests in the Connecticut River watershed are influenced by this seasonal flooding. Silver maple tends to dominate these forests. Eastern cottonwood, slippery elm, boxelder and black willow may also be present. Ostrich fern or sensitive fern dominate the ground cover, often mixed with wood nettle, and/or false nettle, and marsh fern, wild rye, and wild cucumber. Historically, American elm was an important constituent. These riverside forests provide critical nursery habitats (e.g., shade, cover) for some fish and important migratory stopover habitat for many migrating songbirds. Vernal pools and back-chanel swamps that hold water after spring flooding may provide important breeding habitat for amphibians.

Management Challenges 

Although active flooding has limited development, many of these floodplain forests have been converted to agriculture, and others have been altered by a lack of seasonal flooding. Flood control dams in the upper watershed have changed the flooding regime, reducing the frequency and intensity of large scouring events. Historic floodplains have been cut off by elevated railroad grades that follow the river course and/or by the dikes/levees built around urban areas (e.g., Northampton MA, West Springfield MA). Roads are commonly located adjacent to rivers/streams. In both situations, site hydrology may be altered affecting floodplain plants. Invasive plants pose serious threats to floodplain habitats because they often are well adapted to disturbed areas.

Birds: veery, yellow warbler, eastern wood pewee, great crested flycatcher, American woodcock, American black duck, wood duck, northern oriole.

Mammals: bats, beaver, river otter, mink, muskrat.

Amphibians: American toad, wood frog, spring peeper, spotted salamander

Divisions: Mill River Division.

Riverine

The Connecticut River flows 410 miles from the spruce-fir forests of northern New Hampshire to saltmarsh and beaches at Long Island Sound. The watershed includes more than 20,000 miles of tributaries and streams providing diverse habitat for numerous aquatic species.

The Upper Connecticut River watershed is mountainous, steep, and rugged. Streams, brooks, and rivers are fresh, cold and often descend quickly through this northern terrain, being fed through rainfall, snowmelt, and groundwater. Cold water species, such as brook trout and mussels, including brook floater and dwarf wedgemussel occur in these habitat conditions. The lower portion of the river is warmer and strongly influenced by the saltwater of Long Island Sound. Atlantic salmon, American shad, blueback herring, and American eel migrate and spawn in the lower coves and tributaries of the river.

Management Challenges 

There are 38 flood control projects operated by the U.S. Army Corps of Engineers and almost 1,000 small dams on the tributaries that were built to power mills in the 1700s and 1800s. Flow, especially during low-flow periods, are highly regulated and restricted by dams in the watershed. Maintaining a natural flow regime in such a highly controlled river system presents a tremendous challenge. In addition poorly designed road crossings (e.g., undersized culverts) block fish from reaching available habitat. Industrial effluents, cooling water discharges, and other pollutants are also impacting aquatic resources in the Connecticut River watershed.

Fish: Atlantic salmon, brook trout, American shad, American eel, shortnose sturgeon, blueback herring, alewife.

Mussels: Brook floater, dwarf wedgemussel.