The result of over-fishing and federal mismanagement, Alaska fisheries in the 1940’s and 50’s were in a dismal state. Having once been declared a federal disaster area in 1953, Alaska Salmon runs have been prodigiously healthy now for the last twenty years.

Thanks to the management of the Alaska Department of Fish and Game, sport and commercial fishing is now thriving.

Alaska’s state constitution stands unique in that it specifically mandates that the state’s renewable resources “shall be utilized, developed and maintained on the sustained yield principle.” A direct result of poor management of salmon stock during Alaska’s days under territorial governance, no other state’s constitution addresses conservation of salmon stocks in this manner.

But in order to effectively manage subsistence, sport and commercial fishing in Alaska, solid monitoring and research is paramount. ATS equipment plays an important role in helping the state’s fish and game biologists conduct their important field monitoring operations, thereby providing information critical to the state’s management of salmon runs and ensuring sustainable yields.

In particular, Fish and Game’s Sport Fish Division has held the responsibility for managing the states recreational fisheries resources since 1951. In order to uphold their statutory responsibility to manage fish stocks for sustained yield, the department must rely on scientifically based assessments of these stocks. So, every year, a multitude of studies are undertaken by the Division’s fish biologists.

One such study was conducted recently on the Chilkat River in southeastern Alaska by Randy Ericksen and Richard Chapell, biologists in the Sport Fish Division. Their important work addressed production and spawning distribution of coho salmon; a full stock assessment of the species.

ATS supplied the researchers with 123 model F1845 Implantable Coded Fish Transmitters. These radio tags incorporate a unique coding scheme which minimizes the number of radio frequencies the fish trackers need to monitor. These specialized ATS transmitters were equipped with a switch designed to detect motion, or activity of the fish, and hence fish mortality. Biologists carefully fitted this transmitter within the fish’s stomach and then immediately released the fish. The fish biologist’s carefully excluded smaller fish, since their stomach would not comfortably receive the small radio tags.

The study also utilized five fixed unattended receiving towers, the heart of which consists of the R4500C Scientific Receiver for coded fish tags. The receiver is cabled to a dual antenna array which is supported by a tower. The tower includes a DC power supply which is trickle-charged using two large solar panels. The R4500C scans the frequencies the radio tags are transmitting on. This specialized receiver then automatically logs to its internal memory each tags coded data, and the time the fish passed by the monitoring site (hopefully, on its way to its spawning waters). The receiver minimizes bad data since it uses digital signal processing technology, or DSP, which reduces unwanted and extraneous background noise.

In addition to the fixed monitoring stations, ADF&G also made use of on-foot, boat, and aerial tracking operations in order to complete their study. Aerial tracking allowed the researchers to collect data in areas where fixed monitoring wasn’t feasible. Again, the ATS R4500C was put to use, this time in a Cessna 172. Then, ATS-supplied aircraft antenna mounts were fitted to the aircraft, and ATS four element yagi antennas and cabling were rigged and interfaced to the R4500C Receiver. Even the antenna switching box used is supplied by ATS.

In their report, the researcher’s results show “that 91.5% (SE=3.4%) of the fish that entered the Chilkat River spawned in the drainage, 3% were taken by inriver fisheries, 5% continued upriver movement, but did not reach a spawning area, and less than 1% backed out of the Chilkat River and spawned elsewhere.” Based on this important data, salmon managers base their decisions regarding whether to open or close fisheries in order to ensure spawning escapements are adequate to sustain production.

This is just one of many studies undertaken in Alaska where ATS equipment has played a key role, and at ATS, we’re proud of that role. In fact, since the mid-1980’s, Advanced Telemetry Systems has been helping Alaskan fish and game managers uphold their state’s constitution; our country’s only state where renewable resources are constitutionally protected.