Skip to main content
U.S. flag

An official website of the United States government

A model for estimating passive integrated transponder (PIT) tag antenna efficiencies for interval-specific emigration rates

January 1, 2007

Our goal was to understand movement and its interaction with survival for populations of stream salmonids at long-term study sites in the northeastern United States by employing passive integrated transponder (PIT) tags and associated technology. Although our PIT tag antenna arrays spanned the stream channel (at most flows) and were continuously operated, we are aware that aspects of fish behavior, environmental characteristics, and electronic limitations influenced our ability to detect 100% of the emigration from our stream site. Therefore, we required antenna efficiency estimates to adjust observed emigration rates. We obtained such estimates by testing a full-scale physical model of our PIT tag antenna array in a laboratory setting. From the physical model, we developed a statistical model that we used to predict efficiency in the field. The factors most important for predicting efficiency were external radio frequency signal and tag type. For most sampling intervals, there was concordance between the predicted and observed efficiencies, which allowed us to estimate the true emigration rate for our field populations of tagged salmonids. One caveat is that the model's utility may depend on its ability to characterize external radio frequency signals accurately. Another important consideration is the trade-off between the volume of data necessary to model efficiency accurately and the difficulty of storing and manipulating large amounts of data.

Citation Information

Publication Year 2007
Title A model for estimating passive integrated transponder (PIT) tag antenna efficiencies for interval-specific emigration rates
DOI 10.1577/T06-053.1
Authors G.E. Horton, T.L. Dubreuil, B.H. Letcher
Publication Type Article
Publication Subtype Journal Article
Series Title Transactions of the American Fisheries Society
Series Number
Index ID 70030116
Record Source USGS Publications Warehouse
USGS Organization