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Title: Multi-scale temporal patterns in fish presence in a high-velocity tidal channel

Abstract

The natural variation of fish presence in high-velocity tidal channels is not well understood. A better understanding of fish use of these areas would aid in predicting fish interactions with marine hydrokinetic (MHK) devices, the effects of which are uncertain but of high concern. To characterize the patterns in fish presence at a tidal energy site in Cobscook Bay, Maine, we examined two years of hydroacoustic data continuously collected at the proposed depth of an MHK turbine with a bottom-mounted, side-looking echosounder. The maximum number of fish counted per hour ranged from hundreds in the early spring to over 1,000 in the fall. Counts varied greatly with tidal and diel cycles in a seasonally changing relationship, likely linked to the seasonally changing fish community of the bay. In the winter and spring, higher hourly counts were generally confined to ebb tides and low slack tides near sunrise and sunset. In summer and fall of each year, the highest fish counts shifted to night and occurred during ebb, low slack, and flood tides. Fish counts were not linked to current speed, and did not decrease as current speed increased, contrary to observations at other tidal power sites. As fish counts maymore » be proportional to the encounter rate of fish with an MHK turbine at the same depth, highly variable counts indicate that the risk to fish is similarly variable. The links between fish presence and environmental cycles at this site will likely be present at other locations with similar environmental forcing, making these observations useful in predicting potential fish interactions at tidal energy sites worldwide.« less

Authors:
 [1]; ORCiD logo [1];  [2]
  1. Univ. of Maine, Orono, ME (United States). School of Marine Sciences
  2. Univ. of Waikato (New Zealand)
Publication Date:
Research Org.:
Univ. of Maine, Orono, ME (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1393570
Grant/Contract Number:
EE0003647
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
PLoS ONE
Additional Journal Information:
Journal Volume: 12; Journal Issue: 5; Journal ID: ISSN 1932-6203
Publisher:
Public Library of Science
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 59 BASIC BIOLOGICAL SCIENCES

Citation Formats

Viehman, Haley A., Zydlewski, Gayle Barbin, and Hewitt, Judi. Multi-scale temporal patterns in fish presence in a high-velocity tidal channel. United States: N. p., 2017. Web. doi:10.1371/journal.pone.0176405.
Viehman, Haley A., Zydlewski, Gayle Barbin, & Hewitt, Judi. Multi-scale temporal patterns in fish presence in a high-velocity tidal channel. United States. doi:10.1371/journal.pone.0176405.
Viehman, Haley A., Zydlewski, Gayle Barbin, and Hewitt, Judi. Thu . "Multi-scale temporal patterns in fish presence in a high-velocity tidal channel". United States. doi:10.1371/journal.pone.0176405. https://www.osti.gov/servlets/purl/1393570.
@article{osti_1393570,
title = {Multi-scale temporal patterns in fish presence in a high-velocity tidal channel},
author = {Viehman, Haley A. and Zydlewski, Gayle Barbin and Hewitt, Judi},
abstractNote = {The natural variation of fish presence in high-velocity tidal channels is not well understood. A better understanding of fish use of these areas would aid in predicting fish interactions with marine hydrokinetic (MHK) devices, the effects of which are uncertain but of high concern. To characterize the patterns in fish presence at a tidal energy site in Cobscook Bay, Maine, we examined two years of hydroacoustic data continuously collected at the proposed depth of an MHK turbine with a bottom-mounted, side-looking echosounder. The maximum number of fish counted per hour ranged from hundreds in the early spring to over 1,000 in the fall. Counts varied greatly with tidal and diel cycles in a seasonally changing relationship, likely linked to the seasonally changing fish community of the bay. In the winter and spring, higher hourly counts were generally confined to ebb tides and low slack tides near sunrise and sunset. In summer and fall of each year, the highest fish counts shifted to night and occurred during ebb, low slack, and flood tides. Fish counts were not linked to current speed, and did not decrease as current speed increased, contrary to observations at other tidal power sites. As fish counts may be proportional to the encounter rate of fish with an MHK turbine at the same depth, highly variable counts indicate that the risk to fish is similarly variable. The links between fish presence and environmental cycles at this site will likely be present at other locations with similar environmental forcing, making these observations useful in predicting potential fish interactions at tidal energy sites worldwide.},
doi = {10.1371/journal.pone.0176405},
journal = {PLoS ONE},
number = 5,
volume = 12,
place = {United States},
year = {Thu May 11 00:00:00 EDT 2017},
month = {Thu May 11 00:00:00 EDT 2017}
}

Journal Article:
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