The Effect of Human Actives on Long Island Sound
Humans have inhabited the shores of Long Island Sound for thousands of years. Before European settlement, many Native American tribes lived along the Sound. Now more than 20 million people live within 50 miles of its shores. The increased pressure of human actives, especially within the last century, has negatively affected the Sound's ecosystem. By learning about our effects on the Sound and how we can minimize them, we can better protect its unique ecology.
The water of the Sound looks very clean. What you can't see are the pollutants that can harm or kill marine life, occasionally make the water unsafe for swimming, and make some types of seafood unhealthy for us to eat in large amounts.
Rain and snow collect airborne particles of mercury and deposit them in the Sound. Some mercury enters the food chain and eventually builds up in the tissue of fish, making certain species unsafe for high-risk populations (young children, pregnant or nursing mothers) to eat. When you see water into street drains, it's ultimately headed for the Sound - carrying with it any contaminants it has picked up along the way. In addition, toxins and bacteria from sources like failing septic systems, farm waste runoff, and Canada geese droppings can make us sick
if we swallow polluted water while swimming or eat shellfish harvested from unapproved waters.
Nitrogen from fertilizers and sewage treatment plants stimulate huge populations of phytoplankton. After the plankton die, the process of decay uses up much of the oxygen in the water, creating a condition called hypoxia. Fish need oxygen just like we do, so they swim away from hypoxic zones. Some animals, like starfish, can't move as quickly and may die form lower levels of oxygen.
Reducing pollution requires efforts from residents. Make sure your septic system is working and maintained properly, clean up after your pets, and don't allow anything other than stormwater to flow into neighborhood storm drains, that means keeping your car tuned up and leak free! Take your can to a car wash, which recycles and filters water, or wash it on the lawn where the grass can absorb soap and pollutants.
Before residents realized the value of tidal marshes, many such areas were lost to development. Colonists drained marshes to graze animals and harvest the salt marsh hay.
Other marshes were filled in for the construction of the shoreline railroad and, laterInterstate-95. During the 1930s, almost all of Connecticut's remaining marshes were drained to control mosquitoes, which carried malaria. As marshes disappeared, the Sound began to lose an important filtration system that removed pollutants and excess nutrients from the water. Young fish and other animals lost critical nurseries and foraging habitats. With fewer marshes to act as buffer zones, strong coastal storms are more likely to batter homes and businesses.
Along with other organizations, the Connecticut Department of Environmental Protection (DEP) has embarked on an ambitious march restoration plan. As of 2008, tidal flow to nearby 2,025 acres of marshland has been restored. This allows native plants and animals to thrive once again in the marshes, and help protect coastal communities from flooding and other storm damage.
One early New England settler described seeing alewives "in such multitudes as is almost incredible, pressing up such shallow waters as will scare permit them to swim." Alewives, shad, and other migratory fish called diadromous fish, live in both fresh water and salt water, and migrate back and forth to spawn. During the Industrial Revolution dams built on many streams to harness hydroelectric power blocked the migration of diadromous fish. Now most of these species, including American shad, alewives, and American eels, persist only in low numbers. Some, like Atlantic salmon, have vanished from the Sound.
The Connecticut DEP has joined with other government agencies and conservation groups to restore migratory species to their historic range within watersheds across the state through dam removal, fishway construction, fish stocking, fish transplantation, regulation of fisheries and habitat protection, conservation, and restoration.
Many of Long Island Sound's fish and shellfish taste delicious and are healthy sources of protein. Commercial fishermen and recreational anglers harvest flounder, lobster, and many other types of seafood from the Sound. The populations of many species are depleted due to poor water quality, disease, and past overfishing. Today the Connecticut DEP works with commercial and recreational fishermen to implement conservation measures and enforce strict quotas to help these populations recover. The DEP also conducts semi-annual trawl surveys to monitor fish population.
Turn over almost any rock in the intertidal zone and you will find Asian shore crabs. Native to Asia waters, this crab arrived on our shores about 15 years ago, most likely in the ballast water of large oceangoing ships. Once here, they adapted so well the they began to crowd out some native crab species, such as the black-fingered mud crab. Many government, academic, and non-profit organizations are working hard to remove certain invasive species, restore native populations and educate the public about how to prevent future introductions.
We've already started to see the effects of global warming in Connecticut. Warmer water was partly responsible for a major lobster die-off in 1999. If the water continues to ware, lobster and other species that prefer colder water may disappear from the Sound as species that prefer warmer water move in.
As Earth's temperature increases, glaciers are melting faster. This water flows into the ocean, which are already beginning to rise in some parts of world. If warming continues, scientist expect seal leaves in Connecticut to rise about a tenth of an inch each year. After many years the spot where you're standing could be underwater.
What can you Do?
Thanks to many organizations and people, including those mentioned above, the Sound is well on its way to returning to the healthy ecosystem it once was. But it takes all of us, and we hope you choose to be part of the solution. Mark sure any trash you bring makes it into a trash can or goes home with you (recycle when possible)!, respect the creatures that make their homes here and think about how the choices you make in your everyday life may indirectly influences the fate of the Long Island Sound.
Stormwater drains often empty directly into the Sound.
The fish ladder in Branford, Connecticut, allows migrating fish through the dam. The grate covers a series of water-filled steps that the fish can jump