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					    Atlantic Salmon
      Salmo salar



A species indicator?
Atlantic salmon Life Cycle
                   Wild Atlantic Salmon migration routes




Source: “The Wild Atlantic Salmon-State of the Population in North America 2000 (www.asf.ca)
•Salmon spawn any
time between mid
October to mid or late
November.
•Each female can
produce between
1500-1800
eggs/kg/body weight
•Once the female has
located a site, she
prepares a redd (nest).
        Introduction




 The Atlantic salmon is born in
  fresh water & remains there
      until it undergoes a
  physiological transformation
allowing it to tolerate salt water.
                                               It is during the
                                               smolt stage that
                                               the salmon will
                                               leave the fresh
                                               water river &
                                               migrate to the
                                               salt water sea.
                                               The smolt stage
                                               would be the
                                               equivalent of our
                                               “adolescent”
                                               stage of
                                               development.
•The ALEVINS (hatchlings or fry) & PARR
(yolk sac is gone & actively feeding & free
swimming) will stay in the freshwater system
for usually 2-3 years before reaching the
SMOLT stage.
After 1-3 years at sea, the
salmon returns to its river
of origin (where it was
born!) to spawn
(reproduce). They are now
called grilse. Others will
remain in salt water to
overwinter another season
& will return to fresh water
to spawn as adult salmon.
(>63 cm)

   The soils & vegetation along the streams & rivers play an
   important role in protecting & maintaining salmon habitat.
The vegetation both
nourishes the river
ecosystem & protects
it by stabilizing the
riverbanks,
preventing them
from collapsing &
silting the river.




  A good spawning site will have coarse, loose gravel 3-7 cm
  thick, a moderately strong current to prevent eggs from being
  smothered by settling silt, & well-oxygenated water.
# of
Fish




       Time (year – 19??)
Atlantic salmon situation in Nova
             Scotia??


           2002 FINAL Cumulative
           counts of MSW salmon on
           rivers of the Nova Scotia
           portion of the Maritimes
           Region, as of November 15,
           2002 (Click here to learn
           more)
    Reasons for Species Loss


Siltation              Harvesting
Altering/diverting     Illegal
Water Flow             Harvesting
Erecting Dams or       Logging
Barriers               Aquaculture
Altering/destroying    At-Sea mortality
Riverside Vegetation
Altering/destroying
Riverbanks
                   General Facts about
                      Aquaculture

In 1999, 70 000 tons of   90% of Maritime production
domestic salmon were      comes from Passamaquoddy
raised in Canada          Bay & Grand Manan areas
Presently approx 30       10% from NS & NFLD
companies operating
more than 200 salmon      Aquaculture now accounts
farms on both coasts.     for more than 25% of all fish
(salmon & rainbow trout   consumed by humans
are preferred choice)     worldwide.
Slightly more than 33%    Salmon farming is the fastest
of Canada’s domestic      growing sector in world
salmon output comes       aquaculture.
from the Maritimes.
              Dangers Presented by
                  Aquaculture

In 1997 approx. 300 000 Atlantic salmon were
accidently released into Puget Sound, BC.
In Norway, approx. 1.3 million salmon escape
from farms every year (~33% of the salmon
spawning in coastal rivers in Norway are
ESCAPED domestic salmon!)
There are areas in Norway where escaped
domestic salmon have completely engulfed the
historic range of wild salmon.
     Domestic vs. Wild


Selectively bred     Atlantic salmon
to grow faster       fare better in
(10X faster); tend   captivity than
to be larger &       Pacific salmon
more aggressive      Domestic salmon
Scientists claim     now outnumber
that a genetically   wild salmon by a
engineered           factor of 10 to 1
salmon could be      Do domestic
grown up to 4 m      salmon fall under
in length & weigh    the category of
>80kg!               GM foods?
Current salmon farming practices involve
open netcages like these that allow fish to
 escape & pollution to flow freely into the
           surrounding water.
Problems associated with
    salmon farming…

       Sewage
       Drugs
       Escapees
       Net loss
Waste accumulates beneath salmon
farms, smothering the ocean bottom
        and choking out life.
          Salmon farm pollution…

Organic               Chemical
Main source is fish   Antibiotics
excrement &
                      Pesticides
uneaten food
                      feed additives
The accumulated
waste can smother     paints used on
the organisms and     netcages and boats
set up anoxic         to prevent marine
(oxygen depleted)     growth (antifouling
conditions in the     paints)
seabed sediment.      disinfectants.
Nutrient-loading (N
& P)
Drugs used in the salmon
   farming industry…

 A variety of chemicals, including antibiotics,
 pesticides and fungicides are used on salmon
 farms to treat disease outbreaks.
 These drugs are often administered to the fish
 through their feed.
 Since salmon are mostly raised in open marine
 netcages, most of the drug, or its metabolic
 byproducts, end up in the marine environment
 through uneaten feed or the salmon's
 excrements.
 The distribution and environmental impact of
 these chemicals is a cause of great concern.
   Escaping farmed salmon pose
              risks…
Escaped salmon can be carriers of disease and
parasites, which pose a threat to wild salmon
populations.
When the species farmed is native to an area
there may still be an impact from escaped farmed
salmon breeding with populations of wild salmon
that are genetically adapted to specific streams.
In British Columbia there is a greater danger
arising from the fact that most of the salmon
farmed are Atlantic salmon. Evidence exists that
escaped Atlantic salmon can breed in BC's wild
streams. The potential negative consequences of
this could be dramatic.
average “escapees” in BC is ~90,000 per year for
the period 1990-2000.
    Net loss of wild fish to produce
           farmed salmon…
Salmon farming proponents often point out that, since the wild
fisheries are collapsing, farming the oceans is necessary to feed
a hungry world
They claim that their industry can supply food while taking
pressure off ocean resources. But it isn't that straightforward.
The impact of aquaculture (farming of a seafood species) varies,
depending on what species is farmed and what method is used.
With regard to taking pressure off ocean resources, a key factor
is whether the species being farmed is carnivorous or not.
A total of 2.7-3.5 tonnes of wild fish are used to make 1 tonne of
farmed salmon!
The consumption of 6.2 tonnes of wild fish for each tonne of
salmon produced not only means less food for humans, but also
for the many ocean species that rely on these fish as part of their
food chain. Currently, the continued expansion of salmon farming
is not sustainable.
                   Possible Remedies?

Commitment on the part of Federal & Provincial
Governments
It has been suggested that salmon farms be located
entirely within land-based pens fed by salt water to
create a closed containment system (aquaculture
industry opposed this measure because of the costs
associated with creating the pens)
Sterile, all-female strains of domestic salmon could
reduce threats to wild salmon from cross- breeding with
farm escapees.
“it is only a matter of time before a suitable seed-based
food concentrate can be used to replace marine protein
for feeding domestic salmon” (DFO)
            Sources…

A number of
images in this      News & Issues
presentation are    concerning
from the Atlantic   Aquaculture
Salmon              Facts are located
Federation          at the Nova
website…            Scotia Salmon
                    Association
David Suzuki
Foundation
                    Siltation

  Occurs when a riverbed is covered with fine
  particles.
  Destroys spawning areas & smothers
  salmon eggs.
  Can cause gill abrasion
  Makes feeding more difficult because the
  fish can’t see their food.
Caused by…
   poor or improper road construction
  Irresponsible logging practices
  All-terrain vehicles (ATV’s) in riverbeds
Altering/diverting Water Flow


Water flow is either too high or too
low for the salmon
Affects spawning & survival rates
Erecting Dams or Barriers


  Creates barriers for migrating
  salmon
  Destroys spawning beds
  Example: Kejimkujik National Park
  (dam erected in the 1940’s which
  affected the rivers that drained this
  park)
Altering/destroying Riverside
          Vegetation

   Reduces food supply to the river
   ecosystem
   Causes siltation
 Altering/destroying
     Riverbanks

Causes flooding…which leads to..
SILTATION!
          Harvesting

Native bands that use salmon for
food
The importance of fishing to
Aboriginal communities is
recognized by DFO & given first
priority AFTER conservation.
Conne River Mi’kmaq are the only
band in NFLD with a recognized
food fishery.
Innu Nation & Labrador Inuit
Association have a food fishery in
Labrador.
        Illegal Harvesting




Loss of fish stock due to poaching.
         Logging



Aggravates flooding & causes
flash floods & siltation of water
bodies.
Really impacts on eggs &
juveniles.
Use of insecticides & herbicides
can also be a problem
                 Aquaculture

Declining commercial salmon industry has placed
an emphasis on raising Atlantic salmon in
artificial environments.
A salmonid is a member of the salmon family
which includes salmon, trout, and char.
New Brunswick, Newfoundland & Labrador are
BIG players on the East coast.
If farmed salmon (domestic salmon) escape they
can introduce new disease & new genes into a
watershed producing offspring that are less
suitable for survival.
“Escapees” may also compete for same food
resources.
   At-Sea mortality


A result of ….
by-catch
Global climate change (salinity &
temperature)
Seal predation (suspected but
unproven)

				
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