Salmon leave the inlets like Burrard and go out to deeper waters. Their returns are diminishing to the chagrin of commercial fisheries so that becomes an argument for investing in fish farms. Blocking off inlets was put forward for disussion as an intermediate solution. A population of salmon could be managed and monitored for the entire life span in inlets like Burrard which is as I recall over 10 miles long and 1-2 miles wide at maximum.
----- Original Message -----
From: "Justin C. Johnston" <[log in to unmask]>
Date: Wednesday, March 11, 2009 6:10 am
Subject: Re: Electrofishing workshops (boat and backpack)
To: [log in to unmask]
> Dana,
>
> I'm not sure why you would do such a thing either?
> Generally, barriers are used to protect fish and other organisms
> from inlets to cooling water intake structures. They have
> also been employed to prevent migrations of invasive
> species. For instance the asian carp has apparently been
> prevented from entering the great lakes by the installation of
> an electric weir in the Chicago Sanitary and Ship Canal.
> Control of sea lamprey in Great Lakes Tributaries have included
> electric weirs that allow passage of salmonids and other
> migratory fish while apparently preventing or reducing
> migrations of sea lamprey. The success and/or cost
> effectiveness of these systems is unclear. In terms of
> invasives, it only takes a few to get past and begin
> reproduction for the entire system to be a failure. There
> may be other uses that I am not yet aware of, but to be honest,
> I can't think of a reason why anyone would attempt to block fish
> entry or exit into or out of a harbor. It's doubtful that
> you will prevent an invasive from entering the system and you
> would likely hurt the harbor fishery by doing so. It would
> seem pointless to install a barrier unless there is some
> catastrophy awaiting the fish that do enter the harbor that you
> want to prevent. Maybe Piper is considering preventing
> escaped farmed Atlantic Salmon from entering Pacific
> waters? In which case I would argue 1) It's too late and
> 2) They should probably stop farming the fish there and farm
> native salmonids instead, although the micro-economic
> implications probably prevent this. 3) It seems to me that
> they would be much easier to control by simply removing them
> when they return to spawn with weirs in spawning tributaries and
> selective removal of the species or maybe even just allowing
> anglers and commercial fishermen to keep as many atlantics as
> they want from BC waters. Just some thoughts. I'm
> sure controls are already in place over there by folks much more
> attuned to the situation than I am.
>
> Cheers,
> Justin
>
> -----Original Message-----
> From: Scientific forum on fish and fisheries [mailto:FISH-
> [log in to unmask]] On Behalf Of Dana Haggarty
> Sent: Tuesday, March 10, 2009 10:00 PM
> To: [log in to unmask]
> Subject: Re: Electrofishing workshops (boat and backpack)
>
> Piper,
> This seems like a very strange suggestion to me. For those not
> familiar with
> Burrard Inlet, it is the Vancouver Harbour in Vancouver, British
> Columbia. I
> have no idea why you would want to contain salmon in Burrard Inlet,
> particularly since the natural salmon runs from the streams
> feeding into the
> inlet would also then be contained. Other physical barriers are
> also clearly
> not appropriate giving the shipping and boating activities of
> the busy
> harbour.
>
> Dana Haggarty
>
>
>
> On Tue, Mar 10, 2009 at 2:42 PM, Justin C. Johnston <
> [log in to unmask]> wrote:
>
> > Piper,
> >
> > Smith-Root Inc. makes such devices. I'm not sure about
> the size of the
> > opening at Lions Gate Bridge, but some fairly large inlets could
> > theoretically employ such a technology. Check out
> www.smith-root.com and
> > click on barrier systems. To be honest, they seem to be not
> > cost-competitive with other barrier technologies. Other
> physical (nets,
> > gunderboom, louvre, etc.) and behavioral barriers (acoustic
> and strobes) are
> > either more effective, or more cost effective than
> electrical. In the end,
> > it really depends on what you are trying to keep out, the
> level of success
> > required at keeping them out, and the cost that you are
> willing to pay for
> > such a service.
> >
> > Cheers,
> > Justin C Johnston
> >
> > -----Original Message-----
> > From: Scientific forum on fish and fisheries [mailto:
> > [log in to unmask]] On Behalf Of Piper
> > Sent: Tuesday, March 10, 2009 2:04 PM
> > To: [log in to unmask]
> > Subject: Re: Electrofishing workshops (boat and backpack)
> >
> > Can electronic methods be used to create underwater electric
> fences for
> > fish
> > in ocean inlets?
> >
> > For example, could an electric fence be used under the Lions
> Gate Bridge in
> > Vancouver to keep the salmon within Burrard Inlet as a huge closed
> > containment tank? Or would other methods work better?
> >
> > ----- Original Message -----
> > From: "Eldan Goldenberg" <[log in to unmask]>
> > To: <[log in to unmask]>
> > Sent: Tuesday, March 10, 2009 10:28 AM
> > Subject: Electrofishing workshops (boat and backpack)
> >
> >
> > > NWETC is pleased to announce 2009's schedule of backpack & boat
> > > electrofishing workshops, taught by Dr. Jim Reynolds,
> professor emeritus
> > > at the University of Alaska, Fairbanks.
> > >
> > > Both the boat and backpack versions are three-day courses,
> with most of
> > > the middle day devoted to getting hands-on experience in
> the field.
> > > These will be the public course dates for this year:
> > >
> > > BACKPACK electrofishing, March 23-25 in Santa Cruz, CA
> > > http://nwetc.org/bio-407_03-09_santa_cruz.htm
> > >
> > > BOAT electrofishing, May 20-22 in San Antonio, TX
> > > http://nwetc.org/bio-408_05-09_san-antonio.htm
> > >
> > > BACKPACK electrofishing, September 15-17 in Vancouver, WA
> > > http://nwetc.org/bio-407_09-09_vancouver.htm
> > >
> > >
> > >
> > > Full details and online registration forms are available
> through the
> > > links above.
> > >
> > >
> > >
> > > About the Instructor:
> > > Dr. James B. (Jim) Reynolds is Professor Emeritus of
> Fisheries at the
> > > University of Alaska Fairbanks where he served on the
> faculty during
> > > 1978-1999. Jim is a recognized authority on electrofishing
> and ecology
> > of
> > > northern fishes. He has taught electrofishing short courses
> to over
> > 1,500
> > > biologists in the U.S. and Canada, is the author of the
> chapter on
> > > electrofishing in "Fisheries Techniques" published by the American
> > > Fisheries Society and has written numerous research articles
> on the
> > > subject. Jim is Past President of the Education and
> Fisheries History
> > > sections and Missouri and Alaska chapters of the American
> Fisheries> > Society. He also provided technical guidance for
> the NOAA Fisheries
> > > electrofishing guidelines (see link above). Other
> instructors will
> > assist
> > > during the field portion of the class.
> > >
> > > Registration:
> > > $695 (*$595 reduced tuition available for Native American tribes;
> > > government employees; nonprofits; students; and AFS, NAEP,
> NEBC, NWAEP
> > > members). Group discounts are available for any
> organization sending
> > > more than one person - email me for details. You may
> register via the
> > > URLs above or by calling the Northwest Environmental
> Training Center at
> > > 206-762-1976.
> > >
> > >
> > > ----
> > >
> > > Eldan Goldenberg
> > > Professional Training Program Manager
> > > Northwest Environmental Training Center
> > > A non-profit 501(c)(3) program of EOS Alliance
> > > Improving public health and environmental quality through citizen
> > > engagement and stewardship
> > > v: 206-762-1976 --- f: 206-762-1979
> > > www.nwetc.org
> >
>
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