Each island has its own natural environment, evokes a distinct mood, and tells its story of the past. Yet each shares the unusual quality of being both a place apart and a facet of the city's maritime character.
Together these 34 islands and peninsulas encompass a broad swath of the Boston area's cultural and natural history. American Indians sought out the islands for food, ritual, and recreation long before Europeans arrived.
Since the s newcomers have used them for everything from fishing settlements to harbor defense sites. Today, after a determined partnership effort to restore the health of the harbor and reclaim the islands from exploitation, they abound with things to do, ways to learn, and places to explore.
These Boston Harbor Islands, scattered across the expansive, bustling harbor they help to define, offer historical landscapes where structures from the s can pull you back to an earlier time.
The members have a long record of protection of natural and cultural resources. The Partnership also works with educational and for-profit groups to promote citizen stewardship of the islands. When you look over Boston Harbor, you're seeing a drowned drumlin field, hills built during the last ice age and later covered by rising seas. Those whose tops remained above water are the Boston Harbor Islands. The harbor's great tidal swings and moderate salinity create environments hosting an array of land and marine wildlife: rabbits, raccoons, and other small mammals on the islands, harbor seals resting on the rocks of the outer islands, dozens of bird species perched on pilings, wheeling in the air, or feeding in the salt marshes.
For millennia Northeast coastal Indians fished, farmed, and hunted on the islands, and European settlers used them for much the same purposes. The large natural harbor and New England's transportation network have made Boston a thriving seaport since the s.
The port has its share of sea tales, as ships plying the harbor's sealanes attracted pirates. Boston has also been a port of entry for early settlers and later immigrants seeking a better life in a new world. These islands have historically been places where society has set apart unwelcome institutions and people on the margins.
The connecting land between drumlins is known as a tombolo. You can see four of those drumlins against the Boston skyline. Gallups Island is the drumlin on the far right, behind Peddocks.
An eroded bluff on Lovells Island. Here you can see the mixture of sand, clay, and gravel that make up the glacial deposits. You can also see how sharply the edge of the drumlin drops off. This picture shows a closeup of the same bluff. Note that the layers at the top, about a foot deep, represent the soil that has formed after the drumlin was formed. This rock, known as "Lover's Rock", is a glacial erratic , a large boulder that was moved from far away by the advancing glaciers, and then deposited on top of the drumlin as the glacier retreated.
This rock is granite, which was initially formed at least miles away, and perhaps even farther. For another dramatic example of a glacial erratic, check out "Big House Rock" in Weymouth. There is evidence that Native Americans inhabited the Boston Harbor Islands area as early as 5, years ago. At that time, the islands were not islands. Recall from above that because of lower sea levels, the harbor islands were a set of hills drumlins in the midst of a grassy plain.
The early native people who inhabited this area used the hills and the grassy plains between them as well as the coast now under water much farther East than today. Prime and Unique Farmlands The U. Department of Agriculture defines prime farmland as the land that is best suited for food, feed, forage, fiber, and oilseed crops; unique farmland produces specialty crops such as fruit, vegetables, and nuts.
Five soils classified as prime or unique farmland types occur within Boston Harbor Islands: Canton fine sandy loam, Merrimac fine sandy loam, Newport silt loam, Pittstown silt loam, and Sudbury fine sandy loam. There are no historically farmed areas still in active agricultural use.
Of the islands within the park, Thompson has the greatest percentage and variety of prime agricultural soils. About three-quarters of the island is composed of a patchwork of all five prime agricultural soil types.
About two-thirds of Long Island and about half of Grape Island are covered with both Newport silt loam and Pittstown silt loam.
The construction of the sewage treatment plant on Deer Island and the deposit of fill on Spectacle Island have since dramatically altered the soil content on those islands. Groundwater All islands with soil provide a receptacle for some groundwater.
Because there is a shallow, relatively lowvolume water table in the highly permeable soils on all of the drumlins, the groundwater is vulnerable to contamination from failed septic systems, chemical spills, leaching dumpsites, fuel spills, and saltwater intrusion.
Boston Harbor is part of the Boston Basin, a topographic lowland underlain by sedimentary layers deposited at the end of the Precambrian time.
Where bedrock is exposed Calf Island, the Brewsters, and small islands near Hingham , it is a shaly to slaty formation called Cambridge Argillite which was deposited on the muddy floor of an ocean dating back some million years.
A few eskers can also be seen, which are thin, meandering lines of low hills that are formed as rivers of glacial melt water flow beneath the ice and deposit sediment. A kettle pond is a deep depression resulting from a block of glacial ice that was surrounded by sediments then subsequently melted and filled by water is thought to be the origin of the large southern salt marsh on Thompson Island, Finally, slickensides and similar features are seen on exposed bedrock, which are striations and linear scratch-marks that mark glacial flow.
Boston experienced several periods of glaciation, so it is no wonder that many of the geologic features here continue to tell the story of these incredibly large areas of moving ice. Explore This Park. Info Alerts Maps Calendar. Alerts In Effect Dismiss. Dismiss View all alerts.
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