Block Island Ecological Geography

Block Island, created by glaciers over 10,000 years ago, is home to over 40 rare and/or endangered species, making it an extremely ecologically significant area within the whole northeast. Over 43% of the island is protected by works of the Block Island Nature Conservancy and individuals within the community.

The island’s special geological makeup includes 6 specific and different terrain. The first, are the island’s iconic coastal bluffs. Spreading along the east and south shores, the bluffs reach over 160 feet elevation in areas such as the Mohegan Bluffs and are made of mostly gravel. Next, are the islands beaches, with a coastline extending 29 miles with the exception of the Great Salt Pond. Yearly, along the coastlines, land has been eroding at an estimated 4.9 feet. Another type of terrain, are the island’s low-lying sand dunes, seen mainly around the edges of the Great Salt Pond, lying between the northern and southern divisions of the island. Sand dunes prevent flooding and erosion of land. Equally important to the dunes themselves is the vegetation that grows throughout these areas, anchoring in sediment and allowing continuous growth. Resulting vegetation loss along sand dunes from trampling, storms, etc. causes sand and sediment from the beaches to move along inner lands, leading to soil degradation and stable land loss. The island also has large stretches of morainal grasslands. Moraine, is left behind materials from glacier ice that lie beneath rock and other areas affected by recent fluvial activity, when sediment is transported along channels by force of water- activity.

Lastly, are the islands salt and freshwater ponds; The Great Salt Pond being the largest on the island and over 365 total freshwater ponds and wetland ecosystems from natural springs.

In addition, a little less than one third of Block Island’s land surface is used for farming, while throughout its coasts are oyster and other shell fish farms.