Efficacy and accuracy of portable PIT-antennae when locating fish in ice-covered streams

Active tracking of passive integrated transponder (PIT)-tags using portable antennae is becoming an increasingly common technique in fish habitat studies in shallow rivers. We carried out “blind testing” to test the efficacy (% tags found) and accuracy (distance between predicted and true tag locati...

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Bibliographic Details
Published in:Hydrobiologia
Main Authors: Linnansaari, Tommi, Roussel, Jean-Marc, Cunjak, R.A., Halleraker, J.H.
Other Authors: Canadian Rivers Institute and Department of Biology, University of New Brunswick (UNB), Écologie et santé des écosystèmes (ESE), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Stiftelsen for INdustriell og TEknisk Forskning Digital Trondheim (SINTEF Digital)
Format: Article in Journal/Newspaper
Language:English
Published: HAL CCSD 2007
Subjects:
HIVER
GLACE
TRANSPONDER
PIT
JUVENILE
EXACTITUDE
EFFICACITE
salmon
atlantic
measurement
saumon de l'atlantique
salmo salar
rivière
méthode de mesure
[SDV]Life Sciences [q-bio]
Salmo salar
Online Access:https://hal.science/hal-01453631
https://doi.org/10.1007/s10750-006-0546-9
Description
Summary:Active tracking of passive integrated transponder (PIT)-tags using portable antennae is becoming an increasingly common technique in fish habitat studies in shallow rivers. We carried out “blind testing” to test the efficacy (% tags found) and accuracy (distance between predicted and true tag location) of a portable antenna system (Texas Instruments) in winter conditions using 23-mm PIT-tags. Up to 90 cm reading range was achieved and signals penetrated ice, rock, wood and water. In the “blind test” trials, a majority of the hidden tags (N = 12–30) were found indicating high tracking efficacy. PIT-tags that were oriented with their cylindrical axis parallel to the plane of the antenna coil inductor loop resulted in a bimodal detection field that had low detection range in the centre of the loop. The utilization of this bimodal detection field proved to be a very accurate method for identifying tag position (mean ± SE distance from predicted to true tag location 10.9 ± 1.4 cm) and thus well suited for microhabitat and activity studies in winter conditions. Aggregations of tags (multiple tags within 1 m2) and obstacles for the antenna maneuvering (e.g., boulders, logjams) reduced the pinpointing accuracy (mean ± SE 13.3 ± 1.8 cm), but the reduction in accuracy was statistically non-significant between the single and aggregated tags.

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