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The Threat to Atlantic Salmon Caused
by the Invading Smallmouth Bass
By: Andrew Dang, Kaitlyn Seow, Priya
Khoral, Rajat Goswami, Rashiq Shahad,
Sravanthi Dornadula, Zoe Hoskin
The Atlantic Salmon–
Salmo Salar
Kingdom - Animalia
Phylum - Chordata
Class - Osteichythes
Order - Salmoniformes
Family - Salmonidae
Genus - Salmo
Species - Salmo salar
More information on the Atlantic Salmon:
⁻ It is at risk due to invasive species
⁻ It is a Cold Water Fish
⁻ Average Length – 25-70cm
⁻ Average Weight – 0.9-3.6kg
⁻ Distinguished by: silvery colour, spotted and deformed during the spawning season, small
scales, a round dorsal fin, comparatively large size, bodies are long and thin
Habitat and Development
⁻ They have a different habitat for each stage in their life cycle
⁻ There are two types of Atlantic Salmon – the best-known migrates from its spawning
location to the Atlantic Ocean and returns to lay its eggs, other type never travels to the
ocean – commonly referred to as ‘landlocked’
⁻ Oceanic salmon travels down-river to Atlantic Ocean, landlocked travel into an inland lake
⁻ Both become sexually mature after several years in lake/ocean
⁻ They undergo several physical changes and force themselves upriver back to their
breeding ground
⁻ First few years of life, young salmon remain in the inland water where they were born
later, develop into “smolts”, oceanic/landlocked salmon take different path
⁻ Oceanic salmon have harder time to return to river – results in decrease in salmon
population
Habitat and
Development Continued
⁻ In Canada, the salmon spawn in
October/November, depending
on the region
⁻ When migrating upstream, they must
surmount obstacles (natural and man-made) to
reach the spawning grounds
⁻ “Spawning site is usually a gravel-bottom riffle area above or below a pool”
⁻ Female will dig a nest with her caudal fin, and when she is finished spawning, she
will cover the eggs with gravel
⁻ The eggs hatch in about 110 days, young emerge from gravel in May/June
young remain in the river/stream until they are about 65mm long
⁻ Age which they leave for the ocean varies depending on region, 2-3 years in the
Martime, 4-8 years in the Ungava region
Salmon Ova
•
•
•
•
Spawning season for salmon generally start
midway through August and ends in November
(approximately 3 months long)
Female salmon digs a type of nest with her fins
and deposits the eggs into it so she may cover
the eggs with gravel
Salmon eggs hatch within 110 days
Salmon eggs hatch only if the water
temperature is warm enough which is usually
sometime in early spring
Spawning Female Salmon
• Atlantic salmon return
to the river that they
were spawned in even
after leaving to the
ocean when it is not
spawning season
• Female salmon may
carry and deposit 600800 eggs/lb of body
weight
• Atlantic Salmon eggs
are usually pale
orange and have a
diameter of 5-7 mm
Spawning Male Salmon
• During spawning season, male salmon
darken to low brown tones to red
• This is to appeal to female salmon
Importance of Nesting Grounds
• Because salmon are
frequently moving to
their original
spawning area, if it is
changed even in the
slightest because of
pollution or
construction, this
could result in the
decrease of the
salmon population
•Even the lowering of water levels may effect salmon
numbers
•This decreases movement and the number of salmon
able to pass through the rivers at once as well as leaving
salmon eggs to become vulnerable
Atlantic Salmon Feeding
⁻ They feed on crustaceans and fishes
such as smelt, herring, and small
mackerel and cod
⁻ Young salmon in streams feed mainly on
aquatic insect larvae
Distribution of the Atlantic
Salmon
⁻ Native species to the North Atlantic
Ocean
⁻
In Canada, they are found throughout Newfoundland, Labrador, the Maritime
Provinces, eastern Quebec, and the Ungava region of Northern Quebec
⁻ Introduced in the Pacific southwest and the Pacific southeast
number of landlocked populations throughout the distribution
⁻ They are now at risk because of competition from other fish, due to overlapping
niches
What is a Niche?
In ecology, a niche is a term describing
the relational position of or population
in its ecosystem to each other. In this
case, the niches of the salmon and
the invading bass are overlapping
An organism’s niche is unique to its
environment. However, when an
invasive species enters the
environment, this poses a huge threat
to the pre-existing organisms.
This causes an increase in
competition for survival thus
one species will have to
dominate over the other.
As a result, the equilibrium in the ecosystem will
be imbalanced therefore jeopardizing survival rates
for all other organisms.
Different Niches a Fish can
Occupy
1)
2)
3)
4)
5)
Water Temperature (°C)
Water Salinity (ppt)
Vegetation
Distribution
Habitat Specifics
Water temperature test - Bay of Fundy
Temperature/Salinity
Temperature:
• Atlantic Salmon – When
at its adult stage, the
Atlantic Salmon has a
temperature tolerance
range from 8°C - 23°C
• Smallmouth Bass - 4°C 15.5°C
Salinity of Water:
• Atlantic Salmon –
Tolerance at 35.5 ppt
• Smallmouth Bass –
Tolerance at 24.4 ppt
Vegetation
Types of Vegetation
• Atlantic salmon - Feed on a
variety of organisms including
crustaceans and fishes, such as
smelt, herring and small mackerel
and cod.
•
Smallmouth bass – Feed is mainly
composed of insects, crayfish and
fishes.
Distribution
Distribution:
• The Atlantic salmon is native
to the basin of the North
Atlantic Ocean. In Canada, the
Atlantic salmon occurs
naturally throughout
Newfoundland, Labrador, the
Maritime Provinces, eastern
Quebec and the Ungava
region of northern Quebec.
• The Smallmouth Bass can be
found in southern Nova Scotia,
southern and western New
Brunswick, southern Quebec.
Map of the Maritimes (Canada)
Habitat Specifics
• The Atlantic salmon is a cold-water species and
like most migratory fishes, it has a different
habitat for each stage of its life history. Marine
Atlantic salmon return from the sea to freshwater
streams to spawn.
• The Smallmouth bass is a warm-water fish
species, usually found in rocky and sandy areas
of lakes and rivers in moderately shallow water
and near rocks of shoals or submerged logs.
• Because the bass is an invasive species
whose niche overlaps with the salmon’s,
competition has ensued
What are Invasive Species?
Invasive species:
Species of animals that are released into an environment where they do not normally
belong. It disrupts the natural balance of it’s ecosystem and result in the elimination of
populations in the area and or their food source.
Other Problems Caused by these species include:
-
The spread of disease
An increase in the number of parasites
They create competition for food sources
They occupy space and other resources, disrupting existing habitats
Invasive Species to Atlantic Salmon Include:
-
Rainbow Trout
Didymosphenia geminata (type of Algae)
Small Mouth Bass, Large Mouth Bass, Pike
Rainbow
Trout
The most concerning of the invasive species affecting Atlantic Salmon in New Brunswick’s
Miramichi Lake, however, is the smallmouth bass.
The Smallmouth Bass –
Micropterus Dolomieui
Kingdom - Animalia
Phylum - Chordata
Class - Actinopterygii
Order - Perciformes
Family - Centrarchidae
Genus - Micropterus
Species - M. dolomieui
More information on the Smallmouth Bass:
-
It is a warm water fish species
Lives in lakes and rivers (shallow)
Eats insects, crayfish and fishes
Spawns from late May to early July
Males build nests in shallow sandy, rocky area
Male fecundity' is the term for number of eggs in a nest
History of the Species:
“They have been moved all over the United States since 1825, when construction of the Erie
Canal extended their range into central New York state. ”
“Studies of introduced smallmouth bass have already shown that they have devastated trout
populations on the East Coast. Tahoe's lake, brown and rainbow trout could also be in
jeopardy. The alien fish could hamper efforts by the U.S. Fish and Wildlife Service to reintroduce native Lahontan trout to the Sierra lake.”
Invasive qualities of the Species:
-
Smallmouth bass are highly aggressive
-
They endanger water clarity by “excreting nutrients that cause algae blooms” An example
of where this occurs is Lake Tahoe
-
Water clarity is often measured by planting a white disk in the lake at a certain depth and
seeing how long it is visible for
What caused the species to invade?
-
The bass were likely introduced to Miramichi Lake located in New Brunswick: a prime trout
and Atlantic salmon habitat
It connects to the outlet of Lake Brook, 5km long and flows into the Main Southwest
Miramichi River.
Miramichi River extends for 20km
Miramichi
Lake
Why is this a problem?
-
Small Mouth Bass are known to be prized fish for their aggressive behaviour.
The fishing industry around Miramichi Lake is centred mainly around trout and salmon
The changes in food chains caused by a decline in Atlantic Salmon would affect not only the
lake, but all of the rivers it feeds, and even the oceans, as adult salmon migrate there. This
would become an international problem
Then why did it happen?
-
It is unknown how Small Mouth Bass was introduced into the lake but it is believed
someone moved the species from one body of water to another.
This is illegal in the Province of New Brunswick and can result in a fine of $100 000
However, fishermen have been known to undertake in the activity for sportive fishing
purposes and to catch fish not readily available in the area.
Invasive species are plants, animals, aquatic life and
micro-organisms that outcompete native species
when introduced outside of their natural
environment and threaten Canada’s ecosystems,
economy and society.
Invasivespecies.gc.ca
Invasive species generally share common
characteristics which makes them difficult to control.
 Higher rate of reproduction
 Fewer natural predators
 Ability to thrive in different environments
Introducing and Spreading Invasive
Species






Invasive species are a cost of globalization. They are
introduced and spread through various ways:
Goods such as firewood, plant products or wood packaging.
Live food imports
Aquarium and Horticultural imports
Vehicles such as aircraft, commercial and recreational
boats.
Ballast water from large ships
Diseases in wildlife, which spread rapidly over wide areas
CANADA’S RESPONSE
Federal Law
Canada Wildlife Act
Forestry Act
Canadian National Parks Act
Department of Natural Resources Act
Fisheries Act
Canada Shipping Act
Canadian Environmental
Assessment Act Canadian Environmental
Oceans Act
Pest Control Products Act
Protection Act
Regulation of International
and Interprovincial Act
An Invasive Alien Species Strategy for Canada aims to
reduce the risk of invasive species to the environment,
economy and society, and to promote environmental
values such as biodiversity and sustainability.
Goals
 To prevent the harmful intentional and unintentional
introduction of invasive species to Canada
 To detect and identify new invaders;
 To respond rapidly to new invaders upon detection;
and
 To manage established and spreading invaders
through eradication containment and control
Our Responsibility (General)
 Many invasive species are not easily visible to the
naked eye. Leave natural items- like animals, plants,
seeds, insects, wood products, soil and water in their
natural habitats to avoid the introduction and spread
the invasive species.
Our Responsibility (General)
 Plants, animals and aquatic life bought on the internet
or in a store can impact Canada’s ecosystem if they
accidentally escape or if you can no longer care for
them. With no natural predators they could
overwhelm the ecosystem in which they are released.
 Learn about invasive species and ballast water and the
Canadian Ballast water program- educate yourself and
community.
 Do not release fish into drainage system from which it
did not originate.
 Do not transport water from one system to another, as
it may contain unseen parasites or larvae that could
have damaging effects in new waters.
 Take preventative measures to prevent climate
change. Climate charge will have dramatic impacts on
native coldwater fishes.
 Protect lakes (especially smaller lakes) because they
are more likely to contain more stressful abiotic
conditions such as increased water temperatures and
lower oxygen levels.
Two Methods on Dealing With
Invasive Species:
Actively (after the problem)
Or
Proactively (before the problem)
Actively:
“As there is only one exit waterway from Miramichi Lake, a
barrier was erected to monitor all fish going in and out of the
lake and selectively remove any small-mouth bass.”
– Nelson Poirier
Electrofishing (the process of electrifying water to stun the
fishes, then touring the area to remove smallmouth bass)
Both are intended as non-lethal methods
Actively Continued:
A more extreme method
– as used in some
Ontario lakes and BC
lakes – is to apply a
chemical called rotenone
to the lake, killing all
species. Then only
native species are
reintroduced
Proactively:
Dealing with Invasive Species Proactively
• Don’t buy invasive species as pets
• Follow the governments fishing laws
In Conclusion:
• Regardless of how cut off
we seem from invasive
species, they do affect us
via industry and laws put in
place to manage them
• It is our responsibility to do
what we can to stop the
spread of invasive species
and protect those that are
vulnerable
Bibliography
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Asf's river notes offers latest salmon run information. (2000). Retrieved from http://www.asf.ca/
Atlantic Salmon (2011). Retrieved from http://www.miramichisalmon.ca/index.html
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Fishing atlantic salmon. (2011). Retrieved from http://www.realadventures.com/listings/1025624_Fishing-Atlantic-Salmon
Issues - invasive species. (2011). Retrieved from http://www.asf.ca/issues.php?id=12
Lake tahoe: smallmouth bass threatens native fish. (2011). Retrieved from http://www.sfgate.com/cgibin/article.cgi?f=/c/a/2011/08/16/BASK1KNS4A.DTL
"Mathews/van Holde/Ahern 3rd Edition." Pearson | Higher Education. N.p., n.d. Web. 30 Aug. 2011. <http://www.pearsonhighered.com
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Bibliography Continued
Ontario – Great Lakes Area Fact Sheets (Atlantic Salmon) (2010, July 9). Retrieved from http://www.dfo-mpo.gc.ca/regions/central/pub/factsheetsfeuilletsinfos-ogla-rglo/atlanticsalmon-saumonatlantique-eng.htm
Sandlund, O. T., Peter Johan Schei, and Åslaug Viken. Invasive species and biodiversity management . Dordrecht, Netherlands: Kluwer Academic,
1999.
Salmon at Griffin Lake Lodge (2011). Retrieved from http://www.griffinlakelodge.com/salmon.htm
Salmon Facts (2011). Retrieved from http://www.atlanticsalmontrust.org/knowledge/salmon-facts.html
Smallmouth bass. (2009). Retrieved from http://www.dfo-mpo.gc.ca/regions/central/pub/factsheets-feuilletsinfos-oglarglo/smallmouthbass-achiganpetitebouche-eng.htm
Smallmouth Bass in the Miramichi (2010). Retrieved from
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"Small Mouth Bass Threaten NB's Atlantic Salmon." nbaquaticinvasives. N.p., 28 Mar. 2011. Web. 30 Aug. 2011.
<nbaquaticinvasives.ca/en/index.php?option=com_content&view=article&id=102:smallmouth-bass-threaten-nbs-atlanticsalmon&catid=53:news&Itemid
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