Rutgers University Problem

Do fish in the ocean have favorite places?

Investigation Explanation Journal COOL New Terms Index Unit Plan Back to COOL Classroom

Fish Migration

COOL Terms

Acoustics the study of all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound and infrasound.
Acoustic tags tags that make a sound at 67 KHz. This means that 67 thousand sound waves are emitted per second.
Age-0 less than one year old.
Anadromous fish that spend most of their adult life in saltwater, but breed in fresh water. The eggs hatch in freshwater and the young fish eventually make their way to the salty ocean.
Atlantic States Marine Fisheries Commission (ASMFC) a group formed in 1942 by 15 states along the U.S. Atlantic coast. Their job is to help people share the fish in the ocean off Main, New Hampshire, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia and Florida.
Brackish water with some salt in it, but not as salty as seawater.
Catadromous a fish that lives most of its life in freshwater but lays its eggs in saltwater.
Catch/Unit Effort the number of fish caught for a given amount of effort in fishing for them. For example if 10 fish were caught in one trawl it would be 10 fish/trawl or if 40 fish were caught in 4 hours of angling, then it would be 10 fish/hour (average of 10 fish for every hour out fishing).
Central Receiving Station a computer located at the Rutgers University Marine Field Station (RUMFS) in Tuckerton that collects information from the receivers listening to the hydrophones for the Striped Bass Project. The computer sorts all incoming signals by fish, hydrophone location, time and date.
Checkpoints the locations where the hydrophones have been placed to hear the fish. Normally placed in narrow spots so fish are naturally forced to swim near the anchored hydrophone.
Chlorophyll the green-coloring matter of leaves and phytoplankton where photosynthesis happens
Continental Shelf a shallow extension off the coast of most continents that is shallow compared to the deep open ocean. The continental shelf off New Jersey, where you can find striped bass, extends about 120 kilometers (about 60 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 commonly used tags including disks, flags, dyes and spaghetti-like tags. They are attached to the fish and used to identify individual fish.
Demersal living or happening on the bottom of a sea or a lake.
Dissolved Oxygen (DO) oxygen that is dissolved in the water. Oxygen enters the water from the air when water bubbles and splashes over rocks. Underwater plants also add oxygen to the water as they live and grow (photosynthesis).
Dorsal back. A dolphin’s fin is on its dorsal side (back).
Ecosystem an area in which living and nonliving factors interact.
Essential Fish Habitat (EFH) the area and conditions required for the continued survival of a fish species. Conditions include the right amount of dissolved oxygen, the right temperature range, and enough food for survival.
Estuary an area where a river meets the sea. On the eastern coast of the United States, estuaries are often bays with marshy edges, like the Barnegat Bay.
Food Chain a sequence of living things in an ecosystem that eat each other. For example the fly was eaten by the spider which was eaten by the bird which was eaten by the cat. A food chain shows the passage of energy from producers (usually green plants or algae) to other organisms.
Lots of food chains woven together is known as a food web.
Habitat the place that is natural for the life and growth of an organism. The habitat may change as the organism goes through various life stages.
Hydrophone a piece of equipment that hangs under a floating buoy and finds sources of sound underwater. In the Striped Bass Project, battery-powered underwater microphones are wired to a radio that sends the captured sounds to The Central Receiving Station.
Hypothesis a carefully thought out idea of how things work (not a random guess). For a hypothesis to be put forward as a scientific hypothesis, the scientific method requires that it is possible to test it.
Juvenile an individual organism that has not yet reached its adult form.
Leaving Patterns pattern for how migrating animals leave one place to go to another.
Migration the traveling of long distances in search of a new habitat. To be counted as a true migration, the movement should be an annual or seasonal occurrence (for example bird migration south each winter), or a major habitat change as part of animal’s life cycle (for example fish born in freshwater migrating to the ocean to spend most of their adult life there).
Mooring a fixed object (like a pier, dock, or the seabed) OR a floating object (like a buoy) that something is anchored to in the water so it will stay in one place and not drift away with the tide or currents.
Mortality rate a measure of the number of deaths in a population
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 is a common example of non-point source pollution.
Omnivores species that eat both plants and animals as their primary food source.
Overwintering to pass through or wait out the winter season. In some parts of the world, “winter” is characterized not by cold temperatures 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 calm water that isn’t too cold require less fat to survive the winter.
Peterson Method a mark-release-recapture method where all animals are tagged and released at one time.
Piscivors species that feed on fish.
Photosynthesis the process in which sunlight energy is transformed into food
Phytoplankton drifting organisms that inhabit the upper area of oceans, seas and freshwater. Though they are NOT plants, they do perform photosynthesis. They are extremely small microscopic organisms.
Receiver a piece of equipment used to listen for and record signals from hydrophone buoys.
Refine to make more precise. In science this happens because of more or new information.
Refractometer a piece of equipment used to measure the speed of light through a substance. A refractometer can be used to quickly measure how much salt is in the water.
REMUS vehicle R*emote *E*nvironment *M*onitoring *U*nit*S, an underwater vehicle that is shaped like a torpedo and is about 5 feet long. It measures water currents, 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.
Salinity a measure of how much salt is dissolved in the water. In sea water, most of the salt will be sodium chloride (table salt), but there can be other forms like calcium sulfates and bicarbonates.
Scientific method step-by-step procedures that include systematic observations, measurement, and experiment to form, test, and modify a hypothesis.
Side Scan Sonar a type of sonar used to create a picture of large areas of the sea floor. It sends out sound waves on both sides. This creates long “shadows” in the echo pattern, covering a wide area at once. Side scan sonar is also known as side looking sonar, side imaging sonar and bottom classification sonar.
Spawning Striped bass do NOT lay eggs on the ocean bottom or in a nest. Instead, female and male striped bass swim closely together. Females release eggs into the water and the males fertilize the eggs. The eggs then float away and may drift long distances before they hatch.
Study Site the entire area of interest for the scientist. 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.
Substrate the surface a plant or animal lives on. Coral can grow attached to a rock, while algae lives on top of the coral. Examples of substrates frequently encountered by marine biologists are mud, sand, granule, pebble, cobble, boulders, coral, sea grass and man-made structures (docks, boats, bulkheads, bridges, etc.)
Telemetry measuring and reporting information from a distance.
Tide 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.
Transect a path along which one records and counts what they are interested in studying. So a transect is a real or imaginary line drawn through an area to help scientists sample and monitor organisms or conditions. The results from studying the immediate area along the line can (but will not always) give information for the entire habitat.
Transmitter a piece of equipment 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.
Trophic pertaining to food or nourishment
Ultrasonic Beyond the range of sound humans can hear. The ultrasonic tags used by the Striped Bass Project transmit at 77 Khz.
Zooplankton microscopic to small floating ocean animals
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