Non-lethal Deterrence of California sea lions at
Bonneville Dam Ballard Locks
Steven Jeffries, Washington Department of Fish and Wildlife Robin Brown, Oregon Department of Fish and Wildlife Brent Norberg, NOAA-Fisheries Robert Stansell, U.S. Army Corps of Engineers
Pinniped-fishery interaction task force 4 September 2007
MMPA Section 109(h) [TAKING OF MARINE MAMMALS AS PART OF OFFICIAL DUTIES.] (1) Nothing in this title or title IV shall prevent a Federal, State, or local government official or employee or a person designated under section 112(c) from taking, in the course of his or her duties as an official, employee, or designee, a marine mammal in a humane manner (including euthanasia) if such taking is for— (A) the protection or welfare of the mammal, (B) the protection of the public health and welfare, or (C) the nonlethal removal of nuisance animals. (2) Nothing in this title shall prevent the Secretary or a person designated under section 112(c) from importing a marine mammal into the United States if such importation is necessary to render medical treatment that is not otherwise available. (3) In any case in which it is feasible to return to its natural habitat a marine mammal taken or imported under circumstances described in this subsection, steps to achieve that result shall be taken.
• physical barriers • acoustic barriers • land and/or vessel harassment • seal bombs • crackershells/shellcrackers • rubber bullets
Options for non-lethal deterrence of sea lions
SLEDs
• Sea lion exclusion devices (SLEDs) installed at fishway entrances
• 12 entrances, 2 sections each, 15 3/8” gaps• Designed to allow salmon passage
© 2006 by Transco Industries, Inc.
Physical barriers 2 = SLEDs
Acoustic Deterrent Devices (ADD)
• 205 decibel, 15 kHz frequency acoustic projectors installed at fishway entrances
• March – May 2006• ADDs turned on at 0500 hrs on hazing days, turned off at 2000
hrs at the end of each 2-day treatment• No significant effects on salmon passage
Acoustic barriers = Acoustic Deterrent Devices
Other barriers ie Smith Root electric shock grid
Does it impact fish passage? Will it work on CA sea lions ?
Where can it be deployed?
CA Sea Lion Deterrent Activities at Bonneville Dam
•2005: Initial tests – From land and boats, 2 days in April; 2 days in May •2006: Full evaluation tests ACOE/States/CRITFC) for effects on fish passage; 2 days on-off, 4 days on-off, April-May •2007: Total hazing program 7 days/week– ACOE/WS from dam/shore Feb-May; States/CRITFC from boats March-May
Feb Mar Apr May
2007
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