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Development of a micro-acoustic tag for tracking juvenile salmon through estuarine and near-shore marine habitats John W. Ferguson National Marine Fisheries Service, Northwest Fisheries Science Center 2725 Montlake Blvd. East Seattle, Washington USA 98112 Voice: 206 860-3270 FAX: 206 860-3267 john.w.ferguson@noaa.gov Since 2001, we have conducted studies to develop an acoustic tag and detection array(s) to estimate survival, residence behavior, and saltwater-entry timing of both stream- and ocean-type juvenile salmonids emigrating from a variety of watersheds into the Pacific Ocean. The tags will be used to explore mortality mechanisms, characterize salmonid use of freshwater and near-shore marine habitats, and evaluate effects from anthropogenic changes in flow, habitat, and hydropower system operations on the survival of Pacific salmon. Development of a small acoustic tag for use in subyearling fall chinook salmon (Oncorhynchus tshawytscha) as small as 92mm (FL) is a key study element. Our goal is to mark and track a variety of fish groups and life histories (species, stocks, and rearing histories such as hatchery versus wild) to understand the diversity and variability of migration behaviors, habitat selection, and survival through estuarine and near-shore marine environments. To date, use of acoustic tags has been limited to larger, stream-type or yearling-sized juvenile salmon. Our design goal is to develop an acoustic tag that weighs 0.7 g in air and 0.3 g in water, has a volume of 0.4 ml, a size of 17 x 5 x 3.5 mm, a tag life of 30 d at a pulse repetition interval of 8 s, a 420 kHz signal at 150 dB re micro Pascal, and > 64,000 unique codes using a phase shift encoding scheme. A prototype tag weighing 0.9 g in air with a size of 21 x 6 x 4 mm is being tested. We have also designed, deployed, and tested detection hardware to receive signals from these new tags in the acoustically complex environments of the Columbia River and Lake Washington complex in Seattle, WA. Tag design specifications are based on sample size, detection probability, and differential survival criteria from a single-release statistical model. Studies on the effects of the tag on survival, wound healing, and growth have been conducted. Directory: poster poster -> O. P. Singh saarc meteorological Research Centre (smrc) poster -> Super Doubles Competition poster -> Poster to publicize the B. Sc. Program in Computer Engineering What is Computer Engineering! poster -> Professional Career poster -> On-farm studies under Rural Agriculture Work Experience (rawe) Education Programme in India Some results poster -> Computer and Writing in the American University in Cairo (auc) Writing Program: Students' Perspectives poster -> Introduction to Programming: Science or Art? Wanwei Liu, Xiaoguang Mao, Huiping Zhou poster -> Evaluation of the efficacy of a commercial purified phylosilicate to reduce the toxicity of t-2 toxin in broiler chicks poster -> 100 years of john wayne bryan, michael Download 3.88 Kb. Share with your friends:
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