Essential Fish Habitat (EFH) are bodies of water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

 and substrate

Substrate (marine biology)

Stream substrate is the material that rests at the bottom of a stream. There are several classification guides. One is:*Mud – silt and clay.*Sand – Particles between 0.06 and 2 mm in diameter.*Granule – Between 2 and 4 mm in diameter....

 required for fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

 spawning, breeding

Breeding

Breeding is the reproduction, that is, producing of offspring, usually animals or plants:* Breeding in the wild, the natural process of reproduction in the animal kingdom* Animal husbandry, through selected specimens such as dogs, horses, and rabbits...

, feeding, and a place they can grow to maturity. Bodies of water (freshwater

Freshwater

Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...

, estuaries

Estuary

An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....

 and saltwater systems) that fishes use as habitat have physical, chemical, and biological components and also include historical aquatic environments that fish have always used.

Important essential fish habitat

Habitat

* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...

 characteristics include sediment

Sediment

Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....

 type, type of bottoms (sand, silly and clay), structures underlying the water surface, and aquatic community structures. These habitats and environments are essential for fish and a fisheries

Fishery

Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...

 health in an ecosystem

Ecosystem

An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....

. Sediment in relation to essential fish habitat is a place where essential habitat begins; primary productivity

Productivity

Productivity is a measure of the efficiency of production. Productivity is a ratio of what is produced to what is required to produce it. Usually this ratio is in the form of an average, expressing the total output divided by the total input...

 takes place here because benthic

Benthic zone

The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos. They generally live in close relationship with the substrate bottom; many such...

 photosynthetic

Photosynthesis

Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...

 algae

Algae

Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

 provide food, nutrient

Nutrient

A nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment. They are used to build and repair tissues, regulate body processes and are converted to and used as energy...

s and help stabilize the sediment from erosion

Erosion

Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

 in aquatic environments. Erosion is also stabilized by the size of the grain size (sand

Sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...

, silt

Silt

Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. Silt may occur as a soil or as suspended sediment in a surface water body...

 and clay

Clay

Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...

). There are two main types of bottoms, hard and soft.

Bottom habitat

A study by Christensen at el. (2004) looked at three bottom types (vegetated marsh

Marsh

In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....

 edge, submerged aquatic vegetation, and shallow non-vegetated bottom) in relation to juvenile brown shrimp (Farfantepenaeus aztecus). The results from the study showed that brown shrimp selected vegetated areas in salinities 15-25 ppt and they would select vegetated areas over marsh edges when they co-occurred. Finding the areas that had the highest abundance, helped to identify essential habitat of juvenile brown shrimp.

Hard habitat

Hard bottom refers to coral reef

Coral reef

Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...

 communities, exposed areas or consolidated sediments and manmade reefs that occur in temperate, subtropical and tropical geographic locations. Hard bottoms are sometimes referred to as live rock

Live rock

Live rock is rock from the ocean that has been introduced into a saltwater aquarium. Along with live sand, it confers to the closed marine system multiple benefits desired by the saltwater aquarium hobbyist...

 or live bottom because of the living plant

Plant

Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

s and invertebra

Invertebrate

An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...

, and fish that are present, attach or border hard bottoms. These include coral

Coral

Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...

, hard coral, bryozoa

Bryozoa

The Bryozoa, also known as Ectoprocta or commonly as moss animals, are a phylum of aquatic invertebrate animals. Typically about long, they are filter feeders that sieve food particles out of the water using a retractable lophophore, a "crown" of tentacles lined with cilia...

ns, ploychaete worms, tunicate

Tunicate

Tunicates, also known as urochordates, are members of the subphylum Tunicata, previously known as Urochordata, a group of underwater saclike filter feeders with incurrent and excurrent siphons that is classified within the phylum Chordata. While most tunicates live on the ocean floor, others such...

s, a variety of fin-fishes, alga, and sponges. Areas of compacted or sheered mud and sediment are also a form of hard bottom.

Soft habitat

Around the world, soft bottom consist of unconsolidated sediment and unvegetated areas. It also has only one habitat requirement which is sediment supplied. In some regions soft bottoms are not protected even though they may be primary nursery areas, anadromous fish spawning areas, and andaromous nursery areas. Characteristics that affect soft bottom in relation to organisms that utilize them include sediment grain size, salinity

Salinity

Salinity is the saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates...

, dissolved oxygen and flow.

Magnuson-Stevens Act

In 1996, the Magnuson-Stevens Fishery Conservation and Management Act were amended to incorporate essential fish habitat and final rules were published in the Federal Register

Federal Register

The Federal Register , abbreviated FR, or sometimes Fed. Reg.) is the official journal of the federal government of the United States that contains most routine publications and public notices of government agencies...

 on December 19, 1997. The Magnuson-Stevens Act has jurisdiction over the management

Wildlife management

Wildlife management attempts to balance the needs of wildlife with the needs of people using the best available science. Wildlife management can include game keeping, wildlife conservation and pest control...

 and conservation of marine fish species. Congress has created councils to classify unfavorable impacts on fishes in relation to types of fishing gear, coastal developments and nonpoint and point source pollution

Pollution

Pollution is the introduction of contaminants into a natural environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substances or energy, such as noise, heat or light...

, as well as, evaluating how well each one is managed. Essential fish habitat still face big issues like, budget limits in research fields, lawsuit

Lawsuit

A lawsuit or "suit in law" is a civil action brought in a court of law in which a plaintiff, a party who claims to have incurred loss as a result of a defendant's actions, demands a legal or equitable remedy. The defendant is required to respond to the plaintiff's complaint...

s, and some essential fish habitat has yet to be discovered. In the U.S.

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 essential fish habitat is examined and studied by fishery-independent surveys. The fish surveys are standardized, for instance, catch per tow and tow location, to look at spatial relative abundance of fish species.

Marine

Marine reserve

Marine reserve

For the United States Marine Corps Reserve see: Marine Forces ReserveA marine reserve is an area of the sea which has legal protection against fishing or development. This is to be distinguished from a marine park, but there is some overlap in usage...

s (no fishing areas of a marine environment) have emerged, as the forefront of resource policy and management reasons. First, they can protect habitat that has been overharvested and restored. Second, they can help maintain and increase species diversity

Species diversity

Species diversity is an index that incorporates the number of species in an area and also their relative abundance. It is a more comprehensive value than species richness....

. Last, they could possibly help enhance harvest of fish species outside of the reserve.

Creating essential habitat

Artificial reef

Artificial reef

An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block ship passage, or improve surfing....

s are one of best ways to create essential habitat for fish species and are normally created in large bodies of water, like the Great Lakes

Great Lakes

The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...

 and the marine environment. They should be created with clean boulders or riprap

Riprap

Riprap — also known as rip rap, rubble, shot rock or rock armour or "Rip-rap" — is rock or other material used to armor shorelines, streambeds, bridge abutments, pilings and other shoreline structures against scour, water or ice erosion.It is made from a variety of rock types, commonly granite or...

 material and should also be submerged in waters at least three meters or deeper. In some states like North Carolina

North Carolina

North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...

, surplus vessels, steel boxcars, concrete pipe, concrete rubble, boat molds, tires, and surplus military aircraft are used to create artificial reefs in marine environments. This is carried out through a program that was developed in 1988, the DMF Artificial Reef Master Plan. Placement of artificial reefs should be placed near drop-offs and beds of submerge aquatic vegetation (SAV), to provide better utilization by fishes. All of these structures can provide protection from predators and injury from fast moving water bodies. These areas also give fish species a place to rest, hide, feed, and spawn