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Glossary

Acoustic: Sound producing. Acoustic transmitters (tags) for this project produce sound at 67 KHz (67 thousand sound waves per second).
Age-0: Less than one year old.
Anadromous: Migrating from salt water to fresh water to spawn, and moving to salt water after hatching in fresh water. Sturgeon, salmon, some herrings, and other fish species besides striped bass are anadromous. Fishes that do the reverse, like American eels that spawn in salt water but live in fresh water, are catadromous.
ASMFC Atlantic States Marine Fisheries Commission: The Commission was formed by the fifteen Atlantic coast states sixty years ago to assist in managing and conserving their shared coastal fishery resources. With the recognition that fish do not adhere to political boundaries, the states formed an Interstate Compact, which was approved by the U.S. Congress. The states have found that their mutual interest in sustaining healthy coastal fishery resources is best achieved by working together cooperatively, in collaboration with the federal government. Through this approach, the states uphold their collective fisheries management responsibilities in a cost effective, timely, and responsive fashion.
Brackish: Water with low salinity.
Catadromous: Migrating from fresh water to salt water to spawn, and moving to fresh water after hatching in salt water. The American eel is an example from US waters. Fishes that do the reverse, like striped bass, sturgeon, salmon, and some herrings are anadromous.
Catch/Unit Effort: The number of fish that are caught for a given amount of effort in fishing for them. For example: five fish per trawl, five fish per hour of angling.
Central Receiving Station: A computer at RUMFS that collects information from the three receivers monitoring the hydrophones (listening stations) and sorts signals by fish, hydrophone location, time, and date.
Checkpoints: The location of a hydrophone. Hydrophones are moored in narrow parts of the estuary where fish coming or going are naturally forced to swim near the hydrophone and be heard. This way, the whole estuary doesn’t have to be monitored.
Continental Shelf: An extension of the same crustal rock that makes up the continent, but submerged underwater. It is relatively flat and can be covered with thick mud and sand layers. Off New Jersey it extends almost 75 miles from the shore to the shelf edge.
Contingents: Groups of striped bass that migrate and visit habitats on different schedules, or not at all.
Conventional tags: Markers used to identify individual fish. They can be spaghetti-like, disks, flags, or dyes and attached to the fish at various points.
Demersal: Bottom dwelling.
Dissolved Oxygen (DO): Molecular oxygen (O2) present in water, not the O in H2O. Oxygen gets into water from the surrounding air, by aeration (rapid movement), and as a waste product from photosynthesis.
Dorsal: Pertaining to the back or upper surface of an animal’s body.
Dynamic: Changing or changeable. For example, water level is dynamic because it changes with tides.
Ecosystem: All the living organisms in a given area and non-living factors with which they interact.
Essential Fish Habitat (EFH): The area and conditions necessary for the continued survival of a fish species.
Estuary: Region where fresh water flows into the ocean. On the east coast of the US, this is often inside shallow valleys that have been flooded by rising sea level, so that estuaries take on the shape of bays with marshy edges.
Food Chain: The passage of energy (food) from producers (plants) up to herbivores (plant-eating animals) and secondary consumers (meat-eating animals).
Habitat: Where an animal lives; its natural home. This may change during the life stages of the animal.
Hydrophone: An underwater microphone. In this study, the microphone is wired to a radio to send what it hears back to RUMFS. The hydrophone has batteries and hangs under a buoy for up to six months. For tracking striped bass we use WHS-1100 wireless hydrophones manufactured by LOTEK Wireless Inc.
Hypothesis: The formal expression of an idea that arises from observing nature. The idea is tested by further observation or experiment in an effort to disprove it. We gain confidence that the idea is accurate after repeated efforts to disprove it fail.
Juvenile: Immature, not fully developed.
Leaving Patterns: How migrating animals leave one place and go to another.
Migration: Two-way journey completed by fish to take advantage of the fact that different needs for different life stages are best provided for in different habitats.
Mooring: Anchor, cable, and buoy system to keep an instrument in place.
Mortality: Death, or a measure of the rate of death, i.e. five deaths per hour.
Non-Point Source Pollution: Pollution that enters the environment over a wide area, not from a place like a pipe. For example: chemicals can enter the water in rain, and oil, salt, and pesticides from city streets or farmland runoff through underground soil. Because this kind of pollution entry is so wide, it is difficult to block.
Omnivorous: Consumes both plants and animals.
Over-Winter: Surviving cold winter conditions. Cold can keep striped bass from being active enough to catch food, and fish with little fat may starve to death. Areas of low flow, the right salinity, and other conditions might allow fish to rest more easily during the winter and thus require less food or fat.
Peterson Method: A mark-release-recapture method in which all animals are tagged and released in one episode so that the calculation of dispersal and mortality is simplest.
Piscivorous: Consumes fish.
Plankton: Aquatic organisms that float along with the currents or have limited swimming abilities.
Receiver: A radio that listens for and records incoming signals, in this case from the hydrophone buoys. For tracking striped bass, we use SRX-500 receivers manufactured by LOTEK Wireless Inc.
Refractometer: A device that shows how far light is bent through a drop of water placed in it. The amount or angle that the light bends is determined by the salinity of the water, so a refractometer is used to quickly measure salinity.
REMUS vehicle: An un-manned torpedo-shaped submarine that supports an acoustic doppler current profiler (ADCP), salinity, temperature, fluorescence, and pH probes in addition to sidescan sonar. The REMUS is dropped from a small boat and follows a programmed path for up to 9 hours at a speed of 5 knots. REMUS knows its position by “listening” to pingers posted underwater at known locations.
Residence: Dwelling in one place for some time.
Salinity: The total dissolved salt content in water. In sea water, most of this salt is NaCl, familiar as table salt, but there are many other kinds included. Coastal ocean water in this region is typically 3.4% (or 34 parts salt per thousand parts water)
Scientific method: A process of learning based on forming an idea (Hypothesis) following an observation and then gathering enough data (additional observations) in a fair and consistent way (unbiased) to test the hypothesis.
Side-Scan Sonar: Sonar that "looks" to the sides. Sound waves are sent out at low angles to both sides of a forward moving ship or submarine. The equipment then listens for the echo and computes the shape of the bottom from how long it takes for the echo to return. Just like shining a flashlight from near the ground, this produces long “shadows” in the echo pattern that are easy to see and interpret ad cover a wide area at once.
Spawn: Shedding of eggs and sperm. Most fishes, including striped bass, do not have internally fertilized eggs, nor do they lay eggs on the bottom or in a nest. Instead, males and females swimming closely together spawn into the water. There, some of the eggs are fertilized as they float away. Eggs may drift miles before hatching.
Study Site: The entire area of interest. For this project, the study area includes the Mullica River from above Lower Bank Bridge to Great Bay and Little Egg Inlet and can be extended farther by mobile tracking from boats.
Substrate: Material upon which an organism lives or to which it is attached, could be rocks, mud, a dock, coral, sea grass.
Telemetry: Literally means "measuring from a distance." In this context - remote sensing of fish presence or position.
Tide: The periodic rise and fall of the sea level resulting from the gravity of the moon and sun on the earth. In New Jersey there are two high tides and two low tides daily.
Transect: To cut sections. Here, a short path followed across a habitat to make measurements representative of the whole habitat.
Transmitter: any device that sends a signal. An acoustic transmitter (tag) sends a sound signal. Radio transmitters send radio signal. Equipment on each hydrophone in this study change sound signals (transmissions) from tags into a radio signal and send that to the radio receivers.
Transmitter: The combination of a small speaker (acoustic) or radio, a battery, and a computer processor to send a signal. For this project, the transmitter is placed inside the fish and acts like a tag that is detected from afar by a hydrophone. This project uses acoustic transmitters because a radio signal won’t travel through salt water. For tracking striped bass, we use CAFT 16-3 tags manufactured by LOTEK Wireless, Inc.
Trophic: Pertaining to nutrition, food or growth
Ultrasonic: Sound waves with such high frequency (number of waves passing a point in a second), that they cannot be heard by the human ear. Ultrasonic tags for this study transmit at 77 KHz (77 thousand waves per second).
YSI meter: An instrument made by Yellow Springs Instrument Company that measures salinity, temperature, pH, and dissolved oxygen electronically from a probe lowered into the water. The values are displayed on a screen or saved in a memory file.