Acoustics is the interdisciplinary science that deals with the study of all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound and infrasound.
Acoustic transmitters (sound emitting tags) used by the Striped Bass Project produce sound at 67 KHz. This means that 67 thousand sound waves are emitted per second.
Striped bass referred to as Age-0 is less than one year old.
Anadromous fish spend most of their adult life in saltwater, but breed in fresh water. The term comes from the Greek words ana and dromos which means ”up; upon; again; back” and ”running, course; race, racecourse”, respectively. The offspring hatch in freshwater and eventually make their way to the ocean.
A fish that lives most of its life in freshwater but spawns in saltwater is catadromus. Cata is Greek for down, downward; under, lower.
Atlantic States Marine Fisheries Commission (ASMFC)
The Atlantic States Marine Fisheries Commission (ASMFC) was formed in 1942 by 15 states along the U.S. Atlantic coast. It was chartered by the United States Congress in 1950 and serves as a deliberative body. The purpose of the commission is to coordinate and manage fishery resources, including marine fish, shellfish and anadromous fish, for the member states. The member states are Main, New Hampshire, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia and Florida.
Brackish water has a higher salinity than fresh water, but is not as salt as seawater.
A fish that lives most of its life in freshwater but spawns in saltwater is catadromus. Cata is Greek for down, downward; under, lower. Catadromous fish hatch in saltwater and migrate to freshwater.
A fish that lives most of its life in saltwater but spawns in freshwater is anadromous.
The number of fish caught for a given amount of effort in fishing for them, e.g. 10 fish/trawl or 10 fish/hour of angling.
Central Receiving Station
The Central receiving Station is a computer located at The Rutgers University Marine Field Station (RUMFS). This computer collects information from the receivers monitoring the hydrophones (listening stations) for the Striped Bass Project. The computer sorts all incoming signals by fish, hydrophone location, time and date.
The locations where the hydrophones have been placed as a part of the Striped Brass Project are called checkpoints. The checkpoints are found in narrow parts of the estuary where fish on the move are naturally forced to swim near the moored hydrophone.
The continental shelf is the extended perimeter of a continent. During glacial periods, much of the shelf was exposed, but today the shelf is submerged by the ocean. The continental shelf off New Jersey, where you can find striped bass, extends about 120 kilometres from the shore to the shelf edge.
Groups of striped bass that migrate and visit habitats on different schedules, or not at all.
Examples of conventional tags are disks, flags, dyes and spaghetti-like tags. They are attached to the fish and used to identify individual fish.
Living or occurring on the bottom of a sea or a lake.
Dissolved Oxygen (DO)
Dissolved oxygen (DO) is molecular oxygen (CO2) present in the water. The oxygen atom in water (H20) is not an example of dissolved oxygen. Oxygen molecules enters the water from the surrounding air, e.g. during rapid water movements, and is also produced by photosynthesizing organisms such as plants.
of, pertaining to, or situated at the back, or dorsum
situated on or toward the upper side of the body (equivalent to the back)
situated on or toward the upper plane
A system involving the interactions between a community of living organisms in a particular area and its nonliving environment.
Essential Fish Habitat (EFH)
The habitat (area and conditions) required for the continued survival of a fish species.
An estuary is formed where the mouth or lower course of a river meets the sea's tide. An estaury can also be an arm or inlet of the sea at the lower end of a river. On the eastern coast of the United States, estuaries are often bays with marshy edges.
A sequence of organisms in an ecosystem in which each species is the food of the next member of the chain. A food chain shows the passage of energy from producers (usually green plants or algae) to other organisms. In a typical predatory food chain, the producers are eaten by primary consumers (herbivores). The herbivores are then devoured by secondary consumers (carnivores). Carnivores may in turn be eaten by tertiary consumers (top carnivores). Organisms can also be consumed by detritivores, e.g. fungi, and detritivores can in turn serve as food for other organisms.
An organism can have multiple roles in a food chain, e.g. because it is both an herbivore and a carnivore. Also note that parasites can live on other organisms without killing the host.
The complex system of interrelated food chains is known as a food web.
The natural environment of an organism; place that is natural for the life and growth of an organism. The habitat may change as the organism goes through various life stages.
A device for locating sources of sound under water. In the Striped Bass Project, battery powerd underwater microphones are wired to a radio and transmit the captured sounds to The Central receiving Station, a computer located at The Rutgers University Marine Field Station (RUMFS). Each hydrophone hangs under a bouy for up to six months. The hydrophones used by the project are WHS-1100 wireless hydrophones manufactured by LOTEK Wireless Inc.
A hypothesis is a proposed explanation for an observable phenomenon. The term is derived from the Greek word hypotithenai, which means “to put under” or “to suppose”. For a hypothesis to be put forward as a scientific hypothesis, the scientific method requires that it is possible to test it.
A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. For some organisms, the transition from juvenile to fully mature is a prolonged process. In such cases, juveniles in the process of making the transition may be referred to as subadults.
Pattern for how migrating animals leave one place to go to another.
Animal migration is the traveling of long distances in search of a new habitat. To be counted as a true migration, and not just a local dispersal or irruption, the movement should be an annual or seasonal occurrence (e.g. birds migration south each winter), or a major habitat change as part of animal's life cycle (e.g. fish born in freshwater migrating to the ocean to spend most of their adult life there).
An item is moored when it is fastened to a fixed object, e.g. a pier or the seabed, or to a floating object such as an anchor buoy.
Mortality rate is a measure of the number of deaths in a population, scaled to the size of that population, per unit time. Mortality rate is typically expressed in units of deaths per 1 000 individuals per unit time (e.g. an hour or a year).
Non-Point Source Pollution
Pollution that enters the environment over a wide area, rather than from a specific point such as a sewage pipe. Chemicals from city streets and farmland runoff is a common example of non-point source pollution.
Omnivores are species that have both plants and animals as their primary food source. The word is a combination of two Latin words, omni which means “everything”, and vorare which means “to devour”.
To overwinter is to pass through or wait out the winter season. In some parts of the world, “winter” is characterized not necessarily by cold but by dry conditions.
For striped bass, the cold water can prevent the fish from being active enough to catch food. Fish with little fat may starve to death. Striped bass living in low flow locales with beneficial salinity and other benevolent conditions require less fat to survive the winter compared to their counterparts in less favorable environments.
A mark-release-recapture method where all animals are tagged and released in one episode. This makes calculation of dispersal and mortality easier.
Piscivors are species that feed on fish.
Plankton (singular plankter) are drifting organisms that inhabit the pelagic zone of oceans, seas and freshwater bodies. Planktons are defines by their ecological niche rather than taxonomic classification. Planktons can be plants, animals, archea or bacteria. The size vary from microscopic organisms to large jellyfish.
The Striped Bass Project uses receivers to listen for and record signals from the hydrophone buoys. The receivers are SRX-500 receivers manufactured by LOTEK Wireless Inc.
A refractometer is a laboratory or field device for the measurement of an index of refraction. A refractometer can for instance be used to quickly measure the salinity and specific gravity of water.
REMUS, Remote Environment Monitoring UnitS, is an autonomous underwater vehicle that supports an acoustic doppler current profiler (ADCP). The vehicle, which is a torpedo-shaped submarine, also measures salinity, temperature, fluorescence and pH-value, and is equipped with sidescan sonar. When REMUS is dropped from a boat, it can follow a programmed path for up to nine hours at a speed of 5 knots.
The total dissolved salt content of a body of water. The salts can for instance be sodium chloride, calcium sulfates and bicarbonates. In sea water, most of the salt will be NaCl (table salt).
In North American and Australian English, the term salinity may also refer to the salt content of soil.
A method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.
Side Scan Sonar
A type of sonar typically used to efficiently create an image of large areas of the sea floor. As the name suggest, a side scan sonar will send out sound waves to both sides of a forward moving ship or submarine. This produces long “shadows” in the echo pattern, thereby covering a wide area at once. Side scan sonar is also known as side looking sonar, side imaging sonar and bottom classification sonar.
When organisms release or deposits eggs and sperm, it is referred to as spawning. The term is most commonly used for aquatic animals. Most fishes, including the striped fish, spawn instead of practicing internal fertilization.
During spawning, striped bass males and females will swim closely together and release sperm and eggs into the water. The striped bass do not lay eggs on the bottom or in a nest. The eggs float away and may drift long distances before they hatch.
The entire area of interest. For the Striped Bass Project, the study area is comprised of the Mullica River from above Lower Bank Bridge to Great Bay and Little Egg Inlet, and it can be extended farther by mobile tracking from boats.
In biology, a substrate is the surface a plant or animal lives upon. Substrates can be biotic (living) as well as abiotic (non living). Coral can for instance grow attached to a rock (abiotic substrate), while algae lives on top of the coral (biotic substrate). Examples of substrates frequently encountered by marine biologists are mud, sand, granule, pebble, cobble, boulders, coral, sea grass and man made structures.
Measuring and reporting information from a distance. The term is derived from the Greek words ele = remote, and metron = measure.
Tides are the rise and fall of water levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun and the rotation of the Earth. Most places in the ocean experience two high tides and two low tides each day (semidiurnal tide). Tidal phenomena are not limited to the oceans, but can occur in other systems such as lakes and the solid part of the Earth.
A transect is a path along which one records and counts occurrences of the phenomena of study, e.g. noting each occurrence of a specific species of plant. A transect is thus a real or imaginary line drawn through an area to help scientists sample and monitor organisms or conditions. The results obtained from studying the immediate area along the line can (but will not always) give an indication representative for the entire habitat.
Something that sends (transmit) something, such as a radio transmitter that sends radio signals. In the Striped Bass Study, each hydrophone is fitted with equipment that change sound signals from tags into radio signals that are sent to the radio receivers. An acoustic transmitter has been placed inside the fish and can be detected from afar by the hydrophones. Acoustic signals are used instead of radio signals, since radio signals do not travel well through saltwater. The tags used are CAFT 16-3 tags manufactured by LOTEK Wireless, Inc.
From Ancient Greek trophikos = “pertaining to food or nourishment”.
Beyond (higher in frequency than) the range of sound perceptible to the human ear. Humans can not hear sound waves with a frequency of 20 kilohertz or higher. The ultrasonic tags used by the Striped Bass Project transmit at 77 Khz.