Natural Resource Inventory and Assessment - Town of Guilford

APPENDIX B-4
Quick Facts About Long Island Sound
Long Island Sound (LIS) is 110 miles long and 21 miles wide at its widest point. The linear shoreline of
CT is 130 miles, and the coastline is estimated to be 618 miles (includes coves and embayments) with 95
miles of publicly owned beaches
LIS covers 1,300 square miles and its average depth is 65 feet and its tidal range is 2.7 feet (east) and 7.4
feet (west). The Race is 350 feet deep and twice a day, 25 billion gallons of water rush into the Sound
Salinity averages 28 parts per thousand (ppt) representing 2 billion tons of dissolved salt
Because of the teeming life and great variety of dissolved materials in LIS, light penetration is often less
than 30 feet below the surface (compare more than 200 feet in the Sargasso Sea)
LIS (and all oceans) soaks up carbon dioxide from the atmosphere via white caps and plumes
Long Island Sound Watershed
Watershed extends to Canada and covers 15,820 square miles. It is inhabited by 14.6 million people and
it is estimated that 1 in 10 Americans live within 50 miles of LIS
90 percent of freshwater entering LIS comes from the Housatonic, Connecticut and Thames Rivers and
any pollutants entering this vast watershed can ultimately harm the Sound
Living Resources
As of 1997, the Sound leaded the nation with 42,000 acres cultivated as oyster farms with an annual
harvest of 700,000 bushels
Of the 60 million eggs produced by an adult female oyster in the wild, only 42,000 survive the larval stage
to settle on the bottom. Of these, only about 13 survive to become adults
The American eel is catadromous, lives in freshwater, and spawns in the Sargasso Sea. The female lays 10-
20 million eggs and the larvae swim 1,000 miles back to LIS and the rivers
LIS once had 50,000 acres of salt marsh – less than half remains today
Estuaries in general
Due to the mixing of nutrients from land and sea, estuaries are among the most productive natural
systems on earth, producing more food per acre than the richest mid-western farmland
There are over 130 estuaries throughout the US of which 28 are designated as a “Nationally Significant
Estuary” through the National Estuary Program (NEP). LIS is one of the first to receive this distinction.
Over 75 percent of commercially and recreationally important fisheries depend on estuaries
Over 45 percent of all endangered and threatened species rely on estuarine and coastal waters, as do 75
percent of all endangered and threatened birds and mammals and 30 percent of all wintering waterfowl
Sources: various
Natural Resource Inventory and Assessment Town of Guilford, CT B-4
Appendix