Habitats are places where plants and
animals live, feed, find shelter, and reproduce. Due to
topography and wide tidal variations characteristic of the Gulf of
Maine, Maine has the most extensive intertidal habitats (the area
between the high and low tide lines) found along the Atlantic Coast of
the United States. Casco Bay's intertidal area includes nearly
200,000 acres of clam flats. Along the bay, salt marshes,
including many small fringing marshes along the water's edge, filter
stormwater from upland developments and help moderate nutrient flow to
adjoining waters. These marshes also act as buffers during storms
and help to reduce damage from flooding.
Aproximately 150 species of waterbirds
inhabit Casco Bay and the 500 acres of rocky shore in Casco Bay provide
habitat for a wide range of species: from seaweeds, lobsters, mussels,
barnacles, and crabs to starfish and seals.
Plants, which support the food chain, are
an important part of subtidal habitats in Casco Bay. These are
submerged habitats located below the mean low-water line. One
particularly sensitive plant, eelgrass, is considered an indicator of
ecosystem health. Casco Bay has the largest and densest
concentrations of eelgrass mapped along the coast of Maine, with over
8,000 acres of beds.
Casco Bay contains 758 island, islets, and
exposed ledges at mean high tide, some of which are important habitat
for colonial nesting sea birds.
Casco Bay Rivers, Streams, and
Freshwater Wetlands
Throughout the Casco Bay watershed, there
are more than 1,356 miles of rivers and streams. Streams provide
important habitats for fish, including anadromous species (fish like
alewife and smelt that spawn in fresh water then move into salt
water). The freshwater systems provide habitat for a wide variety
of species including the bald eagle, belted kingfisher, loons, black
duck, spotted sandpiper, shad, trout, bass, perch, and pickerel as well
as mammals like muskrat, beaver, and river otter.
Impacts to Habitat
Human activity can threaten habitat in
numerous ways -- through direct loss, fragmentation, encroachment,
disturbance, diminished water quality, altered drainage patterns, and
creation of barriers. In addition, invasive non-native species
can threaten the quality of habitat by outcompeting native species for
space and resources. Global warming can impact habitat by
altering habitat characteristics (e.g., temperature, precipitation),
affecting the range of habitats available to native species, and
opening habitats to invasion from non-native organisms.
What Can be Done to Conserve Habitat?
Humans sharing the ecological community of
Casco Bay have a responsibility to conserve our natural
habitats. The Casco Bay Estuary Partnership works to
conserve habitat using a multi-pronged approach: through habitat
restoration projects (including on-the-ground field work, assessment,
mapping and inventory development); through habitat protection
(including assistance with property acquisition and conservation
easements, and mapping conserved habitat areas); and by developing
educational tools and indicators to address impacts from climate change
and invasive species.
Click here or on the Current
Projects button to the right for examples of the habitat conservation
activities that CBEP and our partner organizations are supporting.