Photos of the Long Island Sound

Research & Monitoring

Status & Trends

LISS Ecosystem Targets and Supporting Indicators

Clean Waters and Healthy Watersheds

Clean Water and Healthy Watershed ecosystem targets track progress towards attaining the goal of improving water quality by reducing contaminant and nutrient loads from the land and the waters impacting Long Island Sound.

Extent of Hypoxia

Measurably reduce the area of hypoxia in Long Island Sound from pre-2000 Dissolved Oxygen TMDL averages to increase attainment of water quality standards for dissolved oxygen by 2035, as measured by the five-year running average size of the zone. View Ecosystem Target

Nitrogen Loading

Attain wastewater treatment facility nitrogen loading at the recommended 2000 Dissolved Oxygen Total Maximum Daily Load allocation level by 2017 and maintain the loading cap. Have all practices and measures installed to attain the allocations for stormwater and nonpoint source inputs from the entire watershed by 2025. View Ecosystem Target

Water Clarity

Improve water clarity by 2035 to support healthy eelgrass communities and attainment of the eelgrass extent target. View Ecosystem Target

Impervious Cover

Through green infrastructure, low impact development, and stormwater disconnections, decrease by 10 percent the effective area of impervious cover in the Connecticut and New York portions of the watershed by 2035 relative to 2010 baseline. View Ecosystem Target

Riparian Buffer Extent

Increase the percent area of natural vegetation within 300 feet of any stream or lake in the Connecticut and New York portions of the Long Island Sound watershed to 75% (1,030 square miles of natural vegetation) by 2035 from 2010 baseline of 65%. View Ecosystem Target

Approved Shellfish Areas

Upgrade 5% of the acreage currently restricted or closed for shellfishing by 2035 from a 2014 baseline. View Ecosystem Target

Sediment Quality Improvement

Reduce the area of impaired sediment in Long Island Sound by 20% by 2035 from 2006 baseline. View Ecosystem Target

Industrial Chemical Discharges (TRI data – Total LIS watershed and CT and NY portion of watershed)

This indicator compiles the total amount of discharges of toxic chemicals manufactured and used at industrial facilities that are released into the Sound either by air or by water. View Indicator

Duration of Hypoxia

Hypoxia is a condition that occurs in bodies of water as dissolved oxygen concentrations decrease to levels where organisms become physically stressed and ultimately cannot survive. Duration of hypoxia refers to the number of days in a year during which hypoxia was observed in Long Island Sound View Indicator

Severely Hypoxic and Anoxic Areas

Hypoxia is a condition that occurs in bodies of water as dissolved oxygen concentrations decrease to levels where organisms become physically stressed and ultimately cannot survive. The area of hypoxia in Long Island Sound refers to the number of square miles in which dissolved oxygen concentrations were less than 3 mg/L over the course of a single year. Severely hypoxic areas are less than 2 mg/L and anoxic areas are less than 1 mg/L. View Indicator

Water Quality Index

The water quality index is a calculation that combines several water quality measurements to rate overall water quality in Long Island Sound on an annual basis. View Indicator

Thriving Habitats and Abundant Wildlife

Thriving Habitats and Abundant Wildlife ecosystem targets track progress towards attaining the goal of restoring and protecting the Sound's ecological balance in a healthy, productive, and resilient state to benefit both people and the natural environment.

Coastal Habitat Extent

Restore an additional 350 acres of coastal habitat by 2020 from a 2014 baseline View Ecosystem Target

Eelgrass Extent

Restore and maintain an additional 2,000 acres of eelgrass by 2035 from a 2012 baseline of 2,061. View Ecosystem Target

Tidal Wetland Extent

Restore an additional 515 acres of tidal wetlands by 2035 from a 2014 baseline. View Ecosystem Target

River Miles Restored for Fish Passage

Open 200 additional miles of fish riverine migratory corridors in the Connecticut and New York portions of the watershed by 2035 from a 2014 baseline of 307.76 miles. View Ecosystem Target

Shellfish Harvested

Increase the harvest of oysters, clams, and scallops in the Sound through a combination of habitat management and shellfish aquaculture. View Ecosystem Target

Habitat Connectivity

Increase connectivity of coastal habitat by 2035 by restoring and/or protecting habitat patches that increase biodiversity and support migratory pathways. View Ecosystem Target

Protected Open Space

Conserve an additional 4,000 acres of Connecticut land and 3,000 acres of New York land within the Long Island Sound coastal boundary by 2035, while maintaining or increasing the total area of protected land. View Ecosystem Target

Changes in Forest Cover in CT & NY

This indicator tracks an important habitat in protecting riparian buffers and coastal ecoystems. View Indicator

Index of Anadromous Fish Runs

These counts of river herring and shad in Long Island Sound tributaries indicate the quality of upstream habitat that has been opened up as a result of completed fishway projects. View Indicator

Herring Runs at Streams with Upstream Planned Fishway Projects

These counts of river herring and shad in Long Island Sound tributaries indicate the quality of upstream habitat that has been opened up as a result of completed fishway projects. View Indicator

Horseshoe Crab Abundance

This indicator shows the abundance of Horseshoe Crabs in Connecticut and New York. View Indicator

Lobster Abundance

Lobster has historically been an important fishery in Long Island Sound but populations have declined in recent years. This indicator is a fisheries-independent estimation of their abundance in the Sound. View Indicator

Forage Fish – Open Water/NY and CT Coastlines

The forage indices measures the productivity of small fish in the Sound, which is the basis of the food supply for larger fish, including game fish. View Indicator

Finfish Biomass Index/Species Richness

Fish biomass indicates the productivity of the Long Island Sound fishery. Species richness measures the diversity of species supported within the Sound's various habitats. View Indicator

Game Fish

The abundance of game fish is a reflection of the productivity of Long Island Sound and the effectiveness of coast-wide fishery management plans that seek to stabilize populations while maximizing harvest opportunities. View Indicator

Shad & Blueback Herring—Long Island Sound

Abundance of American shad and blueback herring, as reported in the Long Island Sound Trawl Survey. View Indicator

Least Terns

The least tern is the smallest of American terns. They are migratory birds that breed along marine and estuarine shores of the United States. Their abundance indicates the quality of coastal habitat and quantity of forage fish available for food. View Indicator

Piping Plovers

Piping plovers are small shorebirds that nest on the beaches of Long Island Sound. The abundance of breeding pairs reflects availability of beach nesting habitat and management efforts to protect nesting pairs from human intrusion, storm tides and predators. View Indicator

Sustainable and Resilient Communities

Sustainable and Resilient Communities ecosystem targets track progress towards attaining the goal of supporting vibrant, informed, and engaged communities that use, appreciate, and help protect Long Island Sound.

Waterfront Community Resiliency and Sustainability

All coastal municipalities have prepared plans for shoreline resiliency and infrastructure sustainability and resiliency by 2025, with all future development compliant with those plans by 2035. View Ecosystem Target

Harbor and Bay Navigability

Maintain all federal navigation channels in harbors and bays and manage dredged material in a cost effective and environmentally sound manner, consistent with a bi-state Dredged Material Management Plan, by 2035. View Ecosystem Target

Public Engagement and Knowledge

Increase the knowledge and engagement of the public in the protection and/or restoration of Long Island Sound. View Ecosystem Target

Public Beach Closures

Reduce by 50% the number of beaches reporting at least one closure day or the total number of beach-day closures per monitored beach due to water quality impairments by 2035 compared to a five-year rolling average from 2014. View Ecosystem Target

Marine Debris

Decrease the mass of marine debris in Long Island Sound by 2035, using as a metric a decrease from the 2013 baseline of 475 pounds of debris collected per mile during the fall International Coastal Cleanup. View Ecosystem Target

Public Access to Beaches and Waterways

Increase the number of public access points accessible by the public to the Sound and its rivers by at least 10 percent by 2035. View Ecosystem Target

Watershed Population

This indicator uses US Census data to track the population living within the Long Island Sound watershed. View Indicator

Population Within 50-mile Buffer of Long Island Sound

This indicator uses US Census data to track the population living within the Long Island Sound watershed. View Indicator

Volunteers at Coastal Cleanups

This measure indicates the efforts of volunteers to clean debris deposited on Long Island Sound beaches. View Indicator

Climate Change

Climate change indicators appear in different topic areas, and include physical, biological, chemical, and socioeconomic measures. The breadth of measures is because conditions affected by climate change such as sea level rise, temperature change, and increased ocean acidification can impact animals and plants and their habitats as well as humans throughout the region. These indicators help resource managers assess climate change’s current impacts on the the Sound, and project future trends.

Length of Growing Season

This indicator tracks the length of the growing season, which is the variation between the last frost of spring and the first frost of fall. View Indicator

Spring Freshet

The indicator tracks the time of the spring freshet (a measure of snow melt) on the Connecticut River to assess if there is a warming trend. View Indicator

Sea Level Trends for Kings Point

The Sea Level Rise indicator shows the average sea level at a given point, over a year. View Indicator

Water Temperature

Yearly seasonal temperatures from 1976-2012, measured in Niantic Bay by the Millstone Environmental Lab. View Indicator

Warm Water/Cold Water Fish Index

This indicator tracks the species composition of fish that prefer colder temperatures and those that prefer warmer temperatures. View Indicator

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