Acoustic tag

Acoustic tags are small sound-emitting devices that allow the detection and / or remote control of fish in three dimensions for fisheries research. Acoustic telemetry (including acoustic tags) are commonly used to monitor the behavior of fish. Studies can be conducted in lakes , rivers , tributaries , estuaries or at sea . Acoustic tag tracking technology allows researchersto view 3D fish tracks in real-time with sub-meter resolution. Acoustic tags have been employed to help public utilities, private firms, and state and federal agencies as defined by the Federal Regulations and Oversight of Energy known as FERC .

Acoustic tags come in an assortment of sizes and weights. To-date, the smallest acoustic tag successfully in the field was measured 0.65 grams (tracking a juvenile salmonid at a length of 125 mm). Tag size increases significantly for longer periods of time (ie sturgeon).

Overview

Examples of acoustic tag sizes

Acoustic tags allow researchers to:

  • Conduct Fish Survival Studies
  • Monitor Fish Migration / Passage / Trajectory
  • Track Fish Behavior in Two or Three Dimensions (2D or 3D)
  • Measure Bypass Effectiveness at Dams and other Passages
  • Regards Predator / Prey Dynamics and More

Acoustic Tags transmit a signal made up of acoustic pulses or “pings” that sends the information about the fish to the hydrophone receiver. By tying the received acoustic signature of The Known to the type of programmed code signal, a specific fish is APPROBATION. The transmitted signal can propagate up to 1 km (in freshwater). Each “ping” comes at a predetermined interval. The signals are encoded for strength to improve range and resolution. Thus, an array of receivers allows the user to record the movement of a particular fish over many kilometers. Unique to Acoustic Tags is the ability to have 100,000 user-specified individual tags. These variables allow a custom fit for unique projects.

By determining the sound of each hydrophone, the position of the fish can be calculated. The hydrophone receiver picks up the sound signal and converts it to data that results in three dimensions, in real-time. Using a post processing software, such as MarkTags , takes the data and delivers the result, the 3D track.

Acoustic tags can be attached to, gastrically inserted in or surgically implanted into fish (or almost any aquatic life).

Several types of methods are used to attach the tag to the fish. The tag may be embedded in a small incision in the abdominal cavity of the fish (surgical implantation), or put to the gullet to embed the Acoustic Tag in the stomach (gastric implantation). External attachment using adhesive compounds is typically used for fishes.

Details

Illustration of juvenile salmonidtraveling through a fish by-pass intake.
Acoustic tag tracking software screen of fish tracking towards a fish bypass intake (side view).

Acoustic Tags are produced in many different shapes and sizes depending on the type of species being studied, or the type of environment in which the study is conducted. Sound parameters Such As frequency and modulation method are Chosen for optimum detectability, and signal level. For oceanic environments, frequencies less than 100 kHz Often ranks are used, while frequencies of Several Hundreds of kilohertz are more common in for studies in rivers and lakes.

A typical Acoustic Tag consists of a piezoceramic transducer , drive / timing electronics, and a battery power source. Cylindrical or “tube” transducers are often used, which have metalization on the inner and outer walls of the structure. In normal operation, an alternating current (AC) electrical signal generated by the drive / timing electronics is impressed across the two metalization layers. This voltage creates stress in the material, which in turn causes the transducer to emit an acoustic signal or “ping”, which emanates outward from the surface of the tube. An acoustic “ping” can be detected by specialized receivers, and processed by a specific acoustic signal.

Tags: passive inductive transponder tags (PIT) Tags: Tags: tags, tags, tags, tags, tags, tags fish in a particular path (PIT tags require the fish to be routed through a restricted sensing area).

Applications

At present, acoustic tags are most commonly used to monitor fish approaching diversion and guidance structures at hydropower dams. This Allows hydropowered dam facilities, public utility districts and Municipalities to evaluate-specific migration pathways used by the fish (most Often salmon smolts), identify Where fish mortality OCCURS and for Assessment fish behavior in relation to hydrodynamic condition and / or Any Other environmental parameters. Ultimately, working to improve the efficiency and effectiveness of fish populations, Acoustic Tag Tracking Systems are a significant breakthrough in the preservation of migrating salmon populations. For an example of Acoustic Tag Tracking Systems at work on the River Columbia , see Grant County’s most recentgold application Chelan County’s most recent application .

See also

  • Animal migration tracking
  • Data storage tag
  • GIS and aquatic science
  • Pop-up satellite archival tag

References

  • A Multiple-Release Model to Estimate Route-Specific and Damage Survival at a Hydroelectric Project permanent dead link ]
  • Movement and Habitat Use of Chinook Smolts Salmon, Northern Pikeminnow, and Smallmouth Bass Near the SR 520 Bridge
  • Basin-wide Monitoring of Salmon Smolts at US Dams
  • Categorizing Salmon Migration Behavior Using Characteristics of Split-beam Acoustic Data
  • Basin-Wide Monitoring of Acoustically Tagged Salmon Smolts at Dams Hydropower in the Mid-Columbia River Basin, USA
  • Correcting Bias in Survival Estimation from Tag Failure in Acoustic and Radiotelemetry Studies
  • Chinook, Steelhead and Sockeye Salmon (Oncorhynchus, spp.) Passing Dams on the Columbia River, USA
  • A Method for Estimating the Position Accuracy of Fish Tags
  • Monitoring the Three-Dimensional Behavior of Acoustically Tagged Salmon Approaching Dams Hydropower in the Pacific Northwest permanent dead link ]
  • Monitoring the Behavior of Acoustically Tagged Chinook and Steelhead Smolts Approaching Rocky Reach Dam on the Columbia River
  • Additional Publications

Leave a Reply

Your email address will not be published. Required fields are marked *